WorldWideScience

Sample records for spin rate change

  1. A parametric study of the behavior of the angular momentum vector during spin rate changes of rigid body spacecraft

    Science.gov (United States)

    Longuski, J. M.

    1982-01-01

    During a spin-up or spin-down maneuver of a spinning spacecraft, it is usual to have not only a constant body-fixed torque about the desired spin axis, but also small undesired constant torques about the transverse axes. This causes the orientation of the angular momentum vector to change in inertial space. Since an analytic solution is available for the angular momentum vector as a function of time, this behavior can be studied for large variations of the dynamic parameters, such as the initial spin rate, the inertial properties and the torques. As an example, the spin-up and spin-down maneuvers of the Galileo spacecraft was studied and as a result, very simple heuristic solutions were discovered which provide very good approximations to the parametric behavior of the angular momentum vector orientation.

  2. High spin rate magnetic controller for nanosatellites

    Science.gov (United States)

    Slavinskis, A.; Kvell, U.; Kulu, E.; Sünter, I.; Kuuste, H.; Lätt, S.; Voormansik, K.; Noorma, M.

    2014-02-01

    This paper presents a study of a high rate closed-loop spin controller that uses only electromagnetic coils as actuators. The controller is able to perform spin rate control and simultaneously align the spin axis with the Earth's inertial reference frame. It is implemented, optimised and simulated for a 1-unit CubeSat ESTCube-1 to fulfil its mission requirements: spin the satellite up to 360 deg s-1 around the z-axis and align its spin axis with the Earth's polar axis with a pointing error of less than 3°. The attitude of the satellite is determined using a magnetic field vector, a Sun vector and angular velocity. It is estimated using an Unscented Kalman Filter and controlled using three electromagnetic coils. The algorithm is tested in a simulation environment that includes models of space environment and environmental disturbances, sensor and actuator emulation, attitude estimation, and a model to simulate the time delay caused by on-board calculations. In addition to the normal operation mode, analyses of reduced satellite functionality are performed: significant errors of attitude estimation due to non-operational Sun sensors; and limited actuator functionality due to two non-operational coils. A hardware-in-the-loop test is also performed to verify on-board software.

  3. Conformational change of spin labelled myoglobin

    International Nuclear Information System (INIS)

    Wajnberg, E.; Ribeiro, P.C.; Nascimento, O.R.; Bemski, G.

    1978-01-01

    A conformational change of spin labelled myoglobin have been followed by measuring the spin label's (isothiocyanate) correlation time for temperatures between 18 0 C and 44 0 C. The correlation time was calculated from Electrom Paramagnetic Ressonance Spectra using the components of the espectroscopic and hiperfine tensors obtained by fitting the powder spectra using Lefebvre and Maruani's program- [pt

  4. Spin Rate and Deflection Ratio of a Ping Pong Ball

    Directory of Open Access Journals (Sweden)

    Byung Joon Ahn

    2013-12-01

    Full Text Available To investigate the effects of a spherical object’s spin rate on the curvature of its flight, Ping Pong balls, of varying spin rates, were hit horizontally and recorded from above with a high-speed camera. It was shown that there was a proportional relationship between the ball’s spin rate and deflection ratio. Additionally, using the results of the analyzed data, a coefficient of skin friction of the Ping Pong ball was found to be approximately 0.2 under the specific conditions of this investigation.

  5. Spin Rate and Deflection Ratio of a Ping Pong Ball

    Directory of Open Access Journals (Sweden)

    Byung Joon Ahn

    2013-01-01

    Full Text Available To investigate the effects of a spherical object’s spin rate on the curvature of its flight, Ping Pong balls, of varying spin rates, were hit horizontally and recorded from above with a high-speed camera. It was shown that there was a proportional relationship between the ball’s spin rate and deflection ratio. Additionally, using the results of the analyzed data, a coefficient of skin friction of the Ping Pong ball was found to be approximately 0.2 under the specific conditions of this investigation.

  6. Conformational Changes in Bovine-Liver Glutamate Dehydrogenase : a Spin-Label Study

    NARCIS (Netherlands)

    Zantema, Alt; Vogel, Hans J.; Robillard, George T.

    1979-01-01

    A spin-labelled analogue of p-chloromercuribenzoate reacts specifically with glutamate dehydrogenase. The most marked change in the properties of the spin-labelled enzyme is a fivefold decrease in the rate of reduction of the coenzyme by L-glutamate and no change in the rate of oxidation by

  7. Spin-exchange and spin-destruction rates for the 3He-Na system

    International Nuclear Information System (INIS)

    Borel, P.I.; Soegaard, L.V.; Svendsen, W.E.; Andersen, N.

    2003-01-01

    Optically pumped Na is used as a spin-exchange partner to polarize 3 He. Polarizations around 20% have routinely been achieved in sealed spherical glass cells containing 3 He, N 2 , and a few droplets of Na. An optical technique has been developed to determine the Na- 3 He spin-exchange rate coefficient. By monitoring the Na spin relaxation ''in the dark,'' the average Na-Na spin-destruction cross section at 330 degree sign C is estimated to be around 5x10 -19 cm 2 . This value is 2-5 (15-30) times smaller than the previously reported values for the K-K (Rb-Rb) spin-relaxation cross section. In the temperature range 310-355 degree sign C the spin-exchange rate coefficient is found to be (6.1±0.6)x10 -20 cm 3 /s with no detectable temperature dependence. This value is in good agreement with a previous theoretical estimate reported by Walker and it is only slightly lower than the corresponding Rb- 3 He spin-exchange rate coefficient. The total Na- 3 He spin-destruction rate coefficient is, within errors, found to be the same as the Na- 3 He spin-exchange rate coefficient, thereby indicating that the maximum possible photon efficiency may approach unity for the Na- 3 He system. A technique, in which a charge-coupled device camera is used to take images of faint unquenched fluorescence light, has been utilized to allow for an instantaneous determination of the sodium number densities during the rate coefficient measurements

  8. Measurement of Projectile Rate of Spin

    Science.gov (United States)

    1976-02-12

    an~d Idendtir by block nsmbor) Projectile *Yaw Cards *SabotN rSpin *New 1%A@SrACT (Clod~aw - a’u M abe oft% p N mfseFsid tim flr 6r. black n~mbw) 1...a distance that permits about five revolutions of behe projectile between It and the first camera. Additional cameras may beused to increase the...or in "dark boxes ." Microflash techniques may be used to obtain adequate lighting tinder these conditions. The projectile is momentarily illuminated

  9. High-resolution magic angle spinning proton NMR analysis of human prostate tissue with slow spinning rates.

    Science.gov (United States)

    Taylor, Jennifer L; Wu, Chin-Lee; Cory, David; Gonzalez, R Gilberto; Bielecki, Anthony; Cheng, Leo L

    2003-09-01

    The development of high-resolution magic angle spinning (HR-MAS) NMR spectroscopy for intact tissue analysis and the correlations between the measured tissue metabolites and disease pathologies have inspired investigations of slow-spinning methodologies to maximize the protection of tissue pathology structures from HR-MAS centrifuging damage. Spinning sidebands produced by slow-rate spinning must be suppressed to prevent their complicating the spectral region of metabolites. Twenty-two human prostatectomy samples were analyzed on a 14.1T spectrometer, with HR-MAS spinning rates of 600 Hz, 700 Hz, and 3.0 kHz, a repetition time of 5 sec, and employing various rotor-synchronized suppression methods, including DANTE, WATERGATE, TOSS, and PASS pulse sequences. Among them, DANTE, as the simplest scheme, has shown the most potential in suppression of tissue water signals and spinning sidebands, as well as in quantifying metabolic concentrations. Copyright 2003 Wiley-Liss, Inc.

  10. Rate Change Big Bang Theory

    Science.gov (United States)

    Strickland, Ken

    2013-04-01

    The Rate Change Big Bang Theory redefines the birth of the universe with a dramatic shift in energy direction and a new vision of the first moments. With rate change graph technology (RCGT) we can look back 13.7 billion years and experience every step of the big bang through geometrical intersection technology. The analysis of the Big Bang includes a visualization of the first objects, their properties, the astounding event that created space and time as well as a solution to the mystery of anti-matter.

  11. Rate equation modelling of the optically pumped spin-exchange source

    International Nuclear Information System (INIS)

    Stenger, J.; Rith, K.

    1995-01-01

    Sources for spin polarized hydrogen or deuterium, polarized via spin-exchange of a laser optically pumped alkali metal, can be modelled by rate equations. The rate equations for this type of source, operated either with hydrogen or deuterium, are given explicitly with the intention of providing a useful tool for further source optimization and understanding. Laser optical pumping of alkali metal, spin-exchange collisions of hydrogen or deuterium atoms with each other and with alkali metal atoms are included, as well as depolarization due to flow and wall collisions. (orig.)

  12. Discovery of spin-rate-dependent asteroid thermal inertia

    OpenAIRE

    Harris, Alan; Drube, Line

    2016-01-01

    Knowledge of the surface thermal inertia of an asteroid can provide insight into surface structure: porous material has a lower thermal inertia than rock. Using WISE/NEOWISE data and our new asteroid thermal-inertia estimator we show that the thermal inertia of main-belt asteroids (MBAs) appears to increase with spin period. Similar behavior is found in the case of thermophysically-modeled thermal inertia values of near-Earth objects (NEOs). We interpret our results in terms of rapidly increa...

  13. Templated growth of PFO-DBT nanorod bundles by spin coating: effect of spin coating rate on the morphological, structural, and optical properties

    OpenAIRE

    Fakir, Muhamad Saipul; Supangat, Azzuliani; Sulaiman, Khaulah

    2014-01-01

    In this study, the spin coating of template-assisted method is used to synthesize poly[2,7-(9,9-dioctylfluorene)-alt-4,7-bis(thiophen-2-yl)benzo-2,1,3-thiadiazole] (PFO-DBT) nanorod bundles. The morphological, structural, and optical properties of PFO-DBT nanorod bundles are enhanced by varying the spin coating rate (100, 500, and 1,000 rpm) of the common spin coater. The denser morphological distributions of PFO-DBT nanorod bundles are favorably yielded at the low spin coating rate of 100 rp...

  14. A High-Spin Rate Measurement Method for Projectiles Using a Magnetoresistive Sensor Based on Time-Frequency Domain Analysis.

    Science.gov (United States)

    Shang, Jianyu; Deng, Zhihong; Fu, Mengyin; Wang, Shunting

    2016-06-16

    Traditional artillery guidance can significantly improve the attack accuracy and overall combat efficiency of projectiles, which makes it more adaptable to the information warfare of the future. Obviously, the accurate measurement of artillery spin rate, which has long been regarded as a daunting task, is the basis of precise guidance and control. Magnetoresistive (MR) sensors can be applied to spin rate measurement, especially in the high-spin and high-g projectile launch environment. In this paper, based on the theory of a MR sensor measuring spin rate, the mathematical relationship model between the frequency of MR sensor output and projectile spin rate was established through a fundamental derivation. By analyzing the characteristics of MR sensor output whose frequency varies with time, this paper proposed the Chirp z-Transform (CZT) time-frequency (TF) domain analysis method based on the rolling window of a Blackman window function (BCZT) which can accurately extract the projectile spin rate. To put it into practice, BCZT was applied to measure the spin rate of 155 mm artillery projectile. After extracting the spin rate, the impact that launch rotational angular velocity and aspect angle have on the extraction accuracy of the spin rate was analyzed. Simulation results show that the BCZT TF domain analysis method can effectively and accurately measure the projectile spin rate, especially in a high-spin and high-g projectile launch environment.

  15. Templated growth of PFO-DBT nanorod bundles by spin coating: effect of spin coating rate on the morphological, structural, and optical properties.

    Science.gov (United States)

    Fakir, Muhamad Saipul; Supangat, Azzuliani; Sulaiman, Khaulah

    2014-01-01

    In this study, the spin coating of template-assisted method is used to synthesize poly[2,7-(9,9-dioctylfluorene)-alt-4,7-bis(thiophen-2-yl)benzo-2,1,3-thiadiazole] (PFO-DBT) nanorod bundles. The morphological, structural, and optical properties of PFO-DBT nanorod bundles are enhanced by varying the spin coating rate (100, 500, and 1,000 rpm) of the common spin coater. The denser morphological distributions of PFO-DBT nanorod bundles are favorably yielded at the low spin coating rate of 100 rpm, while at high spin coating rate, it is shown otherwise. The auspicious morphologies of highly dense PFO-DBT nanorod bundles are supported by the augmented absorption and photoluminescence.

  16. Asteroid spin-rate studies using large sky-field surveys

    Science.gov (United States)

    Chang, Chan-Kao; Lin, Hsing-Wen; Ip, Wing-Huen; Prince, Thomas A.; Kulkarni, Shrinivas R.; Levitan, David; Laher, Russ; Surace, Jason

    2017-12-01

    Eight campaigns to survey asteroid rotation periods have been carried out using the intermediate Palomar Transient Factory in the past 3 years. 2780 reliable rotation periods were obtained, from which we identified two new super-fast rotators (SFRs), (335433) 2005 UW163 and (40511) 1999 RE88, and 23 candidate SFRs. Along with other three known super-fast rotators, there are five known SFRs so far. Contrary to the case of rubble-pile asteroids (i.e., bounded aggregations by gravity only), an internal cohesion, ranging from 100 to 1000 Pa, is required to prevent these five SFRs from flying apart because of their super-fast rotations. This cohesion range is comparable with that of lunar regolith. However, some candidates of several kilometers in size require unusually high cohesion (i.e., a few thousands of Pa). Therefore, the confirmation of these kilometer-sized candidates can provide important information about asteroid interior structure. From the rotation periods we collected, we also found that the spin-rate limit of C-type asteroids, which has a lower bulk density, is lower than for S-type asteroids. This result is in agreement with the general picture of rubble-pile asteroids (i.e., lower bulk density, lower spin-rate limit). Moreover, the spin-rate distributions of asteroids of 3 5 rev/day, regardless of the location in the main belt. The YORP effect is indicated to be less efficient in altering asteroid spin rates from our results when compared with the flat distribution found by Pravec et al. (Icarus 197:497-504, 2008. doi: 10.1016/j.icarus.2008.05.012). We also found a significant number drop at f = 5 rev/day in the spin-rate distributions of asteroids of D < 3 km.

  17. CHANGES IN EXCHANGE RATE REGIMES

    Directory of Open Access Journals (Sweden)

    Carmen SANDU (TODERASCU

    2014-06-01

    Full Text Available The experience of recentyears showsthat it hasa fundamentalroleformation mechanismof the exchange rateinmacroeconomic stabilization. Global economiccrises, oil shockshave shownthe difficultyoffloatingsustainabilitybyparticipants in the system. EuropeanMonetary System, focused onconcertedfloatingcurrenciestoECU, was formedunder the conditionsin which somecountries have adoptedregional monetaryarrangements(EU countries, with suchbasescurrencyregimeshybridthat combinesspecific mechanismsto those offixedratefree floating. This paperaims to demonstratethe important role thatithasthe choice ofexchange rateregimeas abasic elementin thefoundationofmacroeconomic stabilizationinstruments. Consideredan expression of thestateof the domestic economyandinternationalcompetitiveness, the exchange rate is determined bya complex set ofexternal factorsorinternalstabilityisa prerequisite forthe crisis.

  18. Rb-129Xe spin-exchange rates due to binary and three-body collisions at high Xe pressures

    International Nuclear Information System (INIS)

    Cates, G.D.; Fitzgerald, R.J.; Barton, A.S.; Bogorad, P.; Gatzke, M.; Newbury, N.R.; Saam, B.

    1992-01-01

    We have studied the spin relaxation of 129 Xe nuclei due to collisions with Rb atoms at Xe pressures of 245--1817 Torr. Our results can be characterized by two parameters, the Rb- 129 Xe velocity-averaged binary spin-exchange cross section left-angle σv right-angle and a rate γ M that characterizes spin relaxation due to van der Waals molecules. Our results complement earlier studies performed at Xe pressures of about 1 Torr and N 2 pressures of 10--100 Torr. This work is useful for predicting spin-exchange rates between polarized Rb atoms and 129 Xe nuclei

  19. Preparation and performance of novel polyvinylpyrrolidone/polyethylene glycol phase change materials composite fibers by centrifugal spinning

    Science.gov (United States)

    Zhang, Xiaoguang; Qiao, Jiaxin; Zhao, Hang; Huang, Zhaohui; Liu, Yangai; Fang, Minghao; Wu, Xiaowen; Min, Xin

    2018-01-01

    Currently, phase change materials (PCMs) composite fibers are typically prepared by electrospinning. However, electrospinning exhibits safety concerns and a low production rate, which limit its practical applications as a cost-effective fiber fabrication approach. Therefore, a novel, and simple centrifugal spinning technology is employed to extrude fibers from composite solutions using a high-speed rotary and perforated spinneret. The composite fibers based on polyvinylpyrrolidone (PVP) and polyethylene glycol (PEG) were prepared by centrifugal spinning. The SEM of PVP/PEG composite fibers indicated that the fibrous morphology is well preserved. The DSC and TGA indicated that PVP/PEG composite fibers exhibit good thermal properties.

  20. Estimating the Backup Reaction Wheel Orientation Using Reaction Wheel Spin Rates Flight Telemetry from a Spacecraft

    Science.gov (United States)

    Rizvi, Farheen

    2013-01-01

    A report describes a model that estimates the orientation of the backup reaction wheel using the reaction wheel spin rates telemetry from a spacecraft. Attitude control via the reaction wheel assembly (RWA) onboard a spacecraft uses three reaction wheels (one wheel per axis) and a backup to accommodate any wheel degradation throughout the course of the mission. The spacecraft dynamics prediction depends upon the correct knowledge of the reaction wheel orientations. Thus, it is vital to determine the actual orientation of the reaction wheels such that the correct spacecraft dynamics can be predicted. The conservation of angular momentum is used to estimate the orientation of the backup reaction wheel from the prime and backup reaction wheel spin rates data. The method is applied in estimating the orientation of the backup wheel onboard the Cassini spacecraft. The flight telemetry from the March 2011 prime and backup RWA swap activity on Cassini is used to obtain the best estimate for the backup reaction wheel orientation.

  1. 78 FR 69711 - Change in Postal Rates

    Science.gov (United States)

    2013-11-20

    ..., Priority Mail International (PMI) prices increase by an average of 1.1 percent. The existing price structure of PMI Flat Rate, Retail, Commercial Base, and Commercial Plus price categories do not change, except for the establishment of PMI Flat Rate Commercial Base and PMI Flat Rate Commercial Plus rates...

  2. On the Dependence of the X-Ray Burst Rate on Accretion and Spin Rate

    Science.gov (United States)

    Cavecchi, Yuri; Watts, Anna L.; Galloway, Duncan K.

    2017-12-01

    Nuclear burning and its dependence on the mass accretion rate are fundamental ingredients for describing the complicated observational phenomenology of neutron stars (NSs) in binary systems. Motivated by high-quality burst rate data emerging from large statistical studies, we report general calculations relating the bursting rate to the mass accretion rate and NS rotation frequency. In this first work, we ignore general relativistic effects and accretion topology, although we discuss where their inclusion should play a role. The relations we derive are suitable for different burning regimes and provide a direct link between parameters predicted by theory and what is to be expected in observations. We illustrate this for analytical relations of different unstable burning regimes that operate on the surface of an accreting NS. We also use the observed behavior of the burst rate to suggest new constraints on burning parameters. We are able to provide an explanation for the long-standing problem of the observed decrease of the burst rate with increasing mass accretion that follows naturally from these calculations: when the accretion rate crosses a certain threshold, ignition moves away from its initially preferred site, and this can cause a net reduction of the burst rate due to the effects of local conditions that set local differences in both the burst rate and stabilization criteria. We show under which conditions this can happen even if locally the burst rate keeps increasing with accretion.

  3. Spin Structure Change in Co-Substituted BiFeO3

    Science.gov (United States)

    Yamamoto, Hajime; Kihara, Takumi; Oka, Kengo; Tokunaga, Masashi; Mibu, Ko; Azuma, Masaki

    2016-06-01

    The spin structure in BiFe1-xCoxO3 (x = 0.05,0.10,0.15,0.20) was investigated as a function of Co substitution, temperature, and magnetic field. It was found that the cycloidal spin structure of BiFeO3 changed to a collinear one with spin canting and composition-independent spontaneous magnetization of ˜0.25 μB/f.u. for the Co substituted samples on heating. The collinear phase was stabilized under magnetic fields. The spin structure change was clarified also by the temperature dependence of 57Fe Mössbauer spectra, and the results indicated the first order nature of this transition.

  4. Picture change error in quasirelativistic electron/spin density, Laplacian and bond critical points

    KAUST Repository

    Bučinský, Lukáš

    2014-06-01

    The change of picture of the quasirelativistic Hartree-Fock wave functions is considered for electron/spin densities, the negative Laplacian of electron density and the appropriate bond critical point characteristics from the Quantum Theory of Atoms In Molecules (QTAIM). [OsCl5(Hpz)]- and [RuCl5(NO)]2- transition metal complexes are considered. Both, scalar relativistic and spin-orbit effects have been accounted for using the Infinite Order Two Component (IOTC) Hamiltonian. Picture change error (PCE) correction in the electron and spin densities and the Laplacian of electron density are treated analytically. Generally, PCE is found significant only in the core region of the atoms for the electron/spin density as well as Laplacian.©2014 Elsevier B.V. All rights reserved.

  5. Addition and spin exchange rate constants by longitudinal field μSR: the Mu + NO reaction

    International Nuclear Information System (INIS)

    Senba, Masayoshi; Gonzalez, A.C.; Kempton, J.R.; Arseneau, D.J.; Pan, J.J.; Tempelmann, A.; Fleming, D.G.

    1991-01-01

    The addition reaction Mu + NO + M → MuNO + M and the spin exchange reaction Mu(↑) + NO(↓)→Mu(↓)+NO(↑) have been measured by longitudinal field μSR at room temperature in the presence of up to 58 atm of N 2 as inert collider. The pressure dependence of the longitudinal relaxation rate due to the addition reaction (λ c ) demonstrates that the system is still in the low pressure regime in this pressure range. The corresponding termolecular rate constant has been determined as k 0.Mu =(1.10±0.25)x10 -32 cm 6 molecules -2 s -1 , almost 4 times smaller than the corresponding H atom reaction k 0,H =3.90x10 -32 cm 6 molecules -2 s -1 . The average value of the spin exchange rate constants in the 2.5-58 atm pressure range, k SE = (3.16±0.06)x10 -10 cm 3 molecule -1 s -1 , is in good agreement with previous values obtained by transverse field μSR. (orig.)

  6. Rate of Molecular Transfer of Allyl Alcohol across an AOT Surfactant Layer Using Muon Spin Spectroscopy.

    Science.gov (United States)

    Jayasooriya, Upali A; Clayden, Nigel J; Steytler, David C; Oganesyan, Vasily S; Peck, Jamie N T; Khasanov, Rustem; Scheuermann, Robert; Stoykov, Alexey

    2016-01-26

    The transfer rate of a probe molecule across the interfacial layer of a water-in-oil (w/o) microemulsion was investigated using a combination of transverse field muon spin rotation (TF-μSR), avoided level crossing muon spin resonance (ALC-μSR), and Monte Carlo simulations. Reverse microemulsions consist of nanometer-sized water droplets dispersed in an apolar solvent separated by a surfactant monolayer. Although the thermodynamic, static model of these systems has been well described, our understanding of their dynamics is currently incomplete. For example, what is the rate of solute transfer between the aqueous and apolar solvents, and how this is influenced by the structure of the interface? With an appropriate choice of system and probe molecule, μSR offers a unique opportunity to directly probe these interfacial transfer dynamics. Here, we have employed a well characterized w/o microemulsion stabilized by bis(2-ethylhexyl) sodium sulfosuccinate (Aerosol OT), with allyl alcohol (CH2═CH-CH2-OH, AA) as the probe. Resonances due to both muoniated radicals, CMuH2-C*H-CH2-OH and C*H2-CHMu-CH2-OH, were observed with the former being the dominant species. All resonances displayed solvent dependence, with those in the microemulsion observed as a single resonance located at intermediate magnetic fields to those present in either of the pure solvents. Observation of a single resonance is strong evidence for interfacial transfer being in the fast exchange limit. Monte Carlo calculations of the ΔM = 0 ALC resonances are consistent with the experimental data, indicating exchange rates greater than 10(9) s(-1), placing the rate of interfacial transfer at the diffusion limit.

  7. Baseline response rates affect resistance to change.

    Science.gov (United States)

    Kuroda, Toshikazu; Cook, James E; Lattal, Kennon A

    2018-01-01

    The effect of response rates on resistance to change, measured as resistance to extinction, was examined in two experiments. In Experiment 1, responding in transition from a variable-ratio schedule and its yoked-interval counterpart to extinction was compared with pigeons. Following training on a multiple variable-ratio yoked-interval schedule of reinforcement, in which response rates were higher in the former component, reinforcement was removed from both components during a single extended extinction session. Resistance to extinction in the yoked-interval component was always either greater or equal to that in the variable-ratio component. In Experiment 2, resistance to extinction was compared for two groups of rats that exhibited either high or low response rates when maintained on identical variable-interval schedules. Resistance to extinction was greater for the lower-response-rate group. These results suggest that baseline response rate can contribute to resistance to change. Such effects, however, can only be revealed when baseline response rate and reinforcement rate are disentangled (Experiments 1 and 2) from the more usual circumstance where the two covary. Furthermore, they are more cleanly revealed when the programmed contingencies controlling high and low response rates are identical, as in Experiment 2. © 2017 Society for the Experimental Analysis of Behavior.

  8. Exporter Price Response to Exchange Rate Changes

    DEFF Research Database (Denmark)

    Fosse, Henrik Barslund

    Firms exporting to foreign markets face a particular challenge: to price their exports in a foreign market when the exchange rate changes. This paper takes on pricing- to-market using a unique data set that covers rm level monthly trade at great detail. As opposed to annual trade ows, monthly trade...... theoretical contributions to the litterature on pricing-to-market and exchange rate pass-through....

  9. Dipolar Spin Ice States with a Fast Monopole Hopping Rate in CdEr2X4 (X =Se , S)

    Science.gov (United States)

    Gao, Shang; Zaharko, O.; Tsurkan, V.; Prodan, L.; Riordan, E.; Lago, J.; Fâk, B.; Wildes, A. R.; Koza, M. M.; Ritter, C.; Fouquet, P.; Keller, L.; Canévet, E.; Medarde, M.; Blomgren, J.; Johansson, C.; Giblin, S. R.; Vrtnik, S.; Luzar, J.; Loidl, A.; Rüegg, Ch.; Fennell, T.

    2018-03-01

    Excitations in a spin ice behave as magnetic monopoles, and their population and mobility control the dynamics of a spin ice at low temperature. CdEr2 Se4 is reported to have the Pauling entropy characteristic of a spin ice, but its dynamics are three orders of magnitude faster than the canonical spin ice Dy2 Ti2 O7 . In this Letter we use diffuse neutron scattering to show that both CdEr2 Se4 and CdEr2 S4 support a dipolar spin ice state—the host phase for a Coulomb gas of emergent magnetic monopoles. These Coulomb gases have similar parameters to those in Dy2 Ti2 O7 , i.e., dilute and uncorrelated, and so cannot provide three orders faster dynamics through a larger monopole population alone. We investigate the monopole dynamics using ac susceptometry and neutron spin echo spectroscopy, and verify the crystal electric field Hamiltonian of the Er3 + ions using inelastic neutron scattering. A quantitative calculation of the monopole hopping rate using our Coulomb gas and crystal electric field parameters shows that the fast dynamics in CdEr2X4 (X =Se , S) are primarily due to much faster monopole hopping. Our work suggests that CdEr2X4 offer the possibility to study alternative spin ice ground states and dynamics, with equilibration possible at much lower temperatures than the rare earth pyrochlore examples.

  10. Changes in the Earth’s Spin Rotation due to the Atmospheric Effects and Reduction in Glaciers

    Directory of Open Access Journals (Sweden)

    Sung-Ho Na

    2016-12-01

    Full Text Available The atmosphere strongly affects the Earth’s spin rotation in wide range of timescale from daily to annual. Its dominant role in the seasonal perturbations of both the pole position and spinning rate of the Earth is once again confirmed by a comparison of two recent data sets; i the Earth orientation parameter and ii the global atmospheric state. The atmospheric semi-diurnal tide has been known to be a source of the Earth’s spin acceleration, and its magnitude is re-estimated by using an enhanced formulation and an up-dated empirical atmospheric S2 tide model. During the last twenty years, an unusual eastward drift of the Earth’s pole has been observed. The change in the Earth’s inertia tensor due to glacier mass redistribution is directly assessed, and the recent eastward movement of the pole is ascribed to this change. Furthermore, the associated changes in the length of day and UT1 are estimated.

  11. Exporter Price Response to Exchange Rate Changes

    DEFF Research Database (Denmark)

    Fosse, Henrik Barslund

    Firms exporting to foreign markets face a particular challenge: to price their exports in a foreign market when the exchange rate changes. This paper takes on pricing- to-market using a unique data set that covers rm level monthly trade at great detail. As opposed to annual trade ows, monthly tra...

  12. Radar meteor rates and atmospheric density changes

    International Nuclear Information System (INIS)

    Ellyett, C.D.; Kennewell, J.A.

    1980-01-01

    It has been suggested that variations of the atmospheric scale height at meteor ablation altitudes could be responsible for the recorded correlations between radar meteor rates and solar activity. A quantitative examination of a theoretical treatment by Kaiser (personal communication) is reported which shows that his suggestion is certainly plausible and gives details of the necessary scale height changes as a function of the meteor mass exponent. (U.K.)

  13. The effect of the melting spinning cooling rate on transformation temperatures in ribbons Ti-Ni-Cu shape memory

    International Nuclear Information System (INIS)

    Ramos, A.P.; Castro, W.B.; Anselmo, G.C. dos S.

    2014-01-01

    Ti-Ni-Cu alloys have been attracting attention by their high performance of shape memory effect and decrease of thermal and stress hysteresis in comparison with Ti-Ni binary alloys. One important challenge of microsystems design is the implementation of miniaturized actuation principles efficient at the micro-scale. Shape memory alloys (SMAs) have early on been considered as a potential solution to this problem as these materials offer attractive properties like a high-power to weight ratio, large deformation and the capability to be processed at the micro-scale. Shape memory characteristics of Ti-37,8Cu-18,7Ni alloy ribbons prepared by melt spinning were investigated by means of differential scanning calorimetry and X-ray diffraction. In these experiments particular attention has been paid to change of the velocity of cooling wheel from 21 to 63 m/s. Then the cooling rates of ribbons were controlled. The effect of this cooling rate on austenitic and martensitic transformations behaviors is discussed. (author)

  14. Quantum-Classical Phase Transition of the Escape Rate of Two-Sublattice Antiferromagnetic Large Spins

    Science.gov (United States)

    Owerre, Solomon Akaraka; Paranjape, M. B.

    2014-11-01

    The Hamiltonian of a two-sublattice antiferromagnetic spins, with single (hard-axis) and double ion anisotropies described by H = J {\\hat S}1...\\hatS 2-2Jz \\hat {S}1z\\hat {S}2z+K(\\hat {S}1z2 +\\hat {S}2z2) is investigated using the method of effective potential. The problem is mapped to a single particle quantum-mechanical Hamiltonian in terms of the relative coordinate and reduced mass. We study the quantum-classical phase transition of the escape rate of this model. We show that the first-order phase transition for this model sets in at the critical value Jc = (Kc+Jz, c)/2 while for the anisotropic Heisenberg coupling H = J(S1xS2x +S1yS2y) + JzS1zS2z + K(S1z2+ S2z2) we obtain Jc = (2Kc-Jz, c)/3. The phase diagrams of the transition are also studied.

  15. High-spin states in 136La and possible structure change in the N =79 region

    Science.gov (United States)

    Nishibata, H.; Leguillon, R.; Odahara, A.; Shimoda, T.; Petrache, C. M.; Ito, Y.; Takatsu, J.; Tajiri, K.; Hamatani, N.; Yokoyama, R.; Ideguchi, E.; Watanabe, H.; Wakabayashi, Y.; Yoshinaga, K.; Suzuki, T.; Nishimura, S.; Beaumel, D.; Lehaut, G.; Guinet, D.; Desesquelles, P.; Curien, D.; Higashiyama, K.; Yoshinaga, N.

    2015-05-01

    High-spin states in the odd-odd nucleus 136La, which is located close to the β -stability line, have been investigated in the radioactive-beam-induced fusion-evaporation reaction 124Sn(17N,5 n ). The use of the radioactive beam enabled a highly sensitive and successful search for a new isomer [14+,T1 /2=187 (27 ) ns] in 136La. In the A =130 -140 mass region, no such long-lived isomer has been observed at high spin in odd-odd nuclei. The 136La level scheme was revised, incorporating the 14+ isomer and six new levels. The results were compared with pair-truncated shell model (PTSM) calculations which successfully explain the level structure of the π h11 /2⊗ν h11/2 -1 bands in 132La and 134La. The isomerism of the 14+ state was investigated also by a collective model, the cranked Nilsson-Strutinsky (CNS) model, which explains various high-spin structures in the medium-heavy mass region. It is suggested that a new type of collective structure is induced in the PTSM model by the increase of the number of π g7 /2 pairs, and/or in the CNS model by the configuration change associated with the shape change in 136La.

  16. Maternal heart rate changes during labour.

    Science.gov (United States)

    Söhnchen, N; Melzer, K; Tejada, B Martinez de; Jastrow-Meyer, N; Othenin-Girard, V; Irion, O; Boulvain, M; Kayser, B

    2011-10-01

    Labour and delivery represent a considerable effort for pregnant women. Lack of aerobic fitness may limit pushing efforts during childbirth and represents increased cardiovascular strain and risk. Increasing prevalence of sedentary behaviour and lack of aerobic fitness may reduce heart rate reserve during labour. We quantified maternal heart rate reserve (maximum heart rate minus resting heart rate) of 30 healthy pregnant women during labour and delivery and related it to habitual daily physical activity levels quantified during the third pregnancy trimester by the Pregnancy Physical Activity Questionnaire. Heart rates during labour reached values similar to those observed during moderate to heavy physical exercise. During active pushing one out of five women reached heart rates more than 90% of their heart rate reserve (188 ± 7 beats per min). Half of the women reached more than 70% of heart rate reserve (172 ± 14 beats per min). Physically inactive women used more of their heart rate reserve as physically more active women (87 ± 20% vs. 65 ± 12%, upper and lower tertile respectively, plabour is increased in physically inactive women and may potentially limit the intensity and duration of pushing efforts. Such higher cardiovascular strain in physically less active women may represent increased cardiovascular risk during labour. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  17. 77 FR 36585 - Postal Rate Changes

    Science.gov (United States)

    2012-06-19

    ... are involved. Notice at 2. Description of product and approach to rates. Air parcels are inbound... inflation increases and other factors. Id. at 1-2. Contents of Notice. The Notice incorporates by reference... dockets established for consideration of (i) the addition of this product to the competitive product list...

  18. Climate Changes Impacts Towards Sedimentation Rate At ...

    African Journals Online (AJOL)

    2018-01-15

    Jan 15, 2018 ... rivers in Malaysia are regulated for domestic, agricultural, industrial fields, residential, sewage disposal and urbanization the major pollution sources influencing the river equilibrium in Malaysia [1-3]. The changes of development, industrial and agricultural activities, human population and sedimentation ...

  19. Measuring Change with the Rating Scale Model.

    Science.gov (United States)

    Ludlow, Larry H.; And Others

    The Rehabilitation Research and Development Laboratory at the United States Veterans Administration Hines Hospital is engaged in a long-term evaluation of blind rehabilitation. One aspect of the evaluation project focuses on the measurement of attitudes toward blindness. Our aim is to measure changes in attitudes toward blindness from…

  20. Heat and spin interconversion

    International Nuclear Information System (INIS)

    Ohnuma, Yuichi; Matsuo, Mamoru; Maekawa, Sadamichi; Saitoh, Eeiji

    2017-01-01

    Spin Seebeck and spin Peltier effects, which are mutual conversion phenomena of heat and spin, are discussed on the basis of the microscopic theory. First, the spin Seebeck effect, which is the spin-current generation due to heat current, is discussed. The recent progress in research on the spin Seebeck effect are introduced. We explain the origin of the observed sign changes of the spin Seebeck effect in compensated ferromagnets. Next, the spin Peltier effect, which is the heat-current generation due to spin current, is discussed. Finally, we show that the spin Seebeck and spin Peltier effects are summarized by Onsager's reciprocal relation and derive Kelvin's relation for the spin and heat transports. (author)

  1. What Drives the European Central Bank's Interest-Rate Changes?

    DEFF Research Database (Denmark)

    Jensen, Henrik; Aastrup, Morten

    We show that the ECB's interest rate changes during 1999-2010 have been mainly driven by changes in economic activity in the Euro area. Changes in actual or expected future HICP inflation play a minor, if any, role.......We show that the ECB's interest rate changes during 1999-2010 have been mainly driven by changes in economic activity in the Euro area. Changes in actual or expected future HICP inflation play a minor, if any, role....

  2. Spin-dependent energy distribution of B-hadrons from polarized top decays considering the azimuthal correlation rate

    Directory of Open Access Journals (Sweden)

    S.M. Moosavi Nejad

    2016-04-01

    Full Text Available Basically, the energy distribution of bottom-flavored hadrons produced through polarized top quark decays t(↑→W++b(→Xb, is governed by the unpolarized rate and the polar and the azimuthal correlation functions which are related to the density matrix elements of the decay t(↑→bW+. Here we present, for the first time, the analytical expressions for the O(αs radiative corrections to the differential azimuthal decay rates of the partonic process t(↑→b+W+ in two helicity systems, which are needed to study the azimuthal distribution of the energy spectrum of the hadrons produced in polarized top decays. These spin-momentum correlations between the top quark spin and its decay product momenta will allow the detailed studies of the top decay mechanism. Our predictions of the hadron energy distributions also enable us to deepen our knowledge of the hadronization process and to test the universality and scaling violations of the bottom-flavored meson fragmentation functions.

  3. Conformational change in full-length mouse prion: A site-directed spin-labeling study

    International Nuclear Information System (INIS)

    Inanami, Osamu; Hashida, Shukichi; Iizuka, Daisuke; Horiuchi, Motohiro; Hiraoka, Wakako; Shimoyama, Yuhei; Nakamura, Hideo; Inagaki, Fuyuhiko; Kuwabara, Mikinori

    2005-01-01

    The structure of the mouse prion (moPrP) was studied using site-directed spin-labeling electron spin resonance (SDSL-ESR). Since a previous NMR study by Hornemanna et al., [Hornemanna, Korthb, Oeschb, Rieka, Widera, Wuethricha, Glockshubera, Recombinant full-length murine prion protein, mPrP (23-231): purification and spectroscopic characterization, FEBS Lett. 413 (1997) 277-281] has indicated that N96, D143, and T189 in moPrP are localized in a Cu 2+ binding region, Helix1 and Helix2, respectively, three recombinant moPrP mutations (N96C, D143C, and T189C) were expressed in an Escherichia coli system, and then refolded by dialysis under low pH and purified by reverse-phase HPLC. By using the preparation, we succeeded in preserving a target cystein residue without alteration of the α-helix structure of moPrP and were able to apply SDSL-ESR with a methane thiosulfonate spin label to the full-length prion protein. The rotational correlation times (τ) of 1.1, 3.3, and 4.8 ns were evaluated from the X-band ESR spectra at pH 7.4 and 20 deg C for N96R1, D143R1, and T189R1, respectively. τ reflects the fact that the Cu 2+ binding region is more flexible than Helix1 or Helix2. ESR spectra recorded at various temperatures revealed two phases together with a transition point at around 20 deg C in D143R1 and T189R1, but not in N96R1. With the variation of pH from 4.0 to 7.8, ESR spectra of T189R1 at 20 deg C showed a gradual increase of τ from 2.9 to 4.8 ns. On the other hand, the pH-dependent conformational changes in N96R1 and D143R1 were negligible. These results indicated that T189 located in Helix2 possessed a structure sensitive to physiological pH changes; simultaneously, N96 in the Cu 2+ binding region and D143 in Helix1 were conserved

  4. Evidence of refilled chamber gas pressure enhancing cooling rate during melt spinning of a Zr50Cu40Al10 alloy

    Directory of Open Access Journals (Sweden)

    Hong-wang Yang

    2015-07-01

    Full Text Available The influence of the refilled gas pressure on the glass forming behaviour of one of the best ternary glass forming alloys Zr50Cu40Al10 was studied for the melt spinning process. The amorphicity of as-quenched ribbons was characterized by X-ray diffraction (XRD and differential scanning calorimetry (DSC. The refilled chamber atmospheric pressure is crucial to the cooling rate of melt spinning. At high vacuum, at pressure less than 0.0001 atm, fully crystalline fragments are obtained. Monolithic amorphous ribbons were only obtained at a gas pressure of 0.1 atm or higher. The extended contact length between thecribbons and the copper wheel contributes to the high cooling rate of melt spinning. Higher chamber gas pressure leads to more turbulence of liquid metal beneath the nozzle; therefore, lower pressure is preferable at practical melt spinning processes once glass forming conditions are fulfilled.

  5. 42 CFR 413.196 - Notification of changes in rate-setting methodologies and payment rates.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 2 2010-10-01 2010-10-01 false Notification of changes in rate-setting... NURSING FACILITIES Payment for End-Stage Renal Disease (ESRD) Services and Organ Procurement Costs § 413.196 Notification of changes in rate-setting methodologies and payment rates. Link to an amendment...

  6. Determination of correlation times from selective and non-selective spin-lattice relaxation rates and their use in drug-drug and drug-albumin interaction studies

    Directory of Open Access Journals (Sweden)

    Tinoco Luzineide Wanderley

    1999-01-01

    Full Text Available The effects of the changes in sample concentration on the NMR chemical shifts and on the selective and non-selective spin-lattice relaxation rates (R1S and R1NS of the three isomers of nitrobenzaldeyde guanyl hydrazone (NBGH pure and with bovine serum albumin (BSA were measured in solution. The results wereused to determine the correlation times (tauc, showing that the degree of intermolecular drug-drug association varies with the nitro group position on the ring and that this degree of association interferes with the interaction of these drugs with BSA. The results suggest that the degree of drug-drug and drug-BSA association are related to the in vitro anti-Trypanosoma cruzi activity of these compounds.

  7. Application of an automatic yarn dismantler to track changes in cotton fibre properties during processing on a miniature spinning line

    CSIR Research Space (South Africa)

    Fassihi, A

    2014-11-01

    Full Text Available This paper reports on the application of a newly developed automatic yarn dismantler for dismantling short staple ring-spun yarns, to track changes in cotton fibre properties from lint to yarn, during processing on a miniature spinning line...

  8. Abrupt relaxation in high-spin molecules

    International Nuclear Information System (INIS)

    Chang, C.-R.; Cheng, T.C.

    2000-01-01

    Mean-field model suggests that the rate of resonant quantum tunneling in high-spin molecules is not only field-dependent but also time-dependent. The relaxation-assisted resonant tunneling in high-spin molecules produces an abrupt magnetization change during relaxation. When the applied field is very close to the resonant field, a time-dependent interaction field gradually shifts the energies of different collective spin states, and magnetization tunneling is observed as two energies of the spin states coincide

  9. Why Do Older People Change Their Ratings of Childhood Health?

    Science.gov (United States)

    Vuolo, Mike; Ferraro, Kenneth F.; Morton, Patricia M.; Yang, Ting-Ying

    2014-01-01

    A growing number of studies in life course epidemiology and biodemography make use of a retrospective question tapping self-rated childhood health to assess overall physical health status. Analyzing repeated measures of self-rated childhood health from the Health and Retirement Study (HRS), this study examines several possible explanations for why respondents might change their ratings of childhood health. Results reveal that nearly one-half of the sample revised their rating of childhood health during the 10-year observation period. Whites and relatively advantaged older adults—those with more socioeconomic resources and better memory—were less likely to revise their rating of childhood health, while those who experienced multiple childhood health problems were more likely to revise their childhood health rating, either positively or negatively. Changes in current self-rated health and several incident physical health problems were also related to the revision of one’s rating of childhood health, while the development of psychological disorders was associated with more negative revised ratings. We then illustrate the impact that these changes may have on an adult outcomes: namely, depressive symptoms. Whereas adult ratings of childhood health are likely to change over time, we recommend their use only if adjusting for factors associated with these changes, such as memory, psychological disorder, adult self-rated health, and socioeconomic resources. PMID:25359668

  10. Pseudogap Behavior of the Nuclear Spin-Lattice Relaxation Rate in FeSe Probed by 77Se-NMR

    Science.gov (United States)

    Shi, Anlu; Arai, Takeshi; Kitagawa, Shunsaku; Yamanaka, Takayoshi; Ishida, Kenji; Böhmer, Anna E.; Meingast, Christoph; Wolf, Thomas; Hirata, Michihiro; Sasaki, Takahiko

    2018-01-01

    We conducted 77Se-nuclear magnetic resonance studies of the iron-based superconductor FeSe in magnetic fields of 0.6 to 19 T to investigate the superconducting and normal-state properties. The nuclear spin-lattice relaxation rate divided by the temperature (T1T)-1 increases below the structural transition temperature Ts but starts to be suppressed below T*, well above the superconducting transition temperature Tc(H), resulting in a broad maximum of (T1T)-1 at Tp(H). This is similar to the pseudogap behavior in optimally doped cuprate superconductors. Because T* and Tp(H) decrease in the same manner as Tc(H) with increasing H, the pseudogap behavior in FeSe is ascribed to superconducting fluctuations, which presumably originate from the theoretically predicted preformed pair above Tc(H).

  11. Solar geoengineering to limit the rate of temperature change.

    Science.gov (United States)

    MacMartin, Douglas G; Caldeira, Ken; Keith, David W

    2014-12-28

    Solar geoengineering has been suggested as a tool that might reduce damage from anthropogenic climate change. Analysis often assumes that geoengineering would be used to maintain a constant global mean temperature. Under this scenario, geoengineering would be required either indefinitely (on societal time scales) or until atmospheric CO2 concentrations were sufficiently reduced. Impacts of climate change, however, are related to the rate of change as well as its magnitude. We thus describe an alternative scenario in which solar geoengineering is used only to constrain the rate of change of global mean temperature; this leads to a finite deployment period for any emissions pathway that stabilizes global mean temperature. The length of deployment and amount of geoengineering required depends on the emissions pathway and allowable rate of change, e.g. in our simulations, reducing the maximum approximately 0.3°C per decade rate of change in an RCP 4.5 pathway to 0.1°C per decade would require geoengineering for 160 years; under RCP 6.0, the required time nearly doubles. We demonstrate that feedback control can limit rates of change in a climate model. Finally, we note that a decision to terminate use of solar geoengineering does not automatically imply rapid temperature increases: feedback could be used to limit rates of change in a gradual phase-out. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  12. Structural changes induced spin-reorientation of ultrathin Mn films grown on Ag(001)

    International Nuclear Information System (INIS)

    Ouarab, N.; Haroun, A.; Baadji, N.

    2016-01-01

    The strained body centered tetragonal (bct) Mn ultrathin film from lattice parameter a=2.89 Å to lattice value of 2.73 Å induces anti-ferromagnetic behavior between Mn layers. The magnetic easy axis of Mn film was demonstrated theoretically to switch from the in-plane to out-of-plane by magneto-optical Kerr effect investigation. By including spin–orbit coupling in full potential linearized augmented plane waves and linearized muffin-tin orbitals methods, manganese ultrathin film displays different magnetic behaviors and the spin-reorientation transition is shown to be correlated to these structural changes. The calculated magnetic moment of manganese planes are enhanced and reach a value of ~4.02 μ B . The polar magneto-optical Kerr effect is calculated for a photon energy range extended to 15 eV. It shows a pronounced peak in visible light. - Highlights: • The applied strain in Mn-bct structure induces anti-ferromagnetic behavior. • The easy magnetization axis is demonstrated to be out-of-plane. • The magnetic moment of Mn-layers are enhanced and reach a value of ~4.02 μ B . • Kerr spectra show significant polar responses for Mn films in the visible range. • The prominent structures in the Kerr spectra have been identified.

  13. Degenerative changes following anterior cervical discectomy and fusion evaluated by fast spin-echo MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Wu, W. [Univ. Hospital, Linkoeping (Sweden). Dept. of Diagnostic Radiology]|[The China-Japan Friendship Hospital, Beijing (China); Thuomas, K.Aa. [Univ. Hospital, Linkoeping (Sweden). Dept. of Diagnostic Radiology; Hedlund, R. [Univ. Hospital, Linkoeping (Sweden). Dept. of Spinal Surgery; Leszniewski, W. [Univ. Hospital, Linkoeping (Sweden). Dept. of Spinal Surgery; Vavruch, L. [Univ. Hospital, Linkoeping (Sweden). Dept. of Spinal Surgery

    1996-09-01

    Purpose: To review pre- and postoperative fast spin-echo (FSE) MR images of disc herniation and spondylosis in patients after spinal cervical surgery. Material and Methods: Data were reviewed of 68 patients after anterior discectomy and fusion (ADF) operations using the Cloward technique with solid single level (C5-C6 or C6-C7) or 2-level fusions (C5-C7). The average interval from surgery to review was 37 months. Age- and sex-matched controls without neck problems were examined. Results: Preoperatively, the fusion groups had a higher incidence of protruded disc, and anterior and posterior osteophytes at the levels to be fused than the controls. Postoperatively, there was a significantly higher incidence of posterior osteophytes at the fused levels compared with the controls. Furthermore, the disc herniations and anterior osteophytes at the levels above and below the operated segments were more frequent in the fusion group. Conclusion: ADF causes acceleration of the degenerative changes at the fused level and at the levels below and above the fused segments. (orig.).

  14. Structural changes induced spin-reorientation of ultrathin Mn films grown on Ag(001)

    Energy Technology Data Exchange (ETDEWEB)

    Ouarab, N., E-mail: ouarab_nourdine@yahoo.fr [Quantum Physics and Dynamical Systems Laboratory, Ferhat Abbas University of Sétif (Algeria); Semiconductor Technology Research Center for Energetic-(CRTSE), 02, Bd Frantz Fanon Algiers, BP N° 140 (Algeria); Haroun, A. [Quantum Physics and Dynamical Systems Laboratory, Ferhat Abbas University of Sétif (Algeria); Baadji, N. [School of Physics and CRANN, Trinity College, Dublin 2 (Ireland)

    2016-12-01

    The strained body centered tetragonal (bct) Mn ultrathin film from lattice parameter a=2.89 Å to lattice value of 2.73 Å induces anti-ferromagnetic behavior between Mn layers. The magnetic easy axis of Mn film was demonstrated theoretically to switch from the in-plane to out-of-plane by magneto-optical Kerr effect investigation. By including spin–orbit coupling in full potential linearized augmented plane waves and linearized muffin-tin orbitals methods, manganese ultrathin film displays different magnetic behaviors and the spin-reorientation transition is shown to be correlated to these structural changes. The calculated magnetic moment of manganese planes are enhanced and reach a value of ~4.02 μ{sub B}. The polar magneto-optical Kerr effect is calculated for a photon energy range extended to 15 eV. It shows a pronounced peak in visible light. - Highlights: • The applied strain in Mn-bct structure induces anti-ferromagnetic behavior. • The easy magnetization axis is demonstrated to be out-of-plane. • The magnetic moment of Mn-layers are enhanced and reach a value of ~4.02 μ{sub B}. • Kerr spectra show significant polar responses for Mn films in the visible range. • The prominent structures in the Kerr spectra have been identified.

  15. Engaging a moving target: Adapting to rates of climate change

    Science.gov (United States)

    Shayegh, S.; Caldeira, K.; Moreno-Cruz, J.

    2015-12-01

    Climate change is affecting the planet and its human and natural systems at an increasing rate. As temperatures continue to rise, the international community has increasingly been considering adaptation measures to prepare for future climate change. However, most discussion around adaptation strategies has focused on preparedness for some expected amount of climate change impacts, e.g. 2 meters sea level rise. In this study, we discuss adaptation to rates of change as an alternative conceptual framework for thinking about adaptation. Adaptation is not only about adapting to amounts of change, but the rate at which these changes occur is also critically important. We ground our discussion with an example of optimal coastal investment in the face of ongoing sea level rise. Sea level rise threatens coastal assets. Finite resources could be devoted to building infrastructure further inland or to building coastal defense systems. A possible policy response could be to create a "no-build" coastal buffer zone that anticipates a future higher sea level. We present a quantitative model that illustrates the interplay among various important factors (rate of sea level rise, discount rate, capital depreciation rate, attractiveness of coastal land, etc). For some cases, strategies that combine periodic defensive investments (e.g. dikes) with planned retreat can maximize welfare when adapting to rates of climate change. In other cases, planned retreat may be optimal. It is important to prepare for ongoing increasing amounts of climate change. Preparing for a fixed amount of climate change can lead to a suboptimal solution. Climate is likely to continue changing throughout this century and beyond. To reduce adverse climate impacts, ecosystems and human systems will need to continuously adapt to a moving target.

  16. Comparison of the Success Rates and Haemodynamic Changes of ...

    African Journals Online (AJOL)

    Comparison of the Success Rates and Haemodynamic Changes of Caudal Block .and Dorsal Penile Nerve Block in Paediatric Day-Case Circumcision. Panda U. Shehu, Abubakar S. Adamu, Samboy Tanimu, Mohammed Tela, Samuelwabada Saniadamu ...

  17. Predicting changes in volcanic activity through modelling magma ascent rate.

    Science.gov (United States)

    Thomas, Mark; Neuberg, Jurgen

    2013-04-01

    It is a simple fact that changes in volcanic activity happen and in retrospect they are easy to spot, the dissimilar eruption dynamics between an effusive and explosive event are not hard to miss. However to be able to predict such changes is a much more complicated process. To cause altering styles of activity we know that some part or combination of parts within the system must vary with time, as if there is no physical change within the system, why would the change in eruptive activity occur? What is unknown is which parts or how big a change is needed. We present the results of a suite of conduit flow models that aim to answer these questions by assessing the influence of individual model parameters such as the dissolved water content or magma temperature. By altering these variables in a systematic manner we measure the effect of the changes by observing the modelled ascent rate. We use the ascent rate as we believe it is a very important indicator that can control the style of eruptive activity. In particular, we found that the sensitivity of the ascent rate to small changes in model parameters surprising. Linking these changes to observable monitoring data in a way that these data could be used as a predictive tool is the ultimate goal of this work. We will show that changes in ascent rate can be estimated by a particular type of seismicity. Low frequency seismicity, thought to be caused by the brittle failure of melt is often linked with the movement of magma within a conduit. We show that acceleration in the rate of low frequency seismicity can correspond to an increase in the rate of magma movement and be used as an indicator for potential changes in eruptive activity.

  18. Impact of interest rate changes on South African GDP and ...

    African Journals Online (AJOL)

    In this article, research findings are provided that estimate the impact of interest rate changes from a macroeconomic perspective on South African households. The study addresses the impact on the economy as a result of a 100 basis point increase in the interest rate, with the focus on households, by combining a ...

  19. Change in Family Structure and Rates of Violent Juvenile Delinquency

    OpenAIRE

    Fry, Jeannie A

    2010-01-01

    This paper addresses the question: Have the changes in family structure in the U.S. become a catalyst for juvenile delinquency? For this research, I use existing statistics for my three independent variables: divorce rates, rate of working mothers with children under age 18, percent female-headed households. My dependent variable, juvenile violent crime rates, is measured using data from the Office of Juvenile Justice and Delinquency Prevention. My control variables consist of the followin...

  20. Anomalous electric field changes and high flash rate beneath a ...

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Earth System Science; Volume 119; Issue 5. Anomalous electric field changes and high flash rate beneath a thunderstorm in northeast India ... Further,all electric field changes after a lightning discharge indicates the presence of strong Lower Positive Charge Centers (LPCC)in the active and ...

  1. Spin-dimensionality change induced by Co-doping in the chiral magnet Fe1-xCoxSi

    Science.gov (United States)

    Zhang, Lei; Menzel, Dirk; Han, Hui; Jin, Chiming; Du, Haifeng; Fan, Jiyu; Ge, Min; Ling, Langsheng; Zhang, Changjin; Pi, Li; Zhang, Yuheng

    2016-09-01

    Dimensionality is one of the most important parameters in the determination of the physical properties. Therefore, tuning of effective dimensionality is of significant importance for modulating the functionality of materials. In this work, we find that the spin-dimensionality can be changed by Co-doping in the Fe1-x Co x Si system. Investigation of the critical behavior shows that the effective critical exponents for x = 0.3 agree with the three-dimensional (3D) Heisenberg model with \\{d:n=3:3\\} (d is the spatial-dimensionality, and n is the spin-dimensionality). With the increase of Co-content, the effective critical exponents for x = 0.5 fulfill the 3D-XY model with \\{d:n=3:2\\} , while those for x = 0.6 approach the 3D-Ising model with \\{d:n=3:1\\} . These results indicate the lowering of the spin-dimensionality with the increase of Co-content in Fe1-x Co x Si. We suggest that the modulation of the spin-dimensionality in Fe1-x Co x Si should result from the enhancement of the anisotropic magnetic interaction induced by the doping of Co.

  2. Training and recovery behaviors of exchange bias in FeNi/Cu/Co/FeMn spin valves at high field sweep rates

    Energy Technology Data Exchange (ETDEWEB)

    Yang, D.Z. [Institutt for fysikk, NTNU, NO-7491 Trondheim (Norway); Key Laboratory for Magnetism and Magnetic Materials of Ministry of Education, Lanzhou University, Lanzhou 730000 (China); Kapelrud, A.; Saxegaard, M. [Institutt for fysikk, NTNU, NO-7491 Trondheim (Norway); Wahlstroem, E., E-mail: erik.wahlstrom@ntnu.no [Institutt for fysikk, NTNU, NO-7491 Trondheim (Norway)

    2012-09-15

    Training and recovery of exchange bias in FeNi/Cu/Co/FeMn spin valves have been studied by magnetoresistance curves with field sweep rates from 1000 to 4800 Oe/s. It is found that training and recovery of exchange field are proportional to the logarithm of the training cycles and recovery time, respectively. These behaviors are explained within the model based on thermal activation. For the field sweep rates of 1000, 2000 and 4000 Oe/s, the relaxation time of antiferromagnet spins are 61.4, 27.6, and 11.5 in the unit of ms, respectively, much shorter than the long relaxation time ({approx}10{sup 2}s) in conventional magnetometry measurements. - Highlights: Black-Right-Pointing-Pointer We measure antiferromagnet (AFM) spin dynamic behaviors at high field sweep rates. Black-Right-Pointing-Pointer Increasing the field sweep rates will reduce the AFM recovery and relaxation time. Black-Right-Pointing-Pointer AFM spin is in millisecond timescale, shorter the conventional report ({approx}10{sup 2}-10{sup 4}).

  3. Characterization of free radicals by electron spin resonance spectroscopy in biochars from pyrolysis at high heating rates and at high temperatures

    DEFF Research Database (Denmark)

    Trubetskaya, Anna; Jensen, Peter Arendt; Jensen, Anker Degn

    2016-01-01

    because the free radicals were trapped in a char consisting of a molten amorphous silica at heating rates of 103-104 K s-1. The experimental electron spin resonance spectroscopy spectra were analyzed by fitting to simulated data in order to identify radical types, based on g-values and line widths...

  4. Investigation of the Maximum Spin-Up Coefficients of Friction Obtained During Tests of a Landing Gear Having a Static-Load Rating of 20,000 Pounds

    Science.gov (United States)

    Batterson, Sidney A.

    1959-01-01

    An experimental investigation was made at the Langley landing loads track to obtain data on the maximum spin-up coefficients of friction developed by a landing gear having a static-load rating of 20,000 pounds. The forward speeds ranged from 0 to approximately 180 feet per second and the sinking speeds, from 2.7 feet per second to 9.4 feet per second. The results indicated the variation of the maximum spin-up coefficient of friction with forward speed and vertical load. Data obtained during this investigation are also compared with some results previously obtained for nonrolling tires to show the effect of forward speed.

  5. 15 CFR 700.16 - Changes or cancellations of priority ratings and rated orders.

    Science.gov (United States)

    2010-01-01

    ... 15 Commerce and Foreign Trade 2 2010-01-01 2010-01-01 false Changes or cancellations of priority ratings and rated orders. 700.16 Section 700.16 Commerce and Foreign Trade Regulations Relating to Commerce and Foreign Trade (Continued) BUREAU OF INDUSTRY AND SECURITY, DEPARTMENT OF COMMERCE NATIONAL...

  6. Subcutaneous insulin infusion: change in basal infusion rate has no immediate effect on insulin absorption rate

    International Nuclear Information System (INIS)

    Hildebrandt, P.; Birch, K.; Jensen, B.M.; Kuehl, C.

    1986-01-01

    Eight insulin-dependent diabetic patients were simultaneously given subcutaneous infusions (1.12 IU/h each) of 125 I-labeled Actrapid insulin in each side of the abdominal wall. After 24 h of infusion, the size of the infused insulin depots was measured by external counting for 5 h. The basal infusion rate was then doubled in one side and halved in the other for the next 4 h. Finally, 1.12 IU/h of insulin was given in both sides of the abdominal wall for an additional 3 h. The changes in the size of the depots were measured, and the absorption rates for each hour were calculated. During the first 5 h of infusion, the depot size was almost constant (approximately 5 IU) with an absorption rate that equaled the infusion rate. Doubling the infusion rate led to a significant increase in depot size, but the absorption rate remained unchanged for the first 3 h, and only thereafter was a significant increase seen. When the infusion rate was reduced to the initial 1.12 IU/h, the absorption rate remained elevated during the next 3 h. Correspondingly, when the infusion rate was decreased, the depot size also decreased, but the absorption rate remained unchanged for the first 3 h. The results show that a change in the basal insulin infusion rate does not lead to any immediate change in the insulin absorption rate. This should be considered when planning an insulin-infusion program that includes alteration(s) in the basal-rate setting

  7. Analytical description of spin-Rabi oscillation controlled electronic transitions rates between weakly coupled pairs of paramagnetic states with S=(1)/(2)

    Science.gov (United States)

    Glenn, R.; Baker, W. J.; Boehme, C.; Raikh, M. E.

    2013-04-01

    We report on the theoretical and experimental study of spin-dependent electronic transition rates which are controlled by a radiation-induced spin-Rabi oscillation of weakly spin-exchange and spin-dipolar coupled paramagnetic states (S=(1)/(2)). The oscillation components [the Fourier content, F(s)] of the net transition rates within spin-pair ensembles are derived for randomly distributed spin resonances, with an account of a possible correlation between the two distributions corresponding to individual pair partners. Our study shows that when electrically detected Rabi spectroscopy is conducted under an increasing driving field B1, the Rabi spectrum, F(s), evolves from a single peak at s=ΩR, where ΩR=γB1 is the Rabi frequency (γ is the gyromagnetic ratio), to three peaks at s=ΩR, s=2ΩR, and low s≪ΩR. The crossover between the two regimes takes place when ΩR exceeds the expectation value δ0 of the difference in the Zeeman energies within the pairs, which corresponds to the broadening of the magnetic resonance by disorder caused by a hyperfine field or distributions of Landé g factors. We capture this crossover by analytically calculating the shapes of all three peaks at an arbitrary relation between ΩR and δ0. When the peaks are well developed their widths are Δs˜δ02/ΩR. We find a good quantitative agreement between the theory and experiment.

  8. Scan Rate Dependent Spin Crossover Iron(II) Complex with Two Different Relaxations and Thermal Hysteresis fac-[Fe(II)(HL(n-Pr))3]Cl·PF6 (HL(n-Pr) = 2-Methylimidazol-4-yl-methylideneamino-n-propyl).

    Science.gov (United States)

    Fujinami, Takeshi; Nishi, Koshiro; Hamada, Daisuke; Murakami, Keishiro; Matsumoto, Naohide; Iijima, Seiichiro; Kojima, Masaaki; Sunatsuki, Yukinari

    2015-08-03

    Solvent-free spin crossover Fe(II) complex fac-[Fe(II)(HL(n-Pr))3]Cl·PF6 was prepared, where HL(n-Pr) denotes 2-methylimidazol-4-yl-methylideneamino-n-propyl. The magnetic susceptibility measurements at scan rate of 0.5 K min(-1) showed two successive spin transition processes consisting of the first spin transition T1 centered at 122 K (T1↑ = 127.1 K, T1↓ = 115.8 K) and the second spin transition T2 centered at ca. 105 K (T2↑ = 115.8 K, T2↓ = 97.2 K). The magnetic susceptibility measurements at the scan rate of 2.0, 1.0, 0.5, 0.25, and 0.1 K min(-1) showed two scan speed dependent spin transitions, while the Mössbauer spectra detected only the first spin transition T1. The crystal structures were determined at 160, 143, 120, 110, 95 K in the cooling mode, and 110, 120, and 130 K in the warming mode so as to follow the spin transition process of high-spin HS → HS(T1) → HS(T2) → low-spin LS → LS(T2) → LS(T1) → HS. The crystal structures at all temperatures have a triclinic space group P1̅ with Z = 2. The complex-cation has an octahedral N6 coordination geometry with three bidentate ligands and assume a facial-isomer with Δ- and Λ-enantimorphs. Three imidazole groups of fac-[Fe(II)(HL(n-Pr))3](2+) are hydrogen-bonded to three Cl(-) ions. The 3:3 NH(imidazole)···Cl(-) hydrogen-bonds form a stepwise ladder assembly structure, which is maintained during the spin transition process. The spin transition process is related to the structural changes of the FeN6 coordination environment, the order-disorder of PF6(-) anion, and the conformation change of n-propyl groups. The Fe-N bond distance in the HS state is longer by 0.2 Å than that in the LS state. Disorder of PF6(-) anion is not observed in the LS state but in the HS state. The conformational changes of n-propyl groups are found in the spin transition processes except for HS → HS(T1) → HS(T2).

  9. Handgun Legislation and Changes in Statewide Overall Suicide Rates.

    Science.gov (United States)

    Anestis, Michael D; Anestis, Joye C; Butterworth, Sarah E

    2017-04-01

    To examine the extent to which 4 laws regulating handgun ownership were associated with statewide suicide rate changes. To test between-group differences in statewide suicide rate changes between 2013 and 2014 in all 50 states and the District of Columbia with and without specific laws, we ran analyses of covariance. We found significant differences in suicide rate changes from 2013 to 2014 in states with mandatory waiting periods and universal background checks relative to states without such laws. States with both laws differed significantly from those with neither. No significant differences in rate changes were noted for open carry restrictions or gun lock requirements. Some state laws regulating aspects of handgun acquisition may be associated with lower statewide suicide rates. Laws regulating handgun storage and carrying practices may have a smaller effect, highlighting that legislation is likely most useful when its focus is on preventing gun ownership rather than regulating use and storage of guns already acquired. Public Health Implications. The findings add to the increasing evidence in support of a public health approach to the prevention of suicide via firearms, focusing on waiting periods and background checks.

  10. Attributing Changing Rates of Temperature Record Breaking to Anthropogenic Influences

    Science.gov (United States)

    King, Andrew D.

    2017-11-01

    Record-breaking temperatures attract attention from the media, so understanding how and why the rate of record breaking is changing may be useful in communicating the effects of climate change. A simple methodology designed for estimating the anthropogenic influence on rates of record breaking in a given time series is proposed here. The frequency of hot and cold record-breaking temperature occurrences is shown to be changing due to the anthropogenic influence on the climate. Using ensembles of model simulations with and without human-induced forcings, it is demonstrated that the effect of climate change on global record-breaking temperatures can be detected as far back as the 1930s. On local scales, a climate change signal is detected more recently at most locations. The anthropogenic influence on the increased occurrence of hot record-breaking temperatures is clearer than it is for the decreased occurrence of cold records. The approach proposed here could be applied in rapid attribution studies of record extremes to quantify the influence of climate change on the rate of record breaking in addition to the climate anomaly being studied. This application is demonstrated for the global temperature record of 2016 and the Central England temperature record in 2014.

  11. The evolutionary rate dynamically tracks changes in HIV-1 epidemics

    Energy Technology Data Exchange (ETDEWEB)

    Maljkovic-berry, Irina [Los Alamos National Laboratory; Athreya, Gayathri [Los Alamos National Laboratory; Daniels, Marcus [Los Alamos National Laboratory; Bruno, William [Los Alamos National Laboratory; Korber, Bette [Los Alamos National Laboratory; Kuiken, Carla [Los Alamos National Laboratory; Ribeiro, Ruy M [Los Alamos National Laboratory

    2009-01-01

    Large-sequence datasets provide an opportunity to investigate the dynamics of pathogen epidemics. Thus, a fast method to estimate the evolutionary rate from large and numerous phylogenetic trees becomes necessary. Based on minimizing tip height variances, we optimize the root in a given phylogenetic tree to estimate the most homogenous evolutionary rate between samples from at least two different time points. Simulations showed that the method had no bias in the estimation of evolutionary rates and that it was robust to tree rooting and topological errors. We show that the evolutionary rates of HIV-1 subtype B and C epidemics have changed over time, with the rate of evolution inversely correlated to the rate of virus spread. For subtype B, the evolutionary rate slowed down and tracked the start of the HAART era in 1996. Subtype C in Ethiopia showed an increase in the evolutionary rate when the prevalence increase markedly slowed down in 1995. Thus, we show that the evolutionary rate of HIV-1 on the population level dynamically tracks epidemic events.

  12. Nucleic Acid-Dependent Conformational Changes in CRISPR-Cas9 Revealed by Site-Directed Spin Labeling.

    Science.gov (United States)

    Vazquez Reyes, Carolina; Tangprasertchai, Narin S; Yogesha, S D; Nguyen, Richard H; Zhang, Xiaojun; Rajan, Rakhi; Qin, Peter Z

    2017-06-01

    In a type II clustered regularly interspaced short palindromic repeats (CRISPR) system, RNAs that are encoded at the CRISPR locus complex with the CRISPR-associated (Cas) protein Cas9 to form an RNA-guided nuclease that cleaves double-stranded DNAs at specific sites. In recent years, the CRISPR-Cas9 system has been successfully adapted for genome engineering in a wide range of organisms. Studies have indicated that a series of conformational changes in Cas9, coordinated by the RNA and the target DNA, direct the protein into its active conformation, yet details on these conformational changes, as well as their roles in the mechanism of function of Cas9, remain to be elucidated. Here, nucleic acid-dependent conformational changes in Streptococcus pyogenes Cas9 (SpyCas9) were investigated using the method of site-directed spin labeling (SDSL). Single nitroxide spin labels were attached, one at a time, at one of the two native cysteine residues (Cys80 and Cys574) of SpyCas9, and the spin-labeled proteins were shown to maintain their function. X-band continuous-wave electron paramagnetic resonance spectra of the nitroxide attached at Cys80 revealed conformational changes of SpyCas9 that are consistent with a large-scale domain re-arrangement upon binding to its RNA partner. The results demonstrate the use of SDSL to monitor conformational changes in CRISPR-Cas9, which will provide key information for understanding the mechanism of CRISPR function.

  13. Evaluation of biogas production rate and biochemical changes in ...

    African Journals Online (AJOL)

    The rate of biogas generation and biochemical changes in pig dung used in a simple mobile biogas digester designed and constructed at the Department of Environmental Technology, Federal University of Technology Owerri, Nigeria were evaluated. Measurable gas production started 4 days after feeding the digester with ...

  14. 18 CFR 154.313 - Schedules for minor rate changes.

    Science.gov (United States)

    2010-04-01

    ... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Schedules for minor rate changes. 154.313 Section 154.313 Conservation of Power and Water Resources FEDERAL ENERGY... component (e.g., reservation charges, demand charges, usage charges, commodity charges, injection charges...

  15. 48 CFR 41.402 - Rate changes and regulatory intervention.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Rate changes and regulatory intervention. 41.402 Section 41.402 Federal Acquisition Regulations System FEDERAL ACQUISITION... that may be of interest to other Federal agencies, and intervention before a regulatory body is...

  16. QALYs: incorporating the rate of change in quality of life.

    Science.gov (United States)

    Katostaras, Theofanis; Katostara, Niki

    2013-01-01

    The need for comparisons and economic evaluations between various health care interventions requires the evaluation of health-related quality of life. To ensure comparability in terms of the duration of any given condition, measures of quality have to integrate the parameter of time, as is the case in measures like QALY. Usually, the rate of change of quality that results from a given intervention is not incorporated in these measures, resulting in a systematically erroneous estimation of QALYs. This estimation error may lead to either a lower QALYs' value compared to the true one, when quality of life improves with a decreasing rate or deteriorates with an increasing rate, or to a higher QALYs' value compared to the true one, when quality of life improves with an increasing rate or deteriorates with a decreasing rate. The proposed method for the estimation of QALYs takes into account the rate of change in health-related quality of life at all stages and discloses deviations up to 16.67% from currently used methods.

  17. Changes in VAT rates during the economic crisis

    Directory of Open Access Journals (Sweden)

    Jan Široký

    2011-01-01

    Full Text Available To solve the current economical crisis, there are used various tools of economic policy. Some of them are changes in taxes, particularly changes in the value added tax due to its importance.Value added tax is the most harmonized tax in the single internal market of the European Communities. Although community law defines the basic legal constraints of VAT rules in individual countries, the Council Directive 2006/112/EC on the common system of value added tax, as amended, leaves some areas open for the Member States. One of the main characteristics of VAT is its tax rates which are – while maintaining specified minimal borders – in competency of Member States.Paper illustrates and evaluates the changes in tax rates of individual Member States during the economic crisis and points to their context and consequences.

  18. Mapping the Ultrafast Changes of Continuous Shape Measures in Photoexcited Spin Crossover Complexes without Long-Range Order

    Energy Technology Data Exchange (ETDEWEB)

    Canton, S. E. [Department; Zhang, X. [X-ray; Lawson Daku, M. L. [Département; Liu, Y. [Centre; Zhang, J. [School; Alvarez, S. [Departament

    2015-01-30

    Establishing a tractable yet complete reaction coordinate for the spin-state interconversion in d(4)-d(7) transition metal complexes is an integral aspect of controlling the dynamics that govern their functionality. For spin crossover phenomena, the limitations of a single-mode approximation that solely accounts for an isotropic increase in the metal-ligand bond length have long been recognized for all but the simple octahedral monodentate FeII compounds. However, identifying the coupled deformations that also impact on the unimolecular rate constants remains experimentally and theoretically challenging, especially for samples that do not display long-range order or when crystallization profoundly alters the dynamics. Owing to the rapid progress in ultrafast X-ray absorption spectroscopy (XAS), it is now possible to obtain transient structural information in any physical phase with unprecedented details. Using picosecond XAS and DFT modeling, the structure adopted by the photoinduced high-spin state of solvated [Fe(terpy)(2)](2+) (terpy: 2,2':6',2 ''-terpyridine) has been recently established. Based on these results, the methodology of the continuous shape measure is applied to classify and quantify the short-lived distortion of the first coordination shell. The reaction coordinate of the spin-state interconversion is clearly identified as a double axial bending. This finding sets a benchmark for gauging the influence of first-sphere and second-sphere interactions in the family of FeII complexes that incorporate terpy derivatives. Some implications for the optimization of related photoactive FeII complexes are also outlined.

  19. Effects of climate change on plant population growth rate and community composition change.

    Science.gov (United States)

    Chang, Xiao-Yu; Chen, Bao-Ming; Liu, Gang; Zhou, Ting; Jia, Xiao-Rong; Peng, Shao-Lin

    2015-01-01

    The impacts of climate change on forest community composition are still not well known. Although directional trends in climate change and community composition change were reported in recent years, further quantitative analyses are urgently needed. Previous studies focused on measuring population growth rates in a single time period, neglecting the development of the populations. Here we aimed to compose a method for calculating the community composition change, and to testify the impacts of climate change on community composition change within a relatively short period (several decades) based on long-term monitoring data from two plots-Dinghushan Biosphere Reserve, China (DBR) and Barro Colorado Island, Panama (BCI)-that are located in tropical and subtropical regions. We proposed a relatively more concise index, Slnλ, which refers to an overall population growth rate based on the dominant species in a community. The results indicated that the population growth rate of a majority of populations has decreased over the past few decades. This decrease was mainly caused by population development. The increasing temperature had a positive effect on population growth rates and community change rates. Our results promote understanding and explaining variations in population growth rates and community composition rates, and are helpful to predict population dynamics and population responses to climate change.

  20. QUANTITATIVE CHANGES IN REGIONAL CEREBRAL BLOOD FLOW INDUCED BY COLD, HEAT AND ISCHEMIC PAIN: A CONTINUOUS ARTERIAL SPIN LABELING STUDY

    Science.gov (United States)

    Frölich, Michael A.; Deshpande, Hrishikesh; Ness, Timothy; Deutsch, Georg

    2012-01-01

    Background The development of arterial spin labeling methods, has allowed measuring regional cerebral blood flow (rCBF) quantitatively and to show the pattern of cerebral activity associated with any state such as a sustained pain state or changes due to a neurotropic drug. Methods We studied the differential effects of three pain conditions in ten healthy subjects on a 3T scanner during resting baseline, heat, cold and ischemic pain using continuous arterial spin labeling. Results Cold pain showed the greatest absolute rCBF increases in left anterior cingulate cortex, left amygdala, left angular gyrus, and Brodmann Area 6, and a significant rCBF decrease in the cerebellum. Changes in rCBF were characteristic of the type of pain condition: cold and heat pain showed increases, while the ischemic condition showed a reduction in mean absolute gray matter flow compared to rest. An association of subjects’ pain tolerance and cerebral blood flow was noted. Conclusions The observation that quantitative rCBF changes are characteristic of the pain task employed and that there is a consistent rCBF change in Brodman area 6, an area responsible for the integration of a motor response to pain, should provide extremely useful information in the quest to develop an imaging biomarker of pain. Conceivably, response in BA6 may serve as an objective measure of analgesic efficacy. PMID:22913924

  1. Changes in Scottish suicide rates during the Second World War.

    Science.gov (United States)

    Henderson, Rob; Stark, Cameron; Humphry, Roger W; Selvaraj, Sivasubramaniam

    2006-06-23

    It is believed that total reported suicide rates tend to decrease during wartime. However, analysis of suicide rates during recent conflicts suggests a more complex picture, with increases in some age groups and changes in method choice. As few age and gender specific analyses of more distant conflicts have been conducted, it is not clear if these findings reflect a change in the epidemiology of suicide in wartime. Therefore, we examined suicide rates in Scotland before, during and after the Second World War to see if similar features were present. Data on deaths in Scotland recorded as suicide during the period 1931-1952, and population estimates for each of these years, were obtained from the General Register Office for Scotland. Using computer spreadsheets, suicide rates by gender, age and method were calculated. Forward stepwise logistic regression was used to assess the effect of gender, war and year on suicide rates using SAS V8.2. The all-age suicide rate among both men and women declined during the period studied. However, when this long-term decline is taken into account, the likelihood of suicide during the Second World War was higher than during both the pre-War and post-War periods. Suicide rates among men aged 15-24 years rose during the Second World War, peaking at 148 per million (41 deaths) during 1942 before declining to 39 per million (10 deaths) by 1945, while the rate among men aged 25-34 years reached 199 per million (43 deaths) during 1943 before falling to 66 per million (23 deaths) by 1946. This was accompanied by an increase in male suicides attributable to firearms and explosives during the War years which decreased following its conclusion. All age male and female suicide rates decreased in Scotland during World War II. However, once the general background decrease in suicide rates over the whole period is accounted for, the likelihood of suicide among the entire Scottish population during the Second World War was elevated. The overall

  2. Post-Newtonian templates for binary black-hole inspirals: the effect of the horizon fluxes and the secular change in the black-hole masses and spins

    Science.gov (United States)

    Isoyama, Soichiro; Nakano, Hiroyuki

    2018-01-01

    Black holes (BHs) in an inspiraling compact binary system absorb the gravitational-wave (GW) energy and angular-momentum fluxes across their event horizons and this leads to the secular change in their masses and spins during the inspiral phase. The goal of this paper is to present ready-to-use, 3.5 post-Newtonian (PN) template families for spinning, non-precessing, binary BH inspirals in quasicircular orbits, including the 2.5 PN and 3.5 PN horizon-flux contributions as well as the correction due to the secular change in the BH masses and spins through 3.5 PN order, respectively, in phase. We show that, for binary BHs observable by Advanced LIGO with high mass ratios (larger than  ∼10) and large aligned-spins (larger than  ∼ 0.7 ), the mismatch between the frequency-domain template with and without the horizon-flux contribution is typically above the 3% mark. For (supermassive) binary BHs observed by LISA, even a moderate mass-ratios and spins can produce a similar level of the mismatch. Meanwhile, the mismatch due to the secular time variations of the BH masses and spins is well below the 1% mark in both cases, hence this is truly negligible. We also point out that neglecting the cubic-in-spin, point-particle phase term at 3.5 PN order would deteriorate the effect of BH absorption in the template.

  3. Mind the rate. Why rate global climate change matters, and how much

    International Nuclear Information System (INIS)

    Ambrosi, Ph.

    2006-01-01

    To assess climate policies in a cost-efficiency framework with constraints on the magnitude and rate of global climate change we have built RESPONSE, an optimal control integrated assessment model. Our results show that the uncertainty about climate sensitivity leads to significant short-term mitigation efforts all the more as the arrival of information regarding this parameter is belated. There exists thus a high opportunity cost to know before 2030 the true value of this parameter, which is not totally granted so far. Given this uncertainty, a +2 deg C objective could lead to rather stringent policy recommendations for the coming decades and might prove unacceptable. Furthermore, the uncertainty about climate sensitivity magnifies the influence of the rate constraint on short-term decision, leading to rather stringent policy recommendations for the coming decades. This result is particularly robust to the choice of discount rate and to the beliefs of the decision-maker about climate sensitivity. We finally show that the uncertainty about the rate constraint is even more important for short-term decision than the uncertainty about climate sensitivity or magnitude of warming. This means that the critical rate of climate change, i.e. a transient characteristic of climate risks, matters much more than the long-term objective of climate policy, i.e. the critical magnitude of climate change. Therefore, research should be aimed at better characterising climate change risks in view to help decision-makers in agreeing on a safe guardrail to limit the rate of global warming. (author)

  4. Networking Technologies and the Rate of Technological Change

    Directory of Open Access Journals (Sweden)

    Charles Mitchell

    2005-12-01

    Full Text Available Network technology is changing rapidly and those adept at ICT analysis need resolve rate of change issues. Developments in networking now are in the direction of heuristic intelligence. Since about 1980, networking techniques have encouraged combining bits of information with imagination cognitively to improve ideas about reality. ICT enterprise projects utilize networking to sustain requisite imagination. Assumptions and misassuptions of project builders are rationally comprehended as networking sustains creative processes. The monopolization of valuable network techniques influences in the direction of esoteric networking. Data presents that substantial knowledge and networking is now occurring globally. As a netaphor, networking

  5. Temporal inhibition: effects of changes in rate of reinforcement and rate of responding1

    Science.gov (United States)

    Carr, Edward G.; Reynolds, G. S.

    1974-01-01

    Pigeons were trained to key peck on several multiple schedules in which the first of two components was always a simple fixed-interval schedule. The rate of responding at the beginning of the constant fixed-interval schedule was found to decrease with increases in the rate of reinforcement associated with the other component of the multiple schedule, but remained unchanged with decreases in the rate of responding associated with the other component. These results were interpreted as being consistent with the view that the presence and magnitude of the temporal inhibitory effects observed in a given fixed-interval schedule are a function of the properties of reinforcing stimuli, rather than of changes in the rate of responding associated with the time interval immediately preceding the fixed interval in question. PMID:16811789

  6. Changing transport and traffic risks - a CliPDaR spin off

    Science.gov (United States)

    Matulla, Christoph; Namyslo, Joachim; Gringinger, Julia; Andre, Konrad; Chimani, Barbara; Hollosi, Brigitta; Mlinar, Christian; Gschier, Roland; Fuchs, Tobias; Auer, Inge

    2014-05-01

    The delivery of goods, people's mobility, the supply with services and the free accessibility of vital resources, as hospitals for instance, are indispensable for our society. All that is possible through functioning transport networks. Globalisation, changes in technology, demography and climate as well as the strong increase in freight traffic are fundamental challenges to the reinforcement of systems in place and the planning of future transport corridors. As for climate change we present an approach to estimate the rate and amount of change than has to be managed in the future by the transport authorities. This assessment is based on combinations of weather elements that potentially harm the transport system. Such combinations (called climate indices, CIs) are evaluated for the past and the future. The evaluation of the past is done by the use of observations; the assessment of the future is based on ensembles of scenario projections, since a single projection does not allow deriving uncertainty based statements. Landslides originating from long term rain events may serve as an example. In 2013 a number of landslides caused substantial destruction and downtimes in turn. The perhaps most prominent example took place in Tirol where the Felbertauern road was hit twice by landslides and the avalanche gallery was destroyed. In our presentation at the EGU we will show changes in CIs that are related to landslides, rutting, frost thaw cycles (e.g. responsible for falling roks) and heavy precipitation events (potentially important for the flooding of transport assets as tunnels and drainage systems or dangerous to bridges). These changes refer to two future periods: the near future (2021-2050) and the remote future (2071-2100); and they refer to the climatological normal period (19961-1990). Referring to landslides there are regions showing no change and other areas with substantial increases, which predominantly occur close to topographic complex terrain. Such regions

  7. Effects of Climate Change on Plant Population Growth Rate and Community Composition Change

    OpenAIRE

    Chang, Xiao-Yu; Chen, Bao-Ming; Liu, Gang; Zhou, Ting; Jia, Xiao-Rong; Peng, Shao-Lin

    2015-01-01

    The impacts of climate change on forest community composition are still not well known. Although directional trends in climate change and community composition change were reported in recent years, further quantitative analyses are urgently needed. Previous studies focused on measuring population growth rates in a single time period, neglecting the development of the populations. Here we aimed to compose a method for calculating the community composition change, and to testify the impacts of ...

  8. How might immunization rates change if cost sharing is eliminated?

    Science.gov (United States)

    Shen, Angela K; O'Grady, Michael J; McDevitt, Roland D; Pickreign, Jeremy D; Laudenberger, Laura K; Esber, Allahna; Shortridge, Emily F

    2014-01-01

    There is a debate regarding the effect of cost sharing on immunization, particularly as the Affordable Care Act will eliminate cost sharing for recommended vaccines. This study estimates changes in immunization rates and spending associated with extending first-dollar coverage to privately insured children for four childhood vaccines. We used the 2008 National Immunization Survey and peer-reviewed literature to generate estimates of immunization status for each vaccine by age group and insurance type. We used the Truven Health Analytics 2006 MarketScan Commercial Claims and Encounters Database of line-item medical claims to estimate changes in immunization rates that would result from eliminating cost sharing, and we used the Kaiser Family Foundation/Health Research and Educational Trust Employer Health Benefits Survey to determine the prevalence of coverage for patients with first-dollar coverage, patients who face office visit cost sharing, and patients who face cost sharing for all vaccine cost components. We assumed that once cost sharing is removed, coverage rates in plans that impose cost sharing will rise to the level of plans that do not. We estimate that immunization rates would increase modestly and result in additional direct spending of $26.0 million to insurers/employers. Further, these payers would have an additional $11.0 million in spending associated with eliminating cost sharing for children already receiving immunizations. The effects of eliminating cost sharing for vaccines vary by vaccine. Overall, immunization rates will rise modestly given high insurance coverage for vaccinations, and these increases would be more substantial for those currently facing cost sharing. However, in addition to the removal of cost sharing for immunizations, these findings suggest other strategies to consider to further increase immunization rates.

  9. Lattice constant changes leading to significant changes of the spin-gapless features and physical nature in a inverse Heusler compound Zr2MnGa

    Science.gov (United States)

    Wang, Xiaotian; Cheng, Zhenxiang; Khenata, Rabah; Wu, Yang; Wang, Liying; Liu, Guodong

    2017-12-01

    The spin-gapless semiconductors with parabolic energy dispersions [1-3] have been recently proposed as a new class of materials for potential applications in spintronic devices. In this work, according to the Slater-Pauling rule, we report the fully-compensated ferrimagnetic (FCF) behavior and spin-gapless semiconducting (SGS) properties for a new inverse Heusler compound Zr2MnGa by means of the plane-wave pseudo-potential method based on density functional theory. With the help of GGA-PBE, the electronic structures and the magnetism of Zr2MnGa compound at its equilibrium and strained lattice constants are systematically studied. The calculated results show that the Zr2MnGa is a new SGS at its equilibrium lattice constant: there is an energy gap between the conduction and valence bands for both the majority and minority electrons, while there is no gap between the majority electrons in the valence band and the minority electrons in the conduction band. Remarkably, not only a diverse physical nature transition, but also different types of spin-gapless features can be observed with the change of the lattice constants. Our calculated results of Zr2MnGa compound indicate that this material has great application potential in spintronic devices.

  10. Studies on rheological, structural, optical, electrical and surface properties of LiMn2O4 thin films by varied spin rates

    Directory of Open Access Journals (Sweden)

    Balakrishnan T.

    2017-10-01

    Full Text Available LiMn2O4 thin films prepared by cost-effective spin coating method using optimized coating conditions are reported. Spin rate was varied and spin rate dependent properties were studied. Prepared films were characterized for their structural, morphological and optical properties. X-ray diffraction study of LiMn2O4 thin films confirmed the cubic spinel structure with the preferred orientation along (1 1 1 plane. Optical absorption studies showed band gap energy of 3.02 eV for the grown LiMn2O4 films. FT-IR bands assigned to asymmetric stretching modes of MnO6 group were located around 623 cm-1 and 514 cm-1 for the LiMn2O4 thin films. The weak band observed at 437 cm-1 was attributed to the LiO4 tetrahedra. The films showed high conductivity value 0.79 S/cm indicating the generation of effective network of the film for enhanced charge transport. AFM micrographs of the LiMn2O4 films deposited at 3000 rpm and 3500 rpm showed uniform distribution of fine grains throughout the surface without any dark pits, pinholes and cracks.

  11. Changes in Respiratory Rate, Blood Pressure and Heart Rate Variability in Rabbits during Orthostasis

    Directory of Open Access Journals (Sweden)

    J. Mokrý

    2006-01-01

    Full Text Available The purpose of the study was to evaluate the changes of respiratory rate, systemic blood pressure and heart rate variability parameters (HRV during orthostasis in anaesthetized rabbits. Furthermore, these changes were influenced by affecting the renin-angiotensin-aldosterone (RAA system and autonomic nervous system (ANS to study the mechanisms participating in activity of spectral frequency bands of HRV in rabbits. Ten adult rabbits (Chinchilla were anaesthetized by ketamine and flunitrazepam. The systemic blood pressure, tidal volume and respiratory rate were measured. HRV was evaluated by microcomputer system VariaPulse TF3E. The R-R intervals were derived from the electrocardiogram signal from subcutaneous needle electrodes. The evaluation of HRV in very low (VLF; 0.01-0.05 Hz, low (LF; 0.05-0.15 Hz and high frequency bands (HF; 0.15-2.0 Hz was made and parameters of frequency and time analysis were calculated. The measurements were made in horizontal (supine position, in orthostasis (the angle of 60 ° and again in supine position before and after enalapril (0.5 mg/kg b.w., metipranolol (0.2 mg/kg b.w., and after subsequent bilateral cervical vagotomy. The orthostasis in anaesthetized rabbits is accompanied by depression of respiratory rate reversed only by vagotomy. Furthermore, decrease of systemic blood pressure, unchanged heart rate and increased characteristics of heart rate variability were found, with predominant increase of spectral power in LF and VLF bands. This elevation can be eliminated only by complete blockade of ANS. Although the participation of ANS or RAA system in modification of individual HRV frequency bands is not as specific as in humans, we confirmed the participation of RAA system in determination of the VLF band.

  12. The effects of climate change and land-use change on demographic rates and population viability.

    Science.gov (United States)

    Selwood, Katherine E; McGeoch, Melodie A; Mac Nally, Ralph

    2015-08-01

    Understanding the processes that lead to species extinctions is vital for lessening pressures on biodiversity. While species diversity, presence and abundance are most commonly used to measure the effects of human pressures, demographic responses give a more proximal indication of how pressures affect population viability and contribute to extinction risk. We reviewed how demographic rates are affected by the major anthropogenic pressures, changed landscape condition caused by human land use, and climate change. We synthesized the results of 147 empirical studies to compare the relative effect size of climate and landscape condition on birth, death, immigration and emigration rates in plant and animal populations. While changed landscape condition is recognized as the major driver of species declines and losses worldwide, we found that, on average, climate variables had equally strong effects on demographic rates in plant and animal populations. This is significant given that the pressures of climate change will continue to intensify in coming decades. The effects of climate change on some populations may be underestimated because changes in climate conditions during critical windows of species life cycles may have disproportionate effects on demographic rates. The combined pressures of land-use change and climate change may result in species declines and extinctions occurring faster than otherwise predicted, particularly if their effects are multiplicative. © 2014 The Authors. Biological Reviews © 2014 Cambridge Philosophical Society.

  13. Spin coating apparatus

    Science.gov (United States)

    Torczynski, John R.

    2000-01-01

    A spin coating apparatus requires less cleanroom air flow than prior spin coating apparatus to minimize cleanroom contamination. A shaped exhaust duct from the spin coater maintains process quality while requiring reduced cleanroom air flow. The exhaust duct can decrease in cross section as it extends from the wafer, minimizing eddy formation. The exhaust duct can conform to entrainment streamlines to minimize eddy formation and reduce interprocess contamination at minimal cleanroom air flow rates.

  14. The Rate of Seasonal Changes in Temperature Alters Acclimation of Performance under Climate Change.

    Science.gov (United States)

    Nilsson-Örtman, Viktor; Johansson, Frank

    2017-12-01

    How the ability to acclimate will impact individual performance and ecological interactions under climate change remains poorly understood. Theory predicts that the benefit an organism can gain from acclimating depends on the rate at which temperatures change relative to the time it takes to induce beneficial acclimation. Here, we present a conceptual model showing how slower seasonal changes under climate change can alter species' relative performance when they differ in acclimation rate and magnitude. To test predictions from theory, we performed a microcosm experiment where we reared a mid- and a high-latitude damselfly species alone or together under the rapid seasonality currently experienced at 62°N and the slower seasonality predicted for this latitude under climate change and measured larval growth and survival. To separate acclimation effects from fixed thermal responses, we simulated growth trajectories based on species' growth rates at constant temperatures and quantified how much and how fast species needed to acclimate to match the observed growth trajectories. Consistent with our predictions, the results showed that the midlatitude species had a greater capacity for acclimation than the high-latitude species. Furthermore, since acclimation occurred at a slower rate than seasonal temperature changes, the midlatitude species had a small growth advantage over the high-latitude species under the current seasonality but a greater growth advantage under the slower seasonality predicted for this latitude under climate change. In addition, the two species did not differ in survival under the current seasonality, but the midlatitude species had higher survival under the predicted climate change scenario, possibly because rates of cannibalism were lower when smaller heterospecifics were present. These findings highlight the need to incorporate acclimation rates in ecological models.

  15. TRPA1 mediates changes in heart rate variability and cardiac ...

    Science.gov (United States)

    Short-term exposure to ambient air pollution is linked with adverse cardiovascular effects. While previous research focused primarily on particulate matter-induced responses, gaseous air pollutants also contribute to cause short-term cardiovascular effects. Mechanisms underlying such effects have not been adequately described; however, the immediate nature of the response suggests involvement of irritant neural activation and downstream autonomic dysfunction. Thus, this study examines the role of TRPA1, an irritant sensory receptor found in the airways, in the cardiac response of mice to acrolein and ozone. Conscious unrestrained wild-type C57BL/6 (WT) and TRPA1 knockout (KO) mice implanted with radiotelemeters were exposed once to 3ppm acrolein, 0.3ppm ozone, or filtered air. Heart rate (HR) and electrocardiogram (ECG) were recorded continuously before, during and after exposure. Analysis of ECG morphology, incidence of arrhythmia and heart rate variability (HRV) were performed. Cardiac mechanical function was assessed using a Langendorff perfusion preparation 24h post-exposure. Acrolein exposure increased HRV independent of HR, as well as incidence of arrhythmia. Acrolein also increased left ventricular developed pressure in WT mice at 24h post-exposure. Ozone did not produce any changes in cardiac function. Neither gas produced ECG effects, changes in HRV, arrhythmogenesis, or mechanical function in KO mice. These data demonstrate that a single exposure to ac

  16. Effect of physiological heart rate variability on quantitative T2 measurement with ECG-gated Fast Spin Echo (FSE) sequence and its retrospective correction.

    Science.gov (United States)

    de Roquefeuil, Marion; Vuissoz, Pierre-André; Escanyé, Jean-Marie; Felblinger, Jacques

    2013-11-01

    Quantitative T2 measurement is applied in cardiac Magnetic Resonance Imaging (MRI) for the diagnosis and follow-up of myocardial pathologies. Standard Electrocardiogram (ECG)-gated fast spin echo pulse sequences can be used clinically for T2 assessment, with multiple breath-holds. However, heart rate is subject to physiological variability, which causes repetition time variations and affects the recovery of longitudinal magnetization between TR periods. The bias caused by heart rate variability on quantitative T2 measurements is evaluated for fast spin echo pulse sequence. Its retrospective correction based on an effective TR is proposed. Heart rate variations during breath-holds are provided by the ECG recordings from healthy volunteers. T2 measurements were performed on a phantom with known T2 values, by synchronizing the sequence with the recorded ECG. Cardiac T2 measurements were performed twice on six volunteers. The impact of T1 on T2 is also studied. Maximum error in T2 is 26% for phantoms and 18% for myocardial measurement. It is reduced by the proposed compensation method to 20% for phantoms and 10% for in vivo measurements. Only approximate knowledge of T1 is needed for T2 correction. Heart rate variability may cause a bias in T2 measurement with ECG-gated FSE. It needs to be taken into account to avoid a misleading diagnosis from the measurements. © 2013.

  17. Spin current

    CERN Document Server

    Valenzuela, Sergio O; Saitoh, Eiji; Kimura, Takashi

    2012-01-01

    In a new branch of physics and technology called spin-electronics or spintronics, the flow of electrical charge (usual current) as well as the flow of electron spin, the so-called 'spin current', are manipulated and controlled together. This book provides an introduction and guide to the new physics and application of spin current.

  18. Spin Hall effect and spin swapping in diffusive superconductors

    Science.gov (United States)

    Espedal, Camilla; Lange, Peter; Sadjina, Severin; Mal'shukov, A. G.; Brataas, Arne

    2017-02-01

    We consider the spin-orbit-induced spin Hall effect and spin swapping in diffusive superconductors. By employing the nonequilibrium Keldysh Green's function technique in the quasiclassical approximation, we derive coupled transport equations for the spectral spin and particle distributions and for the energy density in the elastic scattering regime. We compute four contributions to the spin Hall conductivity, namely, skew scattering, side jump, anomalous velocity, and the Yafet contribution. The reduced density of states in the superconductor causes a renormalization of the spin Hall angle. We demonstrate that all four of these contributions to the spin Hall conductivity are renormalized in the same way in the superconducting state. In its simplest manifestation, spin swapping transforms a primary spin current into a secondary spin current with swapped current and polarization directions. We find that the spin-swapping coefficient is not explicitly but only implicitly affected by the superconducting gap through the renormalized diffusion coefficients. We discuss experimental consequences for measurements of the (inverse) spin Hall effect and spin swapping in four-terminal geometries. In our geometry, below the superconducting transition temperature, the spin-swapping signal is increased an order of magnitude while changes in the (inverse) spin Hall signal are moderate.

  19. Video rate electrical impedance tomography of vascular changes: preclinical development

    International Nuclear Information System (INIS)

    Halter, Ryan; Hartov, Alex; Paulsen, Keith

    2008-01-01

    Peripheral vasculature disease is strongly correlated with cardiovascular-associated mortality. Monitoring circulation health, especially in the peripheral limbs, is vital to detecting clinically significant disease at a stage when it can still be addressed through medical intervention. Electrical impedance tomography (EIT) maps the electrical properties of tissues within the body and has been used to image dynamically varying physiology, including blood flow. Here, we suggest that peripheral vasculature health can be monitored with EIT by imaging the hemodynamics of peripheral vessels and the surrounding tissues during reactive hyperemia testing. An analysis based on distinguishability theory is presented that indicates that an EIT system capable of making measurements with a precision of 50 µV may be able to detect small changes in vessel size associated with variations in blood flow. An EIT system with these precision capabilities is presented that is able to collect data at frame rates exceeding 30 fps over a broad frequency range up to 10 MHz. The system's high speed imaging performance is verified through high contrast phantom experiments and through physiological imaging of induced ischemia with a human forearm. Region of interest analysis of the induced ischemia images shows a marked decrease in conductivity over time, changing at a rate of approximately −3 × 10 −7 S m −1 s −1 , which is the same order of magnitude as reported in the literature. The distinguishability analysis suggests that a system such as the one developed here may provide a means to characterize the hemodynamics associated with blood flow through the peripheral vasculature

  20. A controllable spin prism

    International Nuclear Information System (INIS)

    Hakioglu, T

    2009-01-01

    Based on Khodas et al (2004 Phys. Rev. Lett. 92 086602), we propose a device acting like a controllable prism for an incident spin. The device is a large quantum well where Rashba and Dresselhaus spin-orbit interactions are present and controlled by the plunger gate potential, the electric field and the barrier height. A totally destructive interference can be manipulated externally between the Rashba and Dresselhaus couplings. The spin-dependent transmission/reflection amplitudes are calculated as the control parameters are changed. The device operates as a spin prism/converter/filter in different regimes and may stimulate research in promising directions in spintronics in analogy with linear optics.

  1. Changes in heart rate and heart rate variability as a function of age in Thoroughbred horses.

    Science.gov (United States)

    Ohmura, Hajime; Jones, James H

    2017-01-01

    We investigated changes in heart rate (HR) and HR variability as a function of age in newborn foals to old Thoroughbred horses. Experiments were performed on a total of 83 healthy and clinically normal Thoroughbred horses. Resting HR decreased with age from birth. The relationship between age and HR fit the equation Y=48.2X -0.129 (R 2 =0.705); the relationship between age and HR for horses 0-7 years old fit the equation Y=44.1X -0.179 (R 2 =0.882). Seven-day-old horses had the highest HR values (106 ± 10.3 beat/min). The low frequency (LF) and high frequency (HF) powers increased with age in newborn to old horses. These changes in HR and HR variability appear to result from the effects of ageing. Three- to seven-year-old race horses had the lowest HR values (32.9 ± 3.5 beat/min) and the highest LF and HF powers except for the HF powers in the oldest horses. Race training may have contributed to these changes. Horses of ages greater than 25 years old had the highest HF powers and the lowest LF/HF ratios. In individual horses, 8 of the 15 horses over 25 years old had LF/HF ratios of less than 1.0; their HR variability appears to be unique, and they may have a different autonomic balance than horses of younger age.

  2. Seismic Rate Changes Associated with Seasonal, Annual, and Decadal Changes in the Cryosphere

    Science.gov (United States)

    Sauber-Rosenberg, Jeanne

    2012-01-01

    Near the Bering Glacier Global Fiducial site in southern Alaska large cryospheric fluctuations occur in a region of upper crustal faulting and folding associated with collision and accretion of the Yakutat terrane. In this study we report constraints on seasonal, annual and decadal cryospheric changes estimated over the last decade from field, aircraft and satellite measurements, and we evaluate the influence of cryospheric changes on the background seismic rate. Multi-year images from the Bering Glacier global fiducial site are available since mid-2003 to constrain changes in extent of the Bering Glacier and to discern feature changes in the glacial surface. Starting around the same time, satellite gravimetric measurements from the Gravity Recovery and Climate experiment (GRACE) commenced. Large spatial-scale mass change calculated from the GRACE 1deg x 1deg mascon solution of Luthcke et al. [2012] indicate a general trend of annual ice mass loss for southern Alaska but with large, variable seasonal mass fluctuations. Since 2007, the station position of a continuous GPS site near Cape Yakataga (Alaska EarthScope PBO site, AB35) has been available as well. In addition to changes in the geodetic position due to tectonic motion, this GPS station shows large seasonal excursions in the detrended vertical and horizontal position components consistent with snow loading in the fall and winter and melt onset/mass decrease in the spring/summer. To better understand the timing of processes responsible for the onset of cryospheric mass loss documented in the GRACE data, we examined changes in the snow cover extent and the onset of melt in the spring. We calculated the surface displacements of the solid Earth and theoretical earthquake failure criteria associated with these annual and seasonal ice and snow changes using layered elastic half-space. Additionally, we compared the seismic rate (M>1.8) from a reference background time period against other time periods with variable

  3. Observation of the spin Nernst effect

    Science.gov (United States)

    Meyer, S.; Chen, Y.-T.; Wimmer, S.; Althammer, M.; Wimmer, T.; Schlitz, R.; Geprägs, S.; Huebl, H.; Ködderitzsch, D.; Ebert, H.; Bauer, G. E. W.; Gross, R.; Goennenwein, S. T. B.

    2017-10-01

    The observation of the spin Hall effect triggered intense research on pure spin current transport. With the spin Hall effect, the spin Seebeck effect and the spin Peltier effect already observed, our picture of pure spin current transport is almost complete. The only missing piece is the spin Nernst (-Ettingshausen) effect, which so far has been discussed only on theoretical grounds. Here, we report the observation of the spin Nernst effect. By applying a longitudinal temperature gradient, we generate a pure transverse spin current in a Pt thin film. For readout, we exploit the magnetization-orientation-dependent spin transfer to an adjacent yttrium iron garnet layer, converting the spin Nernst current in Pt into a controlled change of the longitudinal and transverse thermopower voltage. Our experiments show that the spin Nernst and the spin Hall effect in Pt are of comparable magnitude, but differ in sign, as corroborated by first-principles calculations.

  4. Change in teachers' ratings of attention problems and subsequent change in academic achievement: a prospective analysis.

    Science.gov (United States)

    Breslau, N; Breslau, J; Peterson, E; Miller, E; Lucia, V C; Bohnert, K; Nigg, J

    2010-01-01

    Recent research has documented a link between attention problems at school entry and later academic achievement. Little is known about the association of change in attention problems during the early school years with subsequent change in academic achievement. A community-based cohort was followed up and assessed for attention problems at ages 6 and 11 (Teacher Report Form; TRF) and for academic achievement in math and reading at ages 11 and 17 (Woodcock-Johnson Psycho-Educational Battery). Complete data were available on 590 children (72% of the initial sample). Ordinary least squares regressions were used to estimate change in academic achievement from age 11 to age 17 in relation to change in TRF-attention problems from age 6 to age 11. Children's IQ and family factors were statistically controlled. Change in teachers' ratings of attention problems from age 6 to age 11 was negatively associated with change in math and reading from age 11 to age 17, controlling for children's IQ and family factors. Externalizing problems had no significant association with change in math or reading, when added to the multivariable model. Increases in teacher-rated attention problems from age 6 to age 11 were followed by declines in academic achievement from age 11 to age 17; decreases were followed by gains. The results underscore the need for research on the course of attention problems, the testing of interventions to address children's early attention problems and the evaluation of their effects on subsequent academic achievement.

  5. Spin relaxation in quantum dots: Role of the phonon modulated spin-orbit interaction

    Science.gov (United States)

    Alcalde, A. M.; Romano, C. L.; Sanz, L.; Marques, G. E.

    2010-01-01

    We calculate the spin relaxation rates in a parabolic InSb quantum dots due to the spin interaction with acoustical phonons. We considered the deformation potential mechanism as the dominant electron-phonon coupling in the Pavlov-Firsov spin-phonon Hamiltonian. We analyze the behavior of the spin relaxation rates as a function of an external magnetic field and mean quantum dot radius. Effects of the spin admixture due to Dresselhaus contribution to spin-orbit interaction are also discussed.

  6. PREFACE: Spin Electronics

    Science.gov (United States)

    Dieny, B.; Sousa, R.; Prejbeanu, L.

    2007-04-01

    Conventional electronics has in the past ignored the spin on the electron, however things began to change in 1988 with the discovery of giant magnetoresistance in metallic thin film stacks which led to the development of a new research area, so called spin-electronics. In the last 10 years, spin-electronics has achieved a number of breakthroughs from the point of view of both basic science and application. Materials research has led to several major discoveries: very large tunnel magnetoresistance effects in tunnel junctions with crystalline barriers due to a new spin-filtering mechanism associated with the spin-dependent symmetry of the electron wave functions new magnetic tunnelling barriers leading to spin-dependent tunnelling barrier heights and acting as spin-filters magnetic semiconductors with increasingly high ordering temperature. New phenomena have been predicted and observed: the possibility of acting on the magnetization of a magnetic nanostructure with a spin-polarized current. This effect, due to a transfer of angular momentum between the spin polarized conduction electrons and the local magnetization, can be viewed as the reciprocal of giant or tunnel magnetoresistance. It can be used to switch the magnetization of a magnetic nanostructure or to generate steady magnetic excitations in the system. the possibility of generating and manipulating spin current without charge current by creating non-equilibrium local accumulation of spin up or spin down electrons. The range of applications of spin electronics materials and phenomena is expanding: the first devices based on giant magnetoresistance were the magnetoresistive read-heads for computer disk drives. These heads, introduced in 1998 with current-in plane spin-valves, have evolved towards low resistance tunnel magnetoresistice heads in 2005. Besides magnetic recording technology, these very sensitive magnetoresistive sensors are finding applications in other areas, in particular in biology. magnetic

  7. Influence of cooling rate in planar thermally assisted magnetic random access memory: Improved writeability due to spin-transfer-torque influence

    International Nuclear Information System (INIS)

    Chavent, A.; Ducruet, C.; Portemont, C.; Creuzet, C.; Alvarez-Hérault, J.; Vila, L.; Sousa, R. C.; Prejbeanu, I. L.; Dieny, B.

    2015-01-01

    This paper investigates the effect of a controlled cooling rate on magnetic field reversal assisted by spin transfer torque (STT) in thermally assisted magnetic random access memory. By using a gradual linear decrease of the voltage at the end of the write pulse, the STT decays more slowly or at least at the same rate as the temperature. This condition is necessary to make sure that the storage layer magnetization remains in the desired written direction during cooling of the cell. The influence of the write current pulse decay rate was investigated on two exchange biased synthetic ferrimagnet (SyF) electrodes. For a NiFe based electrode, a significant improvement in writing reproducibility was observed using a gradual linear voltage transition. The write error rate decreases by a factor of 10 when increasing the write pulse fall-time from ∼3 ns to 70 ns. For comparison, a second CoFe/NiFe based electrode was also reversed by magnetic field assisted by STT. In this case, no difference between sharp and linear write pulse fall shape was observed. We attribute this observation to the higher thermal stability of the CoFe/NiFe electrode during cooling. In real-time measurements of the magnetization reversal, it was found that Ruderman-Kittel-Kasuya-Yosida (RKKY) coupling in the SyF electrode vanishes for the highest pulse voltages that were used due to the high temperature reached during write. As a result, during the cooling phase, the final state is reached through a spin-flop transition of the SyF storage layer

  8. Exchange rates and climate change: An application of fund

    NARCIS (Netherlands)

    Tol, R.S.J.

    2006-01-01

    As economic and emissions scenarios assume convergence of per capita incomes, they are sensitivity to the exchange rate used for international comparison. Particularly, developing countries are project to grow slower with a purchasing power exchange rate than with a market exchange rate. Different

  9. 7 CFR Exhibit B to Subpart A of... - Notice of Change in Interest Rate

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 14 2010-01-01 2009-01-01 true Notice of Change in Interest Rate B Exhibit B to... Interest Rate (insert date) Notice of Change in Interest Rate (insert borrower's address) Re: □ □ Fund code... ___, for the original amount of ___ dollars ($___) provides for a change in interest rate for a limited...

  10. Synchrotron radiation structure analyses of the light-induced radical pair of a hexaarylbiimidazolyl derivative. Origin of the spin-multiplicity change

    CERN Document Server

    Kawano, M; Matsubara, K; Imabayashi, H; Mitsumi, M; Toriumi, K; Ohashi, Y

    2002-01-01

    In situ synchrotron radiation structure analyses of a light-induced radical pair from o-Cl-HABI were performed by using an X-ray vacuum camera at 23-70K at the BL02B1 station of SPring-8. The combined results of X-ray analysis with theoretical calculation, IR, and UV-vis spectroscopy reveal that a slight conformational change of the radical pair causes the drastic spin-multiplicity change during 2-140K. (author)

  11. 78 FR 283 - 2013 Rate Changes for the Basetime, Overtime, Holiday, and Laboratory Services Rates

    Science.gov (United States)

    2013-01-03

    ... cost of living increase, plus the benefits rate, plus the travel and operating rate, plus the overhead... Hours ($463,760,597/16,663,724)] = $27.83 + ($27.83 * 1.9% (calendar year 2013 Cost of Living Increase... calendar year's percentage of cost of living increase, multiplied by 1.5, plus the benefits rate, plus the...

  12. Population Changes, the Baby Boom, and the Unemployment Rate.

    Science.gov (United States)

    Flaim, Paul O.

    1990-01-01

    The influx of baby boomers into the job market exerted considerable upward pressure on the unemployment rate during the 1960s and 1970s; the maturing of this large population group helped lower the rate in the 1980s and should do so again in the 1990s. (Author)

  13. Changes in Peak Expiratory Flow Rate, Blood Pressure and Pulse ...

    African Journals Online (AJOL)

    We studied the effect of different concentrations of coffee on peak expiratory flow rate (PEFR), blood pressure and pulse rate in an attempt to determine some physiological effects of coffee intake. 18 apparently healthy adult males, age range 20 to 30 years, were recruited for the study over a three day period. Varying ...

  14. In Situ AFM Imaging of Microstructural Changes Associated with The Spin Transition in [Fe(Htrz)₂(Trz)](Bf₄) Nanoparticles.

    Science.gov (United States)

    Manrique-Juárez, María D; Suleimanov, Iurii; Hernández, Edna M; Salmon, Lionel; Molnár, Gábor; Bousseksou, Azzedine

    2016-06-30

    Topographic images of [Fe(Htrz)₂(trz)](BF₄) nanoparticles were acquired across the first-order spin transition using variable-temperature atomic force microscopy (AFM) in amplitude modulation mode. These studies revealed a complex morphology of the particles consisting of aggregates of small nanocrystals, which expand, separate and re-aggregate due to the mechanical stress during the spin-state switching events. Both reversible (prompt or slow recovery) and irreversible effects (fatigue) on the particle morphology were evidenced and correlated with the spin crossover properties.

  15. Credit Rating Change and Capital Structure in Latin America

    Directory of Open Access Journals (Sweden)

    Dany Rogers

    2016-04-01

    Full Text Available This study analyzes the impact of imminent reclassification of credit rating on the decision-making regarding capital structure of non-financial corporations listed in Latin America. Despite the importance attributed by the market agents and the existence of empirical evidence of the effect caused by rating in the capital structure of companies in developed countries, this issue is still incipient in Latin-American countries. For this purpose, all the non-financial corporation owners of, at least one corporate rating issued by an international rating agency were taken into account, with the requirement of being listed on a stock exchange in at least one Latin-American country. Through a data panel analysis comprising the period between 2001 and 2010 and by making use of the Generalized Method of Moments (GMM, the main results that were achieved did not indicate that non-financial corporations listed in Latin America, with imminent reclassification of ratings, adopt less debts than those without an imminent reclassification of their ratings. These findings suggest that the imminent reclassifications of credit ratings do not present important information for managers of non-financial corporations in Latin America when making decisions about capital structure.

  16. Climate changes impacts towards sedimentation rate at Terengganu ...

    African Journals Online (AJOL)

    The climate changes caused by rainfall and stream flow are not the major contribution the changing of water level. This study was carried out at Terengganu River Basin in wet and dry season to assess the sedimentation problem and its relationship with hydrological characteristic. Three parameters analyzed based on ...

  17. Aging and physiological changes of the kidneys including changes in glomerular filtration rate.

    Science.gov (United States)

    Musso, Carlos G; Oreopoulos, Dimitrios G

    2011-01-01

    In addition to the structural changes in the kidney associated with aging, physiological changes in renal function are also found in older adults, such as decreased glomerular filtration rate, vascular dysautonomia, altered tubular handling of creatinine, reduction in sodium reabsorption and potassium secretion, and diminished renal reserve. These alterations make aged individuals susceptible to the development of clinical conditions in response to usual stimuli that would otherwise be compensated for in younger individuals, including acute kidney injury, volume depletion and overload, disorders of serum sodium and potassium concentration, and toxic reactions to water-soluble drugs excreted by the kidneys. Additionally, the preservation with aging of a normal urinalysis, normal serum urea and creatinine values, erythropoietin synthesis, and normal phosphorus, calcium and magnesium tubular handling distinguishes decreased GFR due to normal aging from that due to chronic kidney disease. Copyright © 2011 S. Karger AG, Basel.

  18. How Does the PAC Respond to Changes in the Payment Rate

    Data.gov (United States)

    U.S. Department of Health & Human Services — How Does the Volume of Post-Acute Care Respond to Changes in the Payment Rate Measure the effect of changes from 1997 to 2001 in Medicares payment rates for skilled...

  19. Account of states with indefinite spin in calculations of intercombination collisional transitions

    International Nuclear Information System (INIS)

    Gordeev, S.V.; Chirtsov, A.S.

    1986-01-01

    States with indefinite spin are used in the second order of the perturbation theory as intermediate states for calculating electronic collisional transitions with changing spin between excited states of atoms. The rate coefficient for 4 1 P-4 3 D transition in helium is estimated

  20. Changing HPV vaccination rates in bisexual and lesbian women.

    Science.gov (United States)

    Polek, Carolee; Hardie, Thomas

    2017-06-01

    Human papillomavirus (HPV) vaccination rates continue to be below national targets for women and lower in some sexual minorities. HPV is a primary causal agent in cervical cancer, from which members of the lesbian and bisexual community mistakenly believe they are at low risk. This study characterized rates of HPV vaccination in women based on their sexual orientation. Data were obtained from the Centers for Disease Control and Prevention's National Health Interview Survey 2013-2014. This survey evaluated 5695 women-113 (2%) lesbian, 135 (2.4%) bisexual, and 5446 (95.6%) heterosexual women ages 18-26 in 2006-using logistic regression. A dependent variable of having had HPV vaccination and independent variable of sexual orientation was used. Significant differences were found in vaccine uptake based on sexual orientation. Bisexual women were most likely to be vaccinated, and differed significantly from heterosexual and lesbians which did not differ significantly from each other. The results suggest improvement in sexual minority rates but this finding is tempered by the low rates of vaccination in adult women. The low vaccination rates in adult women and sexual minorities merit further study. The low rates may be a function of the transition from pediatric to adult care and/or practice barriers perceived by sexual minorities. ©2017 American Association of Nurse Practitioners.

  1. Reproductive value, the stable stage distribution, and the sensitivity of the population growth rate to changes in vital rates

    Directory of Open Access Journals (Sweden)

    Hal Caswell

    2010-09-01

    Full Text Available The population growth rate, or intrinsic rate of increase, measures the potential rate of growth of a population with specified and fixed vital rates.The sensitivity of population growth rate to changes in the vital rates can be written in terms of the stable stage or age distribution and the reproductive value distribution. If the vital rate measures the rate of production of one type of individual by another, then the sensitivity of growth rate is proportional to the reproductive value of the destination type and the representation in the stable stage distribution of the source type. This formal relationship exists in three forms: one limited to age-classified populations, a second that applies to stage- or age-classified populations, and a third that uses matrix calculus. Each uses a different set of formal demographic techniques; together they provide a relationship that beautifully cuts across different types of demographic models.

  2. 76 FR 80326 - 2012 Rate Changes for the Basetime, Overtime, Holiday, and Laboratory Services Rates

    Science.gov (United States)

    2011-12-23

    ... quotient multiplied by the calendar year's percentage of cost of living increase, plus the benefits rate... * 1.9% (calendar year 2011 Cost of Living Increase)) = $28.17 + $8.63(benefits rate) + $.75 (travel... year's regular hours, plus that quotient multiplied by the calendar year's percentage of cost of living...

  3. 18 CFR 346.2 - Material in support of initial rates or change in rates.

    Science.gov (United States)

    2010-04-01

    ..., debt ratio, weighted cost of capital, and costs of debt and equity. (4) Statement D—income taxes. This... capital, combining the rate of return on debt capital and the real rate of return on equity capital. Items... statement must show: return allowance, interest expense, equity return, annual amortization of deferred...

  4. Measurement of the spin and temperature dependence of the ddμ-molecule formation rate in solid and liquid deuterium

    International Nuclear Information System (INIS)

    Demin, D.L.; Drebushko, A.E.; Dzhelepov, V.P.

    1996-01-01

    Ddμ molecule formation rates have been measured from the two hyperfine states of the dμ-atom in the temperature range of T=5-30 K. Results are consistent with the measurement of the TRIUMF group at T=3 K and contradict theoretical predictions. The work was performed on the JINR phasotron (Dubna). 23 refs., 10 figs.; 2 tabs

  5. [Change of awareness level of the Japanese Food Guide Spinning Top and relation with sociodemographic and health-related characteristics].

    Science.gov (United States)

    Takaizumi, Kanae; Harada, Kazuhiro; Nakamura, Yoshio

    2011-11-01

    The purpose of this study was to examine the sociodemographic and health-related characteristics of those who are unaware of the Japanese Food Guide Spinning Top (Food Guide). A longitudinal study was conducted using an Internet-based questionnaire with 1,012 Japanese adults (40.2 +/- 10.0 years, mean +/- SD) recruited from registrants of a Japanese social research company. Conducted between November 2007 (T1) and December 2008 (T2), the survey included items on awareness level ("I know the contents." "I have heard of this Guide." or "I have not heard of this Guide.") of the Food Guide as the dependent variable, and demographics factors (e.g., age, education status, marital status, household income, and employment status) and health-related characteristics (obesity, abdominal obesity, and insufficient physical activity) as the independent variables. Multivariate logistic regression analysis was used to analyze the relation between awareness level and each variable. The relation between change of awareness level (T1-T2) and each variable was analyzed using a chi-square test. All the analyses were stratified by gender. In the multivariate logistic regression analysis adjusted for all variables, men with a household income of 5,000,000-10,000,000 yen (OR=1.78; 95% CI=1.10-2.88) were positively associated with awareness level ("I have heard of this Guide."). In contrast, unmarried women were negatively associated with awareness level in T1 ("I know the contents"; OR=0.35; 95% CI=0.17-0.70. "I have heard of this Guide"; OR=0.50; 95% CI=0.27-0.92). In men, the awareness level of the Food Guide increased from T1 to T2, change of awareness level (T1; "I have not heard of this Guide") and education status being related (P=0.023). In women, the awareness levels overall did not improve from T1 to T2, but change of awareness level (T1; "I have heard of this Guide") was associated with household income (P<0.001). In both men and women, change of awareness level was not

  6. Estimated migration rates under scenarios of global climate change.

    Science.gov (United States)

    Jay R. Malcolm; Adam Markham; Ronald P. Neilson; Michael. Oaraci

    2002-01-01

    Greefihouse-induced warming and resulting shifts in climatic zones may exceed the migration capabilities of some species. We used fourteen combinations of General Circulation Models (GCMs) and Global Vegetation Models (GVMs) to investigate possible migration rates required under CO2 doubled climatic forcing.

  7. Mechanisms of initial heart rate response to postural change

    NARCIS (Netherlands)

    Borst, C.; Wieling, W.; van Brederode, J. F.; Hond, A.; de Rijk, L. G.; Dunning, A. J.

    1982-01-01

    We explored in 43 healthy subjects the afferent mechanisms of the initial heart rate response to standing by comparing free standing, 70 degrees head-up tilt, handgrip, and contraction of abdominal and leg muscles. The results indicate the following. 1) Standing evokes an immediate, large, bimodal

  8. 77 FR 64148 - Postal Rate and Classification Changes

    Science.gov (United States)

    2012-10-18

    .... Priority Mail International. Overall, Priority Mail International (PMI) prices increase by 15.1 percent. The existing price structure of PMI Flat Rate, Retail, Commercial Base, and Commercial Plus price.... Additionally, the Postal Service may offer a promotional discount or rebate on certain PMI items. International...

  9. Anomalous electric field changes and high flash rate beneath a ...

    Indian Academy of Sciences (India)

    In spite of many experimental and theoretical studies the relationships between storm dynamics, severe weather,and lightning activity have been least understood.Measurements of electric field made under a severe thunderstorm at a northeastern Indian station,Guwahati,India are reported. Lightning flash rate increases ...

  10. Spin current

    CERN Document Server

    Valenzuela, Sergio O; Saitoh, Eiji; Kimura, Takashi

    2017-01-01

    Since the discovery of the giant magnetoresistance effect in magnetic multilayers in 1988, a new branch of physics and technology, called spin-electronics or spintronics, has emerged, where the flow of electrical charge as well as the flow of electron spin, the so-called “spin current,” are manipulated and controlled together. The physics of magnetism and the application of spin current have progressed in tandem with the nanofabrication technology of magnets and the engineering of interfaces and thin films. This book aims to provide an introduction and guide to the new physics and applications of spin current, with an emphasis on the interaction between spin and charge currents in magnetic nanostructures.

  11. Absorption coefficient and refractive index changes of a quantum ring in the presence of spin-orbit couplings: Temperature and Zeeman effects

    Science.gov (United States)

    Zamani, A.; Azargoshasb, T.; Niknam, E.

    2017-10-01

    Effects of applied magnetic field, temperature and dimensions on the optical absorption coefficients (AC) and refractive index (RI) changes of a GaAs quantum ring are investigated in the presence of both Rashba and Dresselhaus spin-orbit interactions (SOI). To this end, the finite difference method (FDM) is used in order to numerically calculate the energy eigenvalues and eigenstates of the system while the compact density matrix approach is hired to calculate the optical properties. It is shown that application of magnetic field, temperature as well as the geometrical size in the presence of spin-orbit interactions, alter the electronic structure and consequently influence the linear and third-order nonlinear optical absorption coefficients as well as the refractive index changes of the system. Results show an obvious blue shift in optical curves with enhancing external magnetic field and temperature while the increment of dimensions result in red shift.

  12. Rate of coronary flow adaptation in response to changes in heart rate before and during anesthesia for coronary artery surgery

    NARCIS (Netherlands)

    van Wezel, H. B.; Kal, J. E.; Vergroesen, I.; Vroom, M. B.; de Graaf, R.; Dankelman, J.; Porsius, M.; Spaan, J. A.

    1996-01-01

    BACKGROUND: The rate of adaptation of coronary blood flow in response to stepwise changes in heart rate (HR) has been extensively studied in dogs and goats to improve our understanding of the dynamics of coronary regulation processes and their pathophysiology and to obtain time constants for

  13. Spin Electronics

    Science.gov (United States)

    2003-08-01

    applications, a ferromagnetic metal may be used as a source of spin-polarized electronics to be injected into a semiconductor, a superconductor or a...physical phenomena in II-VI and III-V semiconductors. In II-VI systems, the Mn2+ ions act to boost the electron spin precession up to terahertz ...conductors, proximity effect between ferromagnets and superconductors , and the effects of spin injection on the physical properties of the

  14. Spin doctoring

    OpenAIRE

    Vozková, Markéta

    2011-01-01

    1 ABSTRACT The aim of this text is to provide an analysis of the phenomenon of spin doctoring in the Euro-Atlantic area. Spin doctors are educated people in the fields of semiotics, cultural studies, public relations, political communication and especially familiar with the infrastructure and the functioning of the media industry. Critical reflection of manipulative communication techniques puts spin phenomenon in historical perspective and traces its practical use in today's social communica...

  15. 75 FR 69142 - Postal Rate and Classification Changes

    Science.gov (United States)

    2010-11-10

    .... Overall, Priority Mail International (PMI) prices increase on average by 3.8 percent. Classification... and for insurance with EMI and PMI increase. The unique price tier for Canada when optional insurance is purchased for PMI parcels is eliminated. Details of these changes may be found in the Attachment...

  16. Changing trends of indications and rate of cesarean section

    International Nuclear Information System (INIS)

    Ambreen, A.; Intsar, A.; Khurshid, S.

    2013-01-01

    Background: There is a trend of rising caesarean section rate over the past decade affecting the economy of the country. This continually rising caesarean section rate is of increasing concern to the health professionals and the public This study was designed to assess the indications and trends of caesarean sections done over a five year period from 2007 to 2011. Methods: This was a retrospective observational study done over a five year period in the department of Obstetrics and Gynaecology Fatima Memorial Hospital Lahore from 2007 to 2011. Results: Total no of deliveries from 2007 to 2011 were 30741 out of which caesarean sections performed were 13820.The caesarean birth rate increased from 41% to-48%. The indications varied a little in case of mal-presentation and eclampsia. APH and IUGR has risen a little from (from 2.56% to 2.6% and 1.83% to 2.34% respectively). But proportion of repeat caesarean section increased by 25.99% to 31.45% and that of presumed fetal distress increased from 8% to 15% respectively. Recently the indication of maternal choice is emerging with incidence of 0.8% in our study. The proportion has fallen in prolonged labour due to cervical dystocia from 17% to 14% and in obstructed labour from 4.6% to 3%. Conclusion: Individualization of every case, meticulous clinical examination, use of intrapartum fetomaternal survellience along with regular use of partograrm would limit the practice of undue caesarean sections. (author)

  17. ON THE INFERENCE OF THE COSMIC-RAY IONIZATION RATE ζ FROM THE HCO{sup +}-to-DCO{sup +} ABUNDANCE RATIO: THE EFFECT OF NUCLEAR SPIN

    Energy Technology Data Exchange (ETDEWEB)

    Shingledecker, Christopher N.; Le Gal, Romane; Hincelin, Ugo; Herbst, Eric [Department of Chemistry, University of Virginia, Charlottesville, VA 22904 (United States); Bergner, Jennifer B. [Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138 (United States); Öberg, Karin I., E-mail: shingledecker@virginia.edu [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)

    2016-10-20

    The chemistry of dense interstellar regions was analyzed using a time-dependent gas–grain astrochemical simulation and a new chemical network that incorporates deuterated chemistry, taking into account nuclear spin states for the hydrogen chemistry and its deuterated isotopologues. With this new network, the utility of the [HCO{sup +}]/[DCO{sup +}] abundance ratio as a probe of the cosmic-ray ionization rate has been re-examined, with special attention paid to the effect of the initial value of the ortho-to-para ratio (OPR) of molecular hydrogen. After discussing the use of the probe for cold cores, we compare our results with previous theoretical and observational results for a molecular cloud close to the supernova remnant W51C, which is thought to have an enhanced cosmic-ray ionization rate ζ caused by the nearby γ -ray source. In addition, we attempt to use our approach to estimate the cosmic-ray ionization rate for L1174, a dense core with an embedded star. Beyond the previously known sensitivity of [HCO{sup +}]/[DCO{sup +}] to ζ , we demonstrate its additional dependence on the initial OPR and, secondarily, on the age of the source, its temperature, and its density. We conclude that the usefulness of the [HCO{sup +}]/[DCO{sup +}] abundance ratio in constraining the cosmic-ray ionization rate in dense regions increases with the age of the source and the ionization rate as the ratio becomes far less sensitive to the initial value of the OPR.

  18. Changes in heart rate during third molar surgery.

    Science.gov (United States)

    Hollander, M H J; Schortinghuis, J; Vissink, A

    2016-12-01

    Anxiety is an undesirable psychological phenomenon. Patients are usually anxious when subjected to third molar surgery, but the pattern of anxiety is unknown. The aim of this study was to assess the intensity and course of anxiety during third molar surgery. This study included 48 consecutive patients (mean age 25±6 years) who had a third molar removed surgically under local anaesthesia. The heart rate was monitored continuously during treatment as a measure of anxiety. Preoperative anxiety was scored with the Modified Dental Anxiety Scale. Each patient's anxiety level was assessed when in the waiting room, sitting down in the dental chair, during the application of local anaesthesia, application of surgical drapes, time-out procedure, incision, alveolotomy, removal of the third molar, and suturing, and at the end of the procedure. The lowest heart rates were recorded in the waiting room, in the dental chair, during anaesthesia, when applying surgical drapes, during suturing, and at the end of the procedure. The highest values were obtained during the time-out procedure, incision, and alveolotomy (Pthird molar surgery, with the lowest levels of anxiety prior to surgery and directly postoperative and the highest during the time-out procedure and the actual surgery. Copyright © 2016 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  19. ECONOMETRIC APPROACH TO DIFFERENCE EQUATIONS MODELING OF EXCHANGE RATES CHANGES

    Directory of Open Access Journals (Sweden)

    Josip Arnerić

    2010-12-01

    Full Text Available Time series models that are commonly used in econometric modeling are autoregressive stochastic linear models (AR and models of moving averages (MA. Mentioned models by their structure are actually stochastic difference equations. Therefore, the objective of this paper is to estimate difference equations containing stochastic (random component. Estimated models of time series will be used to forecast observed data in the future. Namely, solutions of difference equations are closely related to conditions of stationary time series models. Based on the fact that volatility is time varying in high frequency data and that periods of high volatility tend to cluster, the most successful and popular models in modeling time varying volatility are GARCH type models and their variants. However, GARCH models will not be analyzed because the purpose of this research is to predict the value of the exchange rate in the levels within conditional mean equation and to determine whether the observed variable has a stable or explosive time path. Based on the estimated difference equation it will be examined whether Croatia is implementing a stable policy of exchange rates.

  20. Lung health and heart rate variability changes in salt workers.

    Science.gov (United States)

    Glad Mohesh, M I; Sundaramurthy, A

    2016-04-01

    India is the third largest salt producing country in the World, with a global annual production of 230 million tonnes. Large number of salt workers get employed in these salt milling plants risking their life from the effects of salt. Recent foreign evidences reported that these salt workers are exposed to aerosol salt particles that disturb their lung and cardiovascular autonomic control. To compare the status of lung health, cardiovascular autonomic control and biochemical changes in a group of salt industry workers with that of the age-matched normal subjects. Volunteers of both sexes (25-35 years) were divided into Group I (n=10) controls and Group II (n=10) non-brine salt workers in salt milling plants. From fasting blood sample, complete blood count, plasma electrolyte and lipid profile estimation were done. After resting for 15min, blood pressure and lead II ECG were recorded. Spirometry was done using RMS Helios spirometer. Data collected were later analysed using GraphPad Prism 5.0 with statistical significance set at p4.0, 112.8±1.7, pindustry has shown a little or no impact on the respiratory system, however there are changes in the blood and cardiovascular system, which need to be further studied to understand the long-term influences of salt in this population. Copyright © 2015 Tuberculosis Association of India. Published by Elsevier B.V. All rights reserved.

  1. Spin glasses

    CERN Document Server

    Bovier, Anton

    2007-01-01

    Spin glass theory is going through a stunning period of progress while finding exciting new applications in areas beyond theoretical physics, in particular in combinatorics and computer science. This collection of state-of-the-art review papers written by leading experts in the field covers the topic from a wide variety of angles. The topics covered are mean field spin glasses, including a pedagogical account of Talagrand's proof of the Parisi solution, short range spin glasses, emphasizing the open problem of the relevance of the mean-field theory for lattice models, and the dynamics of spin glasses, in particular the problem of ageing in mean field models. The book will serve as a concise introduction to the state of the art of spin glass theory, usefull to both graduate students and young researchers, as well as to anyone curious to know what is going on in this exciting area of mathematical physics.

  2. Spin-controlled atom-ion chemistry.

    Science.gov (United States)

    Sikorsky, Tomas; Meir, Ziv; Ben-Shlomi, Ruti; Akerman, Nitzan; Ozeri, Roee

    2018-03-02

    Quantum control of chemical reactions is an important goal in chemistry and physics. Ultracold chemical reactions are often controlled by preparing the reactants in specific quantum states. Here we demonstrate spin-controlled atom-ion inelastic (spin-exchange) processes and chemical (charge-exchange) reactions in an ultracold Rb-Sr + mixture. The ion's spin state is controlled by the atomic hyperfine spin state via spin-exchange collisions, which polarize the ion's spin parallel to the atomic spin. We achieve ~ 90% spin polarization due to the absence of strong spin-relaxation channel. Charge-exchange collisions involving electron transfer are only allowed for (RbSr) + colliding in the singlet manifold. Initializing the atoms in various spin states affects the overlap of the collision wave function with the singlet molecular manifold and therefore also the reaction rate. Our observations agree with theoretical predictions.

  3. 7 CFR 3575.80 - Interest rate changes after loan closing.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 15 2010-01-01 2010-01-01 false Interest rate changes after loan closing. 3575.80..., DEPARTMENT OF AGRICULTURE GENERAL Community Programs Guaranteed Loans § 3575.80 Interest rate changes after...) may collectively effect a permanent reduction in the interest rate on the guaranteed loan at any time...

  4. 47 CFR 43.43 - Reports of proposed changes in depreciation rates.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 3 2010-10-01 2010-10-01 false Reports of proposed changes in depreciation... Reports of proposed changes in depreciation rates. (a) Each communication common carrier with annual..., before making any changes in the depreciation rates applicable to its operated plant, file with the...

  5. 47 CFR 1.787 - Reports of proposed changes in depreciation rates.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Reports of proposed changes in depreciation... Reports and Requests § 1.787 Reports of proposed changes in depreciation rates. Carriers shall file reports regarding proposed changes in depreciation rates as required by part 43 of this chapter. ...

  6. Field metabolic rates of phytophagous bats: do pollination strategies of plants make life of nectar-feeders spin faster?

    Science.gov (United States)

    Voigt, Christian C; Kelm, Detlev H; Visser, G Henk

    2006-03-01

    Recently, it was argued that extrinsic factors, such as high foraging costs, lead to elevated field metabolic rates (FMR). We tested this suggestion by comparing the FMR of nectar-feeding and fruit-eating bats. We hypothesized that the foraging effort per energy reward is higher for nectar-feeding mammals than for fruit-eating mammals, since energy rewards at flowering plants are smaller than those at fruiting plants. Using the doubly labelled water method, we measured the FMR of nectar-feeding Glossophaga commissarisi and fruit-eating Carollia brevicauda, which coexisted in the same rainforest habitat and shared the same daytime roosts. Mass-specific FMR of G. commissarisi exceeded that of C. brevicauda by a factor of almost two: 5.3+/-0.6 kJ g(-1) day(-1) for G. commissarisi and 2.8+/-0.4 kJ g(-1) day(-1) for C. brevicauda. Since nectar-feeding bats imbibe nectar droplets of only 193 J energy content during each flower visit, a G. commissarisi bat has to perform several 100 flower visits per night to meet its energy requirement. The fruit-eating C. brevicauda, on the other hand, needs to harvest only 3-12 Piper infructescenses per night, as the energy reward per Piper equals ca. 6-30 kJ. We argue that the flowering and fruiting plants exert different selective forces on the foraging behaviour and energetics of pollinators and the seed dispersers, respectively. A comparison between nectar-feeding and non-nectar-feeding species in various vertebrate taxa demonstrates that pollinators have elevated FMRs.

  7. Choice with frequently changing food rates and food ratios.

    Science.gov (United States)

    Baum, William M; Davison, Michael

    2014-03-01

    In studies of operant choice, when one schedule of a concurrent pair is varied while the other is held constant, the constancy of the constant schedule may exert discriminative control over performance. In our earlier experiments, schedules varied reciprocally across components within sessions, so that while food ratio varied food rate remained constant. In the present experiment, we held one variable-interval (VI) schedule constant while varying the concurrent VI schedule within sessions. We studied five conditions, each with a different constant left VI schedule. On the right key, seven different VI schedules were presented in seven different unsignaled components. We analyzed performances at several different time scales. At the longest time scale, across conditions, behavior ratios varied with food ratios as would be expected from the generalized matching law. At shorter time scales, effects due to holding the left VI constant became more and more apparent, the shorter the time scale. In choice relations across components, preference for the left key leveled off as the right key became leaner. Interfood choice approximated strict matching for the varied right key, whereas interfood choice hardly varied at all for the constant left key. At the shortest time scale, visit patterns differed for the left and right keys. Much evidence indicated the development of a fix-and-sample pattern. In sum, the procedural difference made a large difference to performance, except for choice at the longest time scale and the fix-and-sample pattern at the shortest time scale. © Society for the Experimental Analysis of Behavior.

  8. Rates of change in climatic niches in plant and animal populations are much slower than projected climate change

    Science.gov (United States)

    Jezkova, Tereza

    2016-01-01

    Climate change may soon threaten much of global biodiversity. A critical question is: can species undergo niche shifts of sufficient speed and magnitude to persist within their current geographic ranges? Here, we analyse niche shifts among populations within 56 plant and animal species using time-calibrated trees from phylogeographic studies. Across 266 phylogeographic groups analysed, rates of niche change were much slower than rates of projected climate change (mean difference > 200 000-fold for temperature variables). Furthermore, the absolute niche divergence among populations was typically lower than the magnitude of projected climate change over the next approximately 55 years for relevant variables, suggesting the amount of change needed to persist may often be too great, even if these niche shifts were instantaneous. Rates were broadly similar between plants and animals, but especially rapid in some arthropods, birds and mammals. Rates for temperature variables were lower at lower latitudes, further suggesting that tropical species may be especially vulnerable to climate change. PMID:27881748

  9. Bias dependence of tunnel magnetoresistance in spin filtering tunnel junctions: Experiment and theory

    Science.gov (United States)

    Lüders, U.; Bibes, M.; Fusil, S.; Bouzehouane, K.; Jacquet, E.; Sommers, C. B.; Contour, J.-P.; Bobo, J.-F.; Barthélémy, A.; Fert, A.; Levy, P. M.

    2007-10-01

    A spin filter is a type of magnetic tunnel junction in which only one of the electrodes is magnetic and the insulating barrier is ferro- or ferrimagnetic. We report on spin-dependent transport measurements and their theoretical analysis in epitaxial spin filters integrating a tunnel barrier of the high-Curie-temperature ferrimagnetic spinel NiFe2O4 , with half-metallic La2/3Sr1/3MnO3 and Au electrodes. A positive tunnel magnetoresonance of up to ˜50% is obtained at low temperature, which we find decreases with bias voltage. In view of these experimental results, we propose a theoretical treatment of the transport properties of spin filters with epitaxial magnetic barriers, based on an elliptical variation of the decay rates within the spin-dependent gaps in analogy with what was calculated for nonmagnetic barrier materials such as MgO or SrTiO3 . Whereas the spin filtering efficiency for zero bias is of one sign, we show that this can easily change with bias; the degree of change hinges on the energy variation of the majority and minority spin decay rates of the transmission across the barrier. We point out some shortcomings of approaches based on models in which the transmission is related to spin-dependent barrier heights, and some implications for future experimental and theoretical research on spin filters.

  10. Magnus effects on spinning transonic missiles

    Science.gov (United States)

    Seginer, A.; Rosenwasser, I.

    1983-01-01

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

  11. Changes in Cesarean Delivery Rates by Gestational Age: United States, 1996-2011

    Science.gov (United States)

    ... the National Technical Information Service NCHS Changes in Cesarean Delivery Rates by Gestational Age: United States, 1996– ... origin, National Vital Statistics System The singleton birth cesarean delivery rate increased from 1998 to 2009 but ...

  12. Convergence of high order memory kernels in the Nakajima-Zwanzig generalized master equation and rate constants: Case study of the spin-boson model

    Science.gov (United States)

    Xu, Meng; Yan, Yaming; Liu, Yanying; Shi, Qiang

    2018-04-01

    The Nakajima-Zwanzig generalized master equation provides a formally exact framework to simulate quantum dynamics in condensed phases. Yet, the exact memory kernel is hard to obtain and calculations based on perturbative expansions are often employed. By using the spin-boson model as an example, we assess the convergence of high order memory kernels in the Nakajima-Zwanzig generalized master equation. The exact memory kernels are calculated by combining the hierarchical equation of motion approach and the Dyson expansion of the exact memory kernel. High order expansions of the memory kernels are obtained by extending our previous work to calculate perturbative expansions of open system quantum dynamics [M. Xu et al., J. Chem. Phys. 146, 064102 (2017)]. It is found that the high order expansions do not necessarily converge in certain parameter regimes where the exact kernel show a long memory time, especially in cases of slow bath, weak system-bath coupling, and low temperature. Effectiveness of the Padé and Landau-Zener resummation approaches is tested, and the convergence of higher order rate constants beyond Fermi's golden rule is investigated.

  13. Field Test Evaluation of Effect on Cone Resistance Caused by Change in Penetration Rate

    DEFF Research Database (Denmark)

    Poulsen, Rikke; Nielsen, Benjaminn Nordahl; Ibsen, Lars Bo

    2012-01-01

    This paper presents how a change in cone penetration rate affects the measured cone resistance during cone penetration testing in silty soils. Regardless of soil, type the standard rate of penetration is 20 mm/s and it is generally accepted that undrained penetration occurs in clay while drained...... in the laboratory. A change in the measured cone resistance occurs by lowering the penetration rate. This is caused by the changes in drainage conditions. Compared to the normal penetration rate of 20 mm/s, this paper illustrates that lowering the penetration rate leads to an increase in the cone resistance from 1...

  14. Genomics of adaptation depends on the rate of environmental change in experimental yeast populations

    NARCIS (Netherlands)

    Gorter, F.A.; Derks, M.F.L.; Heuvel, van den J.; Aarts, M.G.M.; Zwaan, B.J.; Ridder, de D.; Visser, de J.A.G.M.

    2017-01-01

    The rate of directional environmental change may have profound consequences for evolutionary dynamics and outcomes. Yet, most evolution experiments impose a sudden large change in the environment, after which the environment is kept constant. We previously cultured replicate Saccharomyces cerevisiae

  15. TOPICAL REVIEW: Spin current, spin accumulation and spin Hall effect

    Directory of Open Access Journals (Sweden)

    Saburo Takahashi and Sadamichi Maekawa

    2008-01-01

    Full Text Available Nonlocal spin transport in nanostructured devices with ferromagnetic injector (F1 and detector (F2 electrodes connected to a normal conductor (N is studied. We reveal how the spin transport depends on interface resistance, electrode resistance, spin polarization and spin diffusion length, and obtain the conditions for efficient spin injection, spin accumulation and spin current in the device. It is demonstrated that the spin Hall effect is caused by spin–orbit scattering in nonmagnetic conductors and gives rise to the conversion between spin and charge currents in a nonlocal device. A method of evaluating spin–orbit coupling in nonmagnetic metals is proposed.

  16. Spin electronics

    CERN Document Server

    Buhrman, Robert; Daughton, James; Molnár, Stephan; Roukes, Michael

    2004-01-01

    This report is a comparative review of spin electronics ("spintronics") research and development activities in the United States, Japan, and Western Europe conducted by a panel of leading U.S. experts in the field. It covers materials, fabrication and characterization of magnetic nanostructures, magnetism and spin control in magnetic nanostructures, magneto-optical properties of semiconductors, and magnetoelectronics and devices. The panel's conclusions are based on a literature review and a series of site visits to leading spin electronics research centers in Japan and Western Europe. The panel found that Japan is clearly the world leader in new material synthesis and characterization; it is also a leader in magneto-optical properties of semiconductor devices. Europe is strong in theory pertaining to spin electronics, including injection device structures such as tunneling devices, and band structure predictions of materials properties, and in development of magnetic semiconductors and semiconductor heterost...

  17. Spin glasses

    International Nuclear Information System (INIS)

    Fischer, K.H.; Hertz, J.A.

    1993-01-01

    Spin glasses, simply defined by the authors as a collection of spins (i.e., magnetic moments) whose low-temperature state is a frozen disordered one, represent one of the fascinating new fields of study in condensed matter physics, and this book is the first to offer a comprehensive account of the subject. Included are discussions of the most important developments in theory, experimental work, and computer modeling of spin glasses, all of which have taken place essentially within the last two decades. The first part of the book gives a general introduction to the basic concepts and a discussion of mean field theory, while the second half concentrates on experimental results, scaling theory, and computer simulation of the structure of spin glasses

  18. Spin force and torque in non-relativistic Dirac oscillator on a sphere

    Science.gov (United States)

    Shikakhwa, M. S.

    2018-03-01

    The spin force operator on a non-relativistic Dirac oscillator (in the non-relativistic limit the Dirac oscillator is a spin one-half 3D harmonic oscillator with strong spin-orbit interaction) is derived using the Heisenberg equations of motion and is seen to be formally similar to the force by the electromagnetic field on a moving charged particle. When confined to a sphere of radius R, it is shown that the Hamiltonian of this non-relativistic oscillator can be expressed as a mere kinetic energy operator with an anomalous part. As a result, the power by the spin force and torque operators in this case are seen to vanish. The spin force operator on the sphere is calculated explicitly and its torque is shown to be equal to the rate of change of the kinetic orbital angular momentum operator, again with an anomalous part. This, along with the conservation of the total angular momentum, suggests that the spin force exerts a spin-dependent torque on the kinetic orbital angular momentum operator in order to conserve total angular momentum. The presence of an anomalous spin part in the kinetic orbital angular momentum operator gives rise to an oscillatory behavior similar to the Zitterbewegung. It is suggested that the underlying physics that gives rise to the spin force and the Zitterbewegung is one and the same in NRDO and in systems that manifest spin Hall effect.

  19. Episodic Spin-up and Spin-down Torque on Earth

    Science.gov (United States)

    Slabinski, Victor J.; Mendonca, Antonio A.

    2018-04-01

    Variations in Earth rotation angle are traditionally expressed by the time difference (ΔT=TT-UT1) between Terrestrial Time (TT) as told by atomic clocks and Universal Time UT1, the time variable used by the Earth-rotation formula. A plot of ΔT versus TT over the past 160 years shows a continuous curve with approximate straight-line segments with different spans of order ~20 years. Removing the tidal and seasonal variations from the data gives these line segments which represent the “decadal variations” in Earth rotation.The slope of a straight-line segment is proportional to the departure of Earth rotation rate from a reference value at the time. The change in slope over the relatively short time between segments indicates an episodic spin-up or spin-down in Earth rotation. The daily combination of VLBI, SLR, and other modern data available since 1973 gives us accurate, daily values of ΔT and the corresponding LOD (Length Of Day) values during these episodes. These allow us to determine the rotational acceleration occurring then.The three largest spin-speed changes found during the VLBI era have the following characteristics:Episode _____________ Duration__ ΔLOD__LOD Rate1983 Dec 30-1984 Jan 28 ... 29 d ...-0.65 ms ..-8.3 ms/y ..........spin-up1989 Mar 15-1989 May 23 ...69 d ....0.68 .......+3.6 ..............spin-down1994 Jan 21-2001 Apr 01 ... 6.5 y ...-2.2 .........-0.36 ..extended spin-upFor the first two episodes listed, we find the acceleration grows from zero (or at least a relatively small value) to its extreme value in ~1 day, stays approximately constant at this value for 29 or 69 days, and then decays back to zero over ~1 day. The acceleration, while it occurs, gives an LOD rate much greater than the 0.02 ms/y rate from tidal friction.The third episode shows that occasionally a several-year-long episode occurs. The acceleration magnitude is smaller but can make a larger total change in LOD (and spin rate). Tidal friction requires >100 y to equal

  20. A multiple dating approach (luminescence and electron spin resonance) to assess rates of crustal deformation using Quaternary fluvial terraces of the lower Moulouya River (NE Morocco)

    Science.gov (United States)

    Bartz, Melanie; Rixhon, Gilles; Duval, Mathieu; King, Georgina; Brückner, Helmut

    2017-04-01

    40 and MIS 32, whilst the last terrace formation in the hanging wall is dated between 1.19±0.11 and 1.61±0.15 Ma, indicating even older fluvial deposition. This study shows the high potential of the multiple centre approach in ESR dating, especially when dealing with samples beyond the dating range of luminescence techniques. Nevertheless, independent age control is still required to evaluate the reliability of the ESR dating results; this will be achieved in the near future using palaeomagnetism (CENIEH, Burgos) and isochron burial dating (26Al/10Be) on the same deposits. The acquisition of a reliable chronological framework based on different techniques will eventually give new insights into the rate of Quaternary crustal deformation in this region of Morocco. References: Barcos, L., Jabaloy, A., Azdimousa, A., Asebriy, L., Gómez-Ortiz, D., Rodríguez-Peces, M.J., Tejero, R., Pérez-Peña, J.V., 2014. Study of relief changes related to active doming in the eastern Moroccan Rif (Morocco) using geomorphological indices. J. African Earth Sci. 100, 493-509. Duval, M., Sancho, C., Calle, M., Guilarte, V., Penna-Monné, J.L., 2015. On the interest of using the multiple centre approach in ESR dating of optically bleached quartz grains: Some examples from the Early Pleistocene terraces of the Alcanadre River (Ebro basin, Spain). Quat. Geochr. 29, 58-69. Huntley, 2006. An explanation of the power-law decay of luminescence. Journal of Physics: Condensed Matter 18, 1359-1365. Kars, R.H., Wallinga, J., Cohen, K.M., 2008. A new approach towards anomalous fading correction for feldspar IRSL dating - tests on samples in field saturation. Radiation Measurements 43, 786-790. Rixhon, G., Bartz, M., El Ouahabi, M., Szemkus, N., Brückner, H., 2017, Contrasting terrace systems of the lower Moulouya river as indicator of crustal deformation in NE Morocco. J. African Earth Sci. 126, 45-47.

  1. 47 CFR 76.1603 - Customer service-rate and service changes.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false Customer service-rate and service changes. 76... SERVICES MULTICHANNEL VIDEO AND CABLE TELEVISION SERVICE Notices § 76.1603 Customer service—rate and service changes. (a) A cable franchise authority may enforce the customer service standards set forth in...

  2. Keeping up with a warming world; assessing the rate of adaptation to climate change

    NARCIS (Netherlands)

    Visser, M.E.

    2008-01-01

    The pivotal question in the debate on the ecological effects of climate change is whether species will be able to adapt fast enough to keep up with their changing environment. If we establish the maximal rate of adaptation, this will set an upper limit to the rate at which temperatures can increase

  3. Interactions between rates of temperature change and acclimation affect latitudinal patterns of warming tolerance.

    Science.gov (United States)

    Allen, Jessica L; Chown, Steven L; Janion-Scheepers, Charlene; Clusella-Trullas, Susana

    2016-01-01

    Critical thermal limits form an increasing component of the estimation of impacts of global change on ectotherms. Whether any consistent patterns exist in the interactive effects of rates of temperature change (or experimental ramping rates) and acclimation on critical thermal limits and warming tolerance (one way of assessing sensitivity to climate change) is, however, far from clear. Here, we examine the interacting effects of ramping rate and acclimation on the critical thermal maxima (CTmax) and minima (CTmin) and warming tolerance of six species of springtails from sub-tropical, temperate and polar regions. We also provide microhabitat temperatures from 26 sites spanning 5 years in order to benchmark environmentally relevant rates of temperature change. Ramping rate has larger effects than acclimation on CTmax, but the converse is true for CTmin. Responses to rate and acclimation effects are more consistent among species for CTmax than for CTmin. In the latter case, interactions among ramping rate and acclimation are typical of polar species, less marked for temperate ones, and reduced in species from the sub-tropics. Ramping rate and acclimation have substantial effects on estimates of warming tolerance, with the former being more marked. At the fastest ramping rates (>1.0°C/min), tropical species have estimated warming tolerances similar to their temperate counterparts, whereas at slow ramping rates (warming tolerance is much reduced in tropical species. Rates of temperate change in microhabitats relevant to the springtails are typically warming tolerance approach.

  4. 7 CFR 1951.241 - Special provision for interest rate change.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 14 2010-01-01 2009-01-01 true Special provision for interest rate change. 1951.241... Community and Direct Business Programs Loans and Grants § 1951.241 Special provision for interest rate... interest rate charged by FmHA or its successor agency under Public Law 103-354 to water and waste disposal...

  5. 75 FR 82066 - Change in Discount Rate for Water Resources Planning

    Science.gov (United States)

    2010-12-29

    ... Doc No: 2010-32801] DEPARTMENT OF THE INTERIOR Bureau of Reclamation Change in Discount Rate for Water... determination of a discount rate for Federal water resources planning. The discount rate for Federal water resources planning for fiscal year 2011 is 4.125 percent. Discounting is to be used to convert future...

  6. 75 FR 8106 - Change in Discount Rate for Water Resources Planning

    Science.gov (United States)

    2010-02-23

    ... Bureau of Reclamation Change in Discount Rate for Water Resources Planning AGENCY: Bureau of Reclamation... Resources Development Act of 1974 require an annual determination of a discount rate for Federal water resources planning. The discount rate for Federal water resources planning for fiscal year 2010 is 4.375...

  7. 76 FR 73674 - Change in Discount Rate for Water Resources Planning

    Science.gov (United States)

    2011-11-29

    ... Bureau of Reclamation Change in Discount Rate for Water Resources Planning AGENCY: Bureau of Reclamation... Resources Development Act of 1974 require an annual determination of a discount rate for Federal water resources planning. The discount rate for Federal water resources planning for fiscal year 2012 is 4 percent...

  8. 78 FR 16706 - Change in Discount Rate for Water Resources Planning

    Science.gov (United States)

    2013-03-18

    ... Bureau of Reclamation Change in Discount Rate for Water Resources Planning AGENCY: Bureau of Reclamation... Resources Development Act of 1974 require an annual determination of a discount rate for Federal water resources planning. The discount rate for Federal water resources planning for fiscal year 2013 is 3.75...

  9. 78 FR 67393 - Change in Discount Rate for Water Resources Planning

    Science.gov (United States)

    2013-11-12

    ... Bureau of Reclamation Change in Discount Rate for Water Resources Planning AGENCY: Bureau of Reclamation... Resources Development Act of 1974 require an annual determination of a discount rate for Federal water resources planning. The discount rate for Federal water resources planning for fiscal year 2014 is 3.50...

  10. Changes in total death rate and in ischaemic heart disease death ...

    African Journals Online (AJOL)

    Changes in total death rate and in ischaemic heart disease death rate in interethnic South African populations, 1978 - 1989. ... While knowledge of the reasons for the rises and falls in IHD rates reInains incomplete, whites have none the less taken some preventive action, although Asians and coloureds apparently little.

  11. Day-night variation in heart rate variability changes induced by endotoxaemia in healthy volunteers

    DEFF Research Database (Denmark)

    Alamili, M.; Rosenberg, J; Gögenur, I

    2015-01-01

    and parasympathetic activity can be estimated by measuring heart rate variability (HRV). Based on the intimate link between ANS and the inflammatory response, we hypothesized, that HRV changes seen during endotoxaemia would be different based on time of the day the endotoxaemia is initiated. We investigated day....../HF and mean heart rate significantly increased by endotoxaemia (Pheart rate (P

  12. Rating

    OpenAIRE

    Karas, Vladimír

    2006-01-01

    Charakteristika ratingu. Dělení a druhy ratingu (rating emise × rating emitenta; dlouhodobý rating × krátkodobý rating; mezinárodní rating × lokální rating). Obecné požadavky kladené na rating. Proces tvorby ratingu. Vyžádaný rating. Nevyžádaný rating. Ratingový proces na bázi volně přístupných informací. Uplatňované ratingové systémy. Ratingová kriteria. Využití a interpretace ratingové známky. Funkce ratingu. Rating v souvislosti s BASEL II. Rating v souvislosti s hospodářskými krizemi....

  13. Examining the reaction of monetary policy to exchange rate changes: A nonlinear ARDL approach

    Science.gov (United States)

    Manogaran, Lavaneesvari; Sek, Siok Kun

    2017-04-01

    Previous studies showed the exchange rate changes can have significant impacts on macroeconomic performance. Over fluctuation of exchange rate may lead to economic instability. Hence, monetary policy rule tends to react to exchange rate changes. Especially, in emerging economies where the policy-maker tends to limit the exchange rate movement through interventions. In this study, we seek to investigate how the monetary policy rule reacts to exchange rate changes. The nonlinear autoregressive distributed lag (NARDL) model is applied to capture the asymmetric effect of exchange rate changes on monetary policy reaction function (interest rate). We focus the study in ASEAN5 countries (Indonesia, Malaysia, Philippines, Thailand and Singapore). The results indicated the existence of asymmetric effect of exchange rates changes on the monetary reaction function for all ASEAN5 countries in the long-run. Where, in majority of the cases the monetary policy is reacting to the appreciation and depreciation of exchange rate by raising the policy rate. This affirms the intervention of policymakers with the `fear of floating' behavior.

  14. The spin lattice relaxation of 8Li in simple metals

    Science.gov (United States)

    Hossain, M. D.; Saadaoui, H.; Parolin, T. J.; Song, Q.; Wang, D.; Smadella, M.; Chow, K. H.; Egilmez, M.; Fan, I.; Kiefl, R. F.; Kreitzman, S. R.; Levy, C. D. P.; Morris, G. D.; Pearson, M. R.; Salman, Z.; MacFarlane, W. A.

    2009-04-01

    We report the modification to the linear temperature dependence of the Korringa nuclear spin-lattice relaxation rate of an implanted NMR probe in silver, as it makes a thermally activated site change. We develop a simple model of this phenomenon, which is found in a number of metals including Au and Nb.

  15. Resonance of about-weekly human heart rate rhythm with solar activity change.

    Science.gov (United States)

    Cornelissen, G; Halberg, F; Wendt, H W; Bingham, C; Sothern, R B; Haus, E; Kleitman, E; Kleitman, N; Revilla, M A; Revilla, M; Breus, T K; Pimenov, K; Grigoriev, A E; Mitish, M D; Yatsyk, G V; Syutkina, E V

    1996-12-01

    In several human adults, certain solar activity rhythms may influence an about 7-day rhythm in heart rate. When no about-weekly feature was found in the rate of change in sunspot area, a measure of solar activity, the double amplitude of a circadian heart rate rhythm, approximated by the fit of a 7-day cosine curve, was lower, as was heart rate corresponds to about-weekly features in solar activity and/or relates to a sunspot cycle.

  16. Cross relaxation in nitroxide spin labels

    DEFF Research Database (Denmark)

    Marsh, Derek

    2016-01-01

    Cross relaxation, and mI-dependence of the intrinsic electron spin-lattice relaxation rate We, are incorporated explicitly into the rate equations for the electron-spin population differences that govern the saturation behaviour of 14N- and 15N-nitroxide spin labels. Both prove important in spin......-label EPR and ELDOR, particularly for saturation recovery studies. Neither for saturation recovery, nor for CW-saturation EPR and CW-ELDOR, can cross relaxation be described simply by increasing the value of We, the intrinsic spin-lattice relaxation rate. Independence of the saturation recovery rates from...... the hyperfine line pumped or observed follows directly from solution of the rate equations including cross relaxation, even when the intrinsic spin-lattice relaxation rate We is mI-dependent....

  17. Spin gating electrical current

    Science.gov (United States)

    Ciccarelli, C.; Zârbo, L. P.; Irvine, A. C.; Campion, R. P.; Gallagher, B. L.; Wunderlich, J.; Jungwirth, T.; Ferguson, A. J.

    2012-09-01

    The level of the chemical potential is a fundamental parameter of the electronic structure of a physical system, which consequently plays an important role in defining the properties of active electrical devices. We directly measure the chemical potential shift in the relativistic band structure of the ferromagnetic semiconductor (Ga,Mn)As, controlled by changes in its magnetic order parameter. Our device comprises a non-magnetic aluminum single electron channel capacitively coupled to the (Ga,Mn)As gate electrode. The chemical potential shifts of the gate are directly read out from the shifts in the Coulomb blockade oscillations of the single electron transistor. The experiments introduce a concept of spin gating electrical current. In our spin transistor spin manipulation is completely removed from the electrical current carrying channel.

  18. Evolution of Spin, Orbital, and Superorbital Modulations of 4U 0114+650

    Science.gov (United States)

    Hu, Chin-Ping; Chou, Yi; Ng, C.-Y.; Lin, Lupin Chun-Che; Yen, David Chien-Chang

    2017-07-01

    We report a systematic analysis of the spin, orbital, and superorbital modulations of 4U 0114+650, a high-mass X-ray binary that consists of one of the slowest spinning neutron stars. Using the dynamic power spectrum, we found that the spin period varied dramatically and is anticorrelated with the long-term X-ray flux variation that can be observed using the Rossi X-ray Timing Explorer ASM, Swift BAT, and the Monitor of All-sky X-ray Image. The spin-up rate over the entire data set is consistent with previously reported values; however, the local spin-up rate is considerably higher. The corresponding local spin-up timescale is comparable to the local spin-up rate of OAO 1657-415, indicating that 4U 0114+650 could also have a transient disk. Moreover, the spin period evolution shows two ˜1000-day spin-down/random-walk epochs that appeared together with depressions of the superorbital modulation amplitude. This implies that the superorbital modulation was closely related to the presence of the accretion disk, which is not favored in the spin-down/random-walk epochs because the accretion is dominated by the direct wind accretion. The orbital period is stable during the entire time span; however, the orbital profile significantly changes with time. We found that the depth of the dip near the inferior conjunction of the companion is highly variable, which disfavors the eclipsing scenario. Moreover, the dip was less obvious during the spin-down/random-walk epochs, indicating its correlation with the accretion disk. Further monitoring in both X-ray and optical bands could reveal the establishment of the accretion disk in this system.

  19. Evolution of Spin, Orbital, and Superorbital Modulations of 4U 0114+650

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Chin-Ping; Ng, C.-Y. [Department of Physics, The University of Hong Kong, Pokfulam Road (Hong Kong); Chou, Yi [Graduate Institute of Astronomy, National Central University, Jhongli 32001, Taiwan (China); Lin, Lupin Chun-Che [Institute of Astronomy and Astrophysics, Academia Sinica, Taiwan (China); Yen, David Chien-Chang, E-mail: cphu@hku.hk [Department of Mathematics, Fu Jen Catholic University, New Taipei City 24205, Taiwan (China)

    2017-07-20

    We report a systematic analysis of the spin, orbital, and superorbital modulations of 4U 0114+650, a high-mass X-ray binary that consists of one of the slowest spinning neutron stars. Using the dynamic power spectrum, we found that the spin period varied dramatically and is anticorrelated with the long-term X-ray flux variation that can be observed using the Rossi X-ray Timing Explorer ASM, Swift BAT, and the Monitor of All-sky X-ray Image. The spin-up rate over the entire data set is consistent with previously reported values; however, the local spin-up rate is considerably higher. The corresponding local spin-up timescale is comparable to the local spin-up rate of OAO 1657−415, indicating that 4U 0114+650 could also have a transient disk. Moreover, the spin period evolution shows two ∼1000-day spin-down/random-walk epochs that appeared together with depressions of the superorbital modulation amplitude. This implies that the superorbital modulation was closely related to the presence of the accretion disk, which is not favored in the spin-down/random-walk epochs because the accretion is dominated by the direct wind accretion. The orbital period is stable during the entire time span; however, the orbital profile significantly changes with time. We found that the depth of the dip near the inferior conjunction of the companion is highly variable, which disfavors the eclipsing scenario. Moreover, the dip was less obvious during the spin-down/random-walk epochs, indicating its correlation with the accretion disk. Further monitoring in both X-ray and optical bands could reveal the establishment of the accretion disk in this system.

  20. Interference Spins

    DEFF Research Database (Denmark)

    Popovski, Petar; Simeone, Osvaldo; Nielsen, Jimmy Jessen

    2015-01-01

    on traffic load and interference condition leads to performance gains. In this letter, a general network of multiple interfering two-way links is studied under the assumption of a balanced load in the two directions for each link. Using the notion of interference spin, we introduce an algebraic framework...

  1. Spinning worlds

    NARCIS (Netherlands)

    Schwarz, H.

    2017-01-01

    The thesis "Spinning Worlds" is about the characterisation of two types of gas-giant exoplanets: Hot Jupiters, with orbital periods of fewer than five days, and young, wide-orbit gas giants, with orbital periods as long as thousands of years. The thesis is based on near-infrared observations of 1

  2. Maximum rates of climate change are systematically underestimated in the geological record.

    Science.gov (United States)

    Kemp, David B; Eichenseer, Kilian; Kiessling, Wolfgang

    2015-11-10

    Recently observed rates of environmental change are typically much higher than those inferred for the geological past. At the same time, the magnitudes of ancient changes were often substantially greater than those established in recent history. The most pertinent disparity, however, between recent and geological rates is the timespan over which the rates are measured, which typically differ by several orders of magnitude. Here we show that rates of marked temperature changes inferred from proxy data in Earth history scale with measurement timespan as an approximate power law across nearly six orders of magnitude (10(2) to >10(7) years). This scaling reveals how climate signals measured in the geological record alias transient variability, even during the most pronounced climatic perturbations of the Phanerozoic. Our findings indicate that the true attainable pace of climate change on timescales of greatest societal relevance is underestimated in geological archives.

  3. New England observed and predicted August stream/river temperature maximum daily rate of change points

    Data.gov (United States)

    U.S. Environmental Protection Agency — The shapefile contains points with associated observed and predicted August stream/river temperature maximum negative rate of change in New England based on a...

  4. The Impact of Credit Rating Changes in Latin American Stock Markets

    Directory of Open Access Journals (Sweden)

    Abner de Pinho Nogueira Freitas

    2013-10-01

    Full Text Available Our objective is to examine whether a rating change or Credit Watch announcement has a significant impact on Latin American stock prices. We conducted an event study to analyze stock market reaction to such news in the four major Latin American economies: Argentina, Brazil, Chile and Mexico. We find similar results to thosepreviously observed in the literature, wherein the impact is quite significant for rating downgrades but less relevant for rating upgrades and Credit Watches. We also run cross section regressions to investigate which variables best explain the impact rating changes announcements have on stock prices in these countries. The results indicate that the most significant variable is the absolute change in the number of notches for downgrades. We conclude that credit ratings are relevant information in Latin America.

  5. Reinforcer magnitude and rate dependency: evaluation of resistance-to-change mechanisms.

    Science.gov (United States)

    Pinkston, Jonathan W; Ginsburg, Brett C; Lamb, Richard J

    2014-10-01

    Under many circumstances, reinforcer magnitude appears to modulate the rate-dependent effects of drugs such that when schedules arrange for relatively larger reinforcer magnitudes rate dependency is attenuated compared with behavior maintained by smaller magnitudes. The current literature on resistance to change suggests that increased reinforcer density strengthens operant behavior, and such strengthening effects appear to extend to the temporal control of behavior. As rate dependency may be understood as a loss of temporal control, the effects of reinforcer magnitude on rate dependency may be due to increased resistance to disruption of temporally controlled behavior. In the present experiments, pigeons earned different magnitudes of grain during signaled components of a multiple FI schedule. Three drugs, clonidine, haloperidol, and morphine, were examined. All three decreased overall rates of key pecking; however, only the effects of clonidine were attenuated as reinforcer magnitude increased. An analysis of within-interval performance found rate-dependent effects for clonidine and morphine; however, these effects were not modulated by reinforcer magnitude. In addition, we included prefeeding and extinction conditions, standard tests used to measure resistance to change. In general, rate-decreasing effects of prefeeding and extinction were attenuated by increasing reinforcer magnitudes. Rate-dependent analyses of prefeeding showed rate-dependency following those tests, but in no case were these effects modulated by reinforcer magnitude. The results suggest that a resistance-to-change interpretation of the effects of reinforcer magnitude on rate dependency is not viable.

  6. Biomass is the main driver of changes in ecosystem process rates during tropical forest succession

    NARCIS (Netherlands)

    Lohbeck, M.W.M.; Poorter, L.; Martinez-Ramos, M.; Bongers, F.

    2015-01-01

    Over half of the world's forests are disturbed, and the rate at which ecosystem processes recover after disturbance is important for the services these forests can provide. We analyze the drivers' underlying changes in rates of key ecosystem processes (biomass productivity, litter productivity,

  7. Embryonic development rates of northern grasshoppers (Orthoptera: Acrididae): implications for climate change and habitat management

    Science.gov (United States)

    Temperature-dependent rates of embryonic development are a primary determinant of the life cycle of many species of grasshoppers which, in cold climates, spend two winters in the egg stage. Knowledge of embryonic developmental rates is important for an assessment of the effects of climate change and...

  8. Spatial stabilization and intensification of moistening and drying rate patterns under future climate change

    Science.gov (United States)

    Chavaillaz, Yann; Joussaume, Sylvie; Bony, Sandrine; Braconnot, Pascale

    2016-08-01

    Precipitation projections are usually presented as the change in precipitation between a fixed current baseline and a particular time in the future. However, upcoming generations will be affected in a way probably more related to the moving trend in precipitation patterns, i.e. to the rate and the persistence of regional precipitation changes from one generation to the next, than to changes relative to a fixed current baseline. In this perspective, we propose an alternative characterization of the future precipitation changes predicted by general circulation models, focusing on the precipitation difference between two subsequent 20-year periods. We show that in a business-as-usual emission pathway, the moistening and drying rates increase by 30-40 %, both over land and ocean. As we move further over the twenty-first century, more regions exhibit a significant rate of precipitation change, while the patterns become geographically stationary and the trends persistent. The stabilization of the geographical rate patterns that occurs despite the acceleration of global warming can be physically explained: it results from the increasing contribution of thermodynamic processes compared to dynamic processes in the control of precipitation change. We show that such an evolution is already noticeable over the last decades, and that it could be reversed if strong mitigation policies were quickly implemented. The combination of intensification and increasing persistence of precipitation rate patterns may affect the way human societies and natural ecosystems adapt to climate change, especially in the Mediterranean basin, in Central America, in South Asia and in the Arctic.

  9. Digital operation and eye diagrams in spin-lasers

    International Nuclear Information System (INIS)

    Wasner, Evan; Bearden, Sean; Žutić, Igor; Lee, Jeongsu

    2015-01-01

    Digital operation of lasers with injected spin-polarized carriers provides an improved operation over their conventional counterparts with spin-unpolarized carriers. Such spin-lasers can attain much higher bit rates, crucial for optical communication systems. The overall quality of a digital signal in these two types of lasers is compared using eye diagrams and quantified by improved Q-factors and bit-error-rates in spin-lasers. Surprisingly, an optimal performance of spin-lasers requires finite, not infinite, spin-relaxation times, giving a guidance for the design of future spin-lasers

  10. A Model of Target Changes and the Term Structure of Interest Rates

    OpenAIRE

    Pierluigi Balduzzi; Giuseppe Bertola; Silverio Foresi

    1993-01-01

    We explore the effects of official targeting policy on the term-structure of nominal interest rates, adapting relevant insights from theoretical work on "peso problems" to account for realistic infrequency of target changes. Our analysis of daily U.S. interest rates and newly available historical targets provides an interpretation for persistent spreads between short-term money-market rates and overnight fed-funds targets, and for the poor performance of expectations-hypothesis tests: it is t...

  11. Growth rate change driven by external perturbation in the azuki bean weevil

    CERN Document Server

    Fukano, T

    2003-01-01

    In laboratory experiments we obtain that the apparent growth rate of the population becomes larger than one under the normal condition, triggered by the external perturbation as the removal of individuals. The changed growth rate is stable for a while. We also propose a simple model of population dynamics allowing both matching and mis-matching the trend of the external perturbation, and show that the growth rate of the model population is changeable and stable to some extent.

  12. Fast Electrical Control of Single Electron Spins in Quantum Dots with Vanishing Influence from Nuclear Spins

    Science.gov (United States)

    Yoneda, J.; Otsuka, T.; Nakajima, T.; Takakura, T.; Obata, T.; Pioro-Ladrière, M.; Lu, H.; Palmstrøm, C. J.; Gossard, A. C.; Tarucha, S.

    2014-12-01

    We demonstrate fast universal electrical spin manipulation with inhomogeneous magnetic fields. With fast Rabi frequency up to 127 MHz, we leave the conventional regime of strong nuclear-spin influence and observe a spin-flip fidelity >96 % , a distinct chevron Rabi pattern in the spectral-time domain, and a spin resonance linewidth limited by the Rabi frequency, not by the dephasing rate. In addition, we establish fast z rotations up to 54 MHz by directly controlling the spin phase. Our findings will significantly facilitate tomography and error correction with electron spins in quantum dots.

  13. Dynamics of spin-flip photon-assisted tunneling

    NARCIS (Netherlands)

    Braakman, F.R.; Danon, J.; Schreiber, L.R.; Wegscheider, W.; Vandersypen, L.M.K.

    2014-01-01

    We present time-resolved measurements of spin-flip photon-assisted tunneling and spin-flip relaxation in a doubly occupied double quantum dot. The photon-assisted excitation rate as a function of magnetic field indicates that spin-orbit coupling is the dominant mechanism behind the spin-flip under

  14. A prospective study of the association between weight changes and self-rated health

    DEFF Research Database (Denmark)

    Simonsen, Mette K; Hundrup, Yrsa A; Grønbaek, Morten

    2008-01-01

    Obesity and self-rated health (SRH) are strong predictors of morbidity and mortality but their interrelation is sparsely studied. The aim of this study was to analyse the association between weight changes and changes in SRH among women. We also examined if poor SRH at baseline was associated...... with later weight gain....

  15. Rates of change in tree communities of secondary Neotropical forests following major disturbances

    NARCIS (Netherlands)

    Chazdon, R.L.; Letcher, S.G.; Breugel, van M.; Martínez-Ramos, M.; Bongers, F.J.J.M.; Finegan, B.

    2007-01-01

    Rates of change in tree communities following major disturbances are determined by a complex set of interactions between local site factors, landscape history and structure, regional species pools and species life histories. Our analysis focuses on vegetation change following abandonment of

  16. Estimating the rates of mass change, ice volume change and snow volume change in Greenland from ICESat and GRACE data

    NARCIS (Netherlands)

    Slobbe, D.C.; Ditmar, P.G.; Lindenbergh, R.C.

    2008-01-01

    The focus of this paper is on the quantification of ongoing mass and volume changes over the Greenland ice sheet. For that purpose, we used elevation changes derived from the Ice, Cloud, and land Elevation Satellite (ICESat) laser altimetry mission and monthly variations of the Earth’s gravity field

  17. Nuclear spin relaxation of methane in solid xenon

    Science.gov (United States)

    Sugimoto, Takeru; Arakawa, Ichiro; Yamakawa, Koichiro

    2018-03-01

    Nuclear spin relaxation of methane in solid xenon has been studied by infrared spectroscopy. From the analysis of the temporal changes of the rovibrational peaks, the rates of the nuclear spin relaxation of I = 2 ← 1 correlated to the rotational relaxation of J = 0 ← 1 were obtained at temperatures of 5.1-11.5 K. On the basis of the temperature dependence of the relaxation rate, the activation energy of the indirect two-phonon process was determined to be 50 ± 6 K, which is in good agreement with the rotational transition energies of J = 2 ← 1 and J = 3 ← 1. Taking into account this result and the spin degeneracy, we argue that the lowest J = 3 level in which the I = 1 and I = 2 states are degenerate acts as the intermediate point of the indirect process.

  18. Detecting When "Quality of Life" Has Been "Enhanced": Estimating Change in Quality of Life Ratings.

    Science.gov (United States)

    Tractenberg, Rochelle E; Yumoto, Futoshi; Aisen, Paul S

    2013-11-01

    To demonstrate challenges in the estimation of change in quality of life (QOL). Data were taken from a completed clinical trial with negative results. Responses to 13 QOL items were obtained 12 months apart from 258 persons with Alzheimer's disease (AD) participating in a randomized, placebo-controlled clinical trial with two treatment arms. Two analyses to estimate whether "change" in QOL occurred over 12 months are described. A simple difference (later - earlier) was calculated from total scores (standard approach). A Qualified Change algorithm (novel approach) was applied to each item: differences in ratings were classified as either: improved, worsened, stayed poor, or stayed "positive" (fair, good, excellent). The strengths of evidence supporting a claim that "QOL changed", derived from the two analyses, were compared by considering plausible alternative explanations for, and interpretations of, results obtained under each approach. Total score approach: QOL total scores decreased, on average, in the two treatment (both -1.0, p 0.3) groups. Qualified change approach: Roughly 60% of all change in QOL items was worsening in every arm; 17% - 42% of all subjects experienced change in each item. Totalling the subjective QOL item ratings collapses over items, and suggests a potentially misleading "overall" level of change (or no change, as in the placebo arm). Leaving the items as individual components of "quality" of life they were intended to capture, and qualifying the direction and amount of change in each, suggests that at least 17% of any group experienced change on every item, with 60% of all observed change being worsening. Summarizing QOL item ratings as a total "score" collapses over the face-valid, multi-dimensional components of the construct "quality of life". Qualified Change provides robust evidence of changes to QOL or "enhancements of" life quality.

  19. NV-NV electron-electron spin and NV-N S electron - electron and electron-nuclear spin interaction in diamond

    Science.gov (United States)

    Armstrong, Seiji; Rogers, Lachlan J.; McMurtrie, Roger L.; Manson, Neil B.

    2010-02-01

    Features associated with the cross relaxation between spin of the ground electric state of the nitrogen vacancy centre (NV) and other impurity spins, mainly substitutional nitrogen, NS, are observed as changes of the emission intensity as a function of external magnetic field. The features are attributed to NV-NV electron-electron spin interaction, NV- NS electron-nuclear spin interaction and NV electron spin interaction with simultaneous change of an NS electron and nuclear spin change.

  20. Local spin valve effect in lateral (Ga,MnAs/GaAs spin Esaki diode devices

    Directory of Open Access Journals (Sweden)

    M. Ciorga

    2011-06-01

    Full Text Available We report here on a local spin valve effect observed unambiguously in lateral all-semiconductor all-electrical spin injection devices, employing p+ −(Ga,MnAs/n+ −GaAs Esaki diode structures as spin aligning contacts. We discuss the observed local spin-valve signal as a result of the interplay between spin-transport-related contribution and the tunneling anisotropic magnetoresistance of the magnetic contacts. The magnitude of the spin-related magnetoresistance change is equal to 30 Ω which is twice the magnitude of the measured non-local signal.

  1. Quantitative law describing market dynamics before and after interest-rate change.

    Science.gov (United States)

    Petersen, Alexander M; Wang, Fengzhong; Havlin, Shlomo; Stanley, H Eugene

    2010-06-01

    We study the behavior of U.S. markets both before and after U.S. Federal Open Market Commission meetings and show that the announcement of a U.S. Federal Reserve rate change causes a financial shock, where the dynamics after the announcement is described by an analog of the Omori earthquake law. We quantify the rate n(t) of aftershocks following an interest-rate change at time T and find power-law decay which scales as n(t-T)∼(t-T)(-Ω) , with Ω positive. Surprisingly, we find that the same law describes the rate n'(|t-T|) of "preshocks" before the interest-rate change at time T . This study quantitatively relates the size of the market response to the news which caused the shock and uncovers the presence of quantifiable preshocks. We demonstrate that the news associated with interest-rate change is responsible for causing both the anticipation before the announcement and the surprise after the announcement. We estimate the magnitude of financial news using the relative difference between the U.S. Treasury Bill and the Federal Funds effective rate. Our results are consistent with the "sign effect," in which "bad news" has a larger impact than "good news." Furthermore, we observe significant volatility aftershocks, confirming a "market under-reaction" that lasts at least one trading day.

  2. Adaptive Rate Control Algorithm for H.264/AVC Considering Scene Change

    Directory of Open Access Journals (Sweden)

    Xiao Chen

    2013-01-01

    Full Text Available Scene change in H.264 video sequences has significant impact on the video communication quality. This paper presents a novel adaptive rate control algorithm with little additional calculation for H.264/AVC based on the scene change expression. According to the frame complexity quotiety, we define a scene change factor. It is used to allocate bits for each frame adaptively. Experimental results show that it can handle the scene change effectively. Our algorithm, in comparison to the JVT-G012 algorithm, reduces rate error and improves average peak signal-noise ratio with smaller deviation. It cannot only control bit rate accurately, but also get better video quality with the lower encoder buffer fullness to improve the quality of service.

  3. The effect of spin-orbit coupling on magnetoresistance in nonmagnetic organic semiconductors

    International Nuclear Information System (INIS)

    Zhao Jun-Qing; Ding Meng; Zhang Tian-You; Zhang Ning-Yu; Pang Yan-Tao; Ji Yan-Ju; Chen Ying; Wang Feng-Xiang; Fu Gang

    2012-01-01

    We investigated the effect of spin-orbit coupling on magnetoresistance in nonmagnetic organic semiconductors. A Lorentz-type magnetoresistance is obtained from spin-orbit coupling-dependent spin precession under the condition of a space-charge-limited current. The magnetoresistance depends on the initial spin orientation of the electron with respect to the hole in electron—hole pairs, and the increasing spin-orbit coupling slows down the change in magnetoresistance with magnetic field. The field dependence, the sign and the saturation value of the magnetoresistance are composite effects of recombination and dissociation rate constants of singlet and triplet electron—hole pairs. The simulated magnetoresistance shows good consistency with the experimental results. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

  4. Separating inverse spin Hall voltage and spin rectification voltage by inverting spin injection direction

    International Nuclear Information System (INIS)

    Zhang, Wenxu; Peng, Bin; Han, Fangbin; Wang, Qiuru; Zhang, Wanli; Soh, Wee Tee; Ong, Chong Kim

    2016-01-01

    We develop a method for universally resolving the important issue of separating the inverse spin Hall effect (ISHE) from the spin rectification effect (SRE) signal. This method is based on the consideration that the two effects depend on the spin injection direction: The ISHE is an odd function of the spin injection direction while the SRE is independent on it. Thus, the inversion of the spin injection direction changes the ISHE voltage signal, while the SRE voltage remains. It applies generally to analyzing the different voltage contributions without fitting them to special line shapes. This fast and simple method can be used in a wide frequency range and has the flexibility of sample preparation.

  5. Daily changes in temperature, not the circadian clock, regulate growth rate in Brachypodium distachyon.

    Directory of Open Access Journals (Sweden)

    Dominick A Matos

    Full Text Available Plant growth is commonly regulated by external cues such as light, temperature, water availability, and internal cues generated by the circadian clock. Changes in the rate of growth within the course of a day have been observed in the leaves, stems, and roots of numerous species. However, the relative impact of the circadian clock on the growth of grasses has not been thoroughly characterized. We examined the influence of diurnal temperature and light changes, and that of the circadian clock on leaf length growth patterns in Brachypodium distachyon using high-resolution time-lapse imaging. Pronounced changes in growth rate were observed under combined photocyles and thermocycles or with thermocycles alone. A considerably more rapid growth rate was observed at 28°C than 12°C, irrespective of the presence or absence of light. In spite of clear circadian clock regulated gene expression, plants exhibited no change in growth rate under conditions of constant light and temperature, and little or no effect under photocycles alone. Therefore, temperature appears to be the primary cue influencing observed oscillations in growth rate and not the circadian clock or photoreceptor activity. Furthermore, the size of the leaf meristem and final cell length did not change in response to changes in temperature. Therefore, the nearly five-fold difference in growth rate observed across thermocycles can be attributed to proportionate changes in the rate of cell division and expansion. A better understanding of the growth cues in B. distachyon will further our ability to model metabolism and biomass accumulation in grasses.

  6. Inhomogeneous Spin Diffusion in Traps with Cold Atoms

    DEFF Research Database (Denmark)

    Heiselberg, Henning

    2012-01-01

    The spin diusion and damped oscillations are studied in the collision of two spin polarized clouds of cold atoms with resonant interactions. The strong density dependence of the diusion coecient leads to inhomogeneous spin diusion that changes from central to surface spin ow as the temperature...

  7. Nonparametric change point estimation for survival distributions with a partially constant hazard rate.

    Science.gov (United States)

    Brazzale, Alessandra R; Küchenhoff, Helmut; Krügel, Stefanie; Schiergens, Tobias S; Trentzsch, Heiko; Hartl, Wolfgang

    2018-04-05

    We present a new method for estimating a change point in the hazard function of a survival distribution assuming a constant hazard rate after the change point and a decreasing hazard rate before the change point. Our method is based on fitting a stump regression to p values for testing hazard rates in small time intervals. We present three real data examples describing survival patterns of severely ill patients, whose excess mortality rates are known to persist far beyond hospital discharge. For designing survival studies in these patients and for the definition of hospital performance metrics (e.g. mortality), it is essential to define adequate and objective end points. The reliable estimation of a change point will help researchers to identify such end points. By precisely knowing this change point, clinicians can distinguish between the acute phase with high hazard (time elapsed after admission and before the change point was reached), and the chronic phase (time elapsed after the change point) in which hazard is fairly constant. We show in an extensive simulation study that maximum likelihood estimation is not robust in this setting, and we evaluate our new estimation strategy including bootstrap confidence intervals and finite sample bias correction.

  8. A simple method to extract information on anisotropy of particle fluxes from spin-modulated counting rates of cosmic ray telescopes

    International Nuclear Information System (INIS)

    Hsieh, K.C.; Lin, Y.C.; Sullivan, J.D.

    1975-01-01

    A simple method to extract information on anisotropy of particle fluxes from data collected by cosmic ray telescopes on spinning spacecraft but without sectored accumulators is presented. Application of this method to specific satellite data demonstrates that it requires no prior assumption on the form of angular distribution of the fluxes; furthermore, self-consistency ensures the validity of the results thus obtained. The examples show perfect agreement with the corresponding magnetic field directions

  9. In a spin at Brookhaven spin physics

    CERN Document Server

    Makdisi, Y I

    2003-01-01

    The mysterious quantity that is spin took centre stage at Brookhaven for the SPIN2002 meeting last September. The 15th biennial International Spin Physics Symposium (SPIN2002) was held at Brookhaven National Laboratory on 9-14 September 2002. Some 250 spin enthusiasts attended, including experimenters and theorists in both nuclear and high-energy physics, as well as accelerator physicists and polarized target and polarized source experts. The six-day symposium included 23 plenary talks and 150 parallel talks. SPIN2002 was preceded by a one-day spin physics tutorial for students, postdocs, and anyone else who felt the need for a refresher course. (2 refs).

  10. A feasibility study of developing toroidal tanks for a spinning spacecraft. Part 2: Evaluation of fluid behavior in spinning toroidal tanks

    Science.gov (United States)

    Anderson, J. E.

    1974-01-01

    An experimental program was conducted for the purpose of evaluating propellant behavior characteristics in spinning toroidal tanks. The effects of typical mission requirements, and related phenomena upon propellant slosh and settling, and orientation and stability of the ullage were investigated in a subscale model tank under both one-g and low-g acceleration environments. Specific conditions included were axial acceleration, spin rate, spinrate change, and spacecraft wobble, both singly and in combination. Methanol and water in combination with appropriate spin-rates and accelerations of the scale model system were used to simulate the behavior of fluorine, nitrogen tetroxide, monomethylhydrazine, and hydrazine. The experimental results indicate that no major fluid behavior problems would be encountered with the use of toroidal tanks containing any of the four propellants in a proposed spin-stabilized orbiter spacecraft.

  11. Spin-Circuit Representation of Spin Pumping

    Science.gov (United States)

    Roy, Kuntal

    2017-07-01

    Circuit theory has been tremendously successful in translating physical equations into circuit elements in an organized form for further analysis and proposing creative designs for applications. With the advent of new materials and phenomena in the field of spintronics and nanomagnetics, it is imperative to construct the spin-circuit representations for different materials and phenomena. Spin pumping is a phenomenon by which a pure spin current can be injected into the adjacent layers. If the adjacent layer is a material with a high spin-orbit coupling, a considerable amount of charge voltage can be generated via the inverse spin Hall effect allowing spin detection. Here we develop the spin-circuit representation of spin pumping. We then combine it with the spin-circuit representation for the materials having spin Hall effect to show that it reproduces the standard results as in the literature. We further show how complex multilayers can be analyzed by simply writing a netlist.

  12. Spin Coherence in Semiconductor Nanostructures

    National Research Council Canada - National Science Library

    Flatte, Michael E

    2006-01-01

    ... dots, tuning of spin coherence times for electron spin, tuning of dipolar magnetic fields for nuclear spin, spontaneous spin polarization generation and new designs for spin-based teleportation and spin transistors...

  13. Implementation of Online Promethee Method for Poor Family Change Rate Calculation

    Science.gov (United States)

    Aji, Dhady Lukito; Suryono; Widodo, Catur Edi

    2018-02-01

    This research has been done online calculation of the rate of poor family change rate by using Preference Ranking Method of Organization Of Enrichment Evaluation (PROMETHEE) .This system is very useful to monitor poverty in a region as well as for administrative services related to poverty rate. The system consists of computer clients and servers connected via the internet network. Poor family residence data obtained from the government. In addition, survey data are inputted through the client computer in each administrative village and also 23 criteria of input in accordance with the established government. The PROMETHEE method is used to evaluate the value of poverty and its weight is used to determine poverty status. PROMETHEE output can also be used to rank the poverty of the registered population of the server based on the netflow value. The poverty rate is calculated based on the current poverty rate compared to the previous poverty rate. The rate results can be viewed online and real time on the server through numbers and graphs. From the test results can be seen that the system can classify poverty status, calculate the poverty rate change rate and can determine the value and poverty ranking of each population.

  14. Comparing measurement error correction methods for rate-of-change exposure variables in survival analysis.

    Science.gov (United States)

    Veronesi, Giovanni; Ferrario, Marco M; Chambless, Lloyd E

    2013-12-01

    In this article we focus on comparing measurement error correction methods for rate-of-change exposure variables in survival analysis, when longitudinal data are observed prior to the follow-up time. Motivational examples include the analysis of the association between changes in cardiovascular risk factors and subsequent onset of coronary events. We derive a measurement error model for the rate of change, estimated through subject-specific linear regression, assuming an additive measurement error model for the time-specific measurements. The rate of change is then included as a time-invariant variable in a Cox proportional hazards model, adjusting for the first time-specific measurement (baseline) and an error-free covariate. In a simulation study, we compared bias, standard deviation and mean squared error (MSE) for the regression calibration (RC) and the simulation-extrapolation (SIMEX) estimators. Our findings indicate that when the amount of measurement error is substantial, RC should be the preferred method, since it has smaller MSE for estimating the coefficients of the rate of change and of the variable measured without error. However, when the amount of measurement error is small, the choice of the method should take into account the event rate in the population and the effect size to be estimated. An application to an observational study, as well as examples of published studies where our model could have been applied, are also provided.

  15. Interest rate changes and stock returns in Spain: A wavelet analysis

    Directory of Open Access Journals (Sweden)

    Pablo Moya-Martínez

    2015-04-01

    Full Text Available This paper investigates the relationship between changes in interest rates and the Spanish stock market at the industry level over the period from January 1993 to December 2012 using a wavelet-based approach. The empirical results indicate that Spanish industries exhibit, in general, a significant interest rate sensitivity, although the degree of interest rate exposure differs considerably across industries and depending on the time horizon under consideration. In particular, regulated industries such as Utilities, highly indebted industries such as Real Estate, Utilities or Technology and Telecommunications, and the Banking industry emerge as the most vulnerable to interest rates. Further, the link between movements in interest rates and industry equity returns is stronger at the coarsest scales. This finding is consistent with the idea that investors with long-term horizons are more likely to follow macroeconomic fundamentals, such as interest rates, in their investment decisions.

  16. Spin-lattice relaxation of individual solid-state spins

    Science.gov (United States)

    Norambuena, A.; Muñoz, E.; Dinani, H. T.; Jarmola, A.; Maletinsky, P.; Budker, D.; Maze, J. R.

    2018-03-01

    Understanding the effect of vibrations on the relaxation process of individual spins is crucial for implementing nanosystems for quantum information and quantum metrology applications. In this work, we present a theoretical microscopic model to describe the spin-lattice relaxation of individual electronic spins associated to negatively charged nitrogen-vacancy centers in diamond, although our results can be extended to other spin-boson systems. Starting from a general spin-lattice interaction Hamiltonian, we provide a detailed description and solution of the quantum master equation of an electronic spin-one system coupled to a phononic bath in thermal equilibrium. Special attention is given to the dynamics of one-phonon processes below 1 K where our results agree with recent experimental findings and analytically describe the temperature and magnetic-field scaling. At higher temperatures, linear and second-order terms in the interaction Hamiltonian are considered and the temperature scaling is discussed for acoustic and quasilocalized phonons when appropriate. Our results, in addition to confirming a T5 temperature dependence of the longitudinal relaxation rate at higher temperatures, in agreement with experimental observations, provide a theoretical background for modeling the spin-lattice relaxation at a wide range of temperatures where different temperature scalings might be expected.

  17. [Changes of historical Paragonimus metacercaria infection rates of freshwater crabs in Yongjia County].

    Science.gov (United States)

    Zhou, Teng-Jian; Chen, Hai-Qiang; Hong, Jia-Lin

    2013-12-01

    To understand the changes of Paragonimus metacercaria infection rates of freshwater crabs in Paragonimus endemic areas and explore the causes in Yongjia County, Zhejiang Province, China. A field investigation was carried out. The freshwater crabs were collected and the metacercaria were separated from the crabs. The infection rates, infectiosities and infection indexes were calculated and the results were vertically compared with the historical findings. The causes of the changes were discussed. Compared with those in 1980, the average infection rate in original endemic areas decreased from 59.71% to 21.50% (P Paragonimus metacercaria infection rate in crabs is lower than before in Yongjia County, but some super high epidemic focus of paragonimiasis still exists. Therefore, we still should strengthen the control measures.

  18. Modelling the impact of changes in the interest rates on the economy: An Austrian perspective

    Directory of Open Access Journals (Sweden)

    P Le Roux

    2004-07-01

    Full Text Available Even though econometric models and yield curve analysis are useful in assessing the impact of interest rate changes on the economic structure, their power to predict the magnitude and direction of swings in the business cycle is often restricted to the use of short-term interest rates. From an Austrian school perspective on interest rates, empirical evidence suggests that the profitability of heavy industries further downstream outperforms that of light industries in the initial stages of monetary easing, due to a rising demand for investment goods and a rise in capacity utilisation levels. This paper assesses the impact of interest rates changes on the productive structure of the economy by taking into account the effect thereof on sector earnings and ultimately share prices.

  19. Electrical Spin Injection and Threshold Reduction in a Semiconductor Laser

    Science.gov (United States)

    Holub, M.; Shin, J.; Saha, D.; Bhattacharya, P.

    2007-04-01

    A spin-polarized vertical-cavity surface-emitting laser is demonstrated with electrical spin injection from an Fe/Al0.1Ga0.9As Schottky tunnel barrier. Laser operation with a spin-polarized current results in a maximum threshold current reduction of 11% and degree of circular polarization of 23% at 50 K. A cavity spin polarization of 16.8% is estimated from spin-dependent rate equation analysis of the observed threshold reduction.

  20. High-spin nuclear spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Diamond, R.M.

    1986-07-01

    High-spin spectroscopy is the study of the changes in nuclear structure, properties, and behavior with increasing angular momentum. It involves the complex interplay between collective and single-particle motion, between shape and deformation changes, particle alignments, and changes in the pairing correlations. A review of progress in theory, experimentation, and instrumentation in this field is given. (DWL)

  1. Climate Change on Mars Inferred from Erosion Rates at the Mars Pathfinder Landing Site

    Science.gov (United States)

    Golombek, M. P.; Bridges, N. T.

    1999-01-01

    The observation that the Mars Pathfinder landing site probably looks very similar to when it was deposited by catastrophic floods some 1.8-3.5 Ga allows quantitative constraints to be placed on the rate of change at the landing site since that time. When combined with interpretations of data recently returned by the Mars Pathfinder and Global Surveyor missions and perspectives drawn from 20 years of analysis and interpretation of Viking data, these observations and inferences suggest an early warmer and wetter environment with vastly different erosion rates and a major climatic change on Mars. Additional information is contained in the original extended abstract.

  2. Paraquat prohibition and change in the suicide rate and methods in South Korea.

    Directory of Open Access Journals (Sweden)

    Woojae Myung

    Full Text Available The annual suicide rate in South Korea is the highest among the developed countries. Paraquat is a highly lethal herbicide, commonly used in South Korea as a means for suicide. We have studied the effect of the 2011 paraquat prohibition on the national suicide rate and method of suicide in South Korea. We obtained the monthly suicide rate from 2005 to 2013 in South Korea. In our analyses, we adjusted for the effects of celebrity suicides, and economic, meteorological, and seasonal factors on suicide rate. We employed change point analysis to determine the effect of paraquat prohibition on suicide rate over time, and the results were verified by structural change analysis, an alternative statistical method. After the paraquat prohibition period in South Korea, there was a significant reduction in the total suicide rate and suicide rate by poisoning with herbicides or fungicides in all age groups and in both genders. The estimated suicide rates during this period decreased by 10.0% and 46.1% for total suicides and suicides by poisoning of herbicides or fungicides, respectively. In addition, method substitution effect of paraquat prohibition was found in suicide by poisoning by carbon monoxide, which did not exceed the reduction in the suicide rate of poisoning with herbicides or fungicides. In South Korea, paraquat prohibition led to a lower rate of suicide by paraquat poisoning, as well as a reduction in the overall suicide rate. Paraquat prohibition should be considered as a national suicide prevention strategy in developing and developed countries alongside careful observation for method substitution effects.

  3. Paraquat prohibition and change in the suicide rate and methods in South Korea.

    Science.gov (United States)

    Myung, Woojae; Lee, Geung-Hee; Won, Hong-Hee; Fava, Maurizio; Mischoulon, David; Nyer, Maren; Kim, Doh Kwan; Heo, Jung-Yoon; Jeon, Hong Jin

    2015-01-01

    The annual suicide rate in South Korea is the highest among the developed countries. Paraquat is a highly lethal herbicide, commonly used in South Korea as a means for suicide. We have studied the effect of the 2011 paraquat prohibition on the national suicide rate and method of suicide in South Korea. We obtained the monthly suicide rate from 2005 to 2013 in South Korea. In our analyses, we adjusted for the effects of celebrity suicides, and economic, meteorological, and seasonal factors on suicide rate. We employed change point analysis to determine the effect of paraquat prohibition on suicide rate over time, and the results were verified by structural change analysis, an alternative statistical method. After the paraquat prohibition period in South Korea, there was a significant reduction in the total suicide rate and suicide rate by poisoning with herbicides or fungicides in all age groups and in both genders. The estimated suicide rates during this period decreased by 10.0% and 46.1% for total suicides and suicides by poisoning of herbicides or fungicides, respectively. In addition, method substitution effect of paraquat prohibition was found in suicide by poisoning by carbon monoxide, which did not exceed the reduction in the suicide rate of poisoning with herbicides or fungicides. In South Korea, paraquat prohibition led to a lower rate of suicide by paraquat poisoning, as well as a reduction in the overall suicide rate. Paraquat prohibition should be considered as a national suicide prevention strategy in developing and developed countries alongside careful observation for method substitution effects.

  4. Muon spin rotation in solids

    Science.gov (United States)

    Stronach, C. E.

    1983-01-01

    The muon spin rotation (MuSR) technique is used to probe the microscopic electron density in materials. High temperature MuSR and magnetization measurements in nickel are in progress to allow an unambiguous determination of the muon impurity interaction and the impurity induced change in local spin density. The first results on uniaxial stress induced frequency shifts in an Fe single crystal are also reported.

  5. Targeting deforestation rates in climate change policy: a "Preservation Pathway" approach

    OpenAIRE

    Gurney, Kevin R; Raymond, Leigh

    2008-01-01

    Abstract We present a new methodological approach to incorporating deforestation within the international climate change negotiating regime. The approach, called "Preservation Pathway" combines the desire for forest preservation with the need to reduce emissions associated with forest loss by focusing on the relative rate of change of forest cover as the criteria by which countries gain access to trading preserved forest carbon stocks. This approach avoids the technically challenging task of ...

  6. Increasing infection rate in multiple implanted pulse generator changes in movement disorder patients treated with deep brain stimulation

    DEFF Research Database (Denmark)

    Thrane, Jens F; Sunde, Niels A; Bergholt, Bo

    2014-01-01

    Increasing infection rate in multiple implanted pulse generator changes in movement disorder patients treated with deep brain stimulation......Increasing infection rate in multiple implanted pulse generator changes in movement disorder patients treated with deep brain stimulation...

  7. Key landscape ecology metrics for assessing climate change adaptation options: Rate of change and patchiness of impacts

    Science.gov (United States)

    López-Hoffman, Laura; Breshears, David D.; Allen, Craig D.; Miller, Marc L.

    2013-01-01

    Under a changing climate, devising strategies to help stakeholders adapt to alterations to ecosystems and their services is of utmost importance. In western North America, diminished snowpack and river flows are causing relatively gradual, homogeneous (system-wide) changes in ecosystems and services. In addition, increased climate variability is also accelerating the incidence of abrupt and patchy disturbances such as fires, floods and droughts. This paper posits that two key variables often considered in landscape ecology—the rate of change and the degree of patchiness of change—can aid in developing climate change adaptation strategies. We use two examples from the “borderland” region of the southwestern United States and northwestern Mexico. In piñon-juniper woodland die-offs that occurred in the southwestern United States during the 2000s, ecosystem services suddenly crashed in some parts of the system while remaining unaffected in other locations. The precise timing and location of die-offs was uncertain. On the other hand, slower, homogeneous change, such as the expected declines in water supply to the Colorado River delta, will likely impact the entire ecosystem, with ecosystem services everywhere in the delta subject to alteration, and all users likely exposed. The rapidity and spatial heterogeneity of faster, patchy climate change exemplified by tree die-off suggests that decision-makers and local stakeholders would be wise to operate under a Rawlsian “veil of ignorance,” and implement adaptation strategies that allow ecosystem service users to equitably share the risk of sudden loss of ecosystem services before actual ecosystem changes occur. On the other hand, in the case of slower, homogeneous, system-wide impacts to ecosystem services as exemplified by the Colorado River delta, adaptation strategies can be implemented after the changes begin, but will require a fundamental rethinking of how ecosystems and services are used and valued. In

  8. Economic growth and suicide rate changes: a case in China from 1982 to 2005.

    Science.gov (United States)

    Zhang, J; Ma, J; Jia, C; Sun, J; Guo, X; Xu, A; Li, W

    2010-04-01

    It is to estimate the trend of suicide rate changes during the past three decades in China and try to identify its social and economic correlates. Official data of suicide rates and economic indexes during 1982-2005 from Shandong Province of China were analyzed. The suicide data were categorized for the rural / urban location and gender, and the economic indexes include GDP, GDP per capita, rural income, and urban income, all adjusted for inflation. We found a significant increase of economic development and decrease of suicide rates over the past decades under study. The suicide rate decrease is correlated with the tremendous growth of economy. The unusual decrease of Chinese suicide rates in the past decades is accounted for within the Chinese cultural contexts and maybe by the Strain Theory of Suicide. Copyright (c) 2009 Elsevier Masson SAS. All rights reserved.

  9. Investigating the asymmetric relationship between inflation-output growth exchange rate changes

    Science.gov (United States)

    Chu, Jenq Fei; Sek, Siok Kun

    2017-08-01

    The relationship between inflation-output growth or output variation has long been studied. In this study, we extend the investigation under two exchange rate flexibility/regime in four Asian countries (Indonesia, Korea, Philippines and Thailand) that have experienced drastic exchange rate regime changes aftermath the financial crisis of 1997. These countries have switched from fixed/rigid exchange rate regime to flexible exchange rate and inflation targeting (IT) regime after the crisis. Our main objective is to compare the inflation-output trade-off relationship in the pre-IT and post-IT periods as a tool to evaluate the efficiency of monetary policy. A nonlinear autoregressive distributed lags (NARDL) model is applied to capture the asymmetric effects of exchange rate changes (increases and decreases). The data ranging from 1981M1 onwards till 2016M3. Our results show that exchange rate has asymmetric effect on inflation both short-run and long-run with larger impact in the post-IT period under flexible regime. Depreciation of exchange rate has leads to higher inflation. Furthermore, we find evidences on the relationship between inflation and growth in both short-run and long-run, but the trade-off only detected in the short run both in the pre- and post-IT periods.

  10. Changes in Heart Rate Variability after Coronary Artery Bypass Grafting and Clinical Importance of These Findings.

    Science.gov (United States)

    Lakusic, Nenad; Mahovic, Darija; Kruzliak, Peter; Cerkez Habek, Jasna; Novak, Miroslav; Cerovec, Dusko

    2015-01-01

    Heart rate variability is a physiological feature indicating the influence of the autonomic nervous system on the heart rate. Association of the reduced heart rate variability due to myocardial infarction and the increased postinfarction mortality was first described more than thirty years ago. Many studies have unequivocally demonstrated that coronary artery bypass grafting surgery generally leads to significant reduction in heart rate variability, which is even more pronounced than after myocardial infarction. Pathophysiologically, however, the mechanisms of heart rate variability reduction associated with acute myocardial infarction and coronary artery bypass grafting are different. Generally, heart rate variability gradually recovers to the preoperative values within six months of the procedure. Unlike the reduced heart rate variability in patients having sustained myocardial infarction, a finding of reduced heart rate variability after coronary artery bypass surgery is not considered relevant in predicting mortality. Current knowledge about changes in heart rate variability in coronary patients and clinical relevance of such a finding in patients undergoing coronary artery bypass grafting are presented.

  11. Genomics of Adaptation Depends on the Rate of Environmental Change in Experimental Yeast Populations.

    Science.gov (United States)

    Gorter, Florien A; Derks, Martijn F L; van den Heuvel, Joost; Aarts, Mark G M; Zwaan, Bas J; de Ridder, Dick; de Visser, J Arjan G M

    2017-10-01

    The rate of directional environmental change may have profound consequences for evolutionary dynamics and outcomes. Yet, most evolution experiments impose a sudden large change in the environment, after which the environment is kept constant. We previously cultured replicate Saccharomyces cerevisiae populations for 500 generations in the presence of either gradually increasing or constant high concentrations of the heavy metals cadmium, nickel, and zinc. Here, we investigate how each of these treatments affected genomic evolution. Whole-genome sequencing of evolved clones revealed that adaptation occurred via a combination of SNPs, small indels, and whole-genome duplications and other large-scale structural changes. In contrast to some theoretical predictions, gradual and abrupt environmental change caused similar numbers of genomic changes. For cadmium, which is toxic already at comparatively low concentrations, mutations in the same genes were used for adaptation to both gradual and abrupt increase in concentration. Conversely, for nickel and zinc, which are toxic at high concentrations only, mutations in different genes were used for adaptation depending on the rate of change. Moreover, evolution was more repeatable following a sudden change in the environment, particularly for nickel and zinc. Our results show that the rate of environmental change and the nature of the selection pressure are important drivers of evolutionary dynamics and outcomes, which has implications for a better understanding of societal problems such as climate change and pollution. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  12. The kinematic differences between off-spin and leg-spin bowling in cricket.

    Science.gov (United States)

    Beach, Aaron J; Ferdinands, René E D; Sinclair, Peter J

    2016-09-01

    Spin bowling is generally coached using a standard technical framework, but this practice has not been based upon a comparative biomechanical analysis of leg-spin and off-spin bowling. This study analysed the three-dimensional (3D) kinematics of 23 off-spin and 20 leg-spin bowlers using a Cortex motion analysis system to identify how aspects of the respective techniques differed. A multivariate ANOVA found that certain data tended to validate some of the stated differences in the coaching literature. Off-spin bowlers had a significantly shorter stride length (p = 0.006) and spin rate (p = 0.001), but a greater release height than leg-spinners (p = 0.007). In addition, a number of other kinematic differences were identified that were not previously documented in coaching literature. These included a larger rear knee flexion (p = 0.007), faster approach speed (p < 0.001), and flexing elbow action during the arm acceleration compared with an extension action used by most of the off-spin bowlers. Off-spin and leg-spin bowlers also deviated from the standard coaching model for the shoulder alignment, front knee angle at release, and forearm mechanics. This study suggests that off-spin and leg-spin are distinct bowling techniques, supporting the development of two different coaching models in spin bowling.

  13. Thermal imaging of spin Peltier effect

    Science.gov (United States)

    Daimon, Shunsuke; Iguchi, Ryo; Hioki, Tomosato; Saitoh, Eiji; Uchida, Ken-Ichi

    2016-12-01

    The Peltier effect modulates the temperature of a junction comprising two different conductors in response to charge currents across the junction, which is used in solid-state heat pumps and temperature controllers in electronics. Recently, in spintronics, a spin counterpart of the Peltier effect was observed. The `spin Peltier effect' modulates the temperature of a magnetic junction in response to spin currents. Here we report thermal imaging of the spin Peltier effect; using active thermography technique, we visualize the temperature modulation induced by spin currents injected into a magnetic insulator from an adjacent metal. The thermal images reveal characteristic distribution of spin-current-induced heat sources, resulting in the temperature change confined only in the vicinity of the metal/insulator interface. This finding allows us to estimate the actual magnitude of the temperature modulation induced by the spin Peltier effect, which is more than one order of magnitude greater than previously believed.

  14. Predicting changes in reported notifiable disease rates for New Zealand using a SIR modelling approach

    Science.gov (United States)

    McBride, Graham; Slaney, David; Tait, Andrew

    2013-04-01

    The New Zealand health system has defined as 'notifiable' over 50 diseases. Of these campylobacteriosis is the most commonly reported comprising 41% of all notifications in 2011 (presently about 150 illness cases per 100,000 population per annum). Furthermore, the incidence of this mild illness, which is potentially waterborne, is under-reported by at least an order-of-magnitude. Increased downstream pathogen loads and/or disease incidence have been found to be associated with increased rainfall, particularly in agricultural landscapes. Therefore, given the predominance of agricultural land uses in New Zealand, transmission and exposure to its agent (thermotolerant Campylobacter bacteria) may be affected by changing rainfall and temperature patterns associated with climate change. Reporting rates for other potentially water-borne zoonoses are also noticeable (for example, the reported rate for cryptosporidiosis for 2011 was 14 per 100,000 population). The distribution of Cryptosporidium oocysts in the environment may be influenced by climate change because it has often been implicated in drinking-water contamination, and heavy rainfall events have been found to be associated with increased pathogen loads in rivers and disease incidence. Given this background, which may also be applicable to other countries with agriculturally-dominated landscapes, a New Zealand study was initiated to develop a decision-support system for the projected effects of climate change on a selected suite of environmentally-transmitted pathogens, including Campylobacter and Cryptosporodium oocysts. Herein we report on the manner in which a linear SIR (Susceptible-Ill-Recovered) model previously developed for campylobacteriosis can be extended to cryptosporidiosis, applied to changes in pathogen contact rate and hence reported illness, and coupled to climate change projections associated with different greenhouse gas emission scenarios. The resulting SIR model outputs provided projected

  15. Spin-bowling in cricket re-visited: model trajectories for various spin-vector angles

    Science.gov (United States)

    Robinson, Garry; Robinson, Ian

    2016-08-01

    In this paper we investigate, via the calculation of model trajectories appropriate to slow bowling in cricket, the effects on the flight path of the ball before pitching due to changes in the angle of the spin-vector. This was accomplished by allowing the spin-vector to vary in three ways. Firstly, from off-spin, where the spin-vector points horizontally and directly down the pitch, to top-spin where it points horizontally towards the off-side of the pitch. Secondly, from off-spin to side-spin where, for side-spin, the spin-vector points vertically upwards. Thirdly, where the spin-vector points horizontally and at 45° to the pitch (in the general direction of ‘point’, as viewed by the bowler), and is varied towards the vertical, while maintaining the 45° angle in the horizontal plane. It is found that, as is well known, top-spin causes the ball to dip in flight, side-spin causes the ball to move side-ways in flight and, perhaps most importantly, off-spin can cause the ball to drift to the off-side of the pitch late in its flight as it begins to fall. At a more subtle level it is found that, if the total spin is kept constant and a small amount of top-spin is added to the ball at the expense of some off-spin, there is little change in the side-ways drift. However, a considerable reduction in the length at which the ball pitches occurs, ˜25 cm, an amount that batsmen can ignore at their peril. On the other hand, a small amount of side-spin introduced to a top-spin delivery does not alter the point of pitching significantly, but produces a considerable amount of side-ways drift, ˜10 cm or more. For pure side-spin the side-ways drift is up to ˜30 cm. When a side-spin component is added to the spin of a ball bowled with a mixture of off-spin and top-spin in equal proportions, significant movement occurs in both the side-ways direction and in the point of pitching, of the order of a few tens of centimetres.

  16. A systematic review on heart-rate recovery to monitor changes in training status in athletes

    NARCIS (Netherlands)

    Daanen, H.A.M.; Lamberts, R.P.; Kallen, V.L.; Jin, A.; Van Meeteren, N.L.U.

    2012-01-01

    Heart-rate recovery (HRR) has been proposed as a marker of autonomic function and training status in athletes. The authors performed a systematic review of studies that examined HRR after training. Five cross-sectional studies and 8 studies investigating changes over time (longitudinal) met our

  17. Intelligence and Changes in Regional Cerebral Glucose Metabolic Rate Following Learning.

    Science.gov (United States)

    Haier, Richard J.; And Others

    1992-01-01

    A study of eight normal right-handed men demonstrates widespread significant decreases in brain glucose metabolic rate (GMR) following learning a complex computer task, a computer game. Correlations between magnitude of GMR change and intelligence scores are also demonstrated. (SLD)

  18. Optimal technology adoption when the arrival rate of new technologies changes

    NARCIS (Netherlands)

    Hagspiel, V.; Huisman, K.J.M.; Nunes, Claudia

    2015-01-01

    Our paper contributes to the literature of technology adoption. In most of these models it is assumed that the intensity rate of new arrivals is constant. We extend this approach by assuming that after the last technology jump the intensity of a new arrival can change. Right after the arrival of a

  19. Community Colleges and Labor Market Conditions: How Does Enrollment Demand Change Relative to Local Unemployment Rates?

    Science.gov (United States)

    Hillman, Nicholas W.; Orians, Erica Lee

    2013-01-01

    This study uses fixed-effects panel data techniques to estimate the elasticity of community college enrollment demand relative to local unemployment rates. The findings suggest that community college enrollment demand is counter-cyclical to changes in the labor market, as enrollments rise during periods of weak economic conditions. Using national…

  20. Effect of Conceptual Change Approach on Students' Understanding of Reaction Rate Concepts

    Science.gov (United States)

    Kingir, Sevgi; Geban, Omer

    2012-01-01

    The purpose of the present study was to investigate the effect of conceptual change text oriented instruction compared to traditional instruction on 10th grade students' understanding of reaction rate concepts. 45 students from two classes of the same teacher in a public high school participated in this study. Students in the experimental group…

  1. The Effect of Conceptual Change Pedagogy on Students' Conceptions of Rate of Reaction

    Science.gov (United States)

    Calik, Muammer; Kolomuc, Ali; Karagolge, Zafer

    2010-01-01

    This paper reports on an investigation of the effect of conceptual change pedagogy on students' conceptions of "rate of reaction" concepts. The study used a pre-test/post-test non-equivalent comparison group design approach and the sample consisted of 72 Turkish grade-11 students (aged 16-18 years) selected from two intact classrooms.…

  2. 7 CFR 1779.80 - Interest rate changes after loan closing.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 12 2010-01-01 2010-01-01 false Interest rate changes after loan closing. 1779.80 Section 1779.80 Agriculture Regulations of the Department of Agriculture (Continued) RURAL UTILITIES SERVICE, DEPARTMENT OF AGRICULTURE (CONTINUED) WATER AND WASTE DISPOSAL PROGRAMS GUARANTEED LOANS § 1779...

  3. THE EFFECT OF OPENING WINDOWS ON AIR CHANGE RATES IN TWO HOMES

    Science.gov (United States)

    Over 300 air change rate experiments were completed in two occupied residences: a two-story detached house in Redwood City, CA and a three-story townhouse in Reston, VA. A continuous monitor was used to measure the decay of sulfur hexafluoride tracer gas over periods of 1 to 1...

  4. 76 FR 65639 - International Mail: Proposed Product Rate and Fee Changes

    Science.gov (United States)

    2011-10-24

    ... Customs Clearance and Delivery Fee International Reply Coupons International Business Reply Service The... * * * * * International Business Reply Service (382) [For each country that offers International Business Reply Service... POSTAL SERVICE 39 CFR Part 20 International Mail: Proposed Product Rate and Fee Changes AGENCY...

  5. Effect of transient change in strain rate on plastic flow behaviour of ...

    Indian Academy of Sciences (India)

    Steels; stress–strain measurement; plastic flow; mechanical properties; metallurgy. ... Haasen plot revealed that the mobile dislocation density remained almost invariant at the juncture where there was a sudden increase in stress with a change in strain rate and the plastic flow was solely dependent on the velocity of mobile ...

  6. Changes in heart rate variability and QT variability during the first trimester of pregnancy.

    Science.gov (United States)

    Carpenter, R E; D'Silva, L A; Emery, S J; Uzun, O; Rassi, D; Lewis, M J

    2015-03-01

    The risk of new-onset arrhythmia during pregnancy is high, presumably relating to changes in both haemodynamic and cardiac autonomic function. The ability to non-invasively assess an individual's risk of developing arrhythmia during pregnancy would therefore be clinically significant. We aimed to quantify electrocardiographic temporal characteristics during the first trimester of pregnancy and to compare these with non-pregnant controls. Ninety-nine pregnant women and sixty-three non-pregnant women underwent non-invasive cardiovascular and haemodynamic assessment during a protocol consisting of various physiological states (postural manoeurvres, light exercise and metronomic breathing). Variables measured included stroke volume, cardiac output, heart rate, heart rate variability, QT and QT variability and QTVI (a measure of the variability of QT relative to that of RR). Heart rate (p pregnancy only during the supine position (p pregnancy in all physiological states (p pregnancy in all states (p pregnancy is associated with substantial changes in heart rate variability, reflecting a reduction in parasympathetic tone and an increase in sympathetic activity. QTVI shifted to a less favourable value, reflecting a greater than normal amount of QT variability. QTVI appears to be a useful method for quantifying changes in QT variability relative to RR (or heart rate) variability, being sensitive not only to physiological state but also to gestational age. We support the use of non-invasive markers of cardiac electrical variability to evaluate the risk of arrhythmic events in pregnancy, and we recommend the use of multiple physiological states during the assessment protocol.

  7. Heat shock response in yeast involves changes in both transcription rates and mRNA stabilities.

    Directory of Open Access Journals (Sweden)

    Laia Castells-Roca

    Full Text Available We have analyzed the heat stress response in the yeast Saccharomyces cerevisiae by determining mRNA levels and transcription rates for the whole transcriptome after a shift from 25 °C to 37 °C. Using an established mathematical algorithm, theoretical mRNA decay rates have also been calculated from the experimental data. We have verified the mathematical predictions for selected genes by determining their mRNA decay rates at different times during heat stress response using the regulatable tetO promoter. This study indicates that the yeast response to heat shock is not only due to changes in transcription rates, but also to changes in the mRNA stabilities. mRNA stability is affected in 62% of the yeast genes and it is particularly important in shaping the mRNA profile of the genes belonging to the environmental stress response. In most cases, changes in transcription rates and mRNA stabilities are homodirectional for both parameters, although some interesting cases of antagonist behavior are found. The statistical analysis of gene targets and sequence motifs within the clusters of genes with similar behaviors shows that both transcriptional and post-transcriptional regulons apparently contribute to the general heat stress response by means of transcriptional factors and RNA binding proteins.

  8. Climate Change and Elevated Extinction Rates of Reptiles from Mediterranean Islands

    Science.gov (United States)

    Foufopoulos, Johannes; Kilpatrick, A. Marm; Ives, Anthony R.

    2011-01-01

    Recent climate change has caused the distributions of many species to shift poleward, yet few empirical studies have addressed which species will likely be vulnerable to longer-term climate changes. To investigate past consequences of climate change, we calculated the population extinction rates of 35 reptile species from 87 Greek land-bridge islands in the Mediterranean that occurred over the last 16,000 years. Population extinction rates were higher for those species that today have more northern distributions. We further found that northern species requiring cool, mesic habitats had less available suitable habitat among islands, implicating loss of suitable habitat in their elevated extinction rates. These extinctions occurred in the context of increasing fragmentation, with islands shrinking and separating as sea levels rose. Thus, the circumstances faced by reptiles on the islands are similar to challenges for numerous species today that must cope with a changing climate while living in an increasingly human-fragmented landscape. Our island-biogeographical approach to investigating historical population extinctions gives insight into the long-term patterns of species responses to climate changes. PMID:21091198

  9. Flexibility in metabolic rate confers a growth advantage under changing food availability

    Science.gov (United States)

    Auer, Sonya K; Salin, Karine; Rudolf, Agata M; Anderson, Graeme J; Metcalfe, Neil B; Ardia, Daniel

    2015-01-01

    Phenotypic flexibility in physiological, morphological and behavioural traits can allow organisms to cope with environmental challenges. Given recent climate change and the degree of habitat modification currently experienced by many organisms, it is therefore critical to quantify the degree of phenotypic variation present within populations, individual capacities to change and what their consequences are for fitness. Flexibility in standard metabolic rate (SMR) may be particularly important since SMR reflects the minimal energetic cost of living and is one of the primary traits underlying organismal performance. SMR can increase or decrease in response to food availability, but the consequences of these changes for growth rates and other fitness components are not well known. We examined individual variation in metabolic flexibility in response to changing food levels and its consequences for somatic growth in juvenile brown trout (Salmo trutta). SMR increased when individuals were switched to a high food ration and decreased when they were switched to a low food regime. These shifts in SMR, in turn, were linked with individual differences in somatic growth; those individuals that increased their SMR more in response to elevated food levels grew fastest, while growth at the low food level was fastest in those individuals that depressed their SMR most. Flexibility in energy metabolism is therefore a key mechanism to maximize growth rates under the challenges imposed by variability in food availability and is likely to be an important determinant of species’ resilience in the face of global change. PMID:25939669

  10. Decomposing change in China's suicide rate, 1990-2010: ageing and urbanisation.

    Science.gov (United States)

    Sha, Feng; Yip, Paul S F; Law, Yik Wa

    2017-02-01

    The study empirically quantifies the contributions of age composition and urbanisation to changes in the suicide rate in China over the periods 1990-2000 and 2000-2010. A decompositional method was used to quantify the absolute and relative contributions of the age structure; the age-specific proportion of the urban population and the suicide rate of each age-specific, gender-specific and urban/rural cohort to the overall suicide rates in the two 10-year intervals. In the period between 1990 and 2000, a significant decline in the suicide rate among younger age groups (especially young rural women) was identified as the main driving force of the downward trend in the overall suicide rate. In 2000-2010, the rate of decline in suicide was predominantly explained by the drop in the suicide rate among all age groups in rural areas, with the exception of those aged over 80. The positive impact of urbanisation on the decline of the suicide rate has gradually diminished relative to the earlier period. As the positive impact of urbanisation on suicide rates is diminishing, further urbanisation and rapid change in society may induce stress and adjustment problems that are not conducive to the promotion of well-being. Furthermore, as China is facing the prospects of slower economic growth and a rapidly ageing population, suicides among older adults may also be elevated, particularly among those in rural areas with insufficient healthcare and social support. In order to maintain the decreasing trend of suicide in China, it is important for the Chinese government to pay more attention to the mental well-being of the population and to mitigate the stress of urban life and to provide timely support to older adults especially in rural areas. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  11. Changes in Consumer Demand Following Public Reporting of Summary Quality Ratings: An Evaluation in Nursing Homes.

    Science.gov (United States)

    Werner, Rachel M; Konetzka, R Tamara; Polsky, Daniel

    2016-06-01

    Limited consumer use of health care report cards may be due to the large amount of information presented in report cards, which can be difficult to understand. These limitations may be overcome with summary measures. Our objective was to evaluate consumer response to summary measures in the setting of nursing homes. 2005-2010 nursing home Minimum Data Set and Online Survey, Certification and Reporting (OSCAR) datasets. In December 2008, Medicare converted its nursing home report card to summary or star ratings. We test whether there was a change in consumer demand for nursing homes related to the nursing home's star rating after the information was released. The star rating system was associated with a significant change in consumer demand for low- and high-scoring facilities. After the star-based rating system was released, 1-star facilities typically lost 8 percent of their market share and 5-star facilities gained over 6 percent of their market share. The nursing home star rating system significantly affected consumer demand for high- and low-rated nursing homes. These results support the use of summary measures in report cards. © Health Research and Educational Trust.

  12. Air change rates of motor vehicles and in-vehicle pollutant concentrations from secondhand smoke.

    Science.gov (United States)

    Ott, Wayne; Klepeis, Neil; Switzer, Paul

    2008-05-01

    The air change rates of motor vehicles are relevant to the sheltering effect from air pollutants entering from outside a vehicle and also to the interior concentrations from any sources inside its passenger compartment. We made more than 100 air change rate measurements on four motor vehicles under moving and stationary conditions; we also measured the carbon monoxide (CO) and fine particle (PM(2.5)) decay rates from 14 cigarettes smoked inside the vehicle. With the vehicle stationary and the fan off, the ventilation rate in air changes per hour (ACH) was less than 1 h(-1) with the windows closed and increased to 6.5 h(-1) with one window fully opened. The vehicle speed, window position, ventilation system, and air conditioner setting was found to affect the ACH. For closed windows and passive ventilation (fan off and no recirculation), the ACH was linearly related to the vehicle speed over the range from 15 to 72 mph (25 to 116 km h(-1)). With a vehicle moving, windows closed, and the ventilation system off (or the air conditioner set to AC Max), the ACH was less than 6.6 h(-1) for speeds ranging from 20 to 72 mph (32 to 116 km h(-1)). Opening a single window by 3'' (7.6 cm) increased the ACH by 8-16 times. For the 14 cigarettes smoked in vehicles, the deposition rate k and the air change rate a were correlated, following the equation k=1.3a (R(2)=82%; n=14). With recirculation on (or AC Max) and closed windows, the interior PM(2.5) concentration exceeded 2000 microg m(-3) momentarily for all cigarettes tested, regardless of speed. The concentration time series measured inside the vehicle followed the mathematical solutions of the indoor mass balance model, and the 24-h average personal exposure to PM(2.5) could exceed 35 microg m(-3) for just two cigarettes smoked inside the vehicle.

  13. Spin trapping in γ-irradiated system

    International Nuclear Information System (INIS)

    Taniguchi, Hitoshi

    1998-01-01

    Spin trapping techniques, allowing one to visualize transient free radical populations by reacting short-lived radicals with a spin trap to produce persistent spin adduct radicals, require that the rate constant for parent radical addition to the spin trap be sufficiently large. The study on the rate of spin trapping reactions, dependent upon steric and electronic (polar) interactions in the complex, has been extended to nitrone spin trapping using 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) as a spin trap. We concentrated on the trapping of carboxyalkyl radicals which feature strong hydrogen bonding between the hydroxyl group of the spin addend carboxyl function and the aminosyl oxygen, and a strongly electron withdrawing effect of the spin addend on the DMPO ring. These two features in these radicals, enhancing the polarization of the N 1 -C 2 bond to produce spin adduct fragmentation, were found to be significantly more pronounced than in the case of hydroxylalkyl radical adducts to DMPO. (J.P.N.)

  14. Spin Structure Analyses of Antiferromagnets

    International Nuclear Information System (INIS)

    Chung, Jae Ho; Song, Young Sang; Lee, Hak Bong

    2010-05-01

    We have synthesized series of powder sample of incommensurate antiferromagnetic multiferroics, (Mn, Co)WO 4 and Al doped Ba 0.5 Sr 1.5 Zn 2 Fe 12 O 22 , incommensurate antiferromagnetic multiferroics. Their spin structure was studied by using the HRPD. In addition, we have synthesized series of crystalline samples of incommensurate multiferroics, (Mn, Co)WO 4 and olivines. Their spin structure was investigated using neutron diffraction under high magnetic field. As a result, we were able to draw the phase diagram of (Mn, Co)WO 4 as a function of composition and temperature. We learned the how the spin structure changes with increased ionic substitution. Finally we have drawn the phase diagram of the multicritical olivine Mn2SiS4/Mn2GeS4 as a function of filed and temperature through the spin structure studies

  15. Unprecedented rates of land-use transformation in modeled climate change mitigation pathways

    Science.gov (United States)

    Turner, P. A.; Field, C. B.; Lobell, D. B.; Sanchez, D.; Mach, K. J.

    2017-12-01

    Integrated assessment models (IAMs) generate climate change mitigation scenarios consistent with global temperature targets. To limit warming to 2°, stylized cost-effective mitigation pathways rely on extensive deployments of carbon dioxide (CO2) removal (CDR) technologies, including multi-gigatonne yearly carbon removal from the atmosphere through bioenergy with carbon capture and storage (BECCS) and afforestation/reforestation. These assumed CDR deployments keep ambitious temperature limits in reach, but associated rates of land-use transformation have not been evaluated. For IAM scenarios from the IPCC Fifth Assessment Report, we compare rates of modeled land-use conversion to recent observed commodity crop expansions. In scenarios with a likely chance of limiting warming to 2° in 2100, the rate of energy cropland expansion supporting BECCS exceeds past commodity crop rates by several fold. In some cases, mitigation scenarios include abrupt reversal of deforestation, paired with massive afforestation/reforestation. Specifically, energy cropland in solution to the climate challenge.

  16. Spin Transport Measurements in Hydrogenated Graphene Devices

    Science.gov (United States)

    Koon, Gavin; Balakrishnan, Jayakumar; Oezyilmaz, Barbaros

    2013-03-01

    Graphene with all its extraordinary properties still fall short when it comes to manipulation of electron spins. Chemically modified Graphene has been explored by many to further enhance Graphene properties, tailoring it to suit desired application purposes. Here we study the effects of hydrogenation rate on graphene spin transport, spin relaxation time and length in this defected system. These findings are important for future theoretical and experimental studies on other adatoms modified Graphene.

  17. Coordinated Changes in Mutation and Growth Rates Induced by Genome Reduction

    Directory of Open Access Journals (Sweden)

    Issei Nishimura

    2017-07-01

    Full Text Available Genome size is determined during evolution, but it can also be altered by genetic engineering in laboratories. The systematic characterization of reduced genomes provides valuable insights into the cellular properties that are quantitatively described by the global parameters related to the dynamics of growth and mutation. In the present study, we analyzed a small collection of W3110 Escherichia coli derivatives containing either the wild-type genome or reduced genomes of various lengths to examine whether the mutation rate, a global parameter representing genomic plasticity, was affected by genome reduction. We found that the mutation rates of these cells increased with genome reduction. The correlation between genome length and mutation rate, which has been reported for the evolution of bacteria, was also identified, intriguingly, for genome reduction. Gene function enrichment analysis indicated that the deletion of many of the genes encoding membrane and transport proteins play a role in the mutation rate changes mediated by genome reduction. Furthermore, the increase in the mutation rate with genome reduction was highly associated with a decrease in the growth rate in a nutrition-dependent manner; thus, poorer media showed a larger change that was of higher significance. This negative correlation was strongly supported by experimental evidence that the serial transfer of the reduced genome improved the growth rate and reduced the mutation rate to a large extent. Taken together, the global parameters corresponding to the genome, growth, and mutation showed a coordinated relationship, which might be an essential working principle for balancing the cellular dynamics appropriate to the environment.

  18. Nuclear spin pumping and electron spin susceptibilities

    NARCIS (Netherlands)

    Danon, J.; Nazarov, Y.V.

    2011-01-01

    In this work we present a new formalism to evaluate the nuclear spin dynamics driven by hyperfine interaction with nonequilibrium electron spins. To describe the dynamics up to second order in the hyperfine coupling it suffices to evaluate the susceptibility and fluctuations of the electron spin.

  19. Determining the predictors of change in quality of life self-ratings and carer-ratings for community-dwelling people with Alzheimer disease.

    Science.gov (United States)

    Bosboom, Pascalle R; Alfonso, Helman; Almeida, Osvaldo P

    2013-01-01

    The aim of this study was to determine the factors that mediate changes in Health Related Quality of Life (HRQoL) ratings by community-dwelling people with Alzheimer disease (AD) and carers over a period of 18 months. We completed an 18-month longitudinal study of 80 community-dwelling older adults diagnosed with probable AD of mild or moderate severity (NINCDS-ADRD criteria) and their family carers. The primary outcome of interest was the 18-month change in HRQoL ratings as measured with the Quality of Life-AD (QoL-AD) (by carer and by self). Explanatory variables included demographics, lifestyle, cognition, awareness, psychopathology, burden-of-care, use of medication, and functionality in daily life. We found a significant decline (8.7%, P=0.003) in QoL-AD carer-ratings, but not in self-ratings. The final parsimonious model of predictors of changes in QoL-AD self-ratings explained 22.6% of the variance; only changes on Hospital Anxiety and Depression Scale Anxiety retained significance. The final model of predictors of changes in carer-ratings explained 55.0% of the variance: that is, changes on Informant Questionnaire on Cognitive Decline in the Elderly, changes on Hospital Anxiety and Depression Scale Depression, practicing hobbies at 18 months, and number of visit(s) or admission(s) to hospital. HRQoL self-ratings and carer-ratings of community-dwelling people with AD do not decline at same rate over 18 months and changes are associated with different factors. Interventions designed to optimize quality of life of people with AD should consider carefully whose HRQoL ratings they wish to change.

  20. Individuals exhibit consistent differences in their metabolic rates across changing thermal conditions.

    Science.gov (United States)

    Auer, Sonya K; Salin, Karine; Anderson, Graeme J; Metcalfe, Neil B

    2018-03-01

    Metabolic rate has been linked to growth, reproduction, and survival at the individual level and is thought to have far reaching consequences for the ecology and evolution of organisms. However, metabolic rates must be consistent (i.e. repeatable) over at least some portion of the lifetime in order to predict their longer-term effects on population dynamics and how they will respond to selection. Previous studies demonstrate that metabolic rates are repeatable under constant conditions but potentially less so in more variable environments. We measured the standard (=minimum) metabolic rate, maximum metabolic rate, and aerobic scope (=interval between standard and maximum rates) in juvenile brown trout (Salmo trutta) after 5weeks acclimation to each of three consecutive test temperatures (10, 13, and then 16°C) that simulated the warming conditions experienced throughout their first summer of growth. We found that metabolic rates are repeatable over a period of months under changing thermal conditions: individual trout exhibited consistent differences in all three metabolic traits across increasing temperatures. Initial among-individual differences in metabolism are thus likely to have significant consequences for fitness-related traits over key periods of their life history. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  1. Predicting how altering propagule pressure changes establishment rates of biological invaders across species pools.

    Science.gov (United States)

    Brockerhoff, Eckehard G; Kimberley, Mark; Liebhold, Andrew M; Haack, Robert A; Cavey, Joseph F

    2014-03-01

    Biological invasions resulting from international trade can cause major environmental and economic impacts. Propagule pressure is perhaps the most important factor influencing establishment, although actual arrival rates of species are rarely recorded. Furthermore, the pool of potential invaders includes many species that vary in their arrival rate and establishment potential. Therefore, we stress that it is essential to consider the size and composition of species pools arriving from source regions when estimating probabilities of establishment and effects of pathway infestation rates. To address this, we developed a novel framework and modeling approach to enable prediction of future establishments in relation to changes in arrival rate across entire species pools. We utilized 13 828 border interception records from the United States and New Zealand for 444 true bark beetle (Scolytinae) and longhorned beetle (Cerambycidae) species detected between 1949 and 2008 as proxies for arrival rates to model the relationship between arrival and establishment rates. Nonlinearity in this relationship implies that measures intended to reduce the unintended transport of potential invaders (such as phytosanitary treatments) must be highly effective in order to substantially reduce the rate of future invasions, particularly if trade volumes continue to increase.

  2. Changes in Heart Rate Variability in a Premature Infant with Hydrocephalus

    Directory of Open Access Journals (Sweden)

    Zuzana Uhrikova

    2012-11-01

    Full Text Available Objective - To define changes of heart rate variability in premature infant with hydrocephalus before and after drainage procedure. Study Design - The authors report a case of a premature infant with hydrocephalus with analysis of heart rate variability before and after drainage procedure. Three subsequent recordings of the electrocardiography and heart rate variability were done: the first at the age of 22 days before insertion of ventriculoperitoneal shunt, the second at the age of 36 days with functional shunt, the third at the age of 71 days (before discharge. Results - Before drainage operation, there was reduced heart rate variability in time and spectral domains, and sympathetic activity was dominant. After surgery, an increase in heart rate variability parameters was found, particularly with spectral analysis. The ratio of low-frequency/high-frequency band and relative power of the low-frequency band decreased, reflecting enhanced parasympathetic activity. Conclusion - Results of the heart rate variability analysis in a preterm infant with hydrocephalus before and after drainage procedure showed marked improvement in chronotropic cardiac regulation. Evaluation of heart rate variability in premature infants with hydrocephalus with increased intracranial pressure can be an additional method for monitoring of cardiac dysregulation and improvement of the cardiovascular control after successful drainage procedure.

  3. Change of Diurnal Heart Rate Patterns During Pregnancy and Lactation in Dogs (Canis familiaris

    Directory of Open Access Journals (Sweden)

    Häggström J

    2003-09-01

    Full Text Available Pregnancy and lactation involve great demands on the cardiovascular system. The purpose of this study was to investigate how the heart rate and diurnal heart rate pattern change when dogs become pregnant or lactate. Five clinically healthy female beagle dogs were mated, and delivered three to seven healthy puppies. The heart rate was investigated with 24-h ECG (Holter once during anoestrus, at 3, 5, 7 and 9 weeks of pregnancy, and at week 4 postpartum (lactation. However, at 9 weeks, the ECG could not be recorded for the fully 24 h in 4 of 5 dogs, because labour started and the dogs then appeared disturbed by the recordings. The results at this date are not included in the statistical comparison. The heart rate increased progressively during pregnancy and was still elevated at 4 weeks of lactation. During late pregnancy the difference in heart rates between daytime and nighttime became smaller, but the heart rate was significantly higher in daytime in all periods. In conclusion, the increased heart rates during pregnancy and lactation reflect increased demands on the cardiovascular system and may be important to consider in clinical practice.

  4. Accounting For Patients' Socioeconomic Status Does Not Change Hospital Readmission Rates.

    Science.gov (United States)

    Bernheim, Susannah M; Parzynski, Craig S; Horwitz, Leora; Lin, Zhenqiu; Araas, Michael J; Ross, Joseph S; Drye, Elizabeth E; Suter, Lisa G; Normand, Sharon-Lise T; Krumholz, Harlan M

    2016-08-01

    There is an active public debate about whether patients' socioeconomic status should be included in the readmission measures used to determine penalties in Medicare's Hospital Readmissions Reduction Program (HRRP). Using the current Centers for Medicare and Medicaid Services methodology, we compared risk-standardized readmission rates for hospitals caring for high and low proportions of patients of low socioeconomic status (as defined by their Medicaid status or neighborhood income). We then calculated risk-standardized readmission rates after additionally adjusting for patients' socioeconomic status. Our results demonstrate that hospitals caring for large proportions of patients of low socioeconomic status have readmission rates similar to those of other hospitals. Moreover, readmission rates calculated with and without adjustment for patients' socioeconomic status are highly correlated. Readmission rates of hospitals caring for patients of low socioeconomic status changed by approximately 0.1 percent with adjustment for patients' socioeconomic status, and only 3-4 percent fewer such hospitals reached the threshold for payment penalty in Medicare's HRRP. Overall, adjustment for socioeconomic status does not change hospital results in meaningful ways. Project HOPE—The People-to-People Health Foundation, Inc.

  5. Proteinuria and Rate of Change in Kidney Function in a Community-Based Population

    OpenAIRE

    Turin, Tanvir Chowdhury; James, Matthew; Ravani, Pietro; Tonelli, Marcello; Manns, Braden J.; Quinn, Robert; Jun, Min; Klarenbach, Scott; Hemmelgarn, Brenda R.

    2013-01-01

    Proteinuria identifies patients at risk for adverse clinical outcomes, but it is unclear whether proteinuria correlates with the rate of renal decline. We examined the association between proteinuria and rate of change in estimated GFR (eGFR) in a cohort of 638,150 adults from a province-wide registry in Alberta, Canada, who had a measure of proteinuria and three or more outpatient serum creatinine measurements over a period of ≥1 year. An adjusted sex-specific linear mixed-effects model was ...

  6. Effects of imipramine of the orthostatic changes in blood pressure, heart rate and plasma catecholamines

    DEFF Research Database (Denmark)

    Nielsen, J R; Johansen, Torben; Arentoft, A

    1983-01-01

    The effect of imipramine on the orthostatic changes in heart rate, blood pressure and plasma catecholamines were examined in six healthy male subjects on two occasions on high sodium balance (Na+ excretion greater than 120 mmol per day) and on low sodium balance (Na+ excretion less than 110 mmol...... per day), respectively. Orthostatic tests were carried out before and 2 h after ingestion of 150 mg imipramine hydrochloride. Imipramine caused a moderate increase in supine systolic blood pressure, and a pronounced increase in the rise in heart rate, when the subjects assumed erect position...

  7. Changes in transcriptional orientation are associated with increases in evolutionary rates of enterobacterial genes

    Directory of Open Access Journals (Sweden)

    Hsiung Chao

    2011-10-01

    Full Text Available Abstract Background Changes in transcriptional orientation (“CTOs” occur frequently in prokaryotic genomes. Such changes usually result from genomic inversions, which may cause a conflict between the directions of replication and transcription and an increase in mutation rate. However, CTOs do not always lead to the replication-transcription confrontation. Furthermore, CTOs may cause deleterious disruptions of operon structure and/or gene regulations. The currently existing CTOs may indicate relaxation of selection pressure. Therefore, it is of interest to investigate whether CTOs have an independent effect on the evolutionary rates of the affected genes, and whether these genes are subject to any type of selection pressure in prokaryotes. Methods Three closely related enterbacteria, Escherichia coli, Klebsiella pneumoniae and Salmonella enterica serovar Typhimurium, were selected for comparisons of synonymous (dS and nonsynonymous (dN substitution rate between the genes that have experienced changes in transcriptional orientation (changed-orientation genes, “COGs” and those that do not (same-orientation genes, “SOGs”. The dN/dS ratio was also derived to evaluate the selection pressure on the analyzed genes. Confounding factors in the estimation of evolutionary rates, such as gene essentiality, gene expression level, replication-transcription confrontation, and decreased dS at gene terminals were controlled in the COG-SOG comparisons. Results We demonstrate that COGs have significantly higher dN and dS than SOGs when a series of confounding factors are controlled. However, the dN/dS ratios are similar between the two gene groups, suggesting that the increase in dS can sufficiently explain the increase in dN in COGs. Therefore, the increases in evolutionary rates in COGs may be mainly mutation-driven. Conclusions Here we show that CTOs can increase the evolutionary rates of the affected genes. This effect is independent of the

  8. Asymmetric effects of exchange rate changes on the Malaysia-China commodity trade

    OpenAIRE

    Bahmani-Oskooee, Mohsen; Aftab, Muhammad

    2017-01-01

    Previous research that considered the response of the trade balance between Malaysia and China to exchange rate changes used a linear model and did not find any significant long-run link. Suspecting that the results suffer from aggregation bias as well as ignoring nonlinear adjustment of the exchange rate, we consider the trade balance of 59 industries that trade between the two countries and use a nonlinear ARDL model to show that almost 1/3rd of the industries are affected by ringgit deprec...

  9. Spin dynamics in a two-dimensional quantum gas

    DEFF Research Database (Denmark)

    Pedersen, Poul Lindholm; Gajdacz, Miroslav; Deuretzbacher, Frank

    2014-01-01

    We have investigated spin dynamics in a two-dimensional quantum gas. Through spin-changing collisions, two clouds with opposite spin orientations are spontaneously created in a Bose-Einstein condensate. After ballistic expansion, both clouds acquire ring-shaped density distributions with superimp......We have investigated spin dynamics in a two-dimensional quantum gas. Through spin-changing collisions, two clouds with opposite spin orientations are spontaneously created in a Bose-Einstein condensate. After ballistic expansion, both clouds acquire ring-shaped density distributions...... with nonlocal Einstein-Podolsky-Rosen entanglement....

  10. Implementation of intensity ratio change and line-of-sight rate change algorithms for imaging infrared trackers

    Science.gov (United States)

    Viau, C. R.

    2012-06-01

    The use of the intensity change and line-of-sight (LOS) change concepts have previously been documented in the open-literature as techniques used by non-imaging infrared (IR) seekers to reject expendable IR countermeasures (IRCM). The purpose of this project was to implement IR counter-countermeasure (IRCCM) algorithms based on target intensity and kinematic behavior for a generic imaging IR (IIR) seeker model with the underlying goal of obtaining a better understanding of how expendable IRCM can be used to defeat the latest generation of seekers. The report describes the Intensity Ratio Change (IRC) and LOS Rate Change (LRC) discrimination techniques. The algorithms and the seeker model are implemented in a physics-based simulation product called Tactical Engagement Simulation Software (TESS™). TESS is developed in the MATLAB®/Simulink® environment and is a suite of RF/IR missile software simulators used to evaluate and analyze the effectiveness of countermeasures against various classes of guided threats. The investigation evaluates the algorithm and tests their robustness by presenting the results of batch simulation runs of surface-to-air (SAM) and air-to-air (AAM) IIR missiles engaging a non-maneuvering target platform equipped with expendable IRCM as self-protection. The report discusses how varying critical parameters such track memory time, ratio thresholds and hold time can influence the outcome of an engagement.

  11. Spin transport properties in a double quantum ring with Rashba spin-orbit interaction

    Science.gov (United States)

    Naeimi, Azadeh S.; Eslami, Leila; Esmaeilzadeh, Mahdi; Abolhassani, Mohammad Reza

    2013-01-01

    We study spin-resolved electron transport in a double quantum ring in the presence of Rashba spin-orbit interaction and a magnetic flux using quantum waveguide theory. We show that, at the proper values of the system parameters such as the Rashba coupling constant, the radius of the rings, and the angle between the leads, the double quantum ring can act as a perfect electron spin-inverter with very high efficiency. Also, the double quantum ring can work as a spin switch. The spin polarization of transmitted electrons can be controlled and changed from -1 to +1 by using a magnetic flux.

  12. Correlating intraocular pressure, blood pressure, and heart rate changes after jogging.

    Science.gov (United States)

    Karabatakis, V E; Natsis, K I; Chatzibalis, T E; Lake, S L; Bisbas, I T; Kallinderis, K A; Stangos, N T

    2004-01-01

    To examine the effects of jogging on intraocular pressure (IOP), blood pressure (BP), and heart rate (HR). Twenty-nine healthy individuals-25 athletes and 4 untrained-were studied. IOP, systolic and diastolic BP, and HR were measured before and just after 20 minutes of jogging (submaximal--70%--aerobic exercise). IOP decreased after jogging. Only three individuals had unchanged IOP in one eye and one individual in both eyes. The IOP decrease (1 to 8 mmHg) was statistically significant (pjogging (systolic: 0 to 60 mmHg, statistically significant changes, pjogging. Changes in BP and HR values have no linear quantitative correlation with IOP decrease.

  13. Radiation-induced inheritable changes in the death-rate of cells

    International Nuclear Information System (INIS)

    Bychkovskaya, I.B.; Ochinskaya, G.K.

    1980-01-01

    By the use of an original technique (regeneration of individual lines from sister cells) it was demonstrated on various individually cultivated protozoa (Amoeba proteus, Paramecium caudatum and Climacostomum virens) that even weak direct and indirect radiation effects can induce an appreciable increase in the death-rate of descendants. After a certain dose threshold, the effect did not depend on the power of the attack and remained at the same level for as long as 3 years. The observed changes were qualitatively different from known types of inheritable changes leading to cell death

  14. A Hybrid Islanding Detection Technique Using Average Rate of Voltage Change and Real Power Shift

    DEFF Research Database (Denmark)

    Mahat, Pukar; Chen, Zhe; Bak-Jensen, Birgitte

    2009-01-01

    The mainly used islanding detection techniques may be classified as active and passive techniques. Passive techniques don't perturb the system but they have larger nondetection znes, whereas active techniques have smaller nondetection zones but they perturb the system. In this paper, a new hybrid...... technique is proposed to solve this problem. An average rate of voltage change (passive technique) has been used to initiate a real power shift (active technique), which changes the eal power of distributed generation (DG), when the passive technique cannot have a clear discrimination between islanding...

  15. Muon spin-relaxation measurements of spin-correlation decay in spin-glass AgMn

    International Nuclear Information System (INIS)

    Heffner, R.H.; Cooke, D.W.; Leon, M.; Schillaci, M.E.; MacLaughlin, D.E.; Gupta, L.C.

    1983-01-01

    The field (H) dependence of the muon longitudinal spin-lattice relaxation rate well below the spin-glass temperature in AgMn is found to obey an algebraic form given by (H)/sup nu-1/, with nu = 0.54 +- 0.05. This suggests that Mn spin correlations decay with time as t - /sup nu/, in agreement with mean field theories of spin-glass dynamics which yield nu less than or equal to 0.5. Near the glass temperature the agreement between the data and theory is not as good

  16. Magnetic Nanostructures Spin Dynamics and Spin Transport

    CERN Document Server

    Farle, Michael

    2013-01-01

    Nanomagnetism and spintronics is a rapidly expanding and increasingly important field of research with many applications already on the market and many more to be expected in the near future. This field started in the mid-1980s with the discovery of the GMR effect, recently awarded with the Nobel prize to Albert Fert and Peter Grünberg. The present volume covers the most important and most timely aspects of magnetic heterostructures, including spin torque effects, spin injection, spin transport, spin fluctuations, proximity effects, and electrical control of spin valves. The chapters are written by internationally recognized experts in their respective fields and provide an overview of the latest status.

  17. Capital accumulation, structural change and real exchange rate in a Keynesian-Structuralist growth model

    Directory of Open Access Journals (Sweden)

    Oreiro José Luis

    2015-01-01

    Full Text Available The aim of this paper is to show at theoretical level that maintaining a competitive real exchange rate positively affects the economic growth of developing countries by means of a Keynesian-Structuralist model that combines elements of Kaleckian growth models with the balance of payments constrained growth models pioneered developed by Thirlwall. In this setting, the level of real exchange rate is capable, due to its effect over capital accumulation, to induce a structural change in the economy, making endogenous income elasticities of exports and imports. For reasonable parameter values it is shown that in steady-state growth there is two long-run equilibrium values for real exchange rate, one that corresponds to an under-valued currency and another that corresponds to an over-valued currency. If monetary authorities run exchange rate policy in order to target a competitive level for real exchange rate, than under-valued equilibrium is stable and the economy will show a high growth rate in the long-run.

  18. Proteinuria and rate of change in kidney function in a community-based population.

    Science.gov (United States)

    Turin, Tanvir Chowdhury; James, Matthew; Ravani, Pietro; Tonelli, Marcello; Manns, Braden J; Quinn, Robert; Jun, Min; Klarenbach, Scott; Hemmelgarn, Brenda R

    2013-10-01

    Proteinuria identifies patients at risk for adverse clinical outcomes, but it is unclear whether proteinuria correlates with the rate of renal decline. We examined the association between proteinuria and rate of change in estimated GFR (eGFR) in a cohort of 638,150 adults from a province-wide registry in Alberta, Canada, who had a measure of proteinuria and three or more outpatient serum creatinine measurements over a period of ≥1 year. An adjusted sex-specific linear mixed-effects model was used to determine the rate of change in eGFR per year for patients with normal, mild, and heavy proteinuria, stratified by baseline kidney function (eGFR ≥90, 60-89.9, 45-59.9, 30-44.9, and 15-29.9 ml/min per 1.73 m(2)). In men, heavy proteinuria and a baseline eGFR of 45-59.9 ml/min per 1.73 m(2) correlated with a change in eGFR of -2.16 (95% confidence interval [CI], -2.37 to -1.95) ml/min per 1.73 m(2) per year, whereas mild proteinuria and a baseline eGFR of 30-44.9 ml/min per 1.73 m(2) correlated with a change in eGFR of -0.51 (95% CI, -0.70 to -0.32) ml/min per 1.73 m(2) per year. Similar trends were observed for female, elderly, and diabetic patients. Notably, normal protein levels and a lower baseline eGFR (15-29.9 ml/min per 1.73 m(2)) correlated with stable or improved renal function. In conclusion, our results suggest that proteinuria of increasing severity is associated with a faster rate of renal decline, regardless of baseline eGFR, and the combined effect should be considered in patients with CKD.

  19. Detection of change points in underlying earthquake rates, with application to global mega-earthquakes

    Science.gov (United States)

    Touati, Sarah; Naylor, Mark; Main, Ian

    2016-02-01

    The recent spate of mega-earthquakes since 2004 has led to speculation of an underlying change in the global `background' rate of large events. At a regional scale, detecting changes in background rate is also an important practical problem for operational forecasting and risk calculation, for example due to volcanic processes, seismicity induced by fluid injection or withdrawal, or due to redistribution of Coulomb stress after natural large events. Here we examine the general problem of detecting changes in background rate in earthquake catalogues with and without correlated events, for the first time using the Bayes factor as a discriminant for models of varying complexity. First we use synthetic Poisson (purely random) and Epidemic-Type Aftershock Sequence (ETAS) models (which also allow for earthquake triggering) to test the effectiveness of many standard methods of addressing this question. These fall into two classes: those that evaluate the relative likelihood of different models, for example using Information Criteria or the Bayes Factor; and those that evaluate the probability of the observations (including extreme events or clusters of events) under a single null hypothesis, for example by applying the Kolmogorov-Smirnov and `runs' tests, and a variety of Z-score tests. The results demonstrate that the effectiveness among these tests varies widely. Information Criteria worked at least as well as the more computationally expensive Bayes factor method, and the Kolmogorov-Smirnov and runs tests proved to be the relatively ineffective in reliably detecting a change point. We then apply the methods tested to events at different thresholds above magnitude M ≥ 7 in the global earthquake catalogue since 1918, after first declustering the catalogue. This is most effectively done by removing likely correlated events using a much lower magnitude threshold (M ≥ 5), where triggering is much more obvious. We find no strong evidence that the background rate of large

  20. Identification of neutron irradiation induced strain rate sensitivity change using inverse FEM analysis of Charpy test

    Science.gov (United States)

    Haušild, Petr; Materna, Aleš; Kytka, Miloš

    2015-04-01

    A simple methodology how to obtain additional information about the mechanical behaviour of neutron-irradiated WWER 440 reactor pressure vessel steel was developed. Using inverse identification, the instrumented Charpy test data records were compared with the finite element computations in order to estimate the strain rate sensitivity of 15Ch2MFA steel irradiated with different neutron fluences. The results are interpreted in terms of activation volume change.

  1. Identification of neutron irradiation induced strain rate sensitivity change using inverse FEM analysis of Charpy test

    Energy Technology Data Exchange (ETDEWEB)

    Haušild, Petr, E-mail: petr.hausild@fjfi.cvut.cz [Czech Technical University in Prague, Faculty of Nuclear Sciences and Physical Engineering, Department of Materials, Trojanova 13, 120 00 Praha 2 (Czech Republic); Materna, Aleš [Czech Technical University in Prague, Faculty of Nuclear Sciences and Physical Engineering, Department of Materials, Trojanova 13, 120 00 Praha 2 (Czech Republic); Kytka, Miloš [Czech Technical University in Prague, Faculty of Nuclear Sciences and Physical Engineering, Department of Materials, Trojanova 13, 120 00 Praha 2 (Czech Republic); Nuclear Research Institut, ÚJV Řež, a.s., Hlavní 130, Řež, 250 68 Husinec (Czech Republic)

    2015-04-15

    A simple methodology how to obtain additional information about the mechanical behaviour of neutron-irradiated WWER 440 reactor pressure vessel steel was developed. Using inverse identification, the instrumented Charpy test data records were compared with the finite element computations in order to estimate the strain rate sensitivity of 15Ch2MFA steel irradiated with different neutron fluences. The results are interpreted in terms of activation volume change.

  2. Understanding Rates of Marijuana Use and Consequences Among Adolescents in a Changing Legal Landscape

    OpenAIRE

    D’Amico, Elizabeth J.; Tucker, Joan S.; Pedersen, Eric R.; Shih, Regina A.

    2017-01-01

    Purpose of Review There is not one answer to address whether marijuana use has increased, decreased, or stayed the same given changes in state legalization of medical and non-medical marijuana in the USA. Recent Findings Evidence suggests some health benefits for medical marijuana; however, initiation of marijuana use is a risk factor for developing problem cannabis use. Though use rates have remained stable over recent years, about one in three 10th graders report marijuana use, most adolesc...

  3. Change in the rate and pattern of religious intermarriage in the Republic of Ireland

    OpenAIRE

    O'Leary, Richard

    1999-01-01

    Earlier attempts to estimate the rate and to establish the patterns of religious intermarriage in the Republic of Ireland have been limited by a lack of data. This paper presents new findings on intermarriage using previously unavailable Census of Population and survey data. In addition, it is argued that post-Vatican II changes in Roman Catholic Church teaching on intermarriage have had an observable impact on intermarriages with respect to the types of wedding ceremony and conversions.

  4. Crop failure rates in a geoengineered climate: impact of climate change and marine cloud brightening

    OpenAIRE

    Parkes, Ben; Challinor, A.; Nicklin, K.

    2015-01-01

    International audience; The impact of geoengineering on crops has to date been studied by examining mean yields. We present the first work focusing on the rate of crop failures under a geoengineered climate. We investigate the impact of a future climate and a potential geoengineering scheme on the number of crop failures in two regions, Northeastern China and West Africa. Climate change associated with a doubling of atmospheric carbon dioxide increases the number of crop failures in Northeast...

  5. Biomass is the main driver of changes in ecosystem process rates during tropical forest succession.

    Science.gov (United States)

    Lohbeck, Madelon; Poorter, Lourens; Martínez-Ramos, Miguel; Bongers, Frans

    2015-05-01

    Over half of the world's forests are disturbed, and the rate at which ecosystem processes recover after disturbance is important for the services these forests can provide. We analyze the drivers' underlying changes in rates of key ecosystem processes (biomass productivity, litter productivity, actual litter decomposition, and potential litter decomposition) during secondary succession after shifting cultivation in wet tropical forest of Mexico. We test the importance of three alternative drivers of ecosystem processes: vegetation biomass (vegetation quantity hypothesis), community-weighted trait mean (mass ratio hypothesis), and functional diversity (niche complementarity hypothesis) using structural equation modeling. This allows us to infer the relative importance of different mechanisms underlying ecosystem process recovery. Ecosystem process rates changed during succession, and the strongest driver was aboveground biomass for each of the processes. Productivity of aboveground stem biomass and leaf litter as well as actual litter decomposition increased with initial standing vegetation biomass, whereas potential litter decomposition decreased with standing biomass. Additionally, biomass productivity was positively affected by community-weighted mean of specific leaf area, and potential decomposition was positively affected by functional divergence, and negatively by community-weighted mean of leaf dry matter content. Our empirical results show that functional diversity and community-weighted means are of secondary importance for explaining changes in ecosystem process rates during tropical forest succession. Instead, simply, the amount of vegetation in a site is the major driver of changes, perhaps because there is a steep biomass buildup during succession that overrides more subtle effects of community functional properties on ecosystem processes. We recommend future studies in the field of biodiversity and ecosystem functioning to separate the effects of

  6. Inference of historical changes in migration rate from the lengths of migrant tracts

    DEFF Research Database (Denmark)

    Pool, John E; Nielsen, Rasmus

    2009-01-01

    After migrant chromosomes enter a population, they are progressively sliced into smaller pieces by recombination. Therefore, the length distribution of "migrant tracts" (chromosome segments with recent migrant ancestry) contains information about historical patterns of migration. Here we introduce...... a theoretical framework describing the migrant tract length distribution and propose a likelihood inference method to test demographic hypotheses and estimate parameters related to a historical change in migration rate. Applying this method to data from the hybridizing subspecies Mus musculus domesticus and M...

  7. Global changes alter soil fungal communities and alter rates of organic matter decomposition

    Science.gov (United States)

    Moore, J.; Frey, S. D.

    2016-12-01

    Global changes - such as warming, more frequent and severe droughts, increasing atmospheric CO2, and increasing nitrogen (N) deposition rates - are altering ecosystem processes. The balance between soil carbon (C) accumulation and decomposition is determined in large part by the activity and biomass of detrital organisms, namely soil fungi, and yet their sensitivity to global changes remains unresolved. We present results from a meta-analysis of 200+ studies spanning manipulative and observational field experiments to quantify fungal responses to global change and expected consequences for ecosystem C dynamics. Warming altered the functional soil microbial community by reducing the ratio of fungi to bacteria (f:b) total fungal biomass. Additionally, warming reduced lignolytic enzyme activity generally by one-third. Simulated N deposition affected f:b differently than warming, but the effect on fungal biomass and activity was similar. The effect of N-enrichment on f:b was contingent upon ecosystem type; f:b increased in alpine meadows and heathlands but decreased in temperate forests following N-enrichment. Across ecosystems, fungal biomass marginally declined by 8% in N-enriched soils. In general, N-enrichment reduced fungal lignolytic enzyme activity, which could explain why soil C accumulates in some ecosystems following warming and N-enrichment. Several global change experiments have reported the surprising result that soil C builds up following increases in temperature and N deposition rates. While site-specific studies have examined the role of soil fungi in ecosystem responses to global change, we present the first meta-analysis documenting general patterns of global change impacts on soil fungal communities, biomass, and activity. In sum, we provide evidence that soil microbial community shifts and activity plays a large part in ecosystem responses to global changes, and have the potential to alter the magnitude of the C-climate feedback.

  8. Life Change Units (LCU Rating as Stressors in Iranian Hospitals’ Nurses

    Directory of Open Access Journals (Sweden)

    Hossein Dargahi

    2012-02-01

    Full Text Available Healthcare workers suffer from work-related or occupational stress. This can lead to severe distress, burnout or physical illness, and finally to decrease quality of work life and services provision. Nurses must be aware of retential stressors, because they add to the cumulative effect of other stressful events. Holmes and Rahe both found a relationship between life change unit as stressors and health changes. This research reported here aims to measure the life change units as stressors among Iranian Hospitals Nurses by LCU rating. A cross - sectional, descriptive and analytical study was conducted among 389 nurses working in 15 teaching hospitals in Tehran, Iran. The respondents were asked to select each of 54 events that cause stress ranked in order of their life change units developed by Holmes and Rahe as stress scale. Before beginning the main study, the reliability and coincidental validity was performed. All data were analyzed using SPSS for windows version 18, t-test, Anova statistical methods. Approximately, half of the nurses associated major mortgage, foreclosure of mortgage or loan. More than 50% of the Iranian nurses had 150-300 and more than 300 LCU rating which had the chance to expose to extremely serious risk to health.Iranian hospitals nurses suffer from stress that caused by Life Change Units organizational factors such as change in the financial state, change in the work environment and major mortgage. We recommend to Iranian nursing policy-makers to choose strategies to help nurses cope effectively with workplace stressors. Nursing managers and / or nursing management should develop strategies to address and improve the quality of working conditions for nurses in the hospitals. Providing educational and career prospects can contribute to decrease nurses occupational stress level, the maintaining their work ability.

  9. When the World Changes in Your Hands: Similarity Ratings of Objects Morphing during Active Exploration

    Directory of Open Access Journals (Sweden)

    Haemy Lee

    2012-10-01

    Full Text Available View-based theories of object recognition posit that coherent object representations are formed by linking together successive views of an actively explored object. This linking process relies on the assumption that the object does not change during exploration. Here, we test how object representations might be influenced when the shape of the object changes slowly during exploration. In our experiment, participants rated the similarity of two novel, 3D objects, whose shape was parametrically defined. Seventeen participants explored each object for 10 sec on an iPad which afforded natural and efficient interaction. The experiment contained a baseline condition, in which two objects of varying parameter-differences were presented, and a morphing condition, in which the first of the two objects slowly morphed during active exploration, making the objects more similar. Interestingly, no participant was aware of this morphing manipulation. Comparing baseline and morph trials, however, we found significantly higher similarity ratings during morphing [F(1,16 = 84.79, p < .001]. Furthermore, correlations between similarity ratings and differences in object parameters were high for the baseline condition (r = −.64, with smaller parameter differences being perceived as more similar. Interestingly, in the morphing condition correlations were lower for parameter differences after the morph (r = −.22, but remained high for differences before (r = −.47 and during morphing (r = −.50. In conclusion, similarity ratings in the baseline condition captured the complex parameter space well. Although participants did not notice the changing shape, morphing did systematically bias the ratings. Interestingly, similarity judgments correlated better in the initial exploration phase, suggesting a capacity limit for view integration of complex shapes.

  10. Heart rate changes during the Valsalva maneuver in patients with isolated aortic insufficiency

    Directory of Open Access Journals (Sweden)

    Navarro A.E.

    1997-01-01

    Full Text Available To determine the possible relationship between left ventricular dilatation and heart rate changes provoked by the Valsalva maneuver (Valsalva ratio, we studied 9 patients with isolated chronic aortic insufficiency. Left ventricular systolic function was assessed by two-dimensional echocardiography and cardiac catheterization. All patients were asymptomatic (functional class I of the New York Heart Association. The left ventricular internal diameters and volumes were significantly increased in all patients. The asymptomatic patients had either normal or slightly depressed ejection fraction (EF>0.40. The Valsalva ratio of these asymptomatic patients showed no significant correlation with the left ventricular volumes or with the left ventricular ejection fraction. In other words, parasympathetic heart rate control, as expressed by the Valsalva ratio, was normal in the asymptomatic patients with left ventricular dilatation and preserved left ventricular ejection fraction. Therefore, left ventricular dilatation may not be the major mechanism responsible for the abnormal parasympathetic heart rate control of patients with acquired heart disease

  11. The Reaction of Private Spending and Market Interest Rates to the Changes in Public Spending

    Directory of Open Access Journals (Sweden)

    Przekota Grzegorz

    2016-01-01

    Full Text Available Expansionary fiscal policy is mired in controversy. Its proponents suggest that during recession, it stimulates investors’ activity and has a stabilizing effect on economic growth. However, its opponents point to the costs associated with the budget deficit and public debt handling. Increased public spending may result in an increase in the interest rates, which may, in turn, hinder private investment and weaken the multiplier effect of public spending. The following study examines how private spending and market interest rates reacted to changes in public spending in Poland. The study has shown that public spending stimulates private spending, which is consistent with the Keynesian model, but it also leads to an increase in market interest rates, which is consistent with the neoclassical model.

  12. Flexibility in metabolic rate confers a growth advantage under changing food availability.

    Science.gov (United States)

    Auer, Sonya K; Salin, Karine; Rudolf, Agata M; Anderson, Graeme J; Metcalfe, Neil B

    2015-09-01

    1. Phenotypic flexibility in physiological, morphological and behavioural traits can allow organisms to cope with environmental challenges. Given recent climate change and the degree of habitat modification currently experienced by many organisms, it is therefore critical to quantify the degree of phenotypic variation present within populations, individual capacities to change and what their consequences are for fitness. 2. Flexibility in standard metabolic rate (SMR) may be particularly important since SMR reflects the minimal energetic cost of living and is one of the primary traits underlying organismal performance. SMR can increase or decrease in response to food availability, but the consequences of these changes for growth rates and other fitness components are not well known. 3. We examined individual variation in metabolic flexibility in response to changing food levels and its consequences for somatic growth in juvenile brown trout (Salmo trutta). 4. SMR increased when individuals were switched to a high food ration and decreased when they were switched to a low food regime. These shifts in SMR, in turn, were linked with individual differences in somatic growth; those individuals that increased their SMR more in response to elevated food levels grew fastest, while growth at the low food level was fastest in those individuals that depressed their SMR most. 5. Flexibility in energy metabolism is therefore a key mechanism to maximize growth rates under the challenges imposed by variability in food availability and is likely to be an important determinant of species' resilience in the face of global change. © 2015 The Authors. Journal of Animal Ecology published by John Wiley & Sons Ltd on behalf of British Ecological Society.

  13. The management and outcome of documented intraoperative heart rate-related electrocardiographic changes.

    Science.gov (United States)

    Hobai, Ion A; Gauran, Cosmin; Chitilian, Hovig V; Ehrenfeld, Jesse M; Levinson, John; Sandberg, Warren S

    2011-10-01

    The authors analyzed surgical cases in which electrocardiographic (ECG) signs of cardiac ischemia were noted to be precipitated by increases in heart rate (ie, heart rate-related ECG changes [REC]). The authors aimed to find REC incidence, specificity for coronary artery disease (CAD), and the outcome associated with different management strategies. A retrospective review. A university hospital, tertiary care. Patients undergoing surgery under anesthesia. A chart review. The authors searched 158,252 anesthesia electronic records for comments noting REC (ie, ST-segment or T-wave changes). After excluding cases with potentially confounding conditions (eg, hypotension, hyperkalemia, and so on), 26 cases were analyzed. REC commonly was precipitated by anesthesia-related events (ie, intubation, extubation, and treatment of bradycardia). In 24 cases, REC was managed by prompt heart rate reduction using β-blocker agents, opioids, and/or cardioversion in the addition to the removal of stimulus. Only 1 case had a copy of the ECG printed. Two cases were aborted, 1 was shortened and 23 proceeded without change. Postoperative troponin T levels were checked, and cardiology consultation was obtained in selected cases and led to further cardiac evaluation in 6 cases. Postoperative myocardial infarction developed in only 1 patient in whom the ECG changes were allowed to persist throughout the case. This incidence of reported REC was much lower than the previously reported incidence of ischemia-related ECG changes, suggesting that the largest proportion of events go unnoticed. In many patients, subsequent cardiology workup did not confirm the existence of clinically significant CAD. Copyright © 2011 Elsevier Inc. All rights reserved.

  14. Spin Interference in Rectangle Loop Based on Rashba and Dresselhaus Spin-Orbit Interactions

    International Nuclear Information System (INIS)

    Jia-Ting, Ni; Bin, Chen; Xiao-Wan, Liang; Koga, T.

    2009-01-01

    We demonstrate the amplitude and spin polarization of AAS oscillation changing with Rashba spin-orbit interaction (SOI) and Dresselhaus SOI. The amplitude and spin polarization of AB oscillation changing with Rashba SOI and Dresselhaus SOI are demonstrated as well. The ideal quasi-one-dimensional square loop does not exist in reality, therefore to match the experiment better we should consider the shape of the rectangle loop in theory

  15. Control of spin injection by direct current in lateral spin valves

    OpenAIRE

    Casanova, Fèlix; Sharoni, Amos; Erekhinsky, Mikhail; Schuller, Ivan K.

    2008-01-01

    The spin injection and accumulation in metallic lateral spin valves with transparent interfaces is studied using d.c. injection current. Unlike a.c.-based techniques, this allows investigating the effects of the direction and magnitude of the injected current. We find that the spin accumulation is reversed by changing the direction of the injected current, whereas its magnitude does not change. The injection mechanism for both current directions is thus perfectly symmetric, leading to the sam...

  16. Relevant microclimate for determining the development rate of malaria mosquitoes and possible implications of climate change.

    Science.gov (United States)

    Paaijmans, Krijn P; Imbahale, Susan S; Thomas, Matthew B; Takken, Willem

    2010-07-09

    The relationship between mosquito development and temperature is one of the keys to understanding the current and future dynamics and distribution of vector-borne diseases such as malaria. Many process-based models use mean air temperature to estimate larval development times, and hence adult vector densities and/or malaria risk. Water temperatures in three different-sized water pools, as well as the adjacent air temperature in lowland and highland sites in western Kenya were monitored. Both air and water temperatures were fed into a widely-applied temperature-dependent development model for Anopheles gambiae immatures, and subsequently their impact on predicted vector abundance was assessed. Mean water temperature in typical mosquito breeding sites was 4-6 degrees C higher than the mean temperature of the adjacent air, resulting in larval development rates, and hence population growth rates, that are much higher than predicted based on air temperature. On the other hand, due to the non-linearities in the relationship between temperature and larval development rate, together with a marginal buffering in the increase in water temperature compared with air temperature, the relative increases in larval development rates predicted due to climate change are substantially less. Existing models will tend to underestimate mosquito population growth under current conditions, and may overestimate relative increases in population growth under future climate change. These results highlight the need for better integration of biological and environmental information at the scale relevant to mosquito biology.

  17. Rate Constant Change of Photo Reaction of Bacteriorhodopsin Observed in Trimeric Molecular System.

    Science.gov (United States)

    Tsujiuchi, Yutaka; Masumoto, Hiroshi; Goto, Takashi

    2016-04-01

    To elucidate the time evolution of photo reaction of bacteriorhodopsin in glycerol mixed purple membrane at around 196 K under irradiation by red light, a kinetic model was constructed. The change of absorption with irradiation at times of 560 nm and 412 nm was analyzed for the purpose of determining reaction rates of photo reaction of bacteriorhodopsin and its product M intermediate. In this study it is shown that reaction rates of conversion from bacteriorhodopsin to the M intermediate can be explained by a set of linear differential equations. This model analysis concludes that bacteriorhodopsin in which constitutes a trimer unit with other two bacteriorhodopsin molecules changes into M intermediates in the 1.73 of reaction rate, in the initial step, and according to the number of M intermediate in a trimer unit, from three to one, the reaction rate of bacteriorhodopsin into M intermediates smaller as 1.73, 0.80, 0.19 which caused by influence of inter-molecular interaction between bacteriorhodopsin.

  18. Changes in Muscle Activation Patterns when Running Step Rate is Increased

    Science.gov (United States)

    Chumanov, Elizabeth S.; Wille, Christa M.; Michalski, Max P.; Heiderscheit, Bryan C.

    2012-01-01

    Running with a step rate 5–10% greater than one’s preferred can substantially reduce lower extremity joint moments and powers, and has been suggested as a possible strategy to aid in running injury management. The purpose of this study was to examine how neuromuscular activity changes with an increase in step rate during running. Forty-five injury-free, recreational runners participated in this study. Three-dimensional motion, ground reaction forces, and electromyography (EMG) of 8 muscles (rectus femoris, vastus lateralis, medial gastrocnemius, tibialis anterior, medial and lateral hamstrings, and gluteus medius and maximus) were recorded as each subject ran at their preferred speed for three different step rate conditions: preferred, +5% and +10% of preferred. Outcome measures included mean normalized EMG activity for each muscle at specific periods during the gait cycle. Muscle activities were found to predominantly increase during late swing, with no significant change in activities during the loading response. This increased muscle activity in anticipation of foot-ground contact likely alters the landing posture of the limb and the subsequent negative work performed by the joints during stance phase. Further, the increased activity observed in the gluteus maximus and medius suggests running with a greater step rate may have therapeutic benefits to those with anterior knee pain. PMID:22424758

  19. Incision rate changes in the upper Var River catchment, southern French Alps: from observations to models.

    Science.gov (United States)

    Petit, Carole; Rolland, Yann; Goren, Liran; Bourlès, Didier; Braucher, Régis; Saillard, Marianne; Cassol, Davide

    2017-04-01

    Cosmic Ray Exposure (CRE) dating on river polished surfaces from gorges located in the Var River catchment (Southern French Alps) reveals high incision rate pulses (>10 mm.yr-1) related with climate changes, and in particular with glacial-interglacial transitions. In addition, they show that the onset of the last deglaciation in this area occurred shortly after the Last Glacial Maximum (LGM), i.e. 16-19 ka ago. Extrapolating these results to longer time scales suggests that the post 140 ka history of this landscape was dominated by fluvial incision. Inverse models based on the stream power law are then used to determine uplift rate variations in several small tributaries of this catchment with respect to the main channel. These inverse models show that all tributaries have consistent incision rate histories with alternating high and low values, and a comparison with global temperature curves shows that these variations significantly correlate with quaternary climate changes. We suggest that during warm periods, a wave of regressive erosion propagates in the main channel, while its tributaries deeply incise their substratum to catch up with the falling base-level. We then perform forward models of river incision and simulate the incision of the main channel system over a time span of 600 ka. This model allows us to extract time and space incision rate variations along the Tinée River channel (the largest tributary of the Var River). With a background of a few mm.yr-1, incision rate can increase up to more than 10 mm.yr-1 during short episodes, in agreement with CRE dating. The part of the channel located between 12 and 20 km downstream from the source has undergone several periods of rapid incision rates, which could explain the steep hillslopes and the triggering of a landslide 10 kyr ago.

  20. Two Wien Filter Spin Flipper

    Energy Technology Data Exchange (ETDEWEB)

    Grames, J M; Benesch, J F; Clark, J; Hansknecht, J; Kazimi, R; Machie, D; Poelker, M; Stutzman, M L; Suleiman, R

    2011-03-01

    A new 4pi spin manipulator composed of two Wien filters oriented orthogonally and separated by two solenoids has been installed at the CEBAF/Jefferson Lab photoinjector. The new spin manipulator is used to precisely set the electron spin direction at an experiment in any direction (in or out of plane of the accelerator) and provides the means to reverse, or flip, the helicity of the electron beam on a daily basis. This reversal is being employed to suppress systematic false asymmetries that can jeopardize challenging parity violation experiments that strive to measure increasingly small physics asymmetries [*,**,***]. The spin manipulator is part of the ultra-high vacuum polarized electron source beam line and has been successfully operated with 100keV and 130keV electron beam at high current (>100 microAmps). A unique feature of the device is that spin-flipping requires only the polarity of one solenoid magnet be changed. Performance characteristics of the Two Wien Filter Spin Flipper will be summarized.

  1. Investigations of effect of phase change mass transfer rate on cavitation process with homogeneous relaxation model

    Energy Technology Data Exchange (ETDEWEB)

    He, Zhixia; Zhang, Liang; Saha, Kaushik; Som, Sibendu; Duan, Lian; Wang, Qian

    2017-12-01

    The super high fuel injection pressure and micro size of nozzle orifice has been an important development trend for the fuel injection system. Accordingly, cavitation transient process, fuel compressibility, amount of noncondensable gas in the fuel and cavitation erosion have attracted more attention. Based on the fact of cavitation in itself is a kind of thermodynamic phase change process, this paper takes the perspective of the cavitation phase change mass transfer process to analyze above mentioned phenomenon. The two-phase cavitating turbulent flow simulations with VOF approach coupled with HRM cavitation model and U-RANS of standard k-ε turbulence model were performed for investigations of cavitation phase change mass transfer process. It is concluded the mass transfer time scale coefficient in the Homogenous Relaxation Model (HRM) representing mass transfer rate should tend to be as small as possible in a condition that ensured the solver stable. At very fast mass transfer rate, the phase change occurs at very thin interface between liquid and vapor phase and condensation occurs more focused and then will contribute predictably to a more serious cavitation erosion. Both the initial non-condensable gas in fuel and the fuel compressibility can accelerate the cavitation mass transfer process.

  2. Adaptive changes in basal metabolic rate and thermogenesis in chronic undernutrition

    International Nuclear Information System (INIS)

    Shetty, P.S.

    1993-01-01

    Metabolic adaptation during chronic undernutrition represents a complex integration of several processes which affect the total energy expenditure of the individual. Basal metabolic rate (BMR) is reduced; reductions in BMR per unit fat free mass (FFM) is difficult to demonstrate. BMR changes in undernutrition reflect the low body weight as well as alterations in the composition of the FFM; more specifically changes in the ratio of viscera to muscle compartments of the FFM. Thermogenic responses to norepinephrine are transiently suppressed but recover rapidly on repeated stimulation. Dietary thermogenesis is enhanced possible the result of increases in tissue synthesis within the body. Changes in BMR and thermogenesis suggestive of an increase in metabolic efficiency is thus difficult to demonstrate in chronic undernutrition. (author). 15 refs, 2 figs, 7 tabs

  3. Adiabatic analysis of collisions. III. Remarks on the spin model

    International Nuclear Information System (INIS)

    Fano, U.

    1979-01-01

    Analysis of a spin-rotation model illustrates how transitions between adiabatic channel states stem from the second, rather than from the first, rate of change of these states, provided that appropriate identification of channels and scaling of the independent variable are used. These remarks, like the earlier development of a post-adiabatic approach, aim at elucidating the surprising success of approximate separation of variables in the treatment of complex mechanical systems

  4. Decoherence dynamics of a single spin versus spin ensemble

    NARCIS (Netherlands)

    Dobrovitski, V.V.; Feiguin, A.E.; Awschalom, D.D.; Hanson, R.

    2008-01-01

    We study decoherence of central spins by a spin bath, focusing on the difference between measurement of a single central spin and measurement of a large number of central spins (as found in typical spin-resonance experiments). For a dilute spin bath, the single spin demonstrates Gaussian

  5. Measures of and changes in heart rate variability in pediatric heart transplant recipients.

    Science.gov (United States)

    Williams, T; Tang, X; Gilmore, G; Gossett, J; Knecht, K R

    2017-06-01

    Heart rate variability is primarily regulated by the autonomic nervous system. Heart transplant recipients undergo surgical denervation of the graft, which results in interruption of autonomic innervation with resultant diminished heart rate variability although some degree of autonomic control may return. This study aimed to characterize heart rate variability in this population. We report a retrospective review of Holter monitor data from transplanted patients between 2005 and 2013. Studies with significant atrial or ventricular arrhythmias were excluded. We evaluated changes over time and compared standard time domain measures to published pediatric normal values. Data were reviewed from 582 monitors in 152 patients. We found that pediatric heart transplant recipients have lower heart rate variability than age-matched controls and higher average heart rate in recipients older than 3 years. There is an increase in measures of variability through the first 3 years post-transplant with plateau after that time. Surgical technique in regard to interruption of the vagus nerve does not affect variability, nor does underlying congenital vs acquired heart disease. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  6. Effect of phase change material on the heat transfer rate of different building materials

    Science.gov (United States)

    Hasan, Mushfiq; Alam, Shahnur; Ahmed, Dewan Hasan

    2017-12-01

    Phase change material (PCM) is widely known as latent heat storage. A comprehensive study is carried out to investigate the effect of PCM on heat transfer rate of building materials. Paraffin is used as PCM along with different conventional building materials to investigate the heat transfer rate from the heated region to the cold region. PCM is placed along with the three different types of building materials like plaster which is well know building material in urban areas and wood and straw which are commonly used in rural areas for roofing as well as wall panel material and investigated the heat transfer rate. An experimental setup was constructed with number of rectangular shape aluminum detachable casing (as cavity) and placed side by side. Series of rectangular cavity filled with convent ional building materials and PCM and these were placed in between two chambers filled with water at different temperature. Building materials and PCM were placed in different cavities with different combinations and investigated the heat transfer rate. The results show that using the PCM along with other building materials can be used to maintain lower temperature at the inner wall and chamber of the cold region. Moreover, the placement or orientation of the building materials and PCM make significant contribution to heat transfer rate from the heated zone to the cold zone.

  7. Using behavior change frameworks to improve healthcare worker influenza vaccination rates: A systematic review.

    Science.gov (United States)

    Corace, Kimberly M; Srigley, Jocelyn A; Hargadon, Daniel P; Yu, Dorothy; MacDonald, Tara K; Fabrigar, Leandre R; Garber, Gary E

    2016-06-14

    Influenza vaccination of healthcare workers (HCW) is important for protecting staff and patients, yet vaccine coverage among HCW remains below recommended targets. Psychological theories of behavior change may help guide interventions to improve vaccine uptake. Our objectives were to: (1) review the effectiveness of interventions based on psychological theories of behavior change to improve HCW influenza vaccination rates, and (2) determine which psychological theories have been used to predict HCW influenza vaccination uptake. MEDLINE, EMBASE, CINAHL, PsycINFO, The Joanna Briggs Institute, SocINDEX, and Cochrane Database of Systematic Reviews were searched for studies that applied psychological theories of behavior change to improve and/or predict influenza vaccination uptake among HCW. The literature search yielded a total of 1810 publications; 10 articles met eligibility criteria. All studies used behavior change theories to predict HCW vaccination behavior; none evaluated interventions based on these theories. The Health Belief Model was the most frequently employed theory to predict influenza vaccination uptake among HCW. The remaining predictive studies employed the Theory of Planned Behavior, the Risk Perception Attitude, and the Triandis Model of Interpersonal Behavior. The behavior change framework constructs were successful in differentiating between vaccinated and non-vaccinated HCW. Key constructs identified included: attitudes regarding the efficacy and safety of influenza vaccination, perceptions of risk and benefit to self and others, self-efficacy, cues to action, and social-professional norms. The behavior change frameworks, along with sociodemographic variables, successfully predicted 85-95% of HCW influenza vaccination uptake. Vaccination is a complex behavior. Our results suggest that psychological theories of behavior change are promising tools to increase HCW influenza vaccination uptake. Future studies are needed to develop and evaluate novel

  8. Spin-crossover materials properties and applications

    CERN Document Server

    Halcrow, Malcolm A

    2013-01-01

    The phenomenon of spin-crossover has a large impact on the physical properties of a solid material, including its colour, magnetic moment, and electrical resistance. Some materials also show a structural phase change during the transition. Several practical applications of spin-crossover materials have been demonstrated including display and memory devices, electrical and electroluminescent devices, and MRI contrast agents. Switchable liquid crystals, nanoparticles, and thin films of spin-crossover materials have also been achieved. Spin-Crossover Materials: Properties and Applicat

  9. Spin-polarized spin excitation spectroscopy

    International Nuclear Information System (INIS)

    Loth, Sebastian; Lutz, Christopher P; Heinrich, Andreas J

    2010-01-01

    We report on the spin dependence of elastic and inelastic electron tunneling through transition metal atoms. Mn, Fe and Cu atoms were deposited onto a monolayer of Cu 2 N on Cu(100) and individually addressed with the probe tip of a scanning tunneling microscope. Electrons tunneling between the tip and the substrate exchange energy and spin angular momentum with the surface-bound magnetic atoms. The conservation of energy during the tunneling process results in a distinct onset threshold voltage above which the tunneling electrons create spin excitations in the Mn and Fe atoms. Here we show that the additional conservation of spin angular momentum leads to different cross-sections for spin excitations depending on the relative alignment of the surface spin and the spin of the tunneling electron. For this purpose, we developed a technique for measuring the same local spin with a spin-polarized and a non-spin-polarized tip by exchanging the last apex atom of the probe tip between different transition metal atoms. We derive a quantitative model describing the observed excitation cross-sections on the basis of an exchange scattering process.

  10. Magnons, Spin Current and Spin Seebeck Effect

    Science.gov (United States)

    Maekawa, Sadamichi

    2012-02-01

    When metals and semiconductors are placed in a temperature gradient, the electric voltage is generated. This mechanism to convert heat into electricity, the so-called Seebeck effect, has attracted much attention recently as the mechanism for utilizing wasted heat energy. [1]. Ferromagnetic insulators are good conductors of spin current, i.e., the flow of electron spins [2]. When they are placed in a temperature gradient, generated are magnons, spin current and the spin voltage [3], i.e., spin accumulation. Once the spin voltage is converted into the electric voltage by inverse spin Hall effect in attached metal films such as Pt, the electric voltage is obtained from heat energy [4-5]. This is called the spin Seebeck effect. Here, we present the linear-response theory of spin Seebeck effect based on the fluctuation-dissipation theorem [6-8] and discuss a variety of the devices. [4pt] [1] S. Maekawa et al, Physics of Transition Metal Oxides (Springer, 2004). [0pt] [2] S. Maekawa: Nature Materials 8, 777 (2009). [0pt] [3] Concept in Spin Electronics, eds. S. Maekawa (Oxford University Press, 2006). [0pt] [4] K. Uchida et al., Nature 455, 778 (2008). [0pt] [5] K. Uchida et al., Nature Materials 9, 894 (2010) [0pt] [6] H. Adachi et al., APL 97, 252506 (2010) and Phys. Rev. B 83, 094410 (2011). [0pt] [7] J. Ohe et al., Phys. Rev. B (2011) [0pt] [8] K. Uchida et al., Appl. Phys. Lett. 97, 104419 (2010).

  11. Turnover rate of cerebrospinal fluid in female sheep: changes related to different light-dark cycles

    Directory of Open Access Journals (Sweden)

    Malpaux Benoit

    2009-08-01

    Full Text Available Abstract Background Sheep are seasonal breeders. The key factor governing seasonal changes in the reproductive activity of the ewe is increased negative feedback of estradiol at the level of the hypothalamus under long-day conditions. It has previously been demonstrated that when gonadotropin secretions are inhibited during long days, there is a higher concentration of estradiol in the cerebrospinal fluid (CSF than during short days. This suggests an involvement of the CSF and choroid plexus in the neuroendocrine regulatory loop, but the mechanisms underlying this phenomenon remain unknown. One possible explanation of this difference in hormonal content is an effect of concentration or dilution caused by variations in CSF secretion rate. The aim of this study was thus to investigate changes in the CSF turnover rate related to light-dark cycles. Methods The turnover rate of the CSF was estimated by measuring the time taken for the recovery of intraventricular pressure (IVP after removal of a moderate volume (0.5 to 2 ml of CSF (slope in mmHg/min. The turnover rate was estimated three times in the same group of sheep: during a natural period of decreasing day-length corresponding to the initial period when gonadotropin activity is stimulated (SG1, during a long-day inhibitory period (IG, and finally during a short-day stimulatory period (SG2. Results The time taken and the speed of recovery of initial IVP differed between groups: 8 min 30 sec, 0.63 ± 0.07 mmHg/min(SG1, 11 min 1 sec, 0.38 ± 0.06 mmHg/min (IG and 9 min 0 sec, 0.72 ± 0.15 mmHg/min (SG2. Time changes of IVP differed between groups (ANOVA, p p p = 0.41, but was significantly different from IG: 71.33 ± 16.59 μl/min (p = 0.016. Conclusion This study shows that the turnover rate of CSF in ewes changes according to the light-dark cycle; it is increased during short day periods and reduced in long day periods. This phenomenon could account for differences in hormonal concentrations in

  12. Trade Adjustments to Exchange Rate Changes by Japanese Manufacturing MNEs: Intra-firm and arm's length transactions

    OpenAIRE

    ANDO Mitsuyo; KIMURA Fukunari

    2013-01-01

    This paper examines how Japanese manufacturing multinational enterprises (MNEs) adjust to exchange rate changes. Using the micro-data of Japanese manufacturing MNEs from 1994 to 2010, we find that exports tend to respond to exchange rate changes, in particular when wholly or majority-owned affiliates are dominant among their foreign affiliates and when intra-firm trade ratios are higher. Moreover, the responsiveness to exchange rate changes is higher for intra-firm exports than for total expo...

  13. The Berry phase in frustrated spin glass

    International Nuclear Information System (INIS)

    Banerjee, D.

    2007-12-01

    In this letter we have pointed out that frustration in spin glass is realized through the Berry phase due to the conflict between the spin ordering in the course of parallel transport. We came to the point that the Berry phase depicting the chiral change of helicity of a quantized spinor is prominent only in the presence of frustration. (author)

  14. Linking Changes in Contraceptive Use to Declines in Teen Pregnancy Rates

    Directory of Open Access Journals (Sweden)

    Jennifer Manlove

    2015-12-01

    Full Text Available Using a unique microsimulation tool, Teen FamilyScape, the present study explores how changes in the mix of contraceptive methods used by teens contributed to the decline in the U.S. teen pregnancy rate between 2002 and 2010. Results indicate that changes in contraceptive use contributed to approximately half of the decline in the teen pregnancy rate during this time period (48% and that a little more than half of this “contraceptive effect” was due to an increase in teen condom use (58%. The remaining share of the contraceptive effect can be attributed to an increase in the use of more effective hormonal (pill, patch, ring and long-acting reversible contraceptive (LARC/injectable methods (Intrauterine Devices (IUD, implant and injectable. Results from an additional counterfactual analysis suggest that the contraceptive effect was driven by the fact that the percentage of teens using no birth control fell during the study time period, rather than by the fact that some teens switched from less effective methods (condoms to more effective hormonal and LARC/injectable methods. However, very high typical use failure rates for teen condom users suggest the need for a two-pronged approach for continuing reductions in teen pregnancy for sexually active teens: first, targeting the youth most at risk of not using contraception and helping them choose contraception, and second, increasing the effectiveness of method use among existing contraceptors.

  15. Determination of Hemodynamic Changes on Heart Rate for Assessment of Orthostatic Intolerance in Older People

    Energy Technology Data Exchange (ETDEWEB)

    Hortelano Rubio, M.; Reilly, R.B.; Cervigón Abad, R.

    2016-07-01

    Introduction.- The aim of our study was to assess the hemodynamic changes that occur in symptomatic Orthostatic Intolerance (OI) patients, at the starting of exercise and recovery stages during six minutes walking distance test. Materials.- We analysed 65 older subjects, of whom 42 were women. The participants were carried out the Active Stand Protocol. The records were divided into: Phase 1 (pre-exercise), Phase 2 (starting of exercise), Phase 3 (active), Phase 4 (recovery) and Phase 5 (prost-exercise). Methods.- The averages and differences of heart rate (HR) between Phase 1, Phase 3 and Phase 5 were calculated. In the same way, duration before stabilization from passive to active stages (Phase 2) and from active to passive stages (Phase 4) were calculated. The máximum and mínimum values achieved in these time series and the difference between these values were also calculated. Results.- Results showed that the symptomatic OI patients employed more time to reach the active phase tan the asymptomatic OI participants. Moreover, the symptomatic OI participants showed higher mínimum heart rate values at the starting of exercise and recovery stages. However, the asymptomatic OI group illustrated a higher difference between the máximum and mínimum heart rate values in these stages with a significance p=0.003 and p=0.007, respectivecly. Conclusion.- This study provides important information on hemodynamic parameters and can be helpful for description of the hemodynamic changes that occur during OI. (Author)

  16. Groundwater recharge in desert playas: current rates and future effects of climate change

    Science.gov (United States)

    McKenna, Owen P.; Sala, Osvaldo E.

    2018-01-01

    Our results from playas, which are topographic low areas situated in closed-catchments in drylands, indicated that projected climate change in Southwestern USA would have a net positive impact over runon and groundwater recharge beneath playas. Expected increased precipitation variability can cause up to a 300% increase in annual groundwater recharge beneath playas. This increase will overshadow the effect of decreased precipitation amount that could cause up to a 50% decrease in recharge beneath playas. These changes could have a significant impact on groundwater and carbon storage. These results are important given that groundwater resources in Southwestern USA continue to decline due to human consumption outpacing natural recharge of aquifers. Here, we report on groundwater recharge rates ranging from less than 1 mm to greater than 25 mm per year beneath desert playas. Playas located in larger and steeper catchments with finer-textured soils had the highest rates of recharge. Vegetation cover had no effect on recharge beneath playas. We modeled catchment runoff generation and found that the amount of runon a playa receives annually strongly correlated to the rate of groundwater recharge beneath that playa. Runon occurred during precipitation events larger than 20 mm and increased linearly with events above that threshold.

  17. Cretaceous environmental changes led to high extinction rates in a hyperdiverse beetle family.

    Science.gov (United States)

    Kergoat, Gael J; Bouchard, Patrice; Clamens, Anne-Laure; Abbate, Jessica L; Jourdan, Hervé; Jabbour-Zahab, Roula; Genson, Gwenaelle; Soldati, Laurent; Condamine, Fabien L

    2014-10-21

    As attested by the fossil record, Cretaceous environmental changes have significantly impacted the diversification dynamics of several groups of organisms. A major biome turnover that occurred during this period was the rise of angiosperms starting ca. 125 million years ago. Though there is evidence that the latter promoted the diversification of phytophagous insects, the response of other insect groups to Cretaceous environmental changes is still largely unknown. To gain novel insights on this issue, we assess the diversification dynamics of a hyperdiverse family of detritivorous beetles (Tenebrionidae) using molecular dating and diversification analyses. Age estimates reveal an origin after the Triassic-Jurassic mass extinction (older than previously thought), followed by the diversification of major lineages during Pangaean and Gondwanan breakups. Dating analyses indicate that arid-adapted species diversified early, while most of the lineages that are adapted to more humid conditions diversified much later. Contrary to other insect groups, we found no support for a positive shift in diversification rates during the Cretaceous; instead there is evidence for an 8.5-fold increase in extinction rates that was not compensated by a joint increase in speciation rates. We hypothesize that this pattern is better explained by the concomitant reduction of arid environments starting in the mid-Cretaceous, which likely negatively impacted the diversification of arid-adapted species that were predominant at that time.

  18. Magnetoresistance in hybrid organic spin valves at the onset of multiple-step tunneling.

    Science.gov (United States)

    Schoonus, J J H M; Lumens, P G E; Wagemans, W; Kohlhepp, J T; Bobbert, P A; Swagten, H J M; Koopmans, B

    2009-10-02

    By combining experiments with simple model calculations, we obtain new insight in spin transport through hybrid, CoFeB/Al2O3(1.5 nm)/tris(8-hydroxyquinoline)aluminium (Alq3)/Co spin valves. We have measured the characteristic changes in the I-V behavior as well as the intrinsic loss of magnetoresistance at the onset of multiple-step tunneling. In the regime of multiple-step tunneling, under the condition of low hopping rates, spin precession in the presence of hyperfine coupling is conjectured to be the relevant source of spin relaxation. A quantitative analysis leads to the prediction of a symmetric magnetoresistance around zero magnetic field in addition to the hysteretic magnetoresistance curves, which are indeed observed in our experiments.

  19. Thermophilic archaeal community succession and function change associated with the leaching rate in bioleaching of chalcopyrite.

    Science.gov (United States)

    Zhu, Wei; Xia, Jin-lan; Yang, Yi; Nie, Zhen-yuan; Peng, An-an; Liu, Hong-chang; Qiu, Guan-zhou

    2013-04-01

    The community succession and function change of thermophilic archaea Acidianus brierleyi, Metallosphaera sedula, Acidianus manzaensis and Sulfolobus metallicus were studied by denaturing gradient gel electrophoresis (DGGE) analysis of amplifying 16S rRNA genes fragments and real-time qPCR analysis of amplifying sulfur-oxidizing soxB gene associated with chalcopyrite bioleaching rate at different temperatures and initial pH values. The analysis results of the community succession indicated that temperature and initial pH value had a significant effect on the consortium, and S. metallicus was most sensitive to the environmental change, A. brierleyi showed the best adaptability and sulfur oxidation ability and predominated in various leaching systems. Meanwhile, the leaching rate of chalcopyrite closely related to the consortium function embodied by soxB gene, which could prove a desirable way for revealing microbial sulfur oxidation difference and tracking the function change of the consortium, and for optimizing the leaching parameters and improving the recovery of valuable metals. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. Changes in ruminal volatile fatty acid production and absorption rate during the dry period and early lactation as affected by rate of increase of concentrate allowance

    NARCIS (Netherlands)

    Dieho, K.|info:eu-repo/dai/nl/314000550; Dijkstra, J.; Schonewille, J. T.|info:eu-repo/dai/nl/185364306; Bannink, A.

    The aim of the present experiment was to study changes in volatile fatty acid (VFA) production using an isotope dilution technique, and changes in VFA fractional absorption rate (k aVFA) using a buffer incubation technique (BIT) during the dry period and early lactation, as affected by the

  1. Seasonality of change: Summer warming rates do not fully represent effects of climate change on lake temperatures

    Science.gov (United States)

    Winslow, Luke; Read, Jordan S.; Hansen, Gretchen J. A.; Rose, Kevin C.; Robertson, Dale M.

    2017-01-01

    Responses in lake temperatures to climate warming have primarily been characterized using seasonal metrics of surface-water temperatures such as summertime or stratified period average temperatures. However, climate warming may not affect water temperatures equally across seasons or depths. We analyzed a long-term dataset (1981–2015) of biweekly water temperature data in six temperate lakes in Wisconsin, U.S.A. to understand (1) variability in monthly rates of surface- and deep-water warming, (2) how those rates compared to summertime average trends, and (3) if monthly heterogeneity in water temperature trends can be predicted by heterogeneity in air temperature trends. Monthly surface-water temperature warming rates varied across the open-water season, ranging from 0.013 in August to 0.073°C yr−1 in September (standard deviation [SD]: 0.025°C yr−1). Deep-water trends during summer varied less among months (SD: 0.006°C yr−1), but varied broadly among lakes (–0.056°C yr−1 to 0.035°C yr−1, SD: 0.034°C yr−1). Trends in monthly surface-water temperatures were well correlated with air temperature trends, suggesting monthly air temperature trends, for which data exist at broad scales, may be a proxy for seasonal patterns in surface-water temperature trends during the open water season in lakes similar to those studied here. Seasonally variable warming has broad implications for how ecological processes respond to climate change, because phenological events such as fish spawning and phytoplankton succession respond to specific, seasonal temperature cues.

  2. Examination of Changes in Infection Rates in a Restructured Anaesthesia Intensive Care Unit: A Retrospective Study.

    Science.gov (United States)

    Deniz, Ahmet; Erhan, Ömer Lütfi; Bayar, Mustafa Kemal; Karatepe, Ümit; Demirel, İsmail

    2017-12-01

    This retrospective study aimed to evaluate the effect of a restructured anaesthesia intensive care unit (ICU) on changes in infection rates and infections. Organisational restructuring was done in the anaesthesia ICU of Firat University Hospital after it was relocated on 14 March 2012. This study was designed to investigate the effect of restructuring on infection rates through a comparison of periods encompassing one year before relocation and one year after relocation. Nosocomial infections were diagnosed according to modified Centers for Disease Control and Prevention (CDC) criteria. In total, 406 patients who were over 18 years old and admitted to the ICU were included; they were hospitalised for 48 h or longer and had non-infectious diseases according to physical examination, laboratory and culture results on admission. The data of 214 patients (Group A) and 192 patients (Group B) were examined. Parameters such as age, gender, primary diagnosis and mean GCS score at admission and mean duration of hospitalisation showed no effect on the rates of infection, but rates of total infection (41.1% vs. 25%), urinary (18.7% vs. 10.4%) and VIP (32.7% vs. 14.6%) were detected in Groups A and B. Statistically significant differences were found for the causative pathogens Pseudomonas (15.4% vs. 6.8%), Acinetobacter (18.2% vs. 12%) and Escherichia (8.9% vs. 2.1%); the mean duration of mechanical ventilation (15.01±16.681 vs. 12.22±17.595) and discharge with improvement (31.8% vs. 44.3%). We detected that restructuring (such as acclimatization, educated staff, hepa filter) caused a significant decline in infection rates. Because ICU staff may be a major cause of infection, we believe that providing education and conducting effective surveillance programs will be the most important factors for reducing infection rates.

  3. Changes of Aldosterone Secretion Rate Following Furosemide Administration in Normotensive Subjects with High Sodium Intake

    International Nuclear Information System (INIS)

    Sung, Ho Kyung; Ryu, Yong Wun; Koh, Joo Hwan

    1976-01-01

    Marked augmentation of urinary aldosterone excretion following furosemide administration was observed in previous experiment. In this study, author measured the changes of aldosterone secretion after furosemide administration in normotensive young volunteers with high sodium intake. After intravenous injection of 1.2- 3 H-aldosterone, urine samples were collected in course of time until 24 hours after the injection. Furosemide administration was done at 30 minutes prior to aldosterone injection. Specific activities of 3H-aldosterone during and after diuresis were measured and aldosterone secretion rates were calculated dividing the doses by specific activities. Results were as followed. 1) Furosemide resulted in a marked increase in urinary aldosterone excretion. 2) Furosemide lead to an increase in both sodium and potassium excretion. 3) Aldosterone secretion rate was also increase d during furosemide diuresis, but the rate was smaller than that of urinary excretion. 4) Continuous modest increase in aldosterone secretion rate was shown after diuresis and total excess amount of aldosterone secretion for 24 hrs was equivalent to the amount of aldosterone excretion produced by diruesis. 5) Abrupt marked loss of circulating aldosterone produced by diuresis was supplemented by long lasting increase in secretion for over twenty four hours.

  4. Changing trends in hospitalization rates associated with psychosis: Spain, 1980-2009.

    Science.gov (United States)

    Medel-Herrero, Alvaro; Amate, J M; Saz-Parkinson, Z; Gómez-Beneyto, M

    2015-12-01

    To analyze the prevalence of hospitalization attributable to psychosis in Spain over the last three decades. Longitudinal analysis (1980-2009) of age-adjusted hospital discharges rates associated with psychosis (ICD9 290-8) in all Spanish hospitals. Spanish Hospital Morbidity Survey. The hospitalization rate associated with psychotic episodes had been gradually increasing since 1980 until 2004; an abrupt turnaround observed in 2004 marks the beginning of a steady decline in the rate. The turning point described is not observed for each of the psychotic diagnoses separately analyzed. However, it is clearly seen when data are grouped in diagnosis-related groups (organic-psychosis, functional psychosis and substance-induced psychosis) since the time course of the diseases within the major diagnostic groups are interrelated as evidenced by shared turning points which collectively display a common time course pattern. Main hospital indicators and antipsychotic drug prescriptions were analyzed for any possible turning point in mid-2000s. Psychiatric hospital beds and length of stays remained stable by 2004; the hospitalizations associated with non-psychotic psychiatric pathologies show no turning point in 2004. However, an abrupt change on antipsychotic drug prescriptions is precisely observed in 2004. After decades of linear growth, hospitalizations for psychotic patients begin to decline in 2004, coinciding with the start of last generation atypical antipsychotic drug consumption in Spain. Some of the psychotic diagnostic rates evolve in an interrelated manner which calls into question the diagnosis and nosological boundaries between some of these pathologies.

  5. Effects of imipramine of the orthostatic changes in blood pressure, heart rate and plasma catecholamines

    DEFF Research Database (Denmark)

    Nielsen, J R; Johansen, Torben; Arentoft, A

    1983-01-01

    The effect of imipramine on the orthostatic changes in heart rate, blood pressure and plasma catecholamines were examined in six healthy male subjects on two occasions on high sodium balance (Na+ excretion greater than 120 mmol per day) and on low sodium balance (Na+ excretion less than 110 mmol...... per day), respectively. Orthostatic tests were carried out before and 2 h after ingestion of 150 mg imipramine hydrochloride. Imipramine caused a moderate increase in supine systolic blood pressure, and a pronounced increase in the rise in heart rate, when the subjects assumed erect position....... The orthostatic drop in systolic blood pressure was in most cases only moderately increased after ingestion of imipramine, but in three subjects pronounced orthostatic hypotension developed when the sodium balance was low, whereas no clinical symptoms were seen in the same subjects when tested after imipramine...

  6. Radiocarbon dating, chronologic framework, and changes in accumulation rates of holocene estuarine sediments from Chesapeake Bay

    Science.gov (United States)

    Colman, Steven M.; Baucom, P.C.; Bratton, J.F.; Cronin, T. M.; McGeehin, J.P.; Willard, D.; Zimmerman, A.R.; Vogt, P.R.

    2002-01-01

    Rapidly accumulating Holocene sediments in estuaries commonly are difficult to sample and date. In Chesapeake Bay, we obtained sediment cores as much as 20 m in length and used numerous radiocarbon ages measured by accelarator mass spectrometry methods to provide the first detailed chronologies of Holocene sediment accumulation in the bay. Carbon in these sediments is a complex mixture of materials from a variety of sources. Analyses of different components of the sediments show that total organic carbon ages are largely unreliable, because much of the carbon (including coal) has been transported to the bay from upstream sources and is older than sediments in which it was deposited. Mollusk shells (clams, oysters) and foraminifera appear to give reliable results, although reworking and burrowing are potential problems. Analyses of museum specimens collected alive before atmospheric nuclear testing suggest that the standard reservoir correction for marine samples is appropriate for middle to lower Chesapeake Bay. The biogenic carbonate radiocarbon ages are compatible with 210 Pb and 137 Cs data and pollen stratigraphy from the same sites. Post-settlement changes in sediment transport and accumulation is an important environmental issue in many estuaries, including the Chesapeake. Our data show that large variations in sediment mass accumulation rates occur among sites. At shallow water sites, local factors seem to control changes in accumulation rates with time. Our two relatively deep-water sites in the axial channel of the bay have different long-term average accumulation rates, but the history of sediment accumulation at these sites appears to reflect overall conditions in the bay. Mass accumulation rates at the two deep-water sites rapidly increased by about fourfold coincident with widespread land clearance for agriculture in the Chesapeake watershed.

  7. Coherent electron-spin-resonance manipulation of three individual spins in a triple quantum dot

    Energy Technology Data Exchange (ETDEWEB)

    Noiri, A. [Department of Applied Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Yoneda, J.; Nakajima, T.; Otsuka, T.; Delbecq, M. R.; Takeda, K.; Tarucha, S. [Department of Applied Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); RIKEN, Center for Emergent Matter Science (CEMS), Wako-shi, Saitama 351-0198 (Japan); Amaha, S.; Allison, G. [RIKEN, Center for Emergent Matter Science (CEMS), Wako-shi, Saitama 351-0198 (Japan); Ludwig, A.; Wieck, A. D. [Lehrstuhl für Angewandte Festkörperphysik, Ruhr-Universität Bochum, D-44780 Bochum (Germany)

    2016-04-11

    Quantum dot arrays provide a promising platform for quantum information processing. For universal quantum simulation and computation, one central issue is to demonstrate the exhaustive controllability of quantum states. Here, we report the addressable manipulation of three single electron spins in a triple quantum dot using a technique combining electron-spin-resonance and a micro-magnet. The micro-magnet makes the local Zeeman field difference between neighboring spins much larger than the nuclear field fluctuation, which ensures the addressable driving of electron-spin-resonance by shifting the resonance condition for each spin. We observe distinct coherent Rabi oscillations for three spins in a semiconductor triple quantum dot with up to 25 MHz spin rotation frequencies. This individual manipulation over three spins enables us to arbitrarily change the magnetic spin quantum number of the three spin system, and thus to operate a triple-dot device as a three-qubit system in combination with the existing technique of exchange operations among three spins.

  8. Dynamics of spectral components of heart rate variability during changes in autonomic balance

    DEFF Research Database (Denmark)

    Højgaard, M V; Holstein-Rathlou, N H; Agner, E

    1998-01-01

    Frequency domain analysis of heart rate variability (HRV) has been proposed as a semiquantitative method for assessing activities in the autonomic nervous system. We examined whether absolute powers, normalized powers, and the low frequency-to-high frequency ratio (LF/HF) derived from the HRV power...... to contain the same information as powers expressed in normalized units. LF/HF detected the shift in autonomic balance induced by beta-blockade but not the change induced by supine position. In conclusion, none of the investigated measures derived from power spectral analysis comprehensively and consistently...

  9. Seasonal Variation in Monthly Average Air Change Rates Using Passive Tracer Gas Measurements

    DEFF Research Database (Denmark)

    Frederiksen, Marie; Bergsøe, Niels Christian; Kolarik, Barbara

    2011-01-01

    Indoor air quality in dwellings is largely determined by the air change rate (ACR) and the magnitude of indoor air pollution sources. Concurrently, great efforts are made to make buildings energy efficient, which may result in low ACRs. In the present study, the monthly ACR averages were measured...... than 30% of the overall average, were observed within the same dwellings, except during the warmest summer period, when ACR was generally higher. This suggests that a single measurement of the average ACR is a good indicator of the general situation, except for the summer period, and that varying...

  10. Polyphase Filter Banks for Embedded Sample Rate Changes in Digital Radio Front-Ends

    DEFF Research Database (Denmark)

    Awan, Mehmood-Ur-Rehman; Le Moullec, Yannick; Koch, Peter

    2011-01-01

    This paper presents efficient processing engines for software-defined radio (SDR) front-ends. These engines, based on a polyphase channelizer, perform arbitrary sample-rate changes, frequency selection, and bandwidth control. This paper presents an M-path polyphase filter bank based on a modified N....... A non-maximally-decimated polyphase filter bank (where the number of data loads is not equal to the number of M subfilters) processes M subfilters in a time period that is less than or greater than the M data loads. A polyphase filter bank with five different resampling modes is used as a case study...

  11. Evaluating the Impacts of Climate Change on Soil Erosion Rates in Central Mexico

    Directory of Open Access Journals (Sweden)

    Santos Martínez-Santiago

    2017-07-01

    Full Text Available Although water-eroded soil (WES resulting from human activities has been recognized as the leading global cause of land degradation, the soil erosion risks from climate change are not clear. Studies have reported that WES is the second most significant cause of soil loss in Mexico, and its future trajectory has not been sufficiently evaluated. The aims of this study are to 1 determine the impacts of climate change on WES and its distribution for the State of Aguascalientes, Mexico, and to 2 compare the present and future soil loss rates for the study unit (SU. The State of Aguascalientes is located in the “Region del Bajio.” The impact of climate change on WES was evaluated using the near-future divided world scenario (A2 presented in the IPCC Fourth Assessment Report. Daily temperature and precipitation data from 18 weather stations were downscaled to model historic laminar water erosion (HLWE and changes therein in the A2 near-future scenario for 2010–2039 (LWEScA2. Due to future changes in mean annual rainfall (MAR levels, a change in the LWEScA2 of between 1.6 and 8.9% could result in average soil losses up to 475.4 t ha-1 yr-1, representing a loss of slightly more than a 30-mm layer of mountain soil per year. The risk zones, classified as class 4 for LWE, are located to western of the State in part of municipalities of Calvillo, Jesus María, San José de Gracia y Cosio, where there are typical hills and falls with soil very sensitive to rain erosion.

  12. In vivo coordination structural changes of a potent insulin-mimetic agent, bis(picolinato)oxovanadium(IV), studied by electron spin-echo envelope modulation spectroscopy.

    Science.gov (United States)

    Fukui, K; Fujisawa, Y; OhyaNishiguchi, H; Kamada, H; Sakurai, H

    1999-01-01

    Bis(picolinato)oxovanadium(IV) [VO(pic)2] is one of the most potent insulin-mimetic vanadium complexes. To probe coordination structural changes of this complex in vivo and provide insights into the origin of its high potency, an electron spin-echo envelope modulation (ESEEM) study was performed on organs (kidney, liver and bone) of VO(pic)2- and VOSO4-treated rats. Kidney and liver samples from both types of rats exhibited a 14N ESEEM signal that could be attributed to equatorially coordinating amine nitrogen. The relative intensity of the amine signal was larger for the organs of the rat treated with the less potent VOSO4, suggesting that this amine coordination inhibits the insulin-mimetic activity. The spectra of kidney and liver from the VO(pic)2-treated rat contained a weak signal due to the picolinate imine nitrogen. This suggests that some picolinato species (including both the bispicolinato and a partially decomposed monopicolinato species) still exist in the organs as a minor species, where the proportions of the picolinato species to the total amount of the EPR-detectable VIVO species are estimated as 8-16% in the kidney and 12-24% in the liver. The picolinate ligand presumably serves to prevent VO2+ from being converted into the inactive amine-coordinated species. Bone samples from both types of rats exhibited an ESEEM signal due to 31P nuclei. The VO2+ in bone is therefore most likely incorporated into the hydroxyapatite Ca10(PO4)6(OH)2 matrix, which is consistent with the hypothesis that the bone-accumulated VO2+ is gradually released and transported to other organs as is Ca2+. No 14N signals were observed, even in the bone samples of the VO(pic)2-treated rats, indicating that vanadium uptake by bone requires complete decomposition of the complex.

  13. Nuclear spin-lattice relaxation in nitroxide spin-label EPR

    DEFF Research Database (Denmark)

    Marsh, Derek

    2016-01-01

    that the definition of nitrogen nuclear relaxation rate Wn commonly used in the CW-EPR literature for 14N-nitroxyl spin labels is inconsistent with that currently adopted in time-resolved EPR measurements of saturation recovery. Redefinition of the normalised 14N spin-lattice relaxation rate, b = Wn/(2We), preserves...... of spin-lattice relaxation in this three-level system. Expressions for CW-saturation EPR with the revised definitions are summarised. Data on nitrogen nuclear spin-lattice relaxation times are compiled according to the three-level scheme for 14N-relaxation: T1 n = 1/Wn. Results are compared and contrasted...... the expressions used for CW-EPR, whilst rendering them consistent with expressions for saturation recovery rates in pulsed EPR. Furthermore, values routinely quoted for nuclear relaxation times that are deduced from EPR spectral diffusion rates in 14N-nitroxyl spin labels do not accord with conventional analysis...

  14. Detailed mechanisms of1H spin-lattice relaxation in ammonium dihydrogen phosphate confirmed by magic angle spinning.

    Science.gov (United States)

    Hayashi, Shigenobu; Jimura, Keiko

    2017-10-01

    Mechanisms of the 1 H spin-lattice relaxation in NH 4 H 2 PO 4 were studied in detail by use of the effect of magic angle spinning on the relaxation. The acid and the ammonium protons have different relaxation times at the spinning rates higher than 10 kHz due to suppression of spin diffusion between the two kinds of protons. The intrinsic relaxation times not affected by the spin diffusion and the spin-diffusion assisted relaxation times were evaluated separately, taking into consideration temperature dependence. Both mechanisms contribute to the 1 H relaxation of the acid protons comparatively. The spin-diffusion assisted relaxation mechanism was suppressed to the level lower than the experimental errors at the spinning rate of 30 kHz. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. The spin lattice relaxation of {sup 8}Li in simple metals

    Energy Technology Data Exchange (ETDEWEB)

    Hossain, M.D.; Saadaoui, H. [Department of Physics, University of British Columbia, Vancouver, BC, V6T 1Z1 (Canada); Parolin, T.J. [Chemistry Department, University of British Columbia, Vancouver, BC, V6T 1Z1 (Canada); Song, Q.; Wang, D.; Smadella, M. [Department of Physics, University of British Columbia, Vancouver, BC, V6T 1Z1 (Canada); Chow, K.H.; Egilmez, M.; Fan, I. [Department of Physics, University of Alberta, Edmonton, AB, T6G 2G7 (Canada); Kiefl, R.F. [Department of Physics, University of British Columbia, Vancouver, BC, V6T 1Z1 (Canada); Canadian Institute of Advanced Research (Canada); Kreitzman, S.R.; Levy, C.D.P.; Morris, G.D.; Pearson, M.R. [TRIUMF, 4004 Wesbrook Mall, Vancouver, BC, V6T 2A3 (Canada); Salman, Z. [TRIUMF, 4004 Wesbrook Mall, Vancouver, BC, V6T 2A3 (Canada); Clarendon Laboratory, Department of Physics, Oxford University, Parks Road, Oxford OX1 3PU (United Kingdom); MacFarlane, W.A., E-mail: wam@chem.ubc.c [Chemistry Department, University of British Columbia, Vancouver, BC, V6T 1Z1 (Canada)

    2009-04-15

    We report the modification to the linear temperature dependence of the Korringa nuclear spin-lattice relaxation rate of an implanted NMR probe in silver, as it makes a thermally activated site change. We develop a simple model of this phenomenon, which is found in a number of metals including Au and Nb.

  16. Changes in salivary flow rates in head and neck cancer after chemoradiotherapy

    Directory of Open Access Journals (Sweden)

    Lal Punita

    2010-01-01

    Full Text Available Background: Changes in salivary flow rate were studied in head and neck (H and N cancer patients who, after receiving moderately accelerated radiotherapy (RT and concurrent chemotherapy (CT, were free of disease at 1 year. Materials and Methods: Between July 2003 and July 2005, saliva estimation was performed for 36 patients of locally advanced (AJCC stages III and IV squamous cell carcinoma of the H and N. RT, moderately accelerated (70Gy/35 fx/6 weeks along with concurrent weekly cisplatin at 35 mg/m 2 (capped at 50 mg with standard hydration and anti-emetic cover, was planned using conventional planning on telecobalt or 6 MV photons. The saliva flow rate was estimated for 5 min at rest (unstimulated and after using lemon drops (stimulated for the next 5 min at baseline (pre-treatment, 3, 6 and 12 months following treatment. Results: The median follow-up of this study was 29 months. Compared with baseline, by 3 months, a significant reduction in unstimulated (0.35 ml/min and 0.10 ml/min and stimulated (0.97 ml/min and 0.28 ml/min salivary flow rate was observed, respectively. This continued to decrease further till 6 months (0.06 ml/min and 0.17 ml/min and, by 12 months, a minimal and non-significant recovery was observed in both unstimulated (0.08 ml/min and stimulated salivary flow rates (0.22 ml/min, respectively. Conclusions: Salivary flow rates fall to a fourth of the baseline value with the above CT + RT protocol, with minimal recovery at 12 months following completion of treatment.

  17. Changing Survival Rate of Infants Born Before 26 Gestational Weeks; Single-centre study

    Directory of Open Access Journals (Sweden)

    Asad Rahman

    2015-08-01

    Full Text Available Objectives: This study aimed to evaluate the changing survival rate and morbidities among infants born before 26 gestational weeks at the Sultan Qaboos University Hospital (SQUH in Muscat, Oman. Methods: This retrospective study assessed the mortality and morbidities of all premature infants born alive at 23–26 gestational weeks at SQUH between June 2006 and May 2013. Infants referred to SQUH within 72 hours of birth during this period were also included. Electronic records were reviewed for gestational age, gender, birth weight, maternal age, mode and place of delivery, antenatal steroid administration, morbidity and outcome. The survival rate was calculated and findings were then compared with those of a previous study conducted in the same hospital from 1991 to 1998. Rates of major morbidities were also calculated. Results: A total of 81 infants between 23–26 gestational weeks were admitted to the neonatal unit during the study period. Of these, 58.0% were male and 42.0% were female. Median gestational age was 25 weeks and mean birth weight was 770 ± 150 g. Of the 81 infants, 49 survived. The overall survival rate was 60.5% compared to 41% reported in the previous study. Respiratory distress syndrome (100.0%, retinopathy of prematurity (51.9%, bronchopulmonary dysplasia (34.6%, intraventricular haemorrhage (30.9% and patent ductus arteriosus (28.4% were the most common morbidities. Conclusion: The overall survival rate of infants between 23–26 gestational weeks during the study period had significantly improved in comparison to that found at the same hospital from 1991 to 1998. There is a need for the long-term neurodevelopmental follow-up of premature infants.

  18. Modulation of erosion rates of uplifting landscapes by long-term climate change: Experimental investigation

    Science.gov (United States)

    Moussirou, Bérangé; Bonnet, Stéphane

    2017-04-01

    Whether climatic variations play a major role, or not, in setting the erosion rate of continental landscapes is key for demonstrating the influence of climate on the tectonic evolution of mountain belts, as expected from analytical, numerical and analog modelling approaches. These models actually demonstrate that any modification in surface erosion rate that would affect significantly the gravitational loading of the continental crust might change its state of stress and consequently its deformation. However field evidences of these interactions has proved challenging to demonstrate unambiguously, the question of the climatic control on erosion efficiency at the geological time-scale being among the most critical issues. Here, we investigate how a change in precipitation influences the erosional dynamics of a landscape on the basis of an experimental approach where we surveyed the erosion by runoff of water of laboratory-scale landscapes that evolved under the combination of uplift and rainfall forcings (e.g. Bonnet and Crave, 2006). The experimental facility used is a modified of a device initially developed in the Geosciences Rennes laboratory and now set up in the Geosciences Environnement Toulouse laboratory. Following early experiments of Bonnet and Crave (2003) where the effect of a sudden drop in precipitation was investigated, we consider here the impact of decreasing rainfall events of finite duration on the erosive response of a landscape forced by a constant uplift (10 mm/h) and initially at steady-state (SS1). We performed several experiments with the same amplitude (from 160 to 60mm/h) but with different duration of rainfall drop (Tp: 0, 60, 300, 500, 700 min). As predicted theoretically and already observed in numerical and experimental modelling studies, a sudden drop of precipitation rate (Tp=0) induced a decrease of the mean erosion rate of the landscape (E), resulting in surface uplift. Then, landscape mean elevation stabilized to a higher value

  19. Spin-Mechatronics

    Science.gov (United States)

    Matsuo, Mamoru; Saitoh, Eiji; Maekawa, Sadamichi

    2017-01-01

    We investigate the interconversion phenomena between spin and mechanical angular momentum in moving objects. In particular, the recent results on spin manipulation and spin-current generation by mechanical motion are examined. In accelerating systems, spin-dependent gauge fields emerge, which enable the conversion from mechanical angular momentum into spins. Such a spin-mechanical effect is predicted by quantum theory in a non-inertial frame. Experiments which confirm the effect, i.e., the resonance frequency shift in nuclear magnetic resonance, the stray field measurement of rotating metals, and electric voltage generation in liquid metals, are discussed.

  20. A 50-ky record of climate, ecosystem, and erosion rate change in the Oregon Coast Range

    Science.gov (United States)

    Marshall, J. A.; Roering, J. J.; Granger, D. E.; Gavin, D. G.

    2013-12-01

    In unglaciated landscapes, quantifying landscape response to millennial-scale climate fluctuations is often restricted to temporally and spatially limited archives such as terrace deposits. In addition, mechanistic explanations for landscape response to climate change are lacking. Specifically it is unclear how climate controls the vigor and rate of soil production and transport, as processes in modern ecosystems (e.g. bioturbation such as tree throw) tend to bias our interpretations of landscape evolution. Here, we present results coupling a 50-ky paleo-environmental record with cosmogenic 10Be-derived paleo-erosion rates spanning non-glacial, glacial, and inter-glacial intervals from a 63m sediment archive in the Oregon Coast Range (OCR). At Little Lake, our landslide-dammed lake study site, we refined previous records of paleo-climate to better constrain paleo-temperature and thus the likelihood of frost-driven vs. biotic erosional processes prior to the Holocene. The presence of Picea sitchensis (Sitka spruce) and Abies lasiocarpa (subalpine fir) in the core during the Last Glacial Maximum (LGM) imply mean annual temperatures of ~ 1 °C and January mean temperatures of ~ -7 °C. This contrasts sharply with modern temperatures of 11 °C and 5 °C respectively. Using 14C (n=21) and OSL (n=3), we constructed a chronology for our sediment archives that spans the non-glacial (50-26 ka) and glacial intervals (26- 16 ka) and the late Holocene (3 ka to present). Our depth-age model shows that sediment accumulation rates increased 5x from the non-glacial to the glacial interval, coincident with a transition from finely laminated clays and sands to coarse blue-grey sands. We extracted 25 samples for 10Be analysis from the core over an average interval of 1500 years. Preliminary 10Be-derived erosion rates show increasing erosion rates from 0.06 × 0.02 mm/yr (48 ka) to 0.18 × 0.02 mm/yr (28 ka) during the non-glacial interval as temperatures cooled and the forest

  1. Disordered kagomé spin ice

    Science.gov (United States)

    Greenberg, Noah; Kunz, Andrew

    2018-05-01

    Artificial spin ice is made from a large array of patterned magnetic nanoislands designed to mimic naturally occurring spin ice materials. The geometrical arrangement of the kagomé lattice guarantees a frustrated arrangement of the islands' magnetic moments at each vertex where the three magnetic nanoislands meet. This frustration leads to a highly degenerate ground state which gives rise to a finite (residual) entropy at zero temperature. In this work we use the Monte Carlo simulation to explore the effects of disorder in kagomé spin ice. Disorder is introduced to the system by randomly removing a known percentage of magnetic islands from the lattice. The behavior of the spin ice changes as the disorder increases; evident by changes to the shape and locations of the peaks in heat capacity and the residual entropy. The results are consistent with observations made in diluted physical spin ice materials.

  2. Distinct global warming rates tied to multiple ocean surface temperature changes

    Science.gov (United States)

    Yao, Shuai-Lei; Luo, Jing-Jia; Huang, Gang; Wang, Pengfei

    2017-07-01

    The globally averaged surface temperature has shown distinct multi-decadal fluctuations since 1900, characterized by two weak slowdowns in the mid-twentieth century and early twenty-first century and two strong accelerations in the early and late twentieth century. While the recent global warming (GW) hiatus has been particularly ascribed to the eastern Pacific cooling, causes of the cooling in the mid-twentieth century and distinct intensity differences between the slowdowns and accelerations remain unclear. Here, our model experiments with multiple ocean sea surface temperature (SST) forcing reveal that, although the Pacific SSTs play essential roles in the GW rates, SST changes in other basins also exert vital influences. The mid-twentieth-century cooling results from the SST cooling in the tropical Pacific and Atlantic, which is partly offset by the Southern Ocean warming. During the recent hiatus, the tropical Pacific-induced strong cooling is largely compensated by warming effects of other oceans. In contrast, during the acceleration periods, ubiquitous SST warming across all the oceans acts jointly to exaggerate the GW. Multi-model simulations with separated radiative forcing suggest diverse causes of the SST changes in multiple oceans during the GW acceleration and slowdown periods. Our results highlight the importance of multiple oceans on the multi-decadal GW rates.

  3. God-Mediated Control and Change in Self-Rated Health.

    Science.gov (United States)

    Krause, Neal

    2010-10-01

    The purpose of this study was to see if feelings of God-mediated control are associated with change in self-rated health over time. In the process, an effort was made to see if a sense of meaning in life and optimism mediated the relationship between God-mediated control and change in health. The following hypothesized relationships were contained in the conceptual model that was developed to evaluate these issues: (1) people who go to church more often tend to have stronger God-mediated control beliefs than individuals who do not attend worship services as often; (2) people with a strong sense of God-mediated control are more likely to find a sense of meaning in life and be more optimistic than individuals who do not have a strong sense of God-mediated control; (3) people who are optimistic and who have a strong sense of meaning in life will rate their health more favorably over time than individuals who are not optimistic, as well as individuals who have not found a sense of meaning in life. Data from a longitudinal nationwide survey of older adults provided support for each of these hypotheses.

  4. The Impact of Changes to the Unemployment Rate on Australian Disability Income Insurance Claim Incidence

    Directory of Open Access Journals (Sweden)

    Gaurav Khemka

    2017-03-01

    Full Text Available We explore the extent to which claim incidence in Disability Income Insurance (DII is affected by changes in the unemployment rate in Australia. Using data from 1986 to 2001, we fit a hurdle model to explore the presence and magnitude of the effect of changes in unemployment rate on the incidence of DII claims, controlling for policy holder characteristics and seasonality. We find a clear positive association between unemployment and claim incidence, and we explore this further by gender, age, deferment period, and occupation. A multinomial logistic regression model is fitted to cause of claim data in order to explore the relationship further, and it is shown that the proportion of claims due to accident increases markedly with rising unemployment. The results suggest that during periods of rising unemployment, insurers may face increased claims from policy holders with shorter deferment periods for white-collar workers and for medium and heavy manual workers. Our findings indicate that moral hazard may have a material impact on DII claim incidence and insurer business in periods of declining economic conditions.

  5. Increased rate of acceleration on Pine Island Glacier strongly coupled to changes in gravitational driving stress

    Directory of Open Access Journals (Sweden)

    J. B. T. Scott

    2009-05-01

    Full Text Available Pine Island Glacier, Antarctica, has been undergoing several related changes for at least two decades; these include acceleration, thinning and grounding line retreat. During the first major ground-based study between 2006 and 2008, GPS receivers were used to monitor ice flow from 55 km to 171 km inland, along the central flowline. At four sites both acceleration and thinning rates over the last two years exceeded rates observed at any other time over the last two decades. At the downstream site acceleration was 6.4% over 2007 and thinning was 3.5±0.5 ma−1. Acceleration and thinning have spread rapidly inland with the acceleration 171 km inland at 4.1% over 2007, greater than any measured annual flow increase along the whole glacier prior to 2006. Increases in surface slope, and hence gravitational driving stress, correlate well with the acceleration and no sustained change in longitudinal stress gradient is needed to explain the force balance. There is no indication that the glacier is approaching a new steady state.

  6. Do physiological and pathological stresses produce different changes in heart rate variability?

    Directory of Open Access Journals (Sweden)

    Andrea eBravi

    2013-07-01

    Full Text Available Although physiological (e.g. exercise and pathological (e.g. infection stress affecting the cardiovascular system have both been documented to be associated with a reduction in overall heart rate variability (HRV, it remains unclear if loss of HRV is ubiquitously similar across different domains of variability analysis or if distinct patterns of altered HRV exist depending on the stressor. Using Continuous Individualized Multiorgan Variability Analysis (CIMVATM software, heart rate (HR and four selected measures of variability were measured over time (windowed analysis from two datasets, a set (n=13 of patients who developed systemic infection (i.e. sepsis after bone marrow transplant, and a matched set of healthy subjects undergoing physical exercise under controlled conditions. HR and the four HRV measures showed similar trends in both sepsis and exercise. The comparison through Wilcoxon sign-rank test of the levels of variability at baseline and during the stress (i.e. exercise or after days of sepsis development showed similar changes, except for LF/HF, ratio of power at low and high frequencies (associated with sympathovagal modulation, which was affected by exercise but did not show any change during sepsis. Furthermore, HRV measures during sepsis showed a lower level of correlation with each other, as compared to HRV during exercise. In conclusion, this exploratory study highlights similar responses during both exercise and infection, with differences in terms of correlation and inter-subject fluctuations, whose physiologic significance merits further investigation.

  7. Time changes of vertical profile of neutron fluence rate in LVR-15 reactor

    International Nuclear Information System (INIS)

    Viererbl, L.; Stehno, J.; Erben, O.; Lahodova, Z.; Marek, M.

    2003-01-01

    The LVR-15 reactor is a light water research type reactor, which is situated, in Nuclear Research Institute, Rez near Prague. The reactor is used as a multipurpose facility. For some experiments and material productions, e.g. for homogeneity of silicon resistance in production of radiation doped silicon, the time changes of vertical profile of neutron fluence rate are particularly important. The assembly used for silicon irradiation has two self-powered neutron detectors installed in a vertical irradiation channel in LVR-15 reactor. Vertical profile of thermal neutron fluence rate was automatically scanned during reactor operation. The results of measurements made in 2002 and 2003 with these detectors are presented. A set of vertical profile measurements was made during two 21-days reactor cycles. During the cycle the vertical profile slightly changes both in the position of its maximum and in the shape. The time dependences of the position of profile maximum and the profile width at half maximum during the cycle are given. (author)

  8. Use of spin labels and electron spin resonance spectroscopy to characterize membranes of bovine sperm: effect of butylated hydroxytoluene and cold shock

    Energy Technology Data Exchange (ETDEWEB)

    Hammerstedt, R.H.; Amann, R.P.; Rucinsky, T.; Morse, P.D. II; Lepock, J.; Snipes, W.; Keith, A.D.

    1976-05-01

    Spin label probes were used in conjunction with measurements of metabolic rate and electron microscopy to characterize bovine sperm membranes. Aqueous compartments, membrane hydrocarbon zones and lipid : water interfaces were studied separately using appropriate spin labels. For sperm suspended in aqueous medium, the cold shock associated with rapid cooling from room temperature to 0/sup 0/ increased membrane permeability. This membrane damage was readily detected using spin labels but was not detected using thin section electron microscopy. This change was prevented by the addition of butylated hydroxy toluene (BHT). BHT provided partial protection against further damage caused by freezing sperm on solid CO/sub 2/. ESR techniques provide a rapid means to quantify the changes in sperm membranes occurring during the epididymal maturation of sperm and subsequent events within the female tract leading to fertilization. The technique also could be used to assess damage to sperm, ova or embryos during preparation for storage in cryoprotective diluents.

  9. Evaluation of layback spin in figure skating

    Directory of Open Access Journals (Sweden)

    Jastšenjski Ksenija

    2011-01-01

    Full Text Available Layback spin is considered as one of the most beautiful and elegant spins performed in figure skating. It is also one of the required spins in competitive short program in female category. Different techniques of executing layback spin with variations in changing the positions of free parts of the body, as well as the evaluation of layback spin in accordance with ISU rules and regulations, which have been used in all International Skating Federation competitions since 2004 (World and European championships, Olympic Games are presented in this paper. Due to very difficult position of the body while performing a layback spin, it is essential that the skaters who want to master it should have excellent agility (especially of the spinal column and shoulder and knee joints and balance. Layback spin performance requires significant skating knowledge, so it cannot be performed by beginners. Depending on the fl exibility and creativity, a skater can execute various positions of the head, arms, body and free leg while performing a layback spin. In some cases, these variations can increase the level of difficulty, and in others only the mark given for executing this spin.

  10. Effect of spin-orbit scattering on transport properties of low-dimensional dilute alloys

    Energy Technology Data Exchange (ETDEWEB)

    Heers, Swantje

    2011-09-21

    The scope of this thesis is to gain insight, by means of ab initio-calculations, into the physics of momentum and spin relaxation phenomena induced by electron scattering at impurities and defects in the noble metals copper, silver and gold. The main results are subdivided in three parts. In the first part, momentum- and spinrelaxation times due to scattering at 3d, 4sp, 4d, 5sp, 5d and 6sp impurities in copper and gold fcc bulk are investigated. The inversion symmetry of the crystals leads to a two-fold degeneracy of all states on the Fermi surface, and therefore spin relaxation is dominated by the Elliott-Yafet mechanism as well as the spin-orbit coupling of the impurity. For impurities in gold, we calculate much shorter spin-relaxation times than in copper because of the stronger spin-orbit coupling of the gold host. Furthermore, we have found important qualitative differences between the relaxation times obtained for the d- and the sp- impurities. As scattering at d-impurities is resonant, the electrons spend much more time at the impurity sites than in the case of the sp-impurities; therefore, they are much longer exhibited to the spin-orbit coupling of the impurity. This results in considerably shorter spin-relaxation times, even if the momentum scattering rates are in the same order of magnitude. Finally, the investigation of interference of scattering processes at impurity dimers reveals that relevant differences to the independent-impurity approximation appear only for strong d-scatterer, placed at nearest neighboring sites. In the second part we investigate the reduction of spin-conserving surface-state lifetimes induced by adatom- and impurity-scattering on the (111) surfaces of copper, silver and gold films with different thicknesses. We have found strong qualitative differences in the lifetimes when comparing the results for adatoms to those of impurities in the first and second layer. The trends for the latter ones are similar to those calculated in

  11. Decrease in Suicide Rates after a Change of Policy Reducing Access to Firearms in Adolescents: A Naturalistic Epidemiological Study

    Science.gov (United States)

    Lubin, Gad; Werbeloff, Nomi; Halperin, Demian; Shmushkevitch, Mordechai; Weiser, Mark; Knobler, Haim Y.

    2010-01-01

    The use of firearms is a common means of suicide. We examined the effect of a policy change in the Israeli Defense Forces reducing adolescents' access to firearms on rates of suicide. Following the policy change, suicide rates decreased significantly by 40%. Most of this decrease was due to decrease in suicide using firearms over the weekend.…

  12. Two-dimensional spin diffusion in multiterminal lateral spin valves

    Science.gov (United States)

    Saha, D.; Basu, D.; Holub, M.; Bhattacharya, P.

    2008-01-01

    The effects of two-dimensional spin diffusion on spin extraction in lateral semiconductor spin valves have been investigated experimentally and theoretically. A ferromagnetic collector terminal of variable size is placed between the ferromagnetic electron spin injector and detector of a conventional lateral spin valve for spin extraction. It is observed that transverse spin diffusion beneath the collector terminal plays an important role along with the conventional longitudinal spin diffusion in describing the overall transport of spin carriers. Two-dimensional spin diffusion reduces the perturbation of the channel electrochemical potentials and improves spin extraction.

  13. Changes in heart-rate variability of survivors of nasopharyngeal cancer during Tai Chi Qigong practice.

    Science.gov (United States)

    Fong, Shirley S M; Wong, Janet Y H; Chung, Louisa M Y; Yam, Timothy T T; Chung, Joanne W Y; Lee, Y M; Chow, Lina P Y; Luk, W S; Ng, Shamay S M

    2015-05-01

    [Purpose] To explore the changes in heart-rate variability (HRV) of survivors of nasopharyngeal cancer (NPC) before, during, and after a Tai Chi (TC) Qigong exercise. [Subjects and Methods] Eleven survivors of NPC participated voluntarily in the study. The heart rate of each participant was measured continuously for 1 minute before the TC Qigong intervention, during the 5-minute TC Qigong intervention, and for 1 minute after the intervention, using a Polar heart-rate monitor. Spectral HRV was expressed in terms of normalised low frequency (LF) power, normalised high frequency (HF) power, and the low frequency/high frequency (LF/HF) power ratio. [Results] Both the LF-power and the HF-power components had significant time effects. However, the time effect of the LF/HF power ratio was not significant. Post hoc contrast analysis revealed a significant decrease in LF power and a concomitant increase in HF power during the 4th minute and 5th minute of the TC Qigong exercise. [Conclusion] Five minutes of TC Qigong exercise was found to improve HRV by increasing HF power and decreasing LF power, but these effects were transient. TC Qigong might be an appropriate exercise for improving the ANS function and psychological and cardiac health of survivors of NPC.

  14. DIVIDEND PAYMENT BEHAVIOUR OF COMPANIES DUE TO CHANGE OF DIVIDEND TAX RATE IN ROMANIA

    Directory of Open Access Journals (Sweden)

    Stela JAKOVA

    2017-06-01

    Full Text Available This paper examines Romanian companies’ behaviour (listed on the Bucharest Stock Exchange to a change of dividend tax rate. Even if the number of companies which had paid dividends in 2016, for 2015 decreased to 32, compared with 34 companies from previous year, the total value of paid dividends increased with 53% comparatively with dividends paid for 2014. This can be explained through the new tax rate which has been reduced from 16% to 5%. We found that the shareholders obtain profit from two sources: due to increase of gross dividend and due to decrease of the tax rate. Moreover, the paper found also: for the companies who paid higher dividend for 2015 compared with 2014 the dividend paid for 2015 is statistically significant different than the dividend paid for 2014; for the companies who paid smallest dividend for 2015, we were not able to find any statistical difference. This means that the companies which increased the dividend for 2015, took into consideration the new legislation and they are motivated to pay more to the shareholders; companies which decreased the dividend value for 2015 is due to some internal factors.

  15. Timing and Variability of Galactose Metabolic Gene Activation Depend on the Rate of Environmental Change.

    Science.gov (United States)

    Nguyen-Huu, Truong D; Gupta, Chinmaya; Ma, Bo; Ott, William; Josić, Krešimir; Bennett, Matthew R

    2015-07-01

    Modulation of gene network activity allows cells to respond to changes in environmental conditions. For example, the galactose utilization network in Saccharomyces cerevisiae is activated by the presence of galactose but repressed by glucose. If both sugars are present, the yeast will first metabolize glucose, depleting it from the extracellular environment. Upon depletion of glucose, the genes encoding galactose metabolic proteins will activate. Here, we show that the rate at which glucose levels are depleted determines the timing and variability of galactose gene activation. Paradoxically, we find that Gal1p, an enzyme needed for galactose metabolism, accumulates more quickly if glucose is depleted slowly rather than taken away quickly. Furthermore, the variability of induction times in individual cells depends non-monotonically on the rate of glucose depletion and exhibits a minimum at intermediate depletion rates. Our mathematical modeling suggests that the dynamics of the metabolic transition from glucose to galactose are responsible for the variability in galactose gene activation. These findings demonstrate that environmental dynamics can determine the phenotypic outcome at both the single-cell and population levels.

  16. Three dimensional evaluation of alveolar bone changes in response to different rapid palatal expansion activation rates

    Directory of Open Access Journals (Sweden)

    Brian LaBlonde

    Full Text Available ABSTRACT Introduction: The aim of this multi-center retrospective study was to quantify the changes in alveolar bone height and thickness after using two different rapid palatal expansion (RPE activation protocols, and to determine whether a more rapid rate of expansion is likely to cause more adverse effects, such as alveolar tipping, dental tipping, fenestration and dehiscence of anchorage teeth. Methods: The sample consisted of pre- and post-expansion records from 40 subjects (age 8-15 years who underwent RPE using a 4-banded Hyrax appliance as part of their orthodontic treatment to correct posterior buccal crossbites. Subjects were divided into two groups according to their RPE activation rates (0.5 mm/day and 0.8 mm/day; n = 20 each group. Three-dimensional images for all included subjects were evaluated using Dolphin Imaging Software 11.7 Premium. Maxillary base width, buccal and palatal cortical bone thickness, alveolar bone height, and root angulation and length were measured. Significance of the changes in the measurements was evaluated using Wilcoxon signed-rank test and comparisons between groups were done using ANOVA. Significance was defined at p ≤ 0.05. Results: RPE activation rates of 0.5 mm per day (Group 1 and 0.8 mm per day (Group 2 caused significant increase in arch width following treatment; however, Group 2 showed greater increases compared to Group 1 (p < 0.01. Buccal alveolar height and width decreased significantly in both groups. Both treatment protocols resulted in significant increases in buccal-lingual angulation of teeth; however, Group 2 showed greater increases compared to Group 1 (p < 0.01. Conclusion: Both activation rates are associated with significant increase in intra-arch widths. However, 0.8 mm/day resulted in greater increases. The 0.8 mm/day activation rate also resulted in more increased dental tipping and decreased buccal alveolar bone thickness over 0.5 mm/day.

  17. Patterned changes in urge ratings with tic suppression in youth with chronic tic disorders.

    Science.gov (United States)

    Brabson, Laurel A; Brown, Jessica L; Capriotti, Matthew R; Ramanujam, Krishnapriya; Himle, Michael B; Nicotra, Cassandra M; Ostrander, Rick; Kelly, Laura M; Grados, Marco A; Walkup, John T; Perry-Parrish, Carisa; Reynolds, Elizabeth K; Hankinson, Jessica C; Specht, Matt W

    2016-03-01

    Premonitory urges are central to emerging behavioral models of chronic tic disorders (CTD). Urge reduction has been proposed as a behavioral explanation for tic maintenance and exacerbation as well as the efficacy of behavioral treatments. Prior investigations have produced inconsistent findings despite common methodologies. The current study evaluated the possibility that data aggregation obscures distinct and meaningful patterns of change in urge ratings when tics are freely expressed versus suppressed. Participants (n = 12) included children with moderate-to-marked tic severity and noticeable premonitory urges. Tic frequencies and urge ratings were obtained at 15 s and 10-s intervals, respectively, across an alternating sequence of 10-min tic freely and 40-min tic suppression conditions. Patterns were established using a two step approach. Five distinct patterns of urge rating change emerged, suggesting data aggregation may obscure meaningful patterns in the urge-tic relationship when tics are completed versus suppressed. Eligibility criteria may have unintentionally excluded younger affected children and included older participants with more severe tic disorders than commonly seen. Additional research with less stringent eligibility criteria and a larger sample size will help validate the results. The relationship between urges and tics is much more complex than previously theorized. Investigations that rely on global assessments of urge and tic severity and/or assume uniformity when aggregating participant data may obscure meaningful differences in the urge-tic relationship. Future investigations should examine the possibility that individual differences and/or developmental considerations modulate the functional urge-tic relationship. Copyright © 2015. Published by Elsevier Ltd.

  18. Spin Orbit Torque in Ferromagnetic Semiconductors

    KAUST Repository

    Li, Hang

    2016-06-21

    effect on spin orbit torque in nanoribbons with a hexagonal lattice. We find a dramatic modification of the nature of the torque (field like and damping-like component) when crossing the topological phase transition. The relative agnitude of the two torque components can be significantly modifies by changing the magnetization direction. Finally, motivated by recent experimental results, we conclude by investigating the features of spin-orbit torque in magnetic transition metal dichalcogenides. We find the torque is associated with the valley polarization. By changing the magnetization direction, the torque can be changed from a finite value to zero when the valley polarization decreases from a finite value to zero.

  19. Cesarean section rate in Iran, multidimensional approaches for behavioral change of providers: a qualitative study

    Directory of Open Access Journals (Sweden)

    Rashidian Arash

    2011-07-01

    Full Text Available Abstract Background The cesarean section rate has been steadily rising from 35% in 2000 to 40% in 2005 in Iran. The objective of this study was to identify barriers of reduce the cesarean section rate in Iran, as perceived by obstetricians and midwives as the main behavioral change target groups. Methods A qualitative study with purposive sampling was designed in which data were collected through in-depth interviews and document analyses. Hospitals were selected on the bases of being public and or private and their response to the ministry's C-section reduction interventions. The hospital director, obstetricians and midwives from each hospital were included in the study. The classification of barriers suggested by Grol and Wensing was used for the thematic analysis. Results After 26 in-depth interviews and document analyses, the barriers were identified as: financial, insurance and judicial problems at the economic and political context level; the type and ownership of hospitals, absence of an on call physician, absence of clear job-descriptions for obstetricians and midwives, too many interventions in the delivery process and shortage of human resources and facilities at the organizational context level; distrust and insufficient collaborations between obstetricians and midwives from macro to micro level at the social context level; attitudes toward complications of C-section, reduced capabilities of obstetricians, midwives and residents at the individual professional level; and finally, at the innovation level, vaginal delivery is time consuming, imposes high stress levels and is unpredictable. Conclusion Changing service providers' behavior is not possible through presentation of scientific evidence alone. A multi-level and multidisciplinary approach using behavior change theories is unavoidable. In future studies, the effect of the barriers should be determined to help policy makers recognize the most effective interventional package.

  20. Utilization of electromigration in civil and environmental engineering--processes, transport rates and matrix changes.

    Science.gov (United States)

    Ottosen, Lisbeth M; Christensen, Iben V; Rorig-Dalgård, Inge; Jensen, Pernille E; Hansen, Henrik K

    2008-07-01

    Electromigration (movement of ions in an applied electric field) is utilized for supply or extraction of ions from various porous materials within both civil and environmental engineering. In civil engineering, most research has been conducted on the removal of chlorides from concrete to hinder reinforcement corrosion while in environmental engineering remediation of heavy metal polluted soil is the issue most studied. Never the less, experiments have been conducted with utilization for several other materials and purposes within both engineering fields. Even though there are many topics of common interest in the use of electromigration for the two fields, there is no tradition for collaboration. The present paper is a review with the aim of pointing out areas of shared interest. Focus is laid on the purposes of the different processes, transport rates of various ions in different materials and on changes in the matrix itself. Desorption and dissolution of the target elements into ionic form is a key issue to most of the processes, and can be the limiting step. The removal rate is generally below 1 cm day(- 1), but it can be much less than 1 mm day(- 1) when desorption is slow and insufficient. Matrix changes occurs under the action of the applied electric field and it includes both physico-chemical and hydrological changes. Some of the solid phases is weathered and new can be formed. Increased fundamental understanding of the effects and side effects, when applying the electric field to a porous material, can lead to improvement of the known technologies and possibly to new applications.

  1. The Accelerating Spin Of 9P/Tempel 1

    Science.gov (United States)

    Belton, Michael J.; Drahus, M.

    2007-10-01

    Deep Impact approach photometry has been analyzed using the dynamical techniques introduced by Drahus and Waniak (2006). Clear indications of acceleration (0.70 +/- 0.24 x 10-7 h-2) in the spin rate are found together with a spin period of 40.850 +/- 0.017 h at the mid point of the data set (June 2.38304, 2005 UT). This measurement of acceleration in the spin is similar to that deduced independently from a combination of spin rate measurements derived from the Deep Impact Earth-based campaign (Meech et al. 2005), Spitzer observations (Lisse et al. 2005), and Deep Impact approach data (A'Hearn et al. 2005). Estimates of the spin rate from these sources (Belton et al. 2007) at epochs between 1999 and 2006 were coupled through the 2005 perihelion passage using a heuristic spin rate change model based on non-gravitational torques due to the outflow of H2O. This model yields a preliminary estimate of 1.15×10-7 h-2 for the acceleration of the spin at the mid point of the data set; it also suggests that the net torque is dominated by activity in the Northern hemisphere of the nucleus. Although non-constant periodicities have been reported for a few comets before, the evidence has never been detected as clearly and unambiguously as for 9P/Tempel 1. This discovery strongly impacts the preparations for the Stardust-NExT mission (http://stardust.jpl.nasa.gov/news/status/070703.html) scheduled to arrive at the comet in 2011. References: A'Hearn, M.F. and 32 colleagues, 2005. Science 310, 258-264. Belton, M.J.S. and 35 colleagues, 2007. In preparation. Drahus, M, and Waniak, W. 2006, Icarus 185, 544 Lisse, C.M and 8 colleagues 2005. Astrophys. J. 625, L139-L142. Meech, K.J. and 208 colleagues, 2005. Science 310, 265-269.

  2. Genetic contribution to rate of change in functional abilities among Danish twins aged 75 years or more

    DEFF Research Database (Denmark)

    Christensen, Kaare; Gaist, David; Vaupel, James W

    2002-01-01

    In a previous cross-sectional study of twins, the authors found evidence of a substantial genetic influence on functional abilities among elderly women. It has been suggested that rate of change in functional abilities over time could underlie such findings and that rate-of-change phenotypes may......, and a valid and reliable measure of rate of change in a phenotype that had previously shown substantial heritability in cross-sectional analyses in the same twin population. Still, the present study revealed only a modest and nonsignificant genetic influence on rate of change, which suggests that detection...... of polymorphisms influencing rate of change in functional abilities among the elderly may prove to be difficult....

  3. The rate of change in declining steroid hormones: a new parameter of healthy aging in men?

    Science.gov (United States)

    Walther, Andreas; Philipp, Michel; Lozza, Niclà; Ehlert, Ulrike

    2016-01-01

    Research on healthy aging in men has increasingly focused on age-related hormonal changes. Testosterone (T) decline is primarily investigated, while age-related changes in other sex steroids (dehydroepiandrosterone [DHEA], estradiol [E2], progesterone [P]) are mostly neglected. An integrated hormone parameter reflecting aging processes in men has yet to be identified. 271 self-reporting healthy men between 40 and 75 provided both psychometric data and saliva samples for hormone analysis. Correlation analysis between age and sex steroids revealed negative associations for the four sex steroids (T, DHEA, E2, and P). Principal component analysis including ten salivary analytes identified a principal component mainly unifying the variance of the four sex steroid hormones. Subsequent principal component analysis including the four sex steroids extracted the principal component of declining steroid hormones (DSH). Moderation analysis of the association between age and DSH revealed significant moderation effects for psychosocial factors such as depression, chronic stress and perceived general health. In conclusion, these results provide further evidence that sex steroids decline in aging men and that the integrated hormone parameter DSH and its rate of change can be used as biomarkers for healthy aging in men. Furthermore, the negative association of age and DSH is moderated by psychosocial factors. PMID:27589836

  4. The influence of model structure on groundwater recharge rates in climate-change impact studies

    Science.gov (United States)

    Moeck, Christian; Brunner, Philip; Hunkeler, Daniel

    2016-08-01

    Numerous modeling approaches are available to provide insight into the relationship between climate change and groundwater recharge. However, several aspects of how hydrological model choice and structure affect recharge predictions have not been fully explored, unlike the well-established variability of climate model chains—combination of global climate models (GCM) and regional climate models (RCM). Furthermore, the influence on predictions related to subsoil parameterization and the variability of observation data employed during calibration remain unclear. This paper compares and quantifies these different sources of uncertainty in a systematic way. The described numerical experiment is based on a heterogeneous two-dimensional reference model. Four simpler models were calibrated against the output of the reference model, and recharge predictions of both reference and simpler models were compared to evaluate the effect of model structure on climate-change impact studies. The results highlight that model simplification leads to different recharge rates under climate change, especially under extreme conditions, although the different models performed similarly under historical climate conditions. Extreme weather conditions lead to model bias in the predictions and therefore must be considered. Consequently, the chosen calibration strategy is important and, if possible, the calibration data set should include climatic extremes in order to minimise model bias introduced by the calibration. The results strongly suggest that ensembles of climate projections should be coupled with ensembles of hydrogeological models to produce credible predictions of future recharge and with the associated uncertainties.

  5. Prediction of hospital mortality by changes in the estimated glomerular filtration rate (eGFR).

    LENUS (Irish Health Repository)

    Berzan, E

    2015-03-01

    Deterioration of physiological or laboratory variables may provide important prognostic information. We have studied whether a change in estimated glomerular filtration rate (eGFR) value calculated using the (Modification of Diet in Renal Disease (MDRD) formula) over the hospital admission, would have predictive value. An analysis was performed on all emergency medical hospital episodes (N = 61964) admitted between 1 January 2002 and 31 December 2011. A stepwise logistic regression model examined the relationship between mortality and change in renal function from admission to discharge. The fully adjusted Odds Ratios (OR) for 5 classes of GFR deterioration showed a stepwise increased risk of 30-day death with OR\\'s of 1.42 (95% CI: 1.20, 1.68), 1.59 (1.27, 1.99), 2.71 (2.24, 3.27), 5.56 (4.54, 6.81) and 11.9 (9.0, 15.6) respectively. The change in eGFR during a clinical episode, following an emergency medical admission, powerfully predicts the outcome.

  6. Toward Capturing Momentary Changes of Heart Rate Variability by a Dynamic Analysis Method.

    Directory of Open Access Journals (Sweden)

    Haoshi Zhang

    Full Text Available The analysis of heart rate variability (HRV has been performed on long-term electrocardiography (ECG recordings (12~24 hours and short-term recordings (2~5 minutes, which may not capture momentary change of HRV. In this study, we present a new method to analyze the momentary HRV (mHRV. The ECG recordings were segmented into a series of overlapped HRV analysis windows with a window length of 5 minutes and different time increments. The performance of the proposed method in delineating the dynamics of momentary HRV measurement was evaluated with four commonly used time courses of HRV measures on both synthetic time series and real ECG recordings from human subjects and dogs. Our results showed that a smaller time increment could capture more dynamical information on transient changes. Considering a too short increment such as 10 s would cause the indented time courses of the four measures, a 1-min time increment (4-min overlapping was suggested in the analysis of mHRV in the study. ECG recordings from human subjects and dogs were used to further assess the effectiveness of the proposed method. The pilot study demonstrated that the proposed analysis of mHRV could provide more accurate assessment of the dynamical changes in cardiac activity than the conventional measures of HRV (without time overlapping. The proposed method may provide an efficient means in delineating the dynamics of momentary HRV and it would be worthy performing more investigations.

  7. Vector spin modeling for magnetic tunnel junctions with voltage dependent effects

    International Nuclear Information System (INIS)

    Manipatruni, Sasikanth; Nikonov, Dmitri E.; Young, Ian A.

    2014-01-01

    Integration and co-design of CMOS and spin transfer devices requires accurate vector spin conduction modeling of magnetic tunnel junction (MTJ) devices. A physically realistic model of the MTJ should comprehend the spin torque dynamics of nanomagnet interacting with an injected vector spin current and the voltage dependent spin torque. Vector spin modeling allows for calculation of 3 component spin currents and potentials along with the charge currents/potentials in non-collinear magnetic systems. Here, we show 4-component vector spin conduction modeling of magnetic tunnel junction devices coupled with spin transfer torque in the nanomagnet. Nanomagnet dynamics, voltage dependent spin transport, and thermal noise are comprehended in a self-consistent fashion. We show comparison of the model with experimental magnetoresistance (MR) of MTJs and voltage degradation of MR with voltage. Proposed model enables MTJ circuit design that comprehends voltage dependent spin torque effects, switching error rates, spin degradation, and back hopping effects

  8. Ontogenetic changes in food intake and digestion rate of the herbivorous marine iguana (Amblyrhynchus cristatus, Bell).

    Science.gov (United States)

    Wikelski, M; Gall, B; Trillmich, F

    1993-06-01

    Young reptiles have higher relative energy demands than adults, but the proposed ontogenetic changes in diet to fulfil these demands were not found in the algae-eating Galápagos marine iguanas on Santa Fé. Feeding and digestion rates were investigated to analyse how young achieve higher energy intake. Daily food intake of free ranging marine iguana hatchlings (6-11 months old) was about one third that of adults, but relative intake (g dry mass · g -1 wet mass · day -1 ) was four times higher in the hatchlings. During feeding experiments, relative daily food intake of hatchling marine iguanas was approximately three times higher than that of adults (0.042 vs 0.013 g dry mass · g -0.8 wet mass · day -1 ), and mean gut passage time was two times shorter (5 vs 10 days). The hatchlings also maintained high body temperatures (36.7° C) even under relatively cool day-time air temperatures of 32° C. Apparent digestibility of algal food measured both during feeding trials and by Mn 2+ AAS (atomic absorption spectrometry) for free-ranging iguanas was 70%, independent of body size and temperature. The red algae prevailing in the diet were high in protein (30% dry mass) and energy (12.1 kJ/g dry mass). Diving iguanas had higher rates of energy intake than intertidal foragers, but daily intake was less. Maintenance of high body temperature enabled hatchlings to achieve high digestion rates and, combined with high relative intake, thus achieve sufficient energy intake for rapid growth despite higher mass specific metabolic rates. Estimates of biomass of marine iguanas and their algal food are given for a section of coastline on Santa Fé.

  9. Numerical modelling of landscape and sediment flux response to precipitation rate change

    Directory of Open Access Journals (Sweden)

    J. J. Armitage

    2018-02-01

    Full Text Available Laboratory-scale experiments of erosion have demonstrated that landscapes have a natural (or intrinsic response time to a change in precipitation rate. In the last few decades there has been growth in the development of numerical models that attempt to capture landscape evolution over long timescales. However, there is still an uncertainty regarding the validity of the basic assumptions of mass transport that are made in deriving these models. In this contribution we therefore return to a principal assumption of sediment transport within the mass balance for surface processes; we explore the sensitivity of the classic end-member landscape evolution models and the sediment fluxes they produce to a change in precipitation rates. One end-member model takes the mathematical form of a kinetic wave equation and is known as the stream power model, in which sediment is assumed to be transported immediately out of the model domain. The second end-member model is the transport model and it takes the form of a diffusion equation, assuming that the sediment flux is a function of the water flux and slope. We find that both of these end-member models have a response time that has a proportionality to the precipitation rate that follows a negative power law. However, for the stream power model the exponent on the water flux term must be less than one, and for the transport model the exponent must be greater than one, in order to match the observed concavity of natural systems. This difference in exponent means that the transport model generally responds more rapidly to an increase in precipitation rates, on the order of 105 years for post-perturbation sediment fluxes to return to within 50 % of their initial values, for theoretical landscapes with a scale of 100×100 km. Additionally from the same starting conditions, the amplitude of the sediment flux perturbation in the transport model is greater, with much larger sensitivity to catchment size. An

  10. Numerical modelling of landscape and sediment flux response to precipitation rate change

    Science.gov (United States)

    Armitage, John J.; Whittaker, Alexander C.; Zakari, Mustapha; Campforts, Benjamin

    2018-02-01

    Laboratory-scale experiments of erosion have demonstrated that landscapes have a natural (or intrinsic) response time to a change in precipitation rate. In the last few decades there has been growth in the development of numerical models that attempt to capture landscape evolution over long timescales. However, there is still an uncertainty regarding the validity of the basic assumptions of mass transport that are made in deriving these models. In this contribution we therefore return to a principal assumption of sediment transport within the mass balance for surface processes; we explore the sensitivity of the classic end-member landscape evolution models and the sediment fluxes they produce to a change in precipitation rates. One end-member model takes the mathematical form of a kinetic wave equation and is known as the stream power model, in which sediment is assumed to be transported immediately out of the model domain. The second end-member model is the transport model and it takes the form of a diffusion equation, assuming that the sediment flux is a function of the water flux and slope. We find that both of these end-member models have a response time that has a proportionality to the precipitation rate that follows a negative power law. However, for the stream power model the exponent on the water flux term must be less than one, and for the transport model the exponent must be greater than one, in order to match the observed concavity of natural systems. This difference in exponent means that the transport model generally responds more rapidly to an increase in precipitation rates, on the order of 105 years for post-perturbation sediment fluxes to return to within 50 % of their initial values, for theoretical landscapes with a scale of 100×100 km. Additionally from the same starting conditions, the amplitude of the sediment flux perturbation in the transport model is greater, with much larger sensitivity to catchment size. An important finding is that

  11. 34 CFR 668.184 - Determining cohort default rates for institutions that have undergone a change in status.

    Science.gov (United States)

    2010-07-01

    ... 34 Education 3 2010-07-01 2010-07-01 false Determining cohort default rates for institutions that have undergone a change in status. 668.184 Section 668.184 Education Regulations of the Offices of the... ASSISTANCE GENERAL PROVISIONS Two Year Cohort Default Rates § 668.184 Determining cohort default rates for...

  12. Changes of respiration and of specific growth rate during cell cycle of yeast cells of different genealogical age.

    Science.gov (United States)

    Vraná, D

    1988-01-01

    When investigating changes of respiratory activity during the cell cycle of mother and daughter Candida cells significant oscillations of specific rate of oxygen consumption were detected; specific growth rate also varied. The oscillations were less pronounced when the inoculum was obtained from the chemostat at the high dilution rates of 0.25 and 0.35/h.

  13. Dynamic nuclear spin polarization

    Energy Technology Data Exchange (ETDEWEB)

    Stuhrmann, H.B. [GKSS-Forschungszentrum Geesthacht GmbH (Germany)

    1996-11-01

    Polarized neutron scattering from dynamic polarized targets has been applied to various hydrogenous materials at different laboratories. In situ structures of macromolecular components have been determined by nuclear spin contrast variation with an unprecedented precision. The experiments of selective nuclear spin depolarisation not only opened a new dimension to structural studies but also revealed phenomena related to propagation of nuclear spin polarization and the interplay of nuclear polarisation with the electronic spin system. The observation of electron spin label dependent nuclear spin polarisation domains by NMR and polarized neutron scattering opens a way to generalize the method of nuclear spin contrast variation and most importantly it avoids precontrasting by specific deuteration. It also likely might tell us more about the mechanism of dynamic nuclear spin polarisation. (author) 4 figs., refs.

  14. Structural growth trajectories and rates of change in the first 3 months of infant brain development.

    Science.gov (United States)

    Holland, Dominic; Chang, Linda; Ernst, Thomas M; Curran, Megan; Buchthal, Steven D; Alicata, Daniel; Skranes, Jon; Johansen, Heather; Hernandez, Antonette; Yamakawa, Robyn; Kuperman, Joshua M; Dale, Anders M

    2014-10-01

    The very early postnatal period witnesses extraordinary rates of growth, but structural brain development in this period has largely not been explored longitudinally. Such assessment may be key in detecting and treating the earliest signs of neurodevelopmental disorders. To assess structural growth trajectories and rates of change in the whole brain and regions of interest in infants during the first 3 months after birth. Serial structural T1-weighted and/or T2-weighted magnetic resonance images were obtained for 211 time points from 87 healthy term-born or term-equivalent preterm-born infants, aged 2 to 90 days, between October 5, 2007, and June 12, 2013. We segmented whole-brain and multiple subcortical regions of interest using a novel application of Bayesian-based methods. We modeled growth and rate of growth trajectories nonparametrically and assessed left-right asymmetries and sexual dimorphisms. Whole-brain volume at birth was approximately one-third of healthy elderly brain volume, and did not differ significantly between male and female infants (347 388 mm3 and 335 509 mm3, respectively, P = .12). The growth rate was approximately 1%/d, slowing to 0.4%/d by the end of the first 3 months, when the brain reached just more than half of elderly adult brain volume. Overall growth in the first 90 days was 64%. There was a significant age-by-sex effect leading to widening separation in brain sizes with age between male and female infants (with male infants growing faster than females by 200.4 mm3/d, SE = 67.2, P = .003). Longer gestation was associated with larger brain size (2215 mm3/d, SE = 284, P = 4×10-13). The expected brain size of an infant born one week earlier than average was 5% smaller than average; at 90 days it will not have caught up, being 2% smaller than average. The cerebellum grew at the highest rate, more than doubling in 90 days, and the hippocampus grew at the slowest rate, increasing by 47% in 90 days. There was left

  15. Changes of deceleration and acceleration capacity of heart rate in patients with acute hemispheric ischemic stroke

    Directory of Open Access Journals (Sweden)

    Xu YH

    2016-03-01

    Full Text Available Yan-Hong Xu,1 Xing-De Wang,2 Jia-Jun Yang,1 Li Zhou,2 Yong-Chao Pan1 1Department of Neurology, 2Department of Cardiology, Shanghai Jiao Tong University Affiliated Sixth People’s Hospital, Shanghai, People’s Republic of China Background and purpose: Autonomic dysfunction is common after stroke, which is correlated with unfavorable outcome. Phase-rectified signal averaging is a newly developed technique for assessing cardiac autonomic function, by detecting sympathetic and vagal nerve activity separately through calculating acceleration capacity (AC and deceleration capacity (DC of heart rate. In this study, we used this technique for the first time to investigate the cardiac autonomic function of patients with acute hemispheric ischemic stroke. Methods: A 24-hour Holter monitoring was performed in 63 patients with first-ever acute ischemic stroke in hemisphere and sinus rhythm, as well as in 50 controls with high risk of stroke. DC, AC, heart rate variability parameters, standard deviation of all normal-to-normal intervals (SDNN, and square root of the mean of the sum of the squares of differences between adjacent normal-to-normal intervals (RMSSD were calculated. The National Institutes of Health Stroke Scale (NIHSS was used to assess the severity of stroke. We analyzed the changes of DC, AC, SDNN, and RMSSD and also studied the correlations between these parameters and NIHSS scores. Results: The R–R (R wave to R wave on electrocardiogram intervals, DC, AC, and SDNN in the cerebral infarction group were lower than those in controls (P=0.003, P=0.002, P=0.006, and P=0.043, but the difference of RMSSD and the D-value and ratio between absolute value of AC (|AC| and DC were not statistically significant compared with those in controls. The DC of the infarction group was significantly correlated with |AC|, SDNN, and RMSSD (r=0.857, r=0.619, and r=0.358; P=0.000, P=0.000, and P=0.004. Correlation analysis also showed that DC, |AC|, and SDNN

  16. Nitrogen Addition Changes the Stoichiometry and Growth Rate of Different Organs in Pinus tabuliformis Seedlings

    Directory of Open Access Journals (Sweden)

    Hang Jing

    2017-11-01

    Full Text Available Background: Nitrogen (N deposition could influence plant stoichiometry and growth rate and thus alter the structure and function of the ecosystem. However, the mechanism by which N deposition changes the stoichiometry and relative growth rate (RGR of plant organs, especially roots with different diameters, is unclear.Methods: We created a gradient of N availability (0–22.4 g N m-2 year-1 for Pinus tabuliformis seedlings for 3 years and examined changes in the carbon (C:N:phosphorus (P ratios and RGRs of the leaves, stems, and roots with four diameter classes (finest roots, <0.5 mm; finer roots, 0.5–1 mm; middle roots, 1–2 mm; and coarse roots, >2 mm.Results: (1 N addition significantly increased the C and N contents of the leaves and whole roots, the C content of the stems, the N:P ratios of the leaves and stems, and the C:P ratio of the whole roots. (2 In the root system, the C:N ratio of the finest roots and the C:P ratios of the finest and finer roots significantly changed with N addition. The N:P ratios of the finest, finer, and middle roots significantly increased with increasing amount of N added. The stoichiometric responses of the roots were more sensitive to N addition than those of the other organs (3 The RGR of all the organs significantly increased at low N addition levels (2.8–11.2 g N m-2 year-1 but decreased at high N addition levels (22.4 g N m-2 year-1. (4 The RGRs of the whole seedlings and leaves were not significantly correlated with their N:P ratios at low and high N addition levels. By contrast, the RGRs of the stems and roots showed a significantly positive correlation with their own N:P ratio only at low N addition level.Conclusion: Addition of N affected plant growth by altering the contents of C and N; the ratios of C, N, and P; and the RGRs of the organs. RGR is correlated with the N:P ratios of the stems and roots at low N addition level but not at high N addition level. This finding is inconsistent with the

  17. A theoretical framework for quantifying blood volume flow rate from dynamic angiographic data and application to vessel-encoded arterial spin labeling MRI ☆

    OpenAIRE

    Okell, Thomas W.; Chappell, Michael A.; Jezzard, Peter

    2013-01-01

    Angiographic methods can provide valuable information on vessel morphology and hemodynamics, but are often qualitative in nature, somewhat limiting their ability for comparison across arteries and subjects. In this work we present a method for quantifying absolute blood volume flow rates within large vessels using dynamic angiographic data. First, a kinetic model incorporating relative blood volume, bolus dispersion and signal attenuation is fitted to the data. A self-calibration method is al...

  18. Climate-induced seasonal changes in smallmouth bass growth rate potential at the southern range extent

    Science.gov (United States)

    Middaugh, Christopher R.; Kessinger, Brin; Magoulick, Daniel D.

    2018-01-01

    Temperature increases due to climate change over the coming century will likely affect smallmouth bass (Micropterus dolomieu) growth in lotic systems at the southern extent of their native range. However, the thermal response of a stream to warming climate conditions could be affected by the flow regime of each stream, mitigating the effects on smallmouth bass populations. We developed bioenergetics models to compare change in smallmouth bass growth rate potential (GRP) from present to future projected monthly stream temperatures across two flow regimes: runoff and groundwater-dominated. Seasonal differences in GRP between stream types were then compared. The models were developed for fourteen streams within the Ozark–Ouachita Interior Highlands in Arkansas, Oklahoma and Missouri, USA, which contain smallmouth bass. In our simulations, smallmouth bass mean GRP during summer months decreased by 0.005 g g−1 day−1 in runoff streams and 0.002 g g−1 day−1 in groundwater streams by the end of century. Mean GRP during winter, fall and early spring increased under future climate conditions within both stream types (e.g., 0.00019 g g−1 day−1 in runoff and 0.0014 g g−1 day−1 in groundwater streams in spring months). We found significant differences in change in GRP between runoff and groundwater streams in three seasons in end-of-century simulations (spring, summer and fall). Potential differences in stream temperature across flow regimes could be an important habitat component to consider when investigating effects of climate change as fishes from various flow regimes that are relatively close geographically could be affected differently by warming climate conditions.

  19. Increased cesarean section rate in Central Saudi Arabia: a change in practice or different maternal characteristics

    Directory of Open Access Journals (Sweden)

    Al-Kadri HM

    2015-07-01

    significantly increased within the studied population. The increased rate of CS may be related to a change in physician’s practice rather than a change in maternal characteristics, and it appears to be reducible.Keywords: cesarean section, maternal morbidity, neonatal morbidity, cesarean section rate

  20. Thermal-induced changes on the properties of spin-coated P3HT:C60 thin films for solar cell applications

    CSIR Research Space (South Africa)

    Motaung, DE

    2009-09-01

    Full Text Available The thermal transition behaviour, optical and structural properties of spin-coated P3HT:C60 blended films with different C60 ratios were investigated using differential scanning calorimetry (DSC), thermo-gravimetric analysis (TGA), ultraviolet...

  1. Spin at Lausanne

    International Nuclear Information System (INIS)

    Anon.

    1980-01-01

    From 25 September to 1 October, some 150 spin enthusiasts gathered in Lausanne for the 1980 International Symposium on High Energy Physics with Polarized Beams and Polarized Targets. The programme was densely packed, covering physics interests with spin as well as the accelerator and target techniques which make spin physics possible

  2. Spin-torque transistor

    NARCIS (Netherlands)

    Bauer, G.E.W.; Brataas, A.; Tserkovnyak, Y.; Van Wees, B.J.

    2003-01-01

    A magnetoelectronic thin-film transistor is proposed that can display negative differential resistance and gain. The working principle is the modulation of the soure–drain current in a spin valve by the magnetization of a third electrode, which is rotated by the spin-torque created by a control spin

  3. Coherent collisional spin dynamics in optical lattices.

    Science.gov (United States)

    Widera, Artur; Gerbier, Fabrice; Fölling, Simon; Gericke, Tatjana; Mandel, Olaf; Bloch, Immanuel

    2005-11-04

    We report on the observation of coherent, purely collisionally driven spin dynamics of neutral atoms in an optical lattice. For high lattice depths, atom pairs confined to the same lattice site show weakly damped Rabi-type oscillations between two-particle Zeeman states of equal magnetization, induced by spin-changing collisions. Moreover, measurement of the oscillation frequency allows for precise determination of the spin-changing collisional coupling strengths, which are directly related to fundamental scattering lengths describing interatomic collisions at ultracold temperatures.

  4. The impact of changes in self-rated general health on 28-year mortality among middle-aged Danes

    DEFF Research Database (Denmark)

    Nielsen, Anni Brit Sternhagen; Siersma, Volkert; Kreiner, Svend

    2009-01-01

    OBJECTIVE: Self-rated general health (SRH) predicts future mortality. SRH may change, and these changes may alter the mortality risk. All-cause mortality until the age of 68 and its association with changes in SRH from the age of 40-45, 45-51, and 51-60 years was examined in a cohort of Danes...

  5. Obesity-associated metabolic changes influence resting and peak heart rate in women and men.

    Science.gov (United States)

    Strandheim, Astrid; Halland, Hilde; Saeed, Sahrai; Cramariuc, Dana; Hetland, Trude; Lønnebakken, Mai Tone; Gerdts, Eva

    2015-01-01

    To study the relationship between obesity and heart rate (HR) in women and men. We studied 241 overweight and obese subjects without known heart disease. All subjects underwent ergospirometry during maximal exercise testing on treadmill and recording of body composition, electrocardiogram and clinic and ambulatory blood pressure. Women (n = 132) were slightly older and had higher fat mass, but lower weight, blood pressure and prevalence of metabolic syndrome (MetS) than men (n = 109) (all p obesity and hypertension did not differ. A significant interaction between sex and HR was demonstrated (p men (all p men, while lower HbA1c and absence of obesity were the main covariates in women in multivariate analyses (all p obesity and obesity-associated metabolic changes influenced both resting and peak exercise HR.

  6. Understanding Rates of Marijuana Use and Consequences Among Adolescents in a Changing Legal Landscape.

    Science.gov (United States)

    D'Amico, Elizabeth J; Tucker, Joan S; Pedersen, Eric R; Shih, Regina A

    2017-01-01

    There is not one answer to address whether marijuana use has increased, decreased, or stayed the same given changes in state legalization of medical and non-medical marijuana in the USA. Evidence suggests some health benefits for medical marijuana; however, initiation of marijuana use is a risk factor for developing problem cannabis use. Though use rates have remained stable over recent years, about one in three 10th graders report marijuana use, most adolescents do not view the drug as harmful, and over 650,000 youth aged 12 to 17 struggle with cannabis use disorder. Although the health benefits of medical marijuana are becoming better understood, more research is needed. Intervention and prevention programs must better address effects of marijuana, acknowledging that while there may be some benefits medically, marijuana use can affect functioning during adolescence when the brain is still developing.

  7. Dynamic Changes in Heart Rate Variability and Nasal Airflow Resistance during Nasal Allergen Provocation Test

    Science.gov (United States)

    Seppänen, Tiina M.; Alho, Olli-Pekka; Seppänen, Tapio

    2016-01-01

    Allergic rhinitis is a major chronic respiratory disease and an immunoneuronal disorder. We aimed at providing further knowledge on the function of the neural system in nasal allergic reaction. Here, a method to assess simultaneously the nasal airflow resistance and the underlying function of autonomic nervous system (ANS) is presented and used during the nasal provocation of allergic and nonallergic subjects. Continuous nasal airflow resistance and spectral heart rate variability parameters show in detail the timing and intensity differences in subjects' reactions. After the provocation, the nasal airflow resistance of allergic subjects showed a positive trend, whereas LF/HF (Low Frequency/High Frequency) ratio and LF power showed a negative trend. This could imply a gradual sympathetic withdrawal in allergic subjects after the allergen provocation. The groups differed significantly by these physiological descriptors. The proposed method opens entirely new opportunities to research accurately concomitant changes in nasal breathing function and ANS. PMID:27196870

  8. Dynamic Changes in Heart Rate Variability and Nasal Airflow Resistance during Nasal Allergen Provocation Test

    Directory of Open Access Journals (Sweden)

    Tiina M. Seppänen

    2016-01-01

    Full Text Available Allergic rhinitis is a major chronic respiratory disease and an immunoneuronal disorder. We aimed at providing further knowledge on the function of the neural system in nasal allergic reaction. Here, a method to assess simultaneously the nasal airflow resistance and the underlying function of autonomic nervous system (ANS is presented and used during the nasal provocation of allergic and nonallergic subjects. Continuous nasal airflow resistance and spectral heart rate variability parameters show in detail the timing and intensity differences in subjects’ reactions. After the provocation, the nasal airflow resistance of allergic subjects showed a positive trend, whereas LF/HF (Low Frequency/High Frequency ratio and LF power showed a negative trend. This could imply a gradual sympathetic withdrawal in allergic subjects after the allergen provocation. The groups differed significantly by these physiological descriptors. The proposed method opens entirely new opportunities to research accurately concomitant changes in nasal breathing function and ANS.

  9. Spin currents from Helium in intense-field photo-ionization

    International Nuclear Information System (INIS)

    Bhattacharyya, S; Mukherjee, Mahua; Chakrabarti, J; Faisal, F H M

    2007-01-01

    Spin dynamics is studied by computing spin-dependent ionization current of He in intense laser field in relativistic field theoretic method. Spin-flip and spin-asymmetry in current generation is obtained with circularly polarized light. The spin-flip is a dynamical effect of intense laser field on an ionized spinning electron. Transformation properties of the up and down spin ionization amplitudes show that the sign of spin can be controlled by a change of helicity of the laser photons from outside

  10. Uptake rate of cationic mitochondrial inhibitor MKT-077 determines cellular oxygen consumption change in carcinoma cells.

    Directory of Open Access Journals (Sweden)

    John L Chunta

    Full Text Available OBJECTIVE: Since tumor radiation response is oxygen-dependent, radiosensitivity can be enhanced by increasing tumor oxygenation. Theoretically, inhibiting cellular oxygen consumption is the most efficient way to increase oxygen levels. The cationic, rhodacyanine dye-analog MKT-077 inhibits mitochondrial respiration and could be an effective metabolic inhibitor. However, the relationship between cellular MKT-077 uptake and metabolic inhibition is unknown. We hypothesized that rat and human mammary carcinoma cells would take up MKT-077, causing a decrease in oxygen metabolism related to drug uptake. METHODS: R3230Ac rat breast adenocarcinoma cells were exposed to MKT-077. Cellular MKT-077 concentration was quantified using spectroscopy, and oxygen consumption was measured using polarographic electrodes. MKT-077 uptake kinetics were modeled by accounting for uptake due to both the concentration and potential gradients across the plasma and mitochondrial membranes. These kinetic parameters were used to model the relationship between MKT-077 uptake and metabolic inhibition. MKT-077-induced changes in oxygen consumption were also characterized in MDA-MB231 human breast carcinoma cells. RESULTS: Cells took up MKT-077 with a time constant of ∼1 hr, and modeling showed that over 90% of intracellular MKT-077 was bound or sequestered, likely by the mitochondria. The uptake resulted in a rapid decrease in oxygen consumption, with a time constant of ∼30 minutes. Surprisingly the change in oxygen consumption was proportional to uptake rate, not cellular concentration. MKT-077 proved a potent metabolic inhibitor, with dose-dependent decreases of 45-73% (p = 0.003. CONCLUSIONS: MKT-077 caused an uptake rate-dependent decrease in cellular metabolism, suggesting potential efficacy for increasing tumor oxygen levels and radiosensitivity in vivo.

  11. Embryonic developmental rates of northern grasshoppers (Orthoptera: Acrididae): implications for climate change and habitat management.

    Science.gov (United States)

    Fielding, Dennis J; Defoliart, Linda S

    2010-10-01

    Accurate models of temperature-dependent embryonic developmental rates are important to assess the effects of a changing climate on insect life cycles and to suggest methods of population management by habitat manipulation. Embryonic development determines the life cycle of many species of grasshoppers, which, in cold climates, spend two winters in the egg stage. Increasing temperatures associated with climate change in the subarctic could potentiate a switch to a univoltine life cycle. However, egg hatch could be delayed by maintaining a closed vegetative canopy, which would lower soil temperatures by shading the soil surface. Prediapause and postdiapause embryonic developmental rates were measured in the laboratory over a wide range of temperatures for Melanoplus borealis Fieber and Melanoplus sanguinipes F. (Orthoptera: Acrididae) A model was fit to the data and used to predict dates of egg hatch in the spring and prediapause development in the fall under different temperature regimens. Actual soil temperatures were recorded at several locations over 5 yr. To simulate climate warming, 2, 3, or 4°C was added to each hourly recorded temperature. Results suggest that a 2, 3, or 4°C increase in soil temperatures will result in eggs hatching ≈ 3, 5, or 7 d earlier, respectively. An increase of 3°C would be required to advance prediapause development enough to allow for a portion of the population to be univoltine in warmer years. To simulate shading, 2 and 4°C were subtracted from observed temperatures. A 4°C decrease in temperatures could potentially delay hatch by 8 d.

  12. Decomposition behavior of hemicellulose and lignin in the step-change flow rate liquid hot water.

    Science.gov (United States)

    Zhuang, Xinshu; Yu, Qiang; Wang, Wen; Qi, Wei; Wang, Qiong; Tan, Xuesong; Yuan, Zhenhong

    2012-09-01

    Hemicellulose and lignin are the main factors limiting accessibility of hydrolytic enzymes besides the crystallinity of cellulose. The decomposition behavior of hemicellulose and lignin in the step-change flow rate hot water system was investigated. Xylan removal increased from 64.53% for batch system (solid concentration 4.25% w/v, 18 min, 184°C) to 83.78% at high flow rates of 30 ml/min for 8 min, and then 10 ml/min for 10 min. Most of them (80-90%) were recovered as oligosaccharide. It was hypothesized that the flowing water could enhance the mass transfer to improve the sugars recovery. In addition, the solubilization mechanism of lignin in the liquid hot water was proposed according to the results of Fourier transform-infrared spectroscopy and scanning electron microscopy of the water-insoluble fraction and gas chromatography-mass spectrometry of the water-soluble fraction. It was proposed that lignin in the liquid hot water first migrated out of the cell wall in the form of molten bodies, and then flushed out of the reactor. A small quantity of them was further degraded into monomeric products such as vanillin, syringe aldehyde, coniferyl aldehyde, ferulic acid, and p-hydroxy-cinnamic acid. All of these observations would provide important information for the downstream processing, such as purification and concentration of sugars and the enzymatic digestion of residual solid.

  13. A parsimonious characterization of change in global age-specific and total fertility rates

    Science.gov (United States)

    2018-01-01

    This study aims to understand trends in global fertility from 1950-2010 though the analysis of age-specific fertility rates. This approach incorporates both the overall level, as when the total fertility rate is modeled, and different patterns of age-specific fertility to examine the relationship between changes in age-specific fertility and fertility decline. Singular value decomposition is used to capture the variation in age-specific fertility curves while reducing the number of dimensions, allowing curves to be described nearly fully with three parameters. Regional patterns and trends over time are evident in parameter values, suggesting this method provides a useful tool for considering fertility decline globally. The second and third parameters were analyzed using model-based clustering to examine patterns of age-specific fertility over time and place; four clusters were obtained. A country’s demographic transition can be traced through time by membership in the different clusters, and regional patterns in the trajectories through time and with fertility decline are identified. PMID:29377899

  14. Uneven futures of human lifespans: reckonings from Gompertz mortality rates, climate change, and air pollution.

    Science.gov (United States)

    Finch, Caleb E; Beltrán-Sánchez, Hiram; Crimmins, Eileen M

    2014-01-01

    The past 200 years have enabled remarkable increases in human lifespans through improvements in the living environment that have nearly eliminated infections as a cause of death through improved hygiene, public health, medicine, and nutrition. We argue that the limit to lifespan may be approaching. Since 1997, no one has exceeded Jeanne Calment's record of 122.5 years, despite an exponential increase of centenarians. Moreover, the background mortality may be approaching a lower limit. We calculate from Gompertz coefficients that further increases in longevity to approach a life expectancy of 100 years in 21st century cohorts would require 50% slower mortality rate accelerations, which would be a fundamental change in the rate of human aging. Looking into the 21st century, we see further challenges to health and longevity from the continued burning of fossil fuels that contribute to air pollution as well as global warming. Besides increased heat waves to which elderly are vulnerable, global warming is anticipated to increase ozone levels and facilitate the spread of pathogens. We anticipate continuing socioeconomic disparities in life expectancy.

  15. Seasonal changes of the infiltration rates in urban parks of Valencia City, Eastern Spain

    Science.gov (United States)

    Cerdà, Artemi; Keesstra, Saskia; Burguet, María; Pereira, Paulo; Esteban Lucas-Borja, Manuel; Martinez-Murillo, Juan F.

    2016-04-01

    Infiltration is a key process of the hydrological cycle. Infiltration also controls the soil water resources, and the development of the vegetation, and moreover, in the Mediterranean, determines the runoff generation (Cerdà, 1996; 1997; 2001). In the Mediterranean, the infiltration in forest soils shows high spatial variability and seasonal and temporal changes (Cerdà, 1999; Bodí and Cerdà, 2009) and is being affected by forest fires (Cerdà, 1998), which introduce a new temporal change in the seasonality of the infiltration rates. Although the forest soils are well assessed, there is no information about the infiltration in urban areas in Mediterranean cities. The Mediterranean dense urban systems use to be treated as impermeable areas. However, the cities show areas covered by vegetation and with soils that allow the rainfall to infiltrate. Those areas are mainly the parks. In order to shed some light on the infiltration capacity of the soils of the urban area of Valencia city 30 rainfall simulations experiments (Cerdà, 1996) and 90 ring infiltrometer (10 cm diameter) measurements were carried out in January 2011, and they were repeated in July 2011, to compare wet (19.4 % of soil moisture) and dry (5.98 % of soil moisture) soils. The infiltration curves where fitted to the Horton (1933) equation and they lasted for 1 hour. The results show that the infiltration is 11 times higher when measured with ring infiltrometer than with the simulated rainfall at 55 mmh-1, and that the infiltration rates where higher in summer than in winter: 2.01 higher for the ring infiltrometer, and 1.45 higher when measured with the rainfall simulator. In comparison to the soils from the forest areas, the infiltration rate in the gardens were lower, with values of 10.23 and 21.65 mm h-1 in average for winter and summer when measured with the rainfall simulator. Similar results were found with the ring infiltrometer. It was also found a clear relationship between the vegetation

  16. The Effects of Changes in Reaction Rates on Simulations of Nova Explosions

    International Nuclear Information System (INIS)

    Starrfield, S.; Iliadis, C.; Hix, W. R.; Timmes, F. X.; Sparks, W. M.

    2007-01-01

    Classical novae participate in the cycle of Galactic chemical evolution in which grains and metal enriched gas in their ejecta, supplementing those of supernovae, AGB stars, and Wolf-Rayet stars, are a source of heavy elements for the ISM. Once in the diffuse gas, this material is mixed with the existing gases and then incorporated into young stars and planetary systems during star formation. Infrared observations have confirmed the presence of carbon, SiC, hydrocarbons, and oxygen-rich silicate grains in nova ejecta, suggesting that some fraction of the pre-solar grains identified in meteoritic material come from novae. The mean mass returned by a nova outburst to the ISM probably exceeds ∼ 2 x 10-4 M·. Using the observed nova rate of 35±11 per year in our Galaxy, it follows that novae introduce more than ∼ 7 x 10-3 M· yr-1 of processed matter into the ISM. Novae are expected to be the major source of 15N and 17O in the Galaxy and to contribute to the abundances of other isotopes in this atomic mass range. Here, we report on how changes in the nuclear reaction rates affect the properties of the outburst and alter the predictions of the contributions of novae to Galactic chemical evolution

  17. Voluntary leadership roles in religious groups and rates of change in functional status during older adulthood.

    Science.gov (United States)

    Hayward, R David; Krause, Neal

    2014-06-01

    Linear growth curve modeling was used to compare rates of change in functional status between three groups of older adults: Individuals holding voluntary lay leadership positions in a church, regular church attenders who were not leaders, and those not regularly attending church. Functional status was tracked longitudinally over a 4-year period in a national sample of 1,152 Black and White older adults whose religious backgrounds were either Christian or unaffiliated. Leaders had significantly slower trajectories of increase in both the number of physical impairments and the severity of those impairments. Although regular church attenders who were not leaders had lower mean levels of impairment on both measures, compared with those not regularly attending church, the two groups of non-leaders did not differ from one another in their rates of impairment increase. Leadership roles may contribute to longer maintenance of physical ability in late life, and opportunities for voluntary leadership may help account for some of the health benefits of religious participation.

  18. A parsimonious characterization of change in global age-specific and total fertility rates.

    Science.gov (United States)

    Pantazis, Athena; Clark, Samuel J

    2018-01-01

    This study aims to understand trends in global fertility from 1950-2010 though the analysis of age-specific fertility rates. This approach incorporates both the overall level, as when the total fertility rate is modeled, and different patterns of age-specific fertility to examine the relationship between changes in age-specific fertility and fertility decline. Singular value decomposition is used to capture the variation in age-specific fertility curves while reducing the number of dimensions, allowing curves to be described nearly fully with three parameters. Regional patterns and trends over time are evident in parameter values, suggesting this method provides a useful tool for considering fertility decline globally. The second and third parameters were analyzed using model-based clustering to examine patterns of age-specific fertility over time and place; four clusters were obtained. A country's demographic transition can be traced through time by membership in the different clusters, and regional patterns in the trajectories through time and with fertility decline are identified.

  19. [Changes in Upper Gastrointestinal Diseases according to Improvement of Helicobacter pylori Prevalence Rate in Korea].

    Science.gov (United States)

    Park, Soo Heon

    2015-04-01

    Helicobacter pylori can cause variety of upper gastrointestinal disorders such as peptic ulcer, mucosa associated lymphoid tissue (MALT)-lymphoma, and gastric cancer. The prevalence of H. pylori infection has significantly decreased in Korea since 1998 owing to active eradication of H. pylori. Along with its decrease, the prevalence of peptic ulcer has also decreased. However, the mean age of gastric ulcer increased and this is considered to be due to increase in NSAID prescription. Gastric cancer is one of the leading causes of cancer deaths in Korea and Japan, and IARC/WHO has classified H. pylori as class one carcinogen of gastric cancer. Despite the decreasing prevalence of H. pylori infection, the total number of gastric cancer in Korea has continuously increased from 2006 to 2011. Nevertheless, the 5 year survival rate of gastric cancer patients significantly increased from 42.8% in 1993 to 67% in 2010. This increase in survival rate seems to be mainly due to early detection of gastric cancer and endoscopic mucosal dissection treatment. Based on these findings, the prevalence of peptic ulcer is expected to decrease even more with H. pylori eradication therapy and NSAID will become the main cause of peptic ulcer. Although the prevalence of gastric cancer has not changed along with decreased the prevalence of H. pylori, gastric cancer is expected to decrease in the long run with the help of eradication therapy and endoscopic treatment of precancerous lesions.

  20. Neural correlates of fear-induced sympathetic response associated with the peripheral temperature change rate.

    Science.gov (United States)

    Yoshihara, Kazufumi; Tanabe, Hiroki C; Kawamichi, Hiroaki; Koike, Takahiko; Yamazaki, Mika; Sudo, Nobuyuki; Sadato, Norihiro

    2016-07-01

    Activation of the sympathetic nervous system is essential for coping with environmental stressors such as fearful stimuli. Recent human imaging studies demonstrated that activity in some cortical regions, such as the anterior cingulate cortex (ACC) and anterior insula cortex (aIC), is related to sympathetic activity. However, little is known about the functional brain connectivity related to sympathetic response to fearful stimuli. The participants were 32 healthy, right-handed volunteers. Functional magnetic resonance imaging (fMRI) was used to examine brain activity when watching horror and control movies. Fingertip temperature was taken during the scanning as a measure of sympathetic response. The movies were watched a second time, and the degree of fear (9-point Likert-type scale) was evaluated every three seconds. The brain activity of the ACC, bilateral aIC, and bilateral anterior prefrontal cortex (aPFC) was correlated with the change rate of fingertip temperature, with or without fearful stimuli. Functional connectivity analysis revealed significantly greater positive functional connectivity between the amygdala and the ACC and between the amygdala and the aIC when watching the horror movie than when watching the control movie. Whole-brain psycho-physiological interaction (PPI) analysis revealed that the functional connectivity between the left amygdala and the ACC was modulated according to the fear rating. Our results indicate that the increased functional connectivity between the left amygdala and the ACC represents a sympathetic response to fearful stimuli. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  1. Spin Transport in a Unitary Fermi Gas

    Science.gov (United States)

    Thywissen, Joseph

    2015-03-01

    We study spin transport in a quantum degenerate Fermi gas of 40K near an s-wave interaction resonance. The starting point of our measurements is a transversely spin-polarized gas, where each atom is in a superposition of the lowest two Zeeman eigenstates. In the presence of an external gradient, a spin texture develops across the cloud, which drives diffusive spin currents. Spin transport is described with two coefficients: D0⊥, the transverse spin diffusivity, and γ, the Leggett-Rice parameter. Diffusion is a dissipative effect that increases the entropy of the gas, eventually creating a mixture of spin states. γ parameterizes the rate at which spin current precesses around the local magnetization. Using a spin-echo sequence, we measure these transport parameters for a range of interaction strengths and temperatures. At unitarity, for a normal-state gas initially at one fifth of the Fermi temperature, we find D0⊥ = 2 . 3 (4) ℏ / m and γ = 1 . 08 (9) , where m is the atomic mass. In the limit of zero temperature, γ and D0⊥ are scale-invariant universal parameters of the unitary Fermi gas. The value of D0⊥ reveals strong scattering and is near its proposed quantum limit, such that the inferred value of the transport lifetime τ⊥ is comparable to ℏ /ɛF . This raises the possibility that incoherent transport may play a role. The nonzero value of γ tells us that spin waves in unitary Fermi gas are dispersive, or in other words, that the gas has a spin stiffness in the long-wavelength limit. Time permitting, we will also discuss a time-resolved measurement of the contact, through which we observe the microscopic transformation of the gas from ideal to strongly correlated.

  2. Changes in suicide rates following media reports on celebrity suicide: a meta-analysis.

    Science.gov (United States)

    Niederkrotenthaler, Thomas; Fu, King-wa; Yip, Paul S F; Fong, Daniel Y T; Stack, Steven; Cheng, Qijin; Pirkis, Jane

    2012-11-01

    A growing number of studies indicate that sensationalist reporting of suicide is associated with increases in suicide rates, but in the light of some negative findings, the issue has remained controversial. The aim of this study was to evaluate the best current evidence on the association between celebrity suicide stories and subsequent suicides. Literature searches of six data sources (Medline, Psychlit, Communication Abstracts, Education Resources Information Center, Dissertation Abstracts and Australian Public Affairs Database (APAIS)) were conducted. Studies were included if they (1) adopted an ecological design, (2) focused on celebrity suicide, (3) had completed suicide as outcome variable, (4) analysed suicide rates across all suicide methods, (5) used data from after World War II and (6) satisfied basic quality criteria. 10 studies with totally 98 suicides by celebrities met the criteria. The pooled estimate indicated a change in suicide rates (suicides per 100 000 population) of 0.26 (95% CI 0.09 to 0.43) in the month after a celebrity suicide. There was substantial heterogeneity between studies, which was explained by the type of celebrity (entertainment elite vs others) and the region of study, as indicated by mixed-effects meta-regression. The region-of-study-specific effect of reporting a suicide by an entertainment celebrity was 0.64 (95% CI 0.55 to 0.73) in North America, 0.58 (95% CI 0.47 to 0.68) in Asia, 0.36 (95% CI -0.10 to 0.61) in Australia and 0.68 (95% CI 0.51 to 0.85) in Europe. There was no indication of publication bias. Reports on celebrity suicide are associated with increases in suicides. Study region and celebrity type appear to have an impact on the effect size.

  3. Ictal heart rate changes and the effects of vagus nerve stimulation for patients with refractory epilepsy

    Directory of Open Access Journals (Sweden)

    Chen W

    2017-09-01

    Full Text Available Wei Chen,1 Fan-Gang Meng2,3 1Department of Neurology, Liaocheng People’s Hospital, Liaocheng, 2Beijing Neurosurgical Institute, Capital Medical University, 3Beijing Key Laboratory of Neuromodulation, Beijing Municipal Science and Technology Commission, Beijing, People’s Republic of China Abstract: Vagus nerve stimulation (VNS shows long-term efficiency worldwide in most pharmacoresistant patients with epilepsy; however, there are still a small number of patients who are non-responders to VNS therapy. It has been shown that VNS treatment outcomes for drug-resistant epilepsy may be predicted by preoperative heart-rate variability measurements and that patients with epilepsy with ictal tachycardia (IT during seizures have good responses to VNS. However, few studies have reported the efficacy of VNS in patients with epilepsy with ictal bradycardia (IB or normal heart rate (HR, and none have explored the possible mechanisms of VNS efficacy based on different HR types. HR during seizures varies, and we presume that different HRs during seizures may impact the effects of VNS. It has been shown that blood pressure in the human body needs to be maintained through the arterial baroreflex (ABR. VNS efficacy in patients with epilepsy with IT, IB, and normal HR during seizures may be related to ABR. Mechanical signals generated by VNS are similar to the autonomic nerve pathways and, thus, we propose the hypothesis that different HRs during seizures can predict VNS efficacy in patients. If VNS is highly efficient in patients with IT during seizures, VNS in patients with a normal HR during seizures may be less efficient, and may even be inefficient in patients with IB during seizures. Keywords: heart rate changes, VNS efficacy, refractory epilepsy 

  4. Cerebral Hemodynamic and White Matter Changes of Type 2 Diabetes Revealed by Multi-TI Arterial Spin Labeling and Double Inversion Recovery Sequence

    Directory of Open Access Journals (Sweden)

    Yelong Shen

    2017-12-01

    Full Text Available Diabetes has been reported to affect the microvasculature and lead to cerebral small vessel disease (SVD. Past studies using arterial spin labeling (ASL at single post-labeling delay reported reduced cerebral blood flow (CBF in patients with type 2 diabetes. The purpose of this study was to characterize cerebral hemodynamic changes of type 2 diabetes using a multi-inversion-time 3D GRASE pulsed ASL (PASL sequence to simultaneously measure CBF and bolus arrival time (BAT. Thirty-six patients with type 2 diabetes (43–71 years, 17 male and 36 gender- and age-matched control subjects underwent MRI scans at 3 T. Mean CBF/BAT values were computed for gray and white matter (GM and WM of each subject, while a voxel-wise analysis was performed for comparison of regional CBF and BAT between the two groups. In addition, white matter hyperintensities (WMHs were detected by a double inversion recovery (DIR sequence with relatively high sensitivity and spatial resolution. Mean CBF of the WM, but not GM, of the diabetes group was significantly lower than that of the control group (p < 0.0001. Regional CBF decreases were detected in the left middle occipital gyrus (p = 0.0075, but failed to reach significance after correction of partial volume effects. BAT increases were observed in the right calcarine fissure (p < 0.0001, left middle occipital gyrus (p < 0.0001, and right middle occipital gyrus (p = 0.0011. Within the group of diabetic patients, BAT in the right middle occipital gyrus was positively correlated with the disease duration (r = 0.501, p = 0.002, BAT in the left middle occipital gyrus was negatively correlated with the binocular visual acuity (r = −0.408, p = 0.014. Diabetic patients also had more WMHs than the control group (p = 0.0039. Significant differences in CBF, BAT, and more WMHs were observed in patients with diabetes, which may be related to impaired vision and risk of SVD of type 2 diabetes.

  5. Effects of the particle spin polarisation on the unstable modes in the ...

    Indian Academy of Sciences (India)

    . In this article, the contribution of the electron spin on the growth rate of the temperature anisotropy of electromagnetic instabilities has been investigated. Results show that polarisation of the electron spin will restrict the instability growth rate ...

  6. Nonlinear Methods to Assess Changes in Heart Rate Variability in Type 2 Diabetic Patients

    International Nuclear Information System (INIS)

    Bhaskar, Roy; Ghatak, Sobhendu

    2013-01-01

    Heart rate variability (HRV) is an important indicator of autonomic modulation of cardiovascular function. Diabetes can alter cardiac autonomic modulation by damaging afferent inputs, thereby increasing the risk of cardiovascular disease. We applied nonlinear analytical methods to identify parameters associated with HRV that are indicative of changes in autonomic modulation of heart function in diabetic patients. We analyzed differences in HRV patterns between diabetic and age-matched healthy control subjects using nonlinear methods. Lagged Poincaré plot, autocorrelation, and detrended fluctuation analysis were applied to analyze HRV in electrocardiography (ECG) recordings. Lagged Poincare plot analysis revealed significant changes in some parameters, suggestive of decreased parasympathetic modulation. The detrended fluctuation exponent derived from long-term fitting was higher than the short-term one in the diabetic population, which was also consistent with decreased parasympathetic input. The autocorrelation function of the deviation of inter-beat intervals exhibited a highly correlated pattern in the diabetic group compared with the control group. The HRV pattern significantly differs between diabetic patients and healthy subjects. All three statistical methods employed in the study may prove useful to detect the onset and extent of autonomic neuropathy in diabetic patients

  7. Application of the constant rate of pressure change method to improve jet pump performance

    International Nuclear Information System (INIS)

    Long, X P; Yang, X L

    2012-01-01

    This paper adopts a new method named the constant rate of pressure change (CRPC) to improve the jet pump performance. The main contribution of this method is that the diffuser generates uniform pressure gradient. The performance of the jet pump with new diffusers designed by the CRPC method, obtained by CFD methods, was compared with that of the jet pump with traditional conical diffusers. It is found that the CRPC diffuser produces a linear pressure increase indeed. The higher friction loss and the separation decrease the CRPC diffuser efficiency and then lower the pump efficiency. The pump with shorter throats has higher efficiency at small flow ratio while its efficiency is lower than the original pump at lager flow ratio and the peak efficiency of the pumps with the throat length of 5-6 Dt is higher than that of the pumps with other throat length. When the throat length is less than 4 Dt, the CRPC diffuser efficiency is higher than the conical diffuser. The CRPC method could also be used to design the nozzle and other situations needing the pressure change gradually.

  8. Increasing urban community empowerment through changing of poverty rate index on the productive zakat impact

    Science.gov (United States)

    Zaenal, M. H.; Astuti, A. D.; Sadariyah, A. S.

    2018-01-01

    We show how changes in poverty measures can be applied into growth of islamic philanthropy distribution via zakat, and we use the methodology to zakat community development (ZCD) program in Bantul during the 2016. The purpose of the present paper is to prove zakat is able to be a solution part for the community empowerment. The result is the number of productive zakat program beneficiaries whose income is below the poverty line (poor category) before the program are 244 people (H = 0.171) and after the program change to 168 (H = 0.118), which means the program has succeeded in reducing the number of poor people by 76 people (5.34 percent). The poverty gap (P1) of beneficiaries of productive zakat program in Bantul also decrease. The gap between poverty line and average income of beneficiaries is Rp 63,763 before the program, while the gap after the program is Rp 56,992. The income gap (I) is also decline from 0.197 to 0.169. Poverty severity of beneficiaries of productive zakat program in Bantul seen by Sen Index (P2) decrease from 0.093 to 0.062, while using Foster-Greer-Thorbecke Index (P3), the poverty severity decrease from 0.010 to 0.004. The analysis revealed the zakat community empowerment was significant economically in suppressing the poverty rate, and possible for reducing inequality and ending poverty in Indonesia.

  9. Heart rate variability changes during and after the practice of bhramari pranayama

    Directory of Open Access Journals (Sweden)

    L Nivethitha

    2017-01-01

    Full Text Available Background: Yoga is an ancient Indian science as well as the way of life. Pranayama is one of the most important yogic practices. Bhramari pranayama was shown to produce a reduction in blood pressure after the practice and thus reported to produce parasympathetic activity. However, there are no known studies reported the heart rate variability (HRV changes either during or after the practice of Bhramari. Hence, this study aims at evaluating the HRV changes during and after the practice. Materials and Methods: Sixteen (9 males, 7 females healthy volunteers with the mean ± standard deviation age of 23.50 ± 3.01 years were recruited. All the subjects performed Bhramari pranayama for the duration of 5 min. Assessments were taken before, during, and immediately after the practice of pranayama. Statistical analysis was performed using students paired samples t-test, Wilcoxon signed-ranks test and repeated measures of analysis of variance and Post-hoc analysis with Bonferroni adjustment for multiple comparisons. Results: Results of this study showed a significant increase in HR and low frequency spectrum of HRV and a significant reduction in high frequency spectrum of HRV during the practice of Bhramari which revert to normal after the practice. Conclusion: Results of this study suggests that there might be a parasympathetic withdrawal during the practice of Bhramari. However, further studies are required to warrant the findings of this study.

  10. Nonlinear Methods to Assess Changes in Heart Rate Variability in Type 2 Diabetic Patients

    Energy Technology Data Exchange (ETDEWEB)

    Bhaskar, Roy, E-mail: imbhaskarall@gmail.com [Indian Institute of Technology (India); University of Connecticut, Farmington, CT (United States); Ghatak, Sobhendu [Indian Institute of Technology (India)

    2013-10-15

    Heart rate variability (HRV) is an important indicator of autonomic modulation of cardiovascular function. Diabetes can alter cardiac autonomic modulation by damaging afferent inputs, thereby increasing the risk of cardiovascular disease. We applied nonlinear analytical methods to identify parameters associated with HRV that are indicative of changes in autonomic modulation of heart function in diabetic patients. We analyzed differences in HRV patterns between diabetic and age-matched healthy control subjects using nonlinear methods. Lagged Poincaré plot, autocorrelation, and detrended fluctuation analysis were applied to analyze HRV in electrocardiography (ECG) recordings. Lagged Poincare plot analysis revealed significant changes in some parameters, suggestive of decreased parasympathetic modulation. The detrended fluctuation exponent derived from long-term fitting was higher than the short-term one in the diabetic population, which was also consistent with decreased parasympathetic input. The autocorrelation function of the deviation of inter-beat intervals exhibited a highly correlated pattern in the diabetic group compared with the control group. The HRV pattern significantly differs between diabetic patients and healthy subjects. All three statistical methods employed in the study may prove useful to detect the onset and extent of autonomic neuropathy in diabetic patients.

  11. The fast spin of near-Earth asteroid (455213) 2001 OE84, revisited after 14 years: Constraints on internal structure

    Science.gov (United States)

    Polishook, D.; Moskovitz, N.; Thirouin, A.; Bosh, A.; Levine, S.; Zuluaga, C.; Tegler, S. C.; Aharonson, O.

    2017-11-01

    At a mean diameter of ∼650 m, the near-Earth asteroid (455213) 2001 OE84 (OE84 for short) has a rapid rotation period of 0.486542 ± 0.000002 h, which is uncommon for asteroids larger than ∼200 m. We revisited OE84 14 years after it was first, and last, observed by Pravec et al. (2002) in order to measure again its spin rate and to search for changes. We have confirmed the rapid rotation and, by fitting the photometric data from 2001 and 2016 using the lightcurve inversion technique, we determined a retrograde sense of rotation, with the spin axis close to the ecliptic south pole; an oblate shape model of a / b = 1.32 ± 0.04 and b / c = 1.8 ± 0.2 ; and no change in spin rate between 2001 and 2016. Using these parameters we constrained the body's internal strength, and found that current estimations of asteroid cohesion (up to ∼80 Pa) are insufficient to maintain an intact rubble pile at the measured spin rate of OE84. Therefore, we argue that a monolithic asteroid, that can rotate at the rate of OE84 without shedding mass and without slowing down its spin rate, is the most plausible for OE84, and we give constraints on its age, since the time it was liberated from its parent body, between 2 - 10 million years.

  12. Exposure to Fine Particulate Matter Leads to Rapid Heart Rate Variability Changes

    Directory of Open Access Journals (Sweden)

    Michael Riediker

    2018-01-01

    Full Text Available Introduction: Heart Rate Variability (HRV reflects the adaptability of the heart to internal and external stimuli. Reduced HRV is a predictor of post-infarction mortality. We previously found in road maintenance workers HRV-increases several hours after exposure to fine particulate matter (PM2.5. This seemed to conflict with studies where PM-exposure acutely reduced HRV. We therefore assessed whether time from exposure to HRV-assessment could explain the differences observed.Methods: On five non-consecutive days, workers carried nephelometers providing 1-min-interval PM2.5-exposure. Five-min HRV-intervals of SDNN (Standard Deviation of Normal to Normal beat intervals and pNN50 (Percentage of the interval differences exceeding 50 ms were extracted from 24-h electrocardiograms (ECGs. Following 60 min PM2.5-exposure, changes in HRV-parameters were assessed during 120-min visually and by regression analysis with control for time at work, at home, and during the night using autoregressive integrating moving average (ARIMA models to account for autocorrelation of the time-series. Additional controls included changing the time windows and including body mass index (BMI and age in the models.Result: Pattern analysis of 12,669 data points showed high modulation of mean, standard deviation (SD, and time trend of HRV (SDNN and pNN50 at low, and much reduced modulation at high PM2.5-exposures. The time trend following exposure was highly symmetrical, resembling a funnel plot. Regression analysis showed significant associations of decreasing SDNN and pNN50 (average, SD, and absolute value of time trend with increasing PM2.5-exposure, which remained significant when controlling for activity phases. Changing time windows did not change the pattern of response. Including BMI and age did not change the results.Conclusions: The reduced modulation of HRV following PM2.5-exposure is striking. It suggests strong interference with homeostatic controls. Such an

  13. Phase transitions and thermal entanglement of the distorted Ising-Heisenberg spin chain: topology of multiple-spin exchange interactions in spin ladders

    Science.gov (United States)

    Arian Zad, Hamid; Ananikian, Nerses

    2017-11-01

    We consider a symmetric spin-1/2 Ising-XXZ double sawtooth spin ladder obtained from distorting a spin chain, with the XXZ interaction between the interstitial Heisenberg dimers (which are connected to the spins based on the legs via an Ising-type interaction), the Ising coupling between nearest-neighbor spins of the legs and rungs spins, respectively, and additional cyclic four-spin exchange (ring exchange) in the square plaquette of each block. The presented analysis supplemented by results of the exact solution of the model with infinite periodic boundary implies a rich ground state phase diagram. As well as the quantum phase transitions, the characteristics of some of the thermodynamic parameters such as heat capacity, magnetization and magnetic susceptibility are investigated. We prove here that among the considered thermodynamic and thermal parameters, solely heat capacity is sensitive versus the changes of the cyclic four-spin exchange interaction. By using the heat capacity function, we obtain a singularity relation between the cyclic four-spin exchange interaction and the exchange coupling between pair spins on each rung of the spin ladder. All thermal and thermodynamic quantities under consideration should be investigated by regarding those points which satisfy the singularity relation. The thermal entanglement within the Heisenberg spin dimers is investigated by using the concurrence, which is calculated from a relevant reduced density operator in the thermodynamic limit.

  14. Study of supersonic flow in a constant rate of momentum change (CRMC) ejector with frictional effects

    International Nuclear Information System (INIS)

    Kumar, Virendra; Singhal, Gaurav; Subbarao, P.M.V.

    2013-01-01

    The constant rate of momentum change (CRMC) is a new approach towards design of supersonic ejectors. CRMC methodology was first proposed by Eames [1] in a study which was primarily based on isentropic flow inside the diffusing region of a supersonic ejector. The prime benefit that accrues from employing a CRMC ejector is that it can effectively eliminate the irreversibility associated with occurrence of thermodynamic shock process. The present study examines the supersonic flow in a CRMC ejector from the perspective of an adiabatic flow with frictional effects inside the variable cross-section of supersonic ejector, which is apparently more realistic. An analytical model has been discussed for the prediction of flow parameter variation in a space marching formulation taking into account change in localized frictional coefficient due to corresponding changes at each step. The analytical results have been validated by conducting a computational study based on 2-D axi-symmetric viscous compressible flow formulation with turbulence in FLUENT. The results are in good agreement at on-design conditions. The predictions especially for the recovered pressure made through the analytical formulation incorporating friction are found to be in significantly better agreement than the isentropic approach. The experimental validation for the approach has also been presented with the results being in close agreement with analytically predicted values. -- Highlights: • CRMC ejector eliminates the irreversibility due to occurrence of thermodynamic shock. • Frictional effect based apparently present more realistic solution for ejector. • Static pressure variation between proposed model and numerical study is nearly 2.29%. • Static pressure variation between analytical and experimental values is nearly 4%. • Experimentally observed entrainment ratio shows 3% variation w.r.t. design point value

  15. Fractional Spin Fluctuations as a Precursor of Quantum Spin Liquids: Majorana Dynamical Mean-Field Study for the Kitaev Model.

    Science.gov (United States)

    Yoshitake, Junki; Nasu, Joji; Motome, Yukitoshi

    2016-10-07

    Experimental identification of quantum spin liquids remains a challenge, as the pristine nature is to be seen in asymptotically low temperatures. We here theoretically show that the precursor of quantum spin liquids appears in the spin dynamics in the paramagnetic state over a wide temperature range. Using the cluster dynamical mean-field theory and the continuous-time quantum Monte Carlo method, which are newly developed in the Majorana fermion representation, we calculate the dynamical spin structure factor, relaxation rate in nuclear magnetic resonance, and magnetic susceptibility for the honeycomb Kitaev model whose ground state is a canonical example of the quantum spin liquid. We find that dynamical spin correlations show peculiar temperature and frequency dependence even below the temperature where static correlations saturate. The results provide the experimentally accessible symptoms of the fluctuating fractionalized spins evincing the quantum spin liquids.

  16. Spin physics in semiconductors

    CERN Document Server

    2017-01-01

    This book offers an extensive introduction to the extremely rich and intriguing field of spin-related phenomena in semiconductors. In this second edition, all chapters have been updated to include the latest experimental and theoretical research. Furthermore, it covers the entire field: bulk semiconductors, two-dimensional semiconductor structures, quantum dots, optical and electric effects, spin-related effects, electron-nuclei spin interactions, Spin Hall effect, spin torques, etc. Thanks to its self-contained style, the book is ideally suited for graduate students and researchers new to the field.

  17. Oxygen in the deep-sea: The challenge of maintaining uptake rates in a changing ocean

    Science.gov (United States)

    Hofmann, A. F.; Peltzer, E. T.; Brewer, P. G.

    2011-12-01

    Although focused on recently, ocean acidification is not the only effect of anthropogenic CO2 emissions on the ocean. Ocean warming will reduce dissolved oxygen concentrations and at the hypoxic limit for a given species this can pose challenges to marine life. The limit is traditionally reported simply as the static mass concentration property [O2]; here we treat it as a dynamic gas exchange problem for the animal analogous to gas exchange at the sea surface. The diffusive limit and its relationship to water velocity is critical for the earliest stages of marine life (eggs, embryos), but the effect is present for all animals at all stages of life. We calculate the external limiting O2 conditions for several representative metabolic rates and their relationship to flow of the bulk fluid under different environmental conditions. Ocean O2 concentrations decline by ≈ 14 μmol kg-1 for a 2 °C rise in temperature. At standard 1000 m depth conditions in the Pacific, flow over the surface would have to increase by ≈ 60% from 2.0 to 3.2 cm s-1 to compensate for this change. The functions derived allow new calculations of depth profiles of limiting O2 concentrations, as well as maximal diffusively sustainable metabolic oxygen consumption rates at various places around the world. Our treatment shows that there is a large variability in the global ocean in terms of facilitating aerobic life. This variability is greater than the variability of the oxygen concentration alone. It becomes clear that temperature and pressure dependencies of diffusion and partial pressure create a region typically around 1000 m depth where a maximal [O2] is needed to sustain a given metabolic rate. This zone of greatest physical constriction on the diffusive transport in the boundary layer is broadly consistent with the oxygen minimum zone, i.e., the zone of least oxygen concentration supply, resulting in a pronounced minimum of maximal diffusively sustainable metabolic oxygen consumption

  18. A Conceptual Model for Projecting Coccolithophorid Growth, Calcification and Photosynthetic Carbon Fixation Rates in Response to Global Ocean Change

    Directory of Open Access Journals (Sweden)

    Natasha A. Gafar

    2018-01-01

    Full Text Available Temperature, light and carbonate chemistry all influence the growth, calcification and photosynthetic rates of coccolithophores to a similar degree. There have been multiple attempts to project the responses of coccolithophores to changes in carbonate chemistry, but the interaction with light and temperature remains elusive. Here we devise a simple conceptual model to derive a fit equation for coccolithophorid growth, photosynthetic and calcification rates in response to simultaneous changes in carbonate chemistry, temperature and light conditions. The fit equation is able to account for up to 88% of the variability in measured metabolic rates. Equation projections indicate that temperature, light and carbonate chemistry all have different modulating effects on both optimal growth conditions and the sensitivity of responses to extreme environmental conditions. Calculations suggest that a single extreme environmental condition (CO2, temperature, light will reduce maximum rates regardless of how optimal the other environmental conditions may be. Thus, while the response of coccolithophores to ocean change depends on multiple variables, the one which is least optimal will have the most impact on overall rates. Finally, responses to ocean change are usually reported in terms of cellular rates. However, changes in cellular rates can be a poor predictor for assessing changes in production at the community level. We therefore introduce a new metric, the calcium carbonate production potential (CCPP, which combines the independent effects of changes in growth rate and cellular calcium carbonate content to assess how environmental changes will impact coccolith production. Direct comparison of CO2 impacts on cellular CaCO3 production rates and CCPP shows that while the former is still at 45% of its pre-industrial capacity at 1,000 μatm, the latter is reduced to 10%.

  19. The association between changes in household firearm ownership and rates of suicide in the United States, 1981-2002.

    Science.gov (United States)

    Miller, M; Azrael, D; Hepburn, L; Hemenway, D; Lippmann, S J

    2006-06-01

    To explore whether recent declines in household firearm prevalence in the United States were associated with changes in rates of suicide for men, women, and children. This time series study compares changes in suicide rates to changes in household firearm prevalence, 1981-2002. Multivariate analyses adjust for age, unemployment, per capita alcohol consumption, and poverty. Regional fixed effects controlled for cross sectional, time invariant differences among the four census regions. Standard errors of parameter estimates are adjusted to account for serial autocorrelation of observations over time. Over the 22 year study period household firearm ownership rates declined across all four regions. In multivariate analyses, each 10% decline in household firearm ownership was associated with significant declines in rates of firearm suicide, 4.2% (95% CI 2.3% to 6.1%) and overall suicide, 2.5% (95% CI 1.4% to 3.6%). Changes in non-firearm suicide were not associated with changes in firearm ownership. The magnitude of the association between changes in household firearm ownership and changes in rates of firearm and overall suicide was greatest for children: for each 10% decline in the percentage of households with firearms and children, the rate of firearm suicide among children 0-19 years of age dropped 8.3% (95% CI 6.1% to 10.5%) and the rate of overall suicide dropped 4.1% (2.3% to 5.9%). Changes in household firearm ownership over time are associated with significant changes in rates of suicide for men, women, and children. These findings suggest that reducing availability to firearms in the home may save lives, especially among youth.

  20. The association between changes in household firearm ownership and rates of suicide in the United States, 1981–2002

    Science.gov (United States)

    Miller, M; Azrael, D; Hepburn, L; Hemenway, D; Lippmann, S J

    2006-01-01

    Objective To explore whether recent declines in household firearm prevalence in the United States were associated with changes in rates of suicide for men, women, and children. Methods This time series study compares changes in suicide rates to changes in household firearm prevalence, 1981–2002. Multivariate analyses adjust for age, unemployment, per capita alcohol consumption, and poverty. Regional fixed effects controlled for cross sectional, time invariant differences among the four census regions. Standard errors of parameter estimates are adjusted to account for serial autocorrelation of observations over time. Results Over the 22 year study period household firearm ownership rates declined across all four regions. In multivariate analyses, each 10% decline in household firearm ownership was associated with significant declines in rates of firearm suicide, 4.2% (95% CI 2.3% to 6.1%) and overall suicide, 2.5% (95% CI 1.4% to 3.6%). Changes in non‐firearm suicide were not associated with changes in firearm ownership. The magnitude of the association between changes in household firearm ownership and changes in rates of firearm and overall suicide was greatest for children: for each 10% decline in the percentage of households with firearms and children, the rate of firearm suicide among children 0–19 years of age dropped 8.3% (95% CI 6.1% to 10.5%) and the rate of overall suicide dropped 4.1% (2.3% to 5.9%). Conclusion Changes in household firearm ownership over time are associated with significant changes in rates of suicide for men, women, and children. These findings suggest that reducing availability to firearms in the home may save lives, especially among youth. PMID:16751449

  1. Dynamic evolutionary change in post-Paleozoic echinoids and the importance of scale when interpreting changes in rates of evolution.

    Science.gov (United States)

    Hopkins, Melanie J; Smith, Andrew B

    2015-03-24

    How ecological and morphological diversity accrues over geological time has been much debated by paleobiologists. Evidence from the fossil record suggests that many clades reach maximal diversity early in their evolutionary history, followed by a decline in evolutionary rates as ecological space fills or due to internal constraints. Here, we apply recently developed methods for estimating rates of morphological evolution during the post-Paleozoic history of a major invertebrate clade, the Echinoidea. Contrary to expectation, rates of evolution were lowest during the initial phase of diversification following the Permo-Triassic mass extinction and increased over time. Furthermore, although several subclades show high initial rates and net decreases in rates of evolution, consistent with "early bursts" of morphological diversification, at more inclusive taxonomic levels, these bursts appear as episodic peaks. Peak rates coincided with major shifts in ecological morphology, primarily associated with innovations in feeding strategies. Despite having similar numbers of species in today's oceans, regular echinoids have accrued far less morphological diversity than irregular echinoids due to lower intrinsic rates of morphological evolution and less morphological innovation, the latter indicative of constrained or bounded evolution. These results indicate that rates of evolution are extremely heterogenous through time and their interpretation depends on the temporal and taxonomic scale of analysis.

  2. Spin transport in two-layer-CVD-hBN/graphene/hBN heterostructures

    Science.gov (United States)

    Gurram, M.; Omar, S.; Zihlmann, S.; Makk, P.; Li, Q. C.; Zhang, Y. F.; Schönenberger, C.; van Wees, B. J.

    2018-01-01

    We study room-temperature spin transport in graphene devices encapsulated between a layer-by-layer-stacked two-layer-thick chemical vapor deposition (CVD) grown hexagonal boron nitride (hBN) tunnel barrier, and a few-layer-thick exfoliated-hBN substrate. We find mobilities and spin-relaxation times comparable to that of SiO2 substrate-based graphene devices, and we obtain a similar order of magnitude of spin relaxation rates for both the Elliott-Yafet and D'Yakonov-Perel' mechanisms. The behavior of ferromagnet/two-layer-CVD-hBN/graphene/hBN contacts ranges from transparent to tunneling due to inhomogeneities in the CVD-hBN barriers. Surprisingly, we find both positive and negative spin polarizations for high-resistance two-layer-CVD-hBN barrier contacts with respect to the low-resistance contacts. Furthermore, we find that the differential spin-injection polarization of the high-resistance contacts can be modulated by dc bias from -0.3 to +0.3 V with no change in its sign, while its magnitude increases at higher negative bias. These features point to the distinctive spin-injection nature of the two-layer-CVD-hBN compared to the bilayer-exfoliated-hBN tunnel barriers.

  3. Physiological, biochemical and productive changes in sesame genotypes subjected to different rates of water replenishment

    Directory of Open Access Journals (Sweden)

    Maria S. R. Lima

    Full Text Available ABSTRACT The sesame crop has stood out due to the high nutritional content of its seeds, in addition to being able to be cultivated in the tropical and subtropical regions such as Northeast Brazil. Thus, it is necessary to identify the physiological, biochemical and productive changes related to the tolerance to stress. Objective of this study was to evaluate the physiological, biochemical and productive aspects of sesame genotypes as a function of different rates of water replenishment. The experiment was carried out at the Embrapa Cotton Experimental Unit, located in the municipality of Barbalha-CE, Brazil, under field conditions. The experiment was carried out in a randomized complete block design, with treatments in a factorial scheme (4 × 6, corresponding to four irrigation depths (40, 70, 100 and 130% ETo and six sesame genotypes (G1 = T3-EGSGO3; G2 = T7-EGSGO7; G3 = T5-EGSGO5; G4 = T2-EGSGO2; G5 = T6-EGSGO6; G6 = T4-EGSG04, with three replicates. Data corresponding to the following variables were collected: leaf area, photosynthetic pigments, relative water content in leaf, electrolyte leakage, catalase, peroxidase, yield and oil content. The genotypes did not differ statistically and there were differences in the variables between the water replacement rates. Increments in growth and, consequently, in production, enzymatic activity, oil content and maximum production potential were observed with water depths between 75 and 90% ETo. Contents of chlorophyll a and b, total chlorophyll and carotenoids, were increased with the application of 80% ETo.

  4. The relation between gravity rate of change and vertical displacement in previously glaciated areas

    Science.gov (United States)

    Olsson, Per-Anders; Milne, Glenn; Scherneck, Hans-Georg; Ågren, Jonas

    2015-01-01

    The rate of change of surface gravity, g˙, and vertical deformation rate of the solid surface, u˙, are two observables of glacial isostatic adjustment (GIA). They contribute with different information on the same phenomenon. Their relation contains information of the underlying physics and a trustworthy relation allows to combine these observations to strengthen the overall observational accuracy of the phenomenon. In this paper we investigate the predicted relation between g˙ and u˙ in previously glaciated areas. We use the normal mode approach for one dimensional earth models and solutions of the sea level equation with time-dependent coastline geometry. Numerical predictions of g˙ and u˙ are computed for Laurentia, Fennoscandia and the British Isles respectively, using six different earth models. Within each region a linear trend is then fitted using the relation g˙ = Cu˙ +g˙0. The estimated C and g˙0 differ more between the regions than between different earth models within each region. For Fennoscandia C ≈ -0.163 μGal/mm and for Laurentia C ≈ -0.152 μGal/mm. Maximum residuals between the linear trend and spatially varying model predictions of g˙ are 0.04 μGal/yr in Fennoscandia and 0.17 μGal/yr in Laurentia. For the British Isles the results are harder to interpret, mainly since this region is located on the zero uplift isoline of Fennoscandia. In addition, we show temporal variation of the relation since the last glacial maximum till present-day. The temporal and spatial variation of the relation between g˙ and u˙ can be explained by (i) the elastic respectively viscous proportion of the total signal and (ii) the spectral composition of the regional signal. Additional local effects, such as the Newtonian attraction and elastic deformation from local sea level changes, are examined in a case study for six stations in the Nordic absolute gravity network. The influence of these local effects on the relation between g˙ and u˙ is negligible

  5. Robust temperature change rate actuated valving and switching for highly integrated centrifugal microfluidics.

    Science.gov (United States)

    Keller, M; Czilwik, G; Schott, J; Schwarz, I; Dormanns, K; von Stetten, F; Zengerle, R; Paust, N

    2017-02-28

    We present new unit operations for valving and switching in centrifugal microfluidics that are actuated by a temperature change rate (TCR) and controlled by the rotational frequency. Implementation is realized simply by introducing a comparatively large fluidic resistance to an air vent of a fluidic structure downstream of a siphon channel. During temperature decrease at a given TCR, the air pressure inside the downstream structure decreases and the fluidic resistance of the air vent slows down air pressure compensation allowing a thermally induced underpressure to build up temporarily. Thereby the rate of temperature change determines the time course of the underpressure for a given geometry. The thermally induced underpressure pulls the liquid against a centrifugal counterpressure above a siphon crest, which triggers the valve or switch. The centrifugal counterpressure (adjusted by rotation) serves as an independent control parameter to allow or prevent valving or switching at any TCR. The unit operations are thus compatible with any temperature or centrifugation protocol prior to valving or switching. In contrast to existing methods, this compatibility is achieved at no additional costs: neither additional fabrication steps nor additional disk space or external means are required besides global temperature control, which is needed for the assay. For the layout, an analytical model is provided and verified. The TCR actuated unit operations are demonstrated, first, by a stand-alone switch that routes the liquid to either one of the two collection chambers (n = 6) and, second, by studying the robustness of TCR actuated valving within a microfluidic cartridge for highly integrated nucleic acid testing. Valving could safely be prevented during PCR by compensating the thermally induced underpressure of 3.52 kPa with a centrifugal counterpressure at a rotational frequency of 30 Hz with a minimum safety range to valving of 2.03 kPa. Subsequently, a thermally induced

  6. New England observed and predicted July maximum negative stream/river temperature daily rate of change points

    Data.gov (United States)

    U.S. Environmental Protection Agency — The shapefile contains points with associated observed and predicted July stream/river temperature maximum negative daily rate of change in New England based on a...

  7. New England observed and predicted July stream/river temperature maximum positive daily rate of change points

    Data.gov (United States)

    U.S. Environmental Protection Agency — The shapefile contains points with associated observed and predicted July stream/river temperature maximum positive daily rate of change in New England based on a...

  8. New England observed and predicted August stream/river temperature maximum positive daily rate of change points

    Data.gov (United States)

    U.S. Environmental Protection Agency — The shapefile contains points with associated observed and predicted August stream/river temperature maximum positive daily rate of change in New England based on a...

  9. The effect of the melting spinning cooling rate on transformation temperatures in ribbons Ti-Ni-Cu shape memory; Efeito da taxa de resfriamento nas temperaturas de transformacao de uma liga Ni-Cu-Ti com efeito de memoria de forma solidificadas rapidamente

    Energy Technology Data Exchange (ETDEWEB)

    Ramos, A.P.; Castro, W.B.; Anselmo, G.C. dos S., E-mail: walman@dem.ufcg.edu.br [Universidade Federal de Campina Grande (UFCG), PB (Brazil)

    2014-07-01

    Ti-Ni-Cu alloys have been attracting attention by their high performance of shape memory effect and decrease of thermal and stress hysteresis in comparison with Ti-Ni binary alloys. One important challenge of microsystems design is the implementation of miniaturized actuation principles efficient at the micro-scale. Shape memory alloys (SMAs) have early on been considered as a potential solution to this problem as these materials offer attractive properties like a high-power to weight ratio, large deformation and the capability to be processed at the micro-scale. Shape memory characteristics of Ti-37,8Cu-18,7Ni alloy ribbons prepared by melt spinning were investigated by means of differential scanning calorimetry and X-ray diffraction. In these experiments particular attention has been paid to change of the velocity of cooling wheel from 21 to 63 m/s. Then the cooling rates of ribbons were controlled. The effect of this cooling rate on austenitic and martensitic transformations behaviors is discussed. (author)

  10. Barometric pressure change and heart rate response during sleeping at 3000 m altitude

    Science.gov (United States)

    Horiuchi, Masahiro; Endo, Junko; Handa, Yoko; Nose, Hiroshi

    2017-12-01

    We investigated effects of change in barometric pressure (P B) with climate change on heart rate (HR) during sleep at 3000 m altitude. Nineteen healthy adults (15 males and four females; mean age 32 years) participated in this study. We measured P B (barometry) and HR (electrocardiography) every minute during their overnight stay in a mountain lodge at 3000 m. We also measured resting arterial oxygen saturation (SpO2) and evaluated symptoms of acute mountain sickness (AMS) by using the Lake Louise Questionnaire at 2305 and 3000 m, respectively. P B gradually decreased during the night at the speed of approximately - 0.5 hPa/h. We found that HR during sleep decreased linearly as P B decreased in all subjects, with significance (r = 0.492-0.893; all, P < 0.001). Moreover, cross correlation analysis revealed that HR started to decrease after 15 min following the decrease in P B, on average. SpO2 was 93.8 ± 1.7% at 2305 m before climbing, then decreased significantly to 90.2 ± 2.2% at the lodge before going to bed, and further decreased to 87.5 ± 2.7% after waking (all, P < 0.05). Four of the 19 subjects showed a symptom of AMS after waking (21%). Further, the decrease in HR in response to a given decrease in P B (ΔHR/ΔPB) was negatively related with a decrease in SpO2 from before going to bed to after waking at 3000 m (r = - 0.579, P = 0.009) and with total AMS scores after waking (r = 0.489, P = 0.033).

  11. Impacts of aerosol direct effects on tropospheric ozone through changes in atmospheric dynamics and photolysis rates

    Science.gov (United States)

    Xing, Jia; Wang, Jiandong; Mathur, Rohit; Wang, Shuxiao; Sarwar, Golam; Pleim, Jonathan; Hogrefe, Christian; Zhang, Yuqiang; Jiang, Jingkun; Wong, David C.; Hao, Jiming

    2017-08-01

    Aerosol direct effects (ADEs), i.e., scattering and absorption of incoming solar radiation, reduce radiation reaching the ground and the resultant photolysis attenuation can decrease ozone (O3) formation in polluted areas. One the other hand, evidence also suggests that ADE-associated cooling suppresses atmospheric ventilation, thereby enhancing surface-level O3. Assessment of ADE impacts is thus important for understanding emission reduction strategies that seek co-benefits associated with reductions in both particulate matter and O3 levels. This study quantifies the impacts of ADEs on tropospheric ozone by using a two-way online coupled meteorology and atmospheric chemistry model, WRF-CMAQ, using a process analysis methodology. Two manifestations of ADE impacts on O3 including changes in atmospheric dynamics (ΔDynamics) and changes in photolysis rates (ΔPhotolysis) were assessed separately through multiple scenario simulations for January and July of 2013 over China. Results suggest that ADEs reduced surface daily maxima 1 h O3 (DM1O3) in China by up to 39 µg m-3 through the combination of ΔDynamics and ΔPhotolysis in January but enhanced surface DM1O3 by up to 4 µg m-3 in July. Increased O3 in July is largely attributed to ΔDynamics, which causes a weaker O3 sink of dry deposition and a stronger O3 source of photochemistry due to the stabilization of the atmosphere. Meanwhile, surface OH is also enhanced at noon in July, though its daytime average values are reduced in January. An increased OH chain length and a shift towards more volatile organic compound (VOC)-limited conditions are found due to ADEs in both January and July. This study suggests that reducing ADEs may have the potential risk of increasing O3 in winter, but it will benefit the reduction in maxima O3 in summer.

  12. Association of metabolic syndrome and change in Unified Parkinson's Disease Rating Scale scores.

    Science.gov (United States)

    Leehey, Maureen; Luo, Sheng; Sharma, Saloni; Wills, Anne-Marie A; Bainbridge, Jacquelyn L; Wong, Pei Shieen; Simon, David K; Schneider, Jay; Zhang, Yunxi; Pérez, Adriana; Dhall, Rohit; Christine, Chadwick W; Singer, Carlos; Cambi, Franca; Boyd, James T

    2017-10-24

    To explore the association between metabolic syndrome and the Unified Parkinson's Disease Rating Scale (UPDRS) scores and, secondarily, the Symbol Digit Modalities Test (SDMT). This is a secondary analysis of data from 1,022 of 1,741 participants of the National Institute of Neurological Disorders and Stroke Exploratory Clinical Trials in Parkinson Disease Long-Term Study 1, a randomized, placebo-controlled trial of creatine. Participants were categorized as having or not having metabolic syndrome on the basis of modified criteria from the National Cholesterol Education Program Adult Treatment Panel III. Those who had the same metabolic syndrome status at consecutive annual visits were included. The change in UPDRS and SDMT scores from randomization to 3 years was compared in participants with and without metabolic syndrome. Participants with metabolic syndrome (n = 396) compared to those without (n = 626) were older (mean [SD] 63.9 [8.1] vs 59.9 [9.4] years; p metabolic syndrome experienced an additional 0.6- (0.2) unit annual increase in total UPDRS ( p = 0.02) and 0.5- (0.2) unit increase in motor UPDRS ( p = 0.01) scores compared with participants without metabolic syndrome. There was no difference in the change in SDMT scores. Persons with Parkinson disease meeting modified criteria for metabolic syndrome experienced a greater increase in total UPDRS scores over time, mainly as a result of increases in motor scores, compared to those who did not. Further studies are needed to confirm this finding. NCT00449865. © 2017 American Academy of Neurology.

  13. H1N1 seasonal influenza virus evolutionary rate changed over time.

    Science.gov (United States)

    Suptawiwat, Ornpreya; Kongchanagul, Alita; Boonarkart, Chompunuch; Auewarakul, Prasert

    2018-03-30

    It was previously shown that the seasonal H1N1 influenza virus antigenic drift occurred at a slower rate than the seasonal H3N2 virus during the first decade of the 21 t h century. It was hypothesized that the slower antigenic evolution led to a decrease in average ages of infection, which in turn resulted in lower level of global viral circulation. It is unclear what caused the difference between the two viruses, but a plausible explanation may be related to the fact that the H1N1 virus had been in human population for much longer than the H3N2 virus. This would suggest that H1N1 antigenic drift in an earlier period may have been different from a more recent period. To test this hypothesis, we analyzed seasonal H1N1 influenza sequences during various time periods. In comparison to more recent H1N1 virus, the older H1N1 virus during the first half of the 20 t h century showed evidences of higher nonsynnonymous/synonymous ration (dN/dS) in its hemagglutinin (HA) gene. We compared amino acid sequence changes in the HA epitopes for each outbreak season and found that there were less changes in later years. Amino acid sequence diversity in the epitopes as measured by sequence entropy became smaller for each passing decade. These suggest that there might be some limit to the antigenic drift. The longer an influenza virus has drifted in human population, the less flexibility it may become. With less flexibility to adapt and escape the host immunity, the virus may have to rely more on younger naïve population. Copyright © 2018. Published by Elsevier B.V.

  14. Major Changes in Growth Rate and Growth Variability of Beech (Fagus sylvatica L. Related to Soil Alteration and Climate Change in Belgium

    Directory of Open Access Journals (Sweden)

    Nicolas Latte

    2016-08-01

    Full Text Available Global change—particularly climate change, forest management, and atmospheric deposition—has significantly altered forest growing conditions in Europe. The influences of these changes on beech growth (Fagus sylvatica L. were investigated for the past 80 years in Belgium, using non-linear mixed effects models on ring-width chronologies of 149 mature and dominant beech trees (87–186 years old. The effects of the developmental stage (i.e., increasing tree size were filtered out in order to focus on time-dependent growth changes. Beech radial growth was divided into a low-frequency signal (=growth rate, mainly influenced by forest management and atmospheric deposition, and into a high-frequency variability (≈mean sensitivity, mainly influenced by climate change. Between 1930 and 2008, major long-term and time-dependent changes were highlighted. The beech growth rate has decreased by about 38% since the 1950–1960s, and growth variability has increased by about 45% since the 1970–1980s. Our results indicate that (1 before the 1980s, beech growth rate was not predominantly impacted by climate change but rather by soil alteration (i.e., soil compaction and/or nitrogen deposition; and (2 since the 1980s, climate change induced more frequent and intense yearly growth reductions that amplified the growth rate decrease. The highlighted changes were similar in the two ecoregions of Belgium, although more pronounced in the lowlands than in the uplands.

  15. Changes in monthly unemployment rates may predict changes in the number of psychiatric presentations to emergency services in South Australia.

    Science.gov (United States)

    Bidargaddi, Niranjan; Bastiampillai, Tarun; Schrader, Geoffrey; Adams, Robert; Piantadosi, Cynthia; Strobel, Jörg; Tucker, Graeme; Allison, Stephen

    2015-07-24

    To determine the extent to which variations in monthly Mental Health Emergency Department (MHED) presentations in South Australian Public Hospitals are associated with the Australian Bureau of Statistics (ABS) monthly unemployment rates. Times series modelling of relationships between monthly MHED presentations to South Australian Public Hospitals derived from the Integrated South Australian Activity Collection (ISAAC) data base and the ABS monthly unemployment rates in South Australia between January 2004-June 2011. Time series modelling using monthly unemployment rates from ABS as a predictor variable explains 69% of the variation in monthly MHED presentations across public hospitals in South Australia. Thirty-two percent of the variation in current month's male MHED presentations can be predicted by using the 2 months' prior male unemployment rate. Over 63% of the variation in monthly female MHED presentations can be predicted by either male or female prior monthly unemployment rates. The findings of this study highlight that even with the relatively favourable economic conditions, small shifts in monthly unemployment rates can predict variations in monthly MHED presentations, particularly for women. Monthly ABS unemployment rates may be a useful metric for predicting demand for emergency mental health services.

  16. Tomosynthesis in the Diagnostic Setting: Changing Rates of BI-RADS Final Assessment over Time.

    Science.gov (United States)

    Raghu, Madhavi; Durand, Melissa A; Andrejeva, Liva; Goehler, Alexander; Michalski, Mark H; Geisel, Jaime L; Hooley, Regina J; Horvath, Laura J; Butler, Reni; Forman, Howard P; Philpotts, Liane E

    2016-10-01

    Purpose To evaluate the effect of tomosynthesis in diagnostic mammography on the Breast Imaging Reporting and Data System (BI-RADS) final assessment categories over time. Materials and Methods This retrospective study was approved by the institutional review board. The authors reviewed all diagnostic mammograms obtained during a 12-month interval before (two-dimensional [2D] mammography [June 2, 2010, to June 1, 2011]) and for 3 consecutive years after (tomosynthesis year 1 [2012], tomosynthesis year 2 [2013], and tomosynthesis year 3 [2014]) the implementation of tomosynthesis. The requirement to obtain informed consent was waived. The rates of BI-RADS final assessment categories 1-5 were compared between the 2D and tomosynthesis groups. The positive predictive values after biopsy (PPV3) for BI-RADS category 4 and 5 cases were compared. The mammographic features (masses, architectural distortions, calcifications, focal asymmetries) of lesions categorized as probably benign (BI-RADS category 3) and those for which biopsy was recommended (BI-RADS category 4 or 5) were reviewed. The χ(2) test was used to compare the rates of BI-RADS final assessment categories 1-5 between the two groups, and multivariate logistic regression analysis was performed to compare all diagnostic studies categorized as BI-RADS 3-5. Results There was an increase in the percentage of cases reported as negative or benign (BI-RADS category 1 or 2) with tomosynthesis (58.7% with 2D mammography vs 75.8% with tomosynthesis at year 3, P BI-RADS category 3) final assessments also occurred (33.3% with 2D mammography vs 16.4% with tomosynthesis at year 3, P BI-RADS 4 or 5 assessments did not change significantly with tomosynthesis (8.0% with 2D mammography vs 7.8% with tomosynthesis at year 3, P = .2), there was a significant increase in the PPV3 (29.6% vs 50%, respectively; P BI-RADS final assessment categories over time, with a significant increase in the proportion of studies classified as normal

  17. Muon spin relaxation in random spin systems

    International Nuclear Information System (INIS)

    Toshimitsu Yamazaki

    1981-01-01

    The longitudinal relaxation function Gsub(z)(t) of the positive muon can reflect dynamical characters of local field in a unique way even when the correlation time is longer than the Larmor period of local field. This method has been applied to studies of spin dynamics in spin glass systems, revealing sharp but continuous temperature dependence of the correlation time. Its principle and applications are reviewed. (author)

  18. Relationship between staff-reported culture change and occupancy rate and organizational commitment among nursing homes in South Korea.

    Science.gov (United States)

    Lee, Minhong; Choi, Jae-Sung; Lim, Jinseop; Kim, Young Sun

    2013-04-01

    This study aims to examine culture change in nursing homes in South Korea and to identify the outcomes of culture change implementation. Data were taken from survey responses from 223 top- or mid-level staff among nursing homes in South Korea that were selected through a proportionate random-stratified sampling method from four regions nationwide. Culture change in nursing homes was operationalized by five person-directed care (PDC) constructs and three organizational environment constructs, and outcome quality was indicated by changes to occupancy rate and organizational commitment. After controlling for facility characteristics, the effect of staff-reported culture change on occupancy rate and organizational commitment was analyzed through the multiple-regression method. Consistent with previous research, this study revealed positive effects of culture change for nursing homes in South Korea. The study found that staff-reported culture change correlated with occupancy rate and organizational commitment. Given that culture change variables were significantly related to occupancy rate and organizational commitment, the findings of the study provide a persuasive argument that policies and/or programs to support culture change in nursing homes should be enhanced. Management-level workers in these facilities should have the skills and knowledge to foster more PDC and a more person-directed environment.

  19. Spin-forming Project Report

    Energy Technology Data Exchange (ETDEWEB)

    Switzner, Nathan; Henry, Dick

    2009-03-20

    In a second development order, spin-forming equipment was again evaluated using the test shape, a hemispherical shell. In this second development order, pure vanadium and alloy titanium (Ti-6Al-4V) were spin-formed, as well as additional copper and 21-6-9 stainless. In the first development order the following materials had been spin-formed: copper (alloy C11000 ETP), 6061 aluminum, 304L stainless steel, 21-6-9 stainless steel, and tantalum-2.5% tungsten. Significant challenges included properly adjusting the rotations-per-minute (RPM), cracking at un-beveled edges and laser marks, redressing of notches, surface cracking, non-uniform temperature evolution in the titanium, and cracking of the tailstock. Lessons learned were that 300 RPM worked better than 600 RPM for most materials (at the feed rate of 800 mm/min); beveling the edges to lower the stress reduces edge cracking; notches, laser marks, or edge defects in the preform doom the process to cracking and failure; coolant is required for vanadium spin-forming; increasing the number of passes to nine or more eliminates surface cracking for vanadium; titanium develops a hot zone in front of the rollers; and the tailstock should be redesigned to eliminate the cylindrical stress concentrator in the center.

  20. The transverse spin

    Energy Technology Data Exchange (ETDEWEB)

    Artru, X. [Institut de Physique Nucleaire de Lyon, IN2P3-CNRS, Universite Claude Bernard, 43 boulevard du 11 Novembre 1918, F-69622 Villeurbanne (France)

    2002-07-01

    The aim of this introduction, which is far from exhaustive, was to give an overview on the richness of transverse spin quantity and its differences in comparison with helicity. From the experimental point of view, the physics of quark transversity in deep inelastic reaction is still practically unexplored. This situation will certainly change rapidly, with planned experiments at DESY (HERMES), Brookhaven (RHIC) and CERN (COMPAS), but there is a long way before knowing the transversity distribution, {delta}q(x), as precisely as the helicity distribution, {delta}q(x), now. Unless polarized anti-proton beams become feasible, experiments probing quark transversity will rely mainly on 'quark polarimeters', like {lambda}'s or the Collins effect. These polarimeters will have to be calibrated at e{sup +}e{sup -} colliders. The Collins polarimeter will by the way allow the flavor decomposition of {delta}q(x), using mesons of various charging and strangeness. Quark polarimetry is by itself an interesting topic of non-perturbative QCD, and may teach us something about the breaking of chiral symmetry. Let us recall that, if chiral symmetry were unbroken, transversity would be undefined. The transversity physics program is not at all a 'remake' of the helicity one. Helicity and transversity probe rather different aspects of the hadron structure. Differences between {delta}q(x) and {delta}q(x) will reveal non-relativistic effects in the baryon wave function. Also {delta}q(x) does not couples to gluon distributions, thus it is free from anomaly. In that respect it is a more clean probe than {delta}q(x). In fact, the combination of helicity and transversity measurements will perhaps be the most interesting. Polarized parton densities taking only the helicity degree of freedom are almost 'classical'. Quantum aspects of spin correlations, like violation of Bell's inequality, can be found only when varying the spin quantification axis

  1. Persistence of contrasting traditions in cultural evolution: unpredictable payoffs generate slower rates of cultural change.

    Directory of Open Access Journals (Sweden)

    Christine A Caldwell

    Full Text Available We report an experimental test of the hypothesis that contrasting traditions will persist for longer, maintaining cultural differences between otherwise similar groups, under conditions of uncertainty about payoffs from individual learning. We studied the persistence of two alternative, experimentally-introduced, task solutions in chains of human participants. In some chains, participants were led to believe that final payoffs would be difficult to predict for an innovative solution, and in others, participants were aware that their final payoff would be directly linked to their immediate solution. Although the difference between the conditions was illusory (only participants' impressions were manipulated, not actual payoffs clear differences were found between the conditions. Consistent with predictions, in the chains that were less certain about final payoffs, the distinctive variants endured over several replacement "generations" of participants. In contrast, in the other chains, the influence of the experimentally-introduced solutions was rapidly diluted by participants' exploration of alternative approaches. The finding provides support for the notion that rates of cultural change are likely to be slower for behaviors for which the relationship between performance and payoff may be hard to predict.

  2. Anti-islanding Protection of Distributed Generation Using Rate of Change of Impedance

    Science.gov (United States)

    Shah, Pragnesh; Bhalja, Bhavesh

    2013-08-01

    Distributed Generation (DG), which is interlinked with distribution system, has inevitable effect on distribution system. Integrating DG with the utility network demands an anti-islanding scheme to protect the system. Failure to trip islanded generators can lead to problems such as threats to personnel safety, out-of-phase reclosing, and degradation of power quality. In this article, a new method for anti-islanding protection based on impedance monitoring of distribution network is carried out in presence of DG. The impedance measured between two phases is used to derive the rate of change of impedance (dz/dt), and its peak values are used for final trip decision. Test data are generated using PSCAD/EMTDC software package and the performance of the proposed method is evaluated in MatLab software. The simulation results show the effectiveness of the proposed scheme as it is capable to detect islanding condition accurately. Subsequently, it is also observed that the proposed scheme does not mal-operate during other disturbances such as short circuit and switching event.

  3. The Impact of DSM-5 A-Criteria Changes on Parent Ratings of ADHD in Adolescents.

    Science.gov (United States)

    Sibley, Margaret H; Yeguez, Carlos E

    2018-01-01

    Diagnostic and Statistical Manual of Mental Disorders (5th ed.; DSM-5) A-criteria for ADHD were expanded to include new descriptors referencing adolescent and adult symptom manifestations. This study examines the effect of these changes on symptom endorsement in a sample of adolescents with ADHD (N = 259; age range = 10.72-16.70). Parent ratings were collected and Diagnostic and Statistical Manual of Mental Disorders (4th ed., text rev.; DSM-IV-TR) and DSM-5 endorsement of ADHD symptoms were compared. Under the DSM-5, there were significant increases in reported inattention, but not hyperactivity/impulsivity (H/I) symptoms, with specific elevations for certain symptoms. The average adolescent met criteria for less than one additional symptom under the DSM-5, but the correlation between ADHD symptoms and impairment was attenuated when using the DSM-5 items. Impulsivity items appeared to represent adolescent deficits better than hyperactivity items. Results were not moderated by demographic factors. In a sample of adolescents with well-diagnosed DSM-IV-TR ADHD, developmental symptom descriptors led parents to endorse slightly more symptoms of inattention, but this elevation is unlikely to be clinically meaningful.

  4. Safewalk: Improving Enrichment and Adoption Rates for Shelter Dogs by Changing Human Behavior.

    Science.gov (United States)

    Bright, Terri M; Hadden, Louise

    2017-01-01

    Shelter dogs are typically cared for by staff and volunteers. At the Boston location of the Massachusetts Society for the Prevention of Cruelty to Animals, prior to 2009, any member of the public who was older than 16 years of age and attended 1 orientation could walk dogs available for adoption. There was no systematic method of training volunteers or staff to walk unruly, strong, or fearful dogs, nor was there any organized system of enrichment in the form of in-kennel or out-of-kennel training for the population of 20 to 40 dogs in the shelter. Using the Dick and Carey ( 1996 ) model of instructional design, a curriculum called "Safewalk" was devised and implemented. Safewalk created a hierarchical training system for volunteers. After training was implemented, outcomes and lengths of stay were then compared for dogs for the 3 years before and 4 years after Safewalk. Changes in adoption rates for pit bull-type dogs and non-pit bulls were significantly improved, and length of stay for non-pit bulls was significantly decreased. Other components of shelter life for dogs and people were also improved.

  5. Metamemory ratings predict long-term changes in reactivated episodic memories

    Directory of Open Access Journals (Sweden)

    Amnon eYacoby

    2015-02-01

    Full Text Available Reactivation of long-term memory can render the memory item temporarily labile, offering an opportunity to modify it via behavioral or pharmacological intervention. Declarative memory reactivation is accompanied by a metamemory ability to subjectively assess the knowledge available concerning the target item (Feeling of knowing, FOK. We set out to examine whether FOK can predict the extent of change of long-term episodic memories by post-retrieval manipulations. To this end, participants watched a short movie and immediately thereafter tested on their memory for it. A day later, they were reminded of that movie, and either immediately or one day later, were presented with a second movie. The reminder phase consisted of memory cues to which participants were asked to judge their FOK regarding the original movie. The memory performance of participants to whom new information was presented immediately after reactivating the original episode corresponded to the degree of FOK ratings upon reactivation such that the lower their FOK, the less their memory declined. In contrast, no relation was found between FOK and memory strength for those who learned new information one day after the reminder phase. Our findings suggest that the subjective accessibility of reactivated memories may determine the extent to which new information might modify those memories.

  6. Honeycomb artificial spin ice at low temperatures

    Science.gov (United States)

    Zeissler, Katharina; Chadha, Megha; Cohen, Lesley; Branford, Will

    2015-03-01

    Artificial spin ice is a macroscopic playground for magnetically frustrated systems. It consists of a geometrically ordered but magnetically frustrated arrangement of ferromagnetic macros spins, e.g. an arrangement of single domain ferromagnetic nanowires on a honeycomb lattice. Permalloy and cobalt which have critical temperature scales far above 290 K, are commonly used in the construction of such systems. Previous measurements have shown unusual features in the magnetotransport signature of cobalt honeycomb artificial spin ice at temperatures below 50 K which are due to changes in the artificial spin ice's magnetic reversal. In that case, the artificial spin ice bars were 1 micron long, 100 nm wide and 20 nm thick. Here we explore the low temperature magnetic behavior of honeycomb artificial spin ice structures with a variety of bar dimensions, indirectly via electrical transport, as well as, directly using low temperature magnetic imaging techniques. We discuss the extent to which this change in the magnetic reversal at low temperatures is generic to the honeycomb artificial spin ice geometry and whether the bar dimensions have an influence on its onset temperature. The EPSRC (Grant No. EP/G004765/1; Grant No. EP/L504786/1) and the Leverhulme Trust (Grant No. RPG 2012-692) funded this scientific work.

  7. Seasonal changes in 24-h patterns of suicide rates : a study on train suicides in The Netherlands

    NARCIS (Netherlands)

    van Houwelingen, CAJ; Beersma, DGM; Houwelingen, Cornelis A.J. van

    2001-01-01

    Background: Annual patterns in suicide rates, peaking near the summer solstice, are well documented. It has been suggested that day length or total hours of sunshine has an impact on suicide rates. If these environmental factors are involved, we would expect changes in the daily pattern of suicide

  8. The impact of gear regulation changes on discard rates: the case of the Baltic Sea cod fishery

    DEFF Research Database (Denmark)

    Feekings, Jordan P.; Madsen, Niels; Lewy, Peter

    2012-01-01

    in minimum landing size (MLS) have had any marked effect on the discard rates of the target species, cod. Results show that the gear regulation changes enforced in the Baltic demersal trawl fishery have had diverse effects on discard rates and are largely dependent on the gear, recruitment, and compliance...

  9. Effect of Dynamic Change in Strain Rate on Mechanical and Stress Corrosion Cracking Behavior of a Mild Steel

    Science.gov (United States)

    Krishnan, Govinda; Varshney, A.; Parameswaran, Venkitanarayanan; Mondal, K.

    2017-05-01

    The current work analyzes the effect of the dynamic change in strain rate during tensile loading of a mild steel on its mechanical and stress corrosion behavior in 3.5 wt.% NaCl solution. The sample experiences high strain rate (10-2 s-1) up to 10, 15 and 20% of total deformation and then very low strain rate of 10-6 s-1 till fracture without any unloading in between. The behavioral characteristics of the steel under these circumstances are found to be different from that exhibited during complete loading till fracture both at high and slow strain rates separately. Total strain increases with the increase in the strain at which change in strain rate happens, and this is attributed to the generation of large number of dislocations at higher strain rate and subsequently release of dislocation at low strain rate during change over due to more time available for dynamic recovery. This observation is common for both in air and corrosive environment. One unique observation in this study is the higher total strain and lower strength observed during dynamic change in strain rate in the corrosive environment compared to that in air, which is attributed to the hydrogen-induced plasticity mechanism.

  10. Influence of transvaginal ultrasound-guided follicular punctures in the mare on heart rate, respiratory rate, facial expression changes, and salivary cortisol as pain scoring.

    Science.gov (United States)

    Diego, Rodrigo; Douet, Cécile; Reigner, Fabrice; Blard, Thierry; Cognié, Juliette; Deleuze, Stefan; Goudet, Ghylène

    2016-10-15

    Transvaginal ultrasound-guided follicular punctures are widely used in the mare for diagnosis, research, and commercial applications. The objective of our study was to determine their influence on pain, stress, and well-being in the mare, by evaluating heart rate, breath rate, facial expression changes, and salivary cortisol before, during, and after puncture. For this experiment, 21 pony mares were used. Transvaginal ultrasound-guided aspirations were performed on 11 mares. After injections for sedation, analgesia, and antispasmodia, the follicles from both ovaries were aspirated with a needle introduced through the vagina wall into the ovary. In the control group, 10 mares underwent similar treatments and injections, but no follicular aspiration. Along the session, heart rate and breath rate were evaluated by a trained veterinarian, ears position, eyelid closure, and contraction of facial muscles were evaluated, and salivary samples were taken for evaluation of cortisol concentration. A significant relaxation was observed after sedative injection in the punctured and control mares, according to ear position, eyelid closure, and contraction of facial muscles, but no difference between punctured and control animals was recorded. No significant modification of salivary cortisol concentration during puncture and no difference between punctured and control mares at any time were observed. No significant modification of the breath rate was observed along the procedure for the punctured and the control mares. Heart rate increased significantly but transiently when the needle was introduced in the ovary and was significantly higher at that time for the punctured mares than that for control mares. None of the other investigated parameters were affected at that time, suggesting discomfort is minimal and transient. Improving analgesia, e.g., through a multimodal approach, during that possibly more sensitive step could be recommended. The evaluation of facial expression

  11. The susceptibilities in the spin-S Ising model

    International Nuclear Information System (INIS)

    Ainane, A.; Saber, M.

    1995-08-01

    The susceptibilities of the spin-S Ising model are evaluated using the effective field theory introduced by Tucker et al. for studying general spin-S Ising model. The susceptibilities are studied for all spin values from S = 1/2 to S = 5/2. (author). 12 refs, 4 figs

  12. Spin-polarized deuterium in magnetic traps

    International Nuclear Information System (INIS)

    Koelman, J.M.V.A.; Stoof, H.T.C.; Verhaar, B.J.; Walraven, J.T.M.

    1987-01-01

    We have calculated the spin-exchange two-body rate constants associated with the population dynamics of the hyperfine levels of atomic deuterium as a function of magnetic field in the Boltzmann zero-temperature limit. Results indicate that a gas of low-field--seeking deuterium atoms trapped in a static magnetic field minimum decays rapidly into an ultrastable gas of doubly spin-polarized deuterium. We also discuss the temperature dependence of various effects

  13. It's All How You "Spin" It: Interpretive Bias in Research Findings in the Obstetrics and Gynecology Literature.

    Science.gov (United States)

    Turrentine, Mark

    2017-02-01

    Scientific publications can be subject to varying degrees of interpretive bias, also known as spin. The rate of spin in randomized controlled trials (RCTs) with nonsignificant primary outcomes in the general obstetrics and gynecology literature is unknown. A decade (January 2006 through December 2015) of the tables of contents of Obstetrics & Gynecology and the American Journal of Obstetrics & Gynecology were screened, with 503 RCTs identified. Limiting assessment to only parallel-group RCTs with a nonsignificant primary outcome (P≥.05) resulted in the identification of 194 studies. The abstracts of the articles reported the primary outcome in 93% of studies with 79% containing a precision estimate but only 25% noting an effect size. The extent of any type of spin occurred in 43% of abstracts and 50% of the main text. In articles that contained spin in the abstract, the more common types were: emphasizing statistically significant secondary results despite a nonsignificant primary outcome (40%); interpreting statistically nonsignificant primary results as showing treatment equivalence or comparable effectiveness (37%); and emphasizing the beneficial effect of the treatment despite statistically nonsignificant results (15%). Half of parallel-group RCTs with nonsignificant primary outcomes published in the two leading journals in general obstetrics and gynecology contains some level of spin. As readers of the medical literature, we should be aware of the concept of spin, the diversity and heterogeneity of spin in the reporting of conclusions, and its effects, particularly when discussing articles that may change clinical practice.

  14. Analyzing General Chemistry Texts' Treatment of Rates of Change Concepts in Reaction Kinetics Reveals Missing Conceptual Links

    Science.gov (United States)

    Seethaler, Sherry; Czworkowski, John; Wynn, Lynda

    2018-01-01

    Change over time is a crosscutting theme in the sciences that is pivotal to reaction kinetics, an anchoring concept in undergraduate chemistry, and students' struggles with rates of change are well-documented. Informed by the education scholarship in chemistry, physics, and mathematics, a research team with members from complementary disciplinary…

  15. Initial turnover rates of two standard wood substrates following land-use change in subalpine ecosystems in the Swiss Alps

    Science.gov (United States)

    Anita C. Risch; Martin F. Jurgensen; Deborah S. Page-Dumroese; Martin Schutz

    2013-01-01

    Forest cover has increased in mountainous areas of Europe over the past decades because of the abandonment of agricultural areas (land-use change). For this reason, understanding how land-use change affects carbon (C) source-sink strength is of great importance. However, most studies have assessed mountainous systems C stocks, and less is known about C turnover rates,...

  16. Quantum statistical metastability for a finite spin

    Science.gov (United States)

    Garanin, D. A.; Chudnovsky, E. M.

    2001-01-01

    We study quantum-classical escape-rate transitions for uniaxial and biaxial models with finite spins S=10 (such as Mn12Ac and Fe8) and S=100 by a direct numerical approach. At second-order transitions the level making a dominant contribution into thermally assisted tunneling changes gradually with temperature whereas at first-order transitions a group of levels is skipped. For finite spins, the quasiclassical boundaries between first- and second-order transitions are shifted, favoring a second-order transition: For Fe8 in zero field the transition should be first order according to a theory with S-->∞, but we show that there are no skipped levels at the transition. Applying a field along the hard axis in Fe8 makes transition the strongest first order. For the same model with S=100 we confirmed the existence of a region where a second-order transition is followed by a first-order transition [X. Martínes Hidalgo and E. M. Chudnovsky, J. Phys.: Condensed Matter 12, 4243 (2000)].

  17. Simultaneous tracking of spin angle and amplitude beyond classical limits

    Science.gov (United States)

    Colangelo, Giorgio; Ciurana, Ferran Martin; Bianchet, Lorena C.; Sewell, Robert J.; Mitchell, Morgan W.

    2017-03-01

    Measurement of spin precession is central to extreme sensing in physics, geophysics, chemistry, nanotechnology and neuroscience, and underlies magnetic resonance spectroscopy. Because there is no spin-angle operator, any measurement of spin precession is necessarily indirect, for example, it may be inferred from spin projectors at different times. Such projectors do not commute, and so quantum measurement back-action—the random change in a quantum state due to measurement—necessarily enters the spin measurement record, introducing errors and limiting sensitivity. Here we show that this disturbance in the spin projector can be reduced below N1/2—the classical limit for N spins—by directing the quantum measurement back-action almost entirely into an unmeasured spin component. This generates a planar squeezed state that, because spins obey non-Heisenberg uncertainty relations, enables simultaneous precise knowledge of spin angle and spin amplitude. We use high-dynamic-range optical quantum non-demolition measurements applied to a precessing magnetic spin ensemble to demonstrate spin tracking with steady-state angular sensitivity 2.9 decibels below the standard quantum limit, simultaneously with amplitude sensitivity 7.0 decibels below the Poissonian variance. The standard quantum limit and Poissonian variance indicate the best possible sensitivity with independent particles. Our method surpasses these limits in non-commuting observables, enabling orders-of-magnitude improvements in sensitivity for state-of-the-art sensing and spectroscopy.

  18. Higher spin gauge theories

    CERN Document Server

    Henneaux, Marc; Vasiliev, Mikhail A

    2017-01-01

    Symmetries play a fundamental role in physics. Non-Abelian gauge symmetries are the symmetries behind theories for massless spin-1 particles, while the reparametrization symmetry is behind Einstein's gravity theory for massless spin-2 particles. In supersymmetric theories these particles can be connected also to massless fermionic particles. Does Nature stop at spin-2 or can there also be massless higher spin theories. In the past strong indications have been given that such theories do not exist. However, in recent times ways to evade those constraints have been found and higher spin gauge theories have been constructed. With the advent of the AdS/CFT duality correspondence even stronger indications have been given that higher spin gauge theories play an important role in fundamental physics. All these issues were discussed at an international workshop in Singapore in November 2015 where the leading scientists in the field participated. This volume presents an up-to-date, detailed overview of the theories i...

  19. Spin caloritronics in graphene

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, Angsula; Frota, H. O. [Department of Physics, Federal University of Amazonas, Av. Rodrigo Octavio 3000-Japiim, 69077-000 Manaus, AM (Brazil)

    2015-06-14

    Spin caloritronics, the combination of spintronics with thermoelectrics, exploiting both the intrinsic spin of the electron and its associated magnetic moment in addition to its fundamental electronic charge and temperature, is an emerging technology mainly in the development of low-power-consumption technology. In this work, we study the thermoelectric properties of a Rashba dot attached to two single layer/bilayer graphene sheets as leads. The temperature difference on the two graphene leads induces a spin current, which depends on the temperature and chemical potential. We demonstrate that the Rashba dot behaves as a spin filter for selected values of the chemical potential and is able to filter electrons by their spin orientation. The spin thermopower has also been studied where the effects of the chemical potential, temperature, and also the Rashba term have been observed.

  20. Spin caloritronics in graphene

    Science.gov (United States)

    Frota, H. O.; Ghosh, Angsula

    2014-08-01

    Spin caloritronics, the combination of spintronics with thermoelectrics, based on spin and heat transport has attracted a great attention mainly in the development of low-power-consumption technology. In this work we study the thermoelectric properties of a quantum dot attached to two single layer graphene sheets as leads. The temperature difference on the two graphene leads induces a spin current which depends on the temperature and chemical potential. We demonstrate that the quantum dot behaves as a spin filter for selected values of the chemical potential and is able to filter electrons by their spin orientation. The spin thermopower has also been studied where the effects of the chemical potential, temperature and also the Coulomb repulsion due to the double occupancy of an energy level have been observed.

  1. STRUCTURAL AND FUNCTIONAL CHANGES EVALUATED BY ECHOCARDIOGRAPHY IN PATIENTS WITH SYSTEMIC SCLEROSIS AND HEART RATE VARIABILITY

    Directory of Open Access Journals (Sweden)

    E. O. Saad

    2017-01-01

    Full Text Available Objective: to estimate heart rate variability (HRV in patients with systemic sclerosis (SS and to investigate their relationship to echocardiographic structural and functional changes in the heart.Subjects and methods. The investigation enrolled 125 patients with SS and 50 gender- and age-matched apparently healthy individuals who made up a control group. In addition to clinical examinations, 73 patients underwent HRV assessment from 24-hour Holter electrocardiogram (ECG monitoring results and 121 patients had echocardiography (EchoCG. 24-hour Holter ECG monitoring was carried out in all control individuals.Results and discussion. Examination of the main parameters of time-domain HRV in patients with SS revealed a significant decline in all temporal and spectral indices, except for the mean R–R interval duration (meanNN, as compared with the control group. EchoCG detected a variety of changes, primarily the induration and calcification of aortic and mitral valves in most patients. Left ventricular diastolic dysfunction was encountered in almost half of the patients with SS. Eight patients had a lower left ventricular ejection fraction (LVEF, which was <55%. Studying the association of HRV values with separate EchoCG parameters revealed significant inverse correlations of the mean standard deviation of R–R intervals in 5-minute recording segments during 24 hours with the thickness of the interventricular septum (r = -0.18; p < 0.05 and with the induration of the aortic valve (r = -0.18; p < 0.05; the square root mean squared of successive differences (RMSSD, ms for R–R intervals and the percentage of adjacent R–R intervals that varied by more than 50 ms (pNN50 correlated with the induration of the aortic valve (r = -0.23; p<0.05 and r = -0.25; p < 0.05, respectively, with the presence of pericarditis (r = -0.24; p < 0.05 and r = -0,27; p < 0.05, respectively, and with the level of pulmonary artery systolic pressure (r = -0

  2. Nanoscale spin sensing in artificial cell membranes

    International Nuclear Information System (INIS)

    Simpson David

    2014-01-01

    The use of the nitrogen-vacancy (NV) centre in diamond as a single spin sensor or magnetometer has attracted considerable interest in recent years because of its unique combination of sensitivity, nanoscale resolution, and optical initialisation and readout at room temperature. Nanodiamonds in particular hold great promise as an optical magnetometer probe for bio applications. In this work we employ nanodiamonds containing single NV spins to detect freely diffusing Mn2+ ions by detecting changes in the transverse relaxation time (T2) of the single spin probe. We also report the detection of gadolinium spin labels present in an artificial cell membrane by measuring changes in the longitudinal relaxation time (T1) of the probe. (author)

  3. Electronic spin transport and spin precession in single graphene layers at room temperature.

    Science.gov (United States)

    Tombros, Nikolaos; Jozsa, Csaba; Popinciuc, Mihaita; Jonkman, Harry T; van Wees, Bart J

    2007-08-02

    Electronic transport in single or a few layers of graphene is the subject of intense interest at present. The specific band structure of graphene, with its unique valley structure and Dirac neutrality point separating hole states from electron states, has led to the observation of new electronic transport phenomena such as anomalously quantized Hall effects, absence of weak localization and the existence of a minimum conductivity. In addition to dissipative transport, supercurrent transport has also been observed. Graphene might also be a promising material for spintronics and related applications, such as the realization of spin qubits, owing to the low intrinsic spin orbit interaction, as well as the low hyperfine interaction of the electron spins with the carbon nuclei. Here we report the observation of spin transport, as well as Larmor spin precession, over micrometre-scale distances in single graphene layers. The 'non-local' spin valve geometry was used in these experiments, employing four-terminal contact geometries with ferromagnetic cobalt electrodes making contact with the graphene sheet through a thin oxide layer. We observe clear bipolar (changing from positive to negative sign) spin signals that reflect the magnetization direction of all four electrodes, indicating that spin coherence extends underneath all of the contacts. No significant changes in the spin signals occur between 4.2 K, 77 K and room temperature. We extract a spin relaxation length between 1.5 and 2 mum at room temperature, only weakly dependent on charge density. The spin polarization of the ferromagnetic contacts is calculated from the measurements to be around ten per cent.

  4. The basics of neutron spin echo

    International Nuclear Information System (INIS)

    Farago, B.

    1999-01-01

    Until 1974 inelastic neutron scattering consisted of producing by some means a neutron beam of known speed and measuring the final speed of the neutrons after the scattering event. The smaller the energy change was, the better the neutron speed had to be defined. As the neutrons come form a reactor with an approximately Maxwell distribution, an infinitely good energy resolution can be achieved only at the expense of infinitely low count rate. This introduces a practical resolution limit around 0.1 μeV on back-scattering instruments. In 1972 F. Mezei discovered the method of Neutron Spin Echo. This method decouples the energy resolution from intensity loss. The basics of this method is presented. (author)

  5. The heritability of level and rate-of-change in cognitive functioning in Danish twins aged 70 years and older

    DEFF Research Database (Denmark)

    McGue, Matt; Christensen, Kaare

    2002-01-01

    was highly heritable (h(2) = .76, 95% confidence interval of .68 to .82), the rate of linear change was not (h(2) = .06, 95% confidence interval of .00 to .57). These findings suggest that the search for specific genes might reasonably focus on average level of cognitive performance, whereas specific......To investigate heritable influences on overall level and rate-of-change in cognitive ability, biometric growth models were fit to cognitive data from nearly 1000 Danish twins age 70 years and older. Twins are participants in the ongoing Longitudinal Study of Aging Danish Twins, a cohort...... environmental influences might account for cognitive change....

  6. Spin and Maximal Acceleration

    Directory of Open Access Journals (Sweden)

    Giorgio Papini

    2017-12-01

    Full Text Available We study the spin current tensor of a Dirac particle at accelerations close to the upper limit introduced by Caianiello. Continual interchange between particle spin and angular momentum is possible only when the acceleration is time-dependent. This represents a stringent limit on the effect that maximal acceleration may have on spin physics in astrophysical applications. We also investigate some dynamical consequences of maximal acceleration.

  7. Spin Hall effect devices

    Czech Academy of Sciences Publication Activity Database

    Jungwirth, Tomáš; Wunderlich, Joerg; Olejník, Kamil

    2012-01-01

    Roč. 11, č. 5 (2012), s. 382-390 ISSN 1476-1122 EU Projects: European Commission(XE) 268066 - 0MSPIN; European Commission(XE) 215368 - SemiSpinNet Grant - others:AV ČR(CZ) AP0801 Program:Akademická prémie - Praemium Academiae Institutional research plan: CEZ:AV0Z10100521 Keywords : spin Hall effect * spintronics * spin transistor Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 35.749, year: 2012

  8. Livaditis' circular myotomy does not decrease anastomotic leak rates and induces deleterious changes in anastomotic healing.

    Science.gov (United States)

    Tannuri, U; Teodoro, W R; de Santana Witzel, S; Tannuri, A C A; Lupinacci, R M; Matsunaga, P; Matsumura, N; Naufal, R R

    2003-08-01

    Considering that Livaditis' myotomy is still accepted as a good method for lengthening the esophagus to allow primary repair of long-gap esophageal atresia, the aim of this experimental study was to verify if this procedure decreases the incidence of leaks in anastomoses performed under severe tension. In addition, it was verified whether the myotomy promotes any morphological or biochemical change in the healing esophageal anastomosis. Sixty small dogs were submitted to a cervicotomy and resection of an esophageal segment (8.0 - 10.0 cm) resulting in an anastomosis under severe tension. The animals were divided into two groups (control group: only anastomosis; experimental group: anastomosis plus circular myotomy in the proximal esophageal segment). The animals were sacrificed on the 14th postoperative day, submitted to autopsy, and were evaluated as to the presence of leaks. Twelve scars of each group were collected for histological, histomorphometric (evaluation of scar thickness), electrophoretic and immunoblotting studies of collagen (total collagen and types of collagen determinations). Leak rates were the same in both groups. Histologic examination showed that the scar at the anastomosis was formed by fibrous tissue, without mucosa or muscular tissue. In the myotomy animals, a decreased number of newly formed small vessels was noted in comparison to control animals, and morphometric analysis showed that in the myotomy animals the anastomotic scar was thinner than in the control animals. Biochemical analysis of scars demonstrated that myotomy promoted a decrease in the soluble collagen content in comparison with the control animals and no alteration in the content of insoluble collagen. The electrophoretic separation of the types of collagen and characterization by immunoblotting demonstrated the presence of collagen types I, III, and V, and the quantification by densitometry of the bands showed a reduction in collagen type V (present in the blood vessels) in

  9. Time-dependent 31P saturation transfer in the phosphoglucomutase reaction. Characterization of the spin system for the Cd(II) enzyme and evaluation of rate constants for the transfer process

    International Nuclear Information System (INIS)

    Post, C.B.; Ray, W.J. Jr.; Gorenstein, D.G.

    1989-01-01

    Time-dependent 31 P saturation-transfer studies were conducted with the Cd 2+ -activated form of muscle phosphoglucomutase to probe the origin of the 100-fold difference between its catalytic efficiency (in terms of k cat ) and that of the more efficient Mg 2+ -activated enzyme. The present paper describes the equilibrium mixture of phosphoglucomutase and its substrate/product pair when the concentration of the Cd 2+ enzyme approaches that of the substrate and how the nine-spin 31 P NMR system provided by this mixture was treated. It shows that the presence of abortive complexes is not a significant factor in the reduced activity of the Cd 2+ enzyme since the complex of the dephosphoenzyme and glucose 1,6-bisphosphate, which accounts for a large majority of the enzyme present at equilibrium, is catalytically competent. It also shows that rate constants for saturation transfer obtained at three different ratios of enzyme to free substrate are mutually compatible. These constants, which were measured at chemical equilibrium, can be used to provide a quantitative kinetic rationale for the reduced steady-state activity elicited by Cd 2+ relative to Mg 2+ . They also provide minimal estimates of 350 and 150 s -1 for the rate constants describing (PO 3 - ) transfer from the Cd 2+ phosphoenzyme to the 6-position of bound glucose 1-phosphate and to the 1-position of bound glucose 6-phosphate, respectively. These minimal estimates are compared with analogous estimates for the Mg 2+ and Li + forms of the enzyme in the accompanying paper

  10. High spin spectroscopy of Pr

    Indian Academy of Sciences (India)

    2001-07-31

    Jul 31, 2001 ... High spin states; nuclear structure; gamma-ray spectroscopy;. ½¿. Pr energy levels. PACS Nos 21.10.-k; 23.20.-g; 27.60.+j; 29.30.Kv. 1. Introduction. The transitional nuclei in the A. ½ ¼ region with N between 77 and 81 are interesting as it offer good scope to look for possible shape changes, similar to ...

  11. Pure spin current manipulation in antiferromagnetically exchange coupled heterostructures

    Science.gov (United States)

    Avilés-Félix, L.; Butera, A.; González-Chávez, D. E.; Sommer, R. L.; Gómez, J. E.

    2018-03-01

    We present a model to describe the spin currents generated by ferromagnet/spacer/ferromagnet exchange coupled trilayer systems and heavy metal layers with strong spin-orbit coupling. By exploiting the magnitude of the exchange coupling (oscillatory RKKY-like coupling) and the spin-flop transition in the magnetization process, it has been possible to produce spin currents polarized in arbitrary directions. The spin-flop transition of the trilayer system originates pure spin currents whose polarization vector depends on the exchange field and the magnetization equilibrium angles. We also discuss a protocol to control the polarization sign of the pure spin current injected into the metallic layer by changing the initial conditions of magnetization of the ferromagnetic layers previously to the spin pumping and inverse spin Hall effect experiments. The small differences in the ferromagnetic layers lead to a change in the magnetization vector rotation that permits the control of the sign of the induced voltage components due to the inverse spin Hall effect. Our results can lead to important advances in hybrid spintronic devices with new functionalities, particularly, the ability to control microscopic parameters such as the polarization direction and the sign of the pure spin current through the variation of macroscopic parameters, such as the external magnetic field or the thickness of the spacer in antiferromagnetic exchange coupled systems.

  12. Quantum spin Hall phases

    International Nuclear Information System (INIS)

    Murakami, Shuichi

    2009-01-01

    We review our recent theoretical works on the quantum spin Hall effect. First we compare edge states in various 2D systems, and see whether they are robust or fragile against perturbations. Through the comparisons we see the robust nature of edge states in 2D quantum spin Hall phases. We see how it is protected by the Z 2 topological number, and reveal the nature of the Z 2 topological number by studying the phase transition between the quantum spin Hall and insulator phases. We also review our theoretical proposal of the ultrathin bismuth film as a candidate to the 2D quantum spin Hall system. (author)

  13. Local Noncollinear Spin Analysis.

    Science.gov (United States)

    Abate, Bayileyegn A; Joshi, Rajendra P; Peralta, Juan E

    2017-12-12

    In this work, we generalize the local spin analysis of Clark and Davidson [J. Chem. Phys. 2001 115 (16), 7382] for the partitioning of the expectation value of the molecular spin square operator, ⟨Ŝ 2 ⟩, into atomic contributions, ⟨Ŝ A ·Ŝ B ⟩, to the noncollinear spin case in the framework of density functional theory (DFT). We derive the working equations, and we show applications to the analysis of the noncollinear spin solutions of typical spin-frustrated systems and to the calculation of magnetic exchange couplings. In the former case, we employ the triangular H 3 He 3 test molecule and a Mn 3 complex to show that the local spin analysis provides additional information that complements the standard one-particle spin population analysis. For the calculation of magnetic exchange couplings, J AB , we employ the local spin partitioning to extract ⟨Ŝ A ·Ŝ B ⟩ as a function of the interatomic spin orientation given by the angle θ. This, combined with the dependence of the electronic energy with θ, provides a methodology to extract J AB from DFT calculations that, in contrast to conventional energy differences based methods, does not require the use of ad hoc S A and S B values.

  14. Spin glasses (II)

    International Nuclear Information System (INIS)

    Fischer, K.H.

    1985-01-01

    Experimental results of spin glass studies are reviewed and related to existing theories. Investigations of spin glasses are concentrated on atomic structure, metallurgical treatment, and high-temperature susceptibility of alloys, on magnetic properties at low temperature and near the freezing temperature, on anisotropy behaviour measured by ESR, NMR and torque, on specific heat, Moessbauer effect, neutron scattering and muon-spin depolarization experiments, ultrasound and transport properties. Some new theories of spin glasses are discussed which have been developed since Part I appeared

  15. Estimation of methane emission rate changes using age-defined waste in a landfill site.

    Science.gov (United States)

    Ishii, Kazuei; Furuichi, Toru

    2013-09-01

    Long term methane emissions from landfill sites are often predicted by first-order decay (FOD) models, in which the default coefficients of the methane generation potential and the methane generation rate given by the Intergovernmental Panel on Climate Change (IPCC) are usually used. However, previous studies have demonstrated the large uncertainty in these coefficients because they are derived from a calibration procedure under ideal steady-state conditions, not actual landfill site conditions. In this study, the coefficients in the FOD model were estimated by a new approach to predict more precise long term methane generation by considering region-specific conditions. In the new approach, age-defined waste samples, which had been under the actual landfill site conditions, were collected in Hokkaido, Japan (in cold region), and the time series data on the age-defined waste sample's methane generation potential was used to estimate the coefficients in the FOD model. The degradation coefficients were 0.0501/y and 0.0621/y for paper and food waste, and the methane generation potentials were 214.4 mL/g-wet waste and 126.7 mL/g-wet waste for paper and food waste, respectively. These coefficients were compared with the default coefficients given by the IPCC. Although the degradation coefficient for food waste was smaller than the default value, the other coefficients were within the range of the default coefficients. With these new coefficients to calculate methane generation, the long term methane emissions from the landfill site was estimated at 1.35×10(4)m(3)-CH(4), which corresponds to approximately 2.53% of the total carbon dioxide emissions in the city (5.34×10(5)t-CO(2)/y). Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Orthostatic heart rate changes in patients with autonomic failure caused by neurodegenerative synucleinopathies.

    Science.gov (United States)

    Norcliffe-Kaufmann, Lucy; Kaufmann, Horacio; Palma, Jose-Alberto; Shibao, Cyndya A; Biaggioni, Italo; Peltier, Amanda C; Singer, Wolfgang; Low, Phillip A; Goldstein, David S; Gibbons, Christopher H; Freeman, Roy; Robertson, David

    2018-03-01

    Blunted tachycardia during hypotension is a characteristic feature of patients with autonomic failure, but the range has not been defined. This study reports the range of orthostatic heart rate (HR) changes in patients with autonomic failure caused by neurodegenerative synucleinopathies. Patients evaluated at sites of the U.S. Autonomic Consortium (NCT01799915) underwent standardized autonomic function tests and full neurological evaluation. We identified 402 patients with orthostatic hypotension (OH) who had normal sinus rhythm. Of these, 378 had impaired sympathetic activation (ie, neurogenic OH) and based on their neurological examination were diagnosed with Parkinson disease, dementia with Lewy bodies, pure autonomic failure, or multiple system atrophy. The remaining 24 patients had preserved sympathetic activation and their OH was classified as nonneurogenic, due to volume depletion, anemia, or polypharmacy. Patients with neurogenic OH had twice the fall in systolic blood pressure (SBP; -44 ± 25 vs -21 ± 14 mmHg [mean ± standard deviation], p < 0.0001) but only one-third of the increase in HR of those with nonneurogenic OH (8 ± 8 vs 25 ± 11 beats per minute [bpm], p < 0.0001). A ΔHR/ΔSBP ratio of 0.492 bpm/mmHg had excellent sensitivity (91.3%) and specificity (88.4%) to distinguish between patients with neurogenic from nonneurogenic OH (area under the curve = 0.96, p < 0.0001). Within patients with neurogenic OH, HR increased more in those with multiple system atrophy (p = 0.0003), but there was considerable overlap with patients with Lewy body disorders. A blunted HR increase during hypotension suggests a neurogenic cause. A ΔHR/ΔSBP ratio < 0.5 bpm/mmHg is diagnostic of neurogenic OH. Ann Neurol 2018;83:522-531. © 2018 American Neurological Association.

  17. Time course of changes in heart rate and blood pressure variability in rats with myocardial infarction

    Directory of Open Access Journals (Sweden)

    R. Aires

    Full Text Available Our aim was to determine the time course of changes in autonomic balance in the acute (1 and 3 days, sub-acute (7 days and chronic (28 days phases of myocardial infarction (MI in rats. Autonomic balance was assessed by temporal and spectral analyses of blood pressure variability (BPV and heart rate variability (HRV. Pulsatile blood pressure (BP recordings (30 min were obtained in awake and unrestrained male Wistar rats (N = 77; 8-10 weeks old with MI (coronary ligature or sham operation (SO. Data are reported as means±SE. The high frequency (HF component (n.u. of HRV was significantly lower in MI-1- (P0.05. This reduction was mainly due to attenuation of the low frequency (LF band of BPV in absolute and normalized units (SO-1=39.3±7%; SO-3=55±4.5%; SO-7=46.8±4.5%; SO-28=45.7±5%; MI-1=13±3.5%; MI-3=35±4.7%; MI-7=25±2.8%; MI-28=21.4±2.8%. The results suggest that the reduction in HRV was associated with decrease of the HF component of HRV suggesting recovery of the vagal control of heartbeats along the post-infarction healing period. The depression of BPV was more dependent on the attenuation of the LF component, which is linked to the baroreflex modulation of the autonomic balance.

  18. Temporal changes in suicide rates for persons treated and not treated with antidepressants in Denmark during 1995-1999

    DEFF Research Database (Denmark)

    Søndergård, L; Kvist, K; Lopez, A G

    2006-01-01

    OBJECTIVE: To compare the temporal changes in suicide rate among patients treated with antidepressants with the change in suicide rate among persons who have not been treated with antidepressants during 1995-1999. METHOD: In a historic prospective national pharmacoepidemiological register linkage...... study by using four Danish registers we included 438,625 patients who had purchased antidepressants, and compared them with 1,199,057 population based control persons. The annual rate of suicide was estimated using Poisson regression analyses. RESULTS: The suicide rate decreased for persons treated...... with antidepressants as well as for persons not treated with antidepressants. The proportion of persons, who committed suicide and who had not been treated with antidepressants decreased. The reduction in suicide rate was more pronounced among persons treated with SSRIs or older antidepressants than among persons...

  19. Prediction of hypotension during spinal anesthesia for elective cesarean section by altered heart rate variability induced by postural change.

    Science.gov (United States)

    Sakata, K; Yoshimura, N; Tanabe, K; Kito, K; Nagase, K; Iida, H

    2017-02-01

    Maternal hypotension is a common complication during cesarean section performed under spinal anesthesia. Changes in maternal heart rate with postural changes or values of heart rate variability have been reported to predict hypotension. Therefore, we hypothesized that changes in heart rate variability due to postural changes can predict hypotension. A total of 45 women scheduled to undergo cesarean section under spinal anesthesia were enrolled. A postural change test was performed the day before cesarean section. The ratio of the power of low and high frequency components contributing to heart rate variability was assessed in the order of supine, left lateral, and supine. Patients who exhibited a ⩾two-fold increase in the low-to-high frequency ratio when moving to supine from the lateral position were assigned to the postural change test-positive group. According to the findings of the postural change test, patients were assigned to the positive (n=22) and negative (n=23) groups, respectively. Hypotension occurred in 35/45 patients, of whom 21 (60%) were in the positive group and 14 (40%) were in the negative group. The incidence of hypotension was greater in the positive group (Pcesarean section. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Change in Population Characteristics and Teen Birth Rates in 77 Community Areas: Chicago, Illinois, 1999-2009.

    Science.gov (United States)

    Gunaratne, Shauna; Masinter, Lisa; Kolak, Marynia; Feinglass, Joe

    2015-01-01

    We analyzed community area differences in teen births in Chicago, Illinois, from 1999 to 2009. We analyzed the association between changes in teen birth rates and concurrent measures of community area socioeconomic and demographic change. Mean annual changes in teen birth rates in 77 Chicago community areas were correlated with concurrent census-based population changes during the decade. Census measures included changes in race/ethnicity, adult high school dropouts, poverty or higher-income households, crowded housing, unemployment, English proficiency, foreign-born residents, or residents who moved in the last five years. We included non-collinear census measures with a pteen births in a stepwise multiple linear regression model. Teen birth rates in Chicago fell faster than the overall birth rates, from 85 births per 1,000 teens in 1999 to 57 births per 1,000 teens in 2009. There were strong positive associations between increases in the percentage of residents who were black and Hispanic, poor, without a high school diploma, and living in crowded housing, and a negative association with an increase in higher-income households. Population changes in poverty, Hispanic population, and high school dropouts were the only significant measures in the final model, explaining almost half of the variance in teen birth rate changes. The study provides a model of census-based measures that can be used to evaluate predicted vs. observed rates of change in teen births across communities, offering the potential to more appropriately prioritize public health resources for preventing unintended teen pregnancy.

  1. Cometary spin-down

    Science.gov (United States)

    Agarwal, Jessica

    2018-01-01

    The rotation rate of a comet more than halved in two months -- a much greater change than has previously been observed. This suggests that the comet is in a distinct evolutionary state and might soon reorient itself.

  2. Spin rate distribution of small asteroids

    Czech Academy of Sciences Publication Activity Database

    Pravec, Petr; Harris, A. W.; Vokrouhlický, D.; Warner, B. D.; Kušnirák, Peter; Hornoch, Kamil; Pray, D. P.; Higgins, D.; Oey, J.; Galád, Adrián; Gajdoš, Š.; Kornoš, L.; Világi, J.; Husárik, M.; Krugly, Yu. N.; Shevchenko, V. G.; Chiorny, V. G.; Gaftonyuk, N. M.; Cooney jr., W. R.; Gross, J.; Terrell, D.; Stephens, R.; Dyvig, R.; Reddy, V.; Ries, J.G.; Colas, F.; Lecacheux, J.; Durkee, R.; Masi, G.; Koff, R.; Goncalves, R.

    2008-01-01

    Roč. 197, č. 2 (2008), s. 497-504 ISSN 0019-1035 R&D Projects: GA ČR(CZ) GA205/05/0604 Grant - others:NASA(US) NAG5-13244; NASA(US) NNG06GI32G; VEGA(SK) 1/3074/06; VEGA(SK) 1/3067/06; VEGA(SK) 2/7009/27 Institutional research plan: CEZ:AV0Z10030501 Keywords : asteroids rotation * photometry * near-Earth objects Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 3.268, year: 2008

  3. Understanding changes over time in workers' compensation claim rates using time series analytical techniques.

    Science.gov (United States)

    Moore, Ian C; Tompa, Emile

    2011-11-01

    The objective of this study is to better understand the inter-temporal variation in workers' compensation claim rates using time series analytical techniques not commonly used in the occupational health and safety literature. We focus specifically on the role of unemployment rates in explaining claim rate variations. The major components of workers' compensation claim rates are decomposed using data from a Canadian workers' compensation authority for the period 1991-2007. Several techniques are used to undertake the decomposition and assess key factors driving rates: (i) the multitaper spectral estimator, (ii) the harmonic F test, (iii) the Kalman smoother and (iv) ordinary least squares. The largest component of the periodic behaviour in workers' compensation claim rates is seasonal variation. Business cycle fluctuations in workers' compensation claim rates move inversely to unemployment rates. The analysis suggests that workers' compensation claim rates between 1991 and 2008 were driven by (in order of magnitude) a strong negative long term growth trend, periodic seasonal trends and business cycle fluctuations proxied by the Ontario unemployment rate.

  4. Changes in Children's Peer Interactions Following a Natural Disaster: How Predisaster Bullying and Victimization Rates Changed Following Hurricane Katrina

    Science.gov (United States)

    Terranova, Andrew M.; Boxer, Paul; Morris, Amanda Sheffield

    2009-01-01

    Youth exposed to disasters experience stress and adjustment difficulties, which likely influence their interactions with peers. In this study, we examined changes in bullying and peer victimization in two cohorts of children. Youth from an area affected by Hurricane Katrina were assessed pre- and postdisaster (n = 96, mean [M] = 10.9 years old,…

  5. Noise in tunneling spin current across coupled quantum spin chains

    OpenAIRE

    Aftergood, Joshua; Takei, So

    2017-01-01

    We theoretically study the spin current and its dc noise generated between two spin-1/2 spin chains weakly coupled at a single site in the presence of an over-population of spin excitations and a temperature elevation in one subsystem relative to the other, and compare the corresponding transport quantities across two weakly coupled magnetic insulators hosting magnons. In the spin chain scenario, we find that applying a temperature bias exclusively leads to a vanishing spin current and a conc...

  6. The World is Spinning: Constraining the Origin of Supermassive Gas Giant Planets at Wide Separations Using Planetary Spin

    Science.gov (United States)

    Bryan, Marta; Knutson, Heather; Batygin, Konstantin; Benneke, Björn; Bowler, Brendan

    2017-01-01

    Planetary spin can inform our understanding of planet accretion histories, which determine final masses and atmospheric compositions, as well as the formation of moons and rings. At present, the physics behind how gas giant planets spin up is still very poorly understood. We know that when giant planets form, they accrete material and angular momentum via a circumplanetary disk, causing the planet to spin up. In order to prevent planet spins from reaching break-up velocity, some mechanism must regulate these spins. However, there is currently no well-formulated picture for how planet spins evolve. This is in part due to the fact that there are very few measurements of giant planet spin rates currently available. Outside the solar system, to date there has only been one published spin measurement of a directly imaged planet, beta Pic b. We use Keck/NIRSPEC to measure spin rates for a sample of bound and free-floating directly imaged planetary mass objects, providing a first look at the distribution of spin rates for these objects.

  7. Heart Rate and Oxygen Saturation Change Patterns During 6-min Walk Test in Subjects With Chronic Thromboembolic Pulmonary Hypertension.

    Science.gov (United States)

    Inagaki, Takeshi; Terada, Jiro; Yahaba, Misuzu; Kawata, Naoko; Jujo, Takayuki; Nagashima, Kengo; Sakao, Seiichiro; Tanabe, Nobuhiro; Tatsumi, Koichiro

    2017-12-26

    The 6-min walk test (6MWT) is commonly performed to assess functional status in patients with chronic thromboembolic pulmonary hypertension. However, changes in heart rate and oxygen saturation ( S pO 2 ) patterns during 6MWT in patients with chronic thromboembolic pulmonary hypertension remain unclear. Thirty-one subjects with chronic thromboembolic pulmonary hypertension were retrospectively evaluated to examine the relationships between the change in heart rate (Δheart rate), heart rate acceleration time, slope of heart rate acceleration, heart rate recovery during the first minute after 6MWT (HRR1), change in S pO 2 (Δ S pO 2 ), S pO 2 reduction time, and S pO 2 recovery time during 6MWT, and the severity of pulmonary hemodynamics assessed by right heart catheterization and echocardiography. Subjects with severe chronic thromboembolic pulmonary hypertension had significantly longer heart rate acceleration time (144.9 ± 63.9 s vs 96.0 ± 42.5 s, P = .033), lower Δheart rate (47.4 ± 16.9 vs 61.8 ± 13.6 beats, P = .02), and lower HRR1 (13.3 ± 9.0 beats vs 27.1 ± 9.2 beats, P pulmonary hypertension. Subjects with severe chronic thromboembolic pulmonary hypertension also had significantly longer S pO 2 reduction time (178.3 ± 70.3 s vs 134.3 ± 58.4 s, P = .03) and S pO 2 recovery time (107.6 ± 35.3 s vs 69.8 ± 32.7 s, P = .004) than did subjects with mild chronic thromboembolic pulmonary hypertension. Multivariate linear regression analysis showed only mean pulmonary arterial pressure independently was associated with heart rate acceleration time and slope of heart rate acceleration. Heart rate and S pO 2 change patterns during 6MWT is predominantly associated with pulmonary hemodynamics in subjects with chronic thromboembolic pulmonary hypertension. Evaluating heart rate and S pO 2 change patterns during 6MWT may serve a safe and convenient way to follow the change in pulmonary hemodynamics. Copyright © 2017 by Daedalus Enterprises.

  8. Center of Mass Estimation for a Spinning Spacecraft Using Doppler Shift of the GPS Carrier Frequency

    Science.gov (United States)

    Sedlak, Joseph E.

    2016-01-01

    A sequential filter is presented for estimating the center of mass (CM) of a spinning spacecraft using Doppler shift data from a set of onboard Global Positioning System (GPS) receivers. The advantage of the proposed method is that it is passive and can be run continuously in the background without using commanded thruster firings to excite spacecraft dynamical motion for observability. The NASA Magnetospheric Multiscale (MMS) mission is used as a test case for the CM estimator. The four MMS spacecraft carry star cameras for accurate attitude and spin rate estimation. The angle between the spacecraft nominal spin axis (for MMS this is the geometric body Z-axis) and the major principal axis of inertia is called the coning angle. The transverse components of the estimated rate provide a direct measure of the coning angle. The coning angle has been seen to shift slightly after every orbit and attitude maneuver. This change is attributed to a small asymmetry in the fuel distribution that changes with each burn. This paper shows a correlation between the apparent mass asymmetry deduced from the variations in the coning angle and the CM estimates made using the GPS Doppler data. The consistency between the changes in the coning angle and the CM provides validation of the proposed GPS Doppler method for estimation of the CM on spinning spacecraft.

  9. Controlled spin switching in a metallocene molecular junction.

    Science.gov (United States)

    Ormaza, M; Abufager, P; Verlhac, B; Bachellier, N; Bocquet, M-L; Lorente, N; Limot, L

    2017-12-07

    The active control of a molecular spin represents one of the main challenges in molecular spintronics. Up to now spin manipulation has been achieved through the modification of the molecular structure either by chemical doping or by external stimuli. However, the spin of a molecule adsorbed on a surface depends primarily on the interaction between its localized orbitals and the electronic states of the substrate. Here we change the effective spin of a single molecule by modifying the molecule/metal interface in a controlled way using a low-temperature scanning tunneling microscope. A nickelocene molecule reversibly switches from a spin 1 to 1/2 when varying the electrode-electrode distance from tunnel to contact regime. This switching is experimentally evidenced by inelastic and elastic spin-flip mechanisms observed in reproducible conductance measurements and understood using first principle calculations. Our work demonstrates the active control over the spin state of single molecule devices through interface manipulation.

  10. Modeling rates of life form cover change in burned and unburned alpine heathland subject to experimental warming.

    Science.gov (United States)

    Camac, James S; Williams, Richard J; Wahren, Carl-Henrik; Jarrad, Frith; Hoffmann, Ary A; Vesk, Peter A

    2015-06-01

    Elevated global temperatures are expected to alter vegetation dynamics by interacting with physiological processes, biotic relationships and disturbance regimes. However, few studies have explicitly modeled the effects of these interactions on rates of vegetation change, despite such information being critical to forecasting temporal patterns in vegetation dynamics. In this study, we build and parameterize rate-change models for three dominant alpine life forms using data from a 7-year warming experiment. These models allowed us to examine how the interactions between experimental warming, the abundance of bare ground (a measure of past disturbance) and neighboring life forms (a measure of life form interaction) affect rates of cover change in alpine shrubs, graminoids and forbs. We show that experimental warming altered rates of life form cover change by reducing the negative effects of neighboring life forms and positive effects of bare ground. Furthermore, we show that our models can predict the observed direction and rate of life form cover change at burned and unburned long-term monitoring sites. Model simulations revealed that warming in unburned vegetation is expected to result in increased forb and shrub cover and decreased graminoid cover. In contrast, in burned vegetation, warming is predicted to slow post-fire regeneration in both graminoids and forbs and facilitate rapid expansion in shrub cover. These findings illustrate the applicability of modeling rates of vegetation change using experimental data. Our results also highlight the need to account for both disturbance and the abundance of other life forms when examining and forecasting vegetation dynamics under climatic change.

  11. Investigation of effect of blood pressure and heart rate changes in different positions (lying and sitting on hypotension incidence rate after spinal anesthesia in patients undergoing caesarean section

    Directory of Open Access Journals (Sweden)

    Nahid Manouchehrian

    2016-07-01

    Full Text Available Due to the relatively high prevalence of hypotension (20% -40% after spinal anesthesia as well as the adverse effects of hypotension on mother and baby, it is better to prevent hypotension as much as possible. Therefore, this study is aimed to determine the relationship between postural blood pressure and heart rate changes and hypotension incidence rate after spinal anesthesia in cesarean section.63 women aging18 to 45years old with fullterm pregnancy, who were candidate for caesarean section with spinal anesthesia, entered the study. Afterwards, the diastolic, systolic, and mean arterial pressures as well as the heart rate (pulse in different positions (sitting, lying, and left lateral were measured. After spinal anesthesia, the patients' blood pressure was measured and recorded every minute until the10thmin, then every 3 minute until the15thmin, and then every 5 minute until the end of cesarean section. Data analysis was performed using SPSS (ver. 19 software, descriptive statistics, one-way ANOVA, and post hoc Bonferroni test. In this study, the hypotension incidence rate was 30% and the orthostatic variation rate of the systolic blood pressure in more than half of the people was between 4.39 to 13.49psi, which showed the highest variation compared to the diastolic pressure, mean arterial blood pressure (or: mean arterial pressure [MAP], and heart(pulse. Considering the correlation coefficient of 0.27, the systolic blood pressure in the lateral position has the highest relationship with the incidence of hypotension. The postural systolic blood pressure changes in patients prior to the spinal anesthesia can be a predictive factor for the post-spinal hypotension incidence.

  12. Monetary and exchange rate regimes changes: The cases of Poland, Czech Republic, Slovakia and Republic of Serbia

    Directory of Open Access Journals (Sweden)

    Josifidis Kosta

    2009-01-01

    Full Text Available The paper explores (former transition economies, Poland, Czech Republic, Slovakia and the Republic of Serbia, concerning abandonment of the exchange rate targeting and fixed exchange rate regimes and movement toward explicit/implicit inflation targeting and flexible exchange rate regimes. The paper identifies different subperiods concerning crucial monetary and exchange rate regimes, and tracks the changes of specific monetary transmission channels i.e. exchange rate channel, interest rate channel, indirect and direct influences to the exchange rate, with variance decomposition of VAR/VEC model. The empirical results indicate that Polish monetary strategy toward higher monetary and exchange rate flexibility has been performed smoothly, gradually and planned, compared to the Slovak and, especially, Czech case. The comparison of three former transition economies with the Serbian case indicate strong and persistent exchange rate pass-through, low interest rate pass-through, significant indirect and direct influence to the exchange rate as potential obstacles for successful inflation targeting in the Republic of Serbia.

  13. Effect of spin rotation coupling on spin transport

    International Nuclear Information System (INIS)

    Chowdhury, Debashree; Basu, B.

    2013-01-01

    We have studied the spin rotation coupling (SRC) as an ingredient to explain different spin-related issues. This special kind of coupling can play the role of a Dresselhaus like coupling in certain conditions. Consequently, one can control the spin splitting, induced by the Dresselhaus like term, which is unusual in a semiconductor heterostructure. Within this framework, we also study the renormalization of the spin-dependent electric field and spin current due to the k → ⋅p → perturbation, by taking into account the interband mixing in the rotating system. In this paper we predict the enhancement of the spin-dependent electric field resulting from the renormalized spin rotation coupling. The renormalization factor of the spin electric field is different from that of the SRC or Zeeman coupling. The effect of renormalized SRC on spin current and Berry curvature is also studied. Interestingly, in the presence of this SRC-induced SOC it is possible to describe spin splitting as well as spin galvanic effect in semiconductors. -- Highlights: •Studied effect of spin rotation coupling on the spin electric field, spin current and Berry curvature. •In the k → ⋅p → framework we study the renormalization of spin electric field and spin current. •For an inertial system we have discussed the spin splitting. •Expression for the Berry phase in the inertial system is discussed. •The inertial spin galvanic effect is studied

  14. High-Spin Cobalt Hydrides for Catalysis

    Energy Technology Data Exchange (ETDEWEB)

    Holland, Patrick L. [Univ. of Rochester, NY (United States)

    2013-08-29

    Organometallic chemists have traditionally used catalysts with strong-field ligands that give low-spin complexes. However, complexes with a weak ligand field have weaker bonds and lower barriers to geometric changes, suggesting that they may lead to more rapid catalytic reactions. Developing our understanding of high-spin complexes requires the use of a broader range of spectroscopic techniques, but has the promise of changing the mechanism and/or selectivity of known catalytic reactions. These changes may enable the more efficient utilization of chemical resources. A special advantage of cobalt and iron catalysts is that the metals are more abundant and cheaper than those currently used for major industrial processes that convert unsaturated organic molecules and biofeedstocks into useful chemicals. This project specifically evaluated the potential of high-spin cobalt complexes for small-molecule reactions for bond rearrangement and cleavage reactions relevant to hydrocarbon transformations. We have learned that many of these reactions proceed through crossing to different spin states: for example, high-spin complexes can flip one electron spin to access a lower-energy reaction pathway for beta-hydride elimination. This reaction enables new, selective olefin isomerization catalysis. The high-spin cobalt complexes also cleave the C-O bond of CO2 and the C-F bonds of fluoroarenes. In each case, the detailed mechanism of the reaction has been determined. Importantly, we have discovered that the cobalt catalysts described here give distinctive selectivities that are better than known catalysts. These selectivities come from a synergy between supporting ligand design and electronic control of the spin-state crossing in the reactions.

  15. Spin labels. Applications in biology

    International Nuclear Information System (INIS)

    Frangopol, T.P.; Frangopol, M.; Ionescu, S.M.; Pop, I.V.; Benga, G.

    1980-11-01

    The main applications of spin labels in the study of biomembranes, enzymes, nucleic acids, in pharmacology, spin immunoassay are reviewed along with the fundamentals of the spin label method. 137 references. (author)

  16. Efficient spin filter using multi-terminal quantum dot with spin-orbit interaction

    Directory of Open Access Journals (Sweden)

    Yokoyama Tomohiro

    2011-01-01

    Full Text Available Abstract We propose a multi-terminal spin filter using a quantum dot with spin-orbit interaction. First, we formulate the spin Hall effect (SHE in a quantum dot connected to three leads. We show that the SHE is significantly enhanced by the resonant tunneling if the level spacing in the quantum dot is smaller than the level broadening. We stress that the SHE is tunable by changing the tunnel coupling to the third lead. Next, we perform a numerical simulation for a multi-terminal spin filter using a quantum dot fabricated on semiconductor heterostructures. The spin filter shows an efficiency of more than 50% when the conditions for the enhanced SHE are satisfied. PACS numbers: 72.25.Dc,71.70.Ej,73.63.Kv,85.75.-d

  17. Nuclear spin polarization of targets

    International Nuclear Information System (INIS)

    Happer, W.

    1990-01-01

    Lasers can be used to produce milligrams to grams of noble gas nuclei with spin polarizations in excess of 50%. These quantities are sufficient to be very useful targets in nuclear physics experiments. Alkali-metal atoms are used to capture the angular momentum of circularly polarized laser photons, and the alkali-metal atoms transfer their angular momentum to noble gas atoms in binary or three-body collisions. Non-radiative collisions between the excited alkali atoms and molecular quenching gases are essential to avoid radiation trapping. The spin exchange can involve gas-phase van der Waals molecules, consisting of a noble gas atom and an alkali metal atom. Surface chemistry is also of great importance in determining the wall-induced relaxation rates of the noble gases

  18. Changes in vaginal breech delivery rates in a single large metropolitan area.

    LENUS (Irish Health Repository)

    Hehir, Mark P

    2012-06-01

    Vaginal breech delivery rates have been accepted widely to be in decline and the Term Breech Trial (TBT) has recommended delivery of a breech-presenting infant by elective cesarean section delivery. Our aim was to examine the rate of vaginal delivery of term breech pregnancies in the 8 years before and after the publication of the TBT.

  19. Changes in Blood Pressure and Heart Rate during Fixed-Interval Responding in Squirrel Monkeys

    Science.gov (United States)

    DeWeese, Jo

    2009-01-01

    Episodic and sustained increases in heart rate and mean arterial blood pressure can occur with recurring patterns of schedule-controlled behavior. Most previous studies were conducted under fixed-ratio schedules, which maintained a consistent high rate of responding that alternated with periods of no responding during times when the schedule was…

  20. Spin Switching via Quantum Dot Spin Valves

    Science.gov (United States)

    Gergs, N. M.; Bender, S. A.; Duine, R. A.; Schuricht, D.

    2018-01-01

    We develop a theory for spin transport and magnetization dynamics in a quantum dot spin valve, i.e., two magnetic reservoirs coupled to a quantum dot. Our theory is able to take into account effects of strong correlations. We demonstrate that, as a result of these strong correlations, the dot gate voltage enables control over the current-induced torques on the magnets and, in particular, enables voltage-controlled magnetic switching. The electrical resistance of the structure can be used to read out the magnetic state. Our model may be realized by a number of experimental systems, including magnetic scanning-tunneling microscope tips and artificial quantum dot systems.