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Sample records for 1st order autocorrelation

  1. 1st- and 2nd-order motion and texture resolution in central and peripheral vision

    NASA Technical Reports Server (NTRS)

    Solomon, J. A.; Sperling, G.

    1995-01-01

    STIMULI. The 1st-order stimuli are moving sine gratings. The 2nd-order stimuli are fields of static visual texture, whose contrasts are modulated by moving sine gratings. Neither the spatial slant (orientation) nor the direction of motion of these 2nd-order (microbalanced) stimuli can be detected by a Fourier analysis; they are invisible to Reichardt and motion-energy detectors. METHOD. For these dynamic stimuli, when presented both centrally and in an annular window extending from 8 to 10 deg in eccentricity, we measured the highest spatial frequency for which discrimination between +/- 45 deg texture slants and discrimination between opposite directions of motion were each possible. RESULTS. For sufficiently low spatial frequencies, slant and direction can be discriminated in both central and peripheral vision, for both 1st- and for 2nd-order stimuli. For both 1st- and 2nd-order stimuli, at both retinal locations, slant discrimination is possible at higher spatial frequencies than direction discrimination. For both 1st- and 2nd-order stimuli, motion resolution decreases 2-3 times more rapidly with eccentricity than does texture resolution. CONCLUSIONS. (1) 1st- and 2nd-order motion scale similarly with eccentricity. (2) 1st- and 2nd-order texture scale similarly with eccentricity. (3) The central/peripheral resolution fall-off is 2-3 times greater for motion than for texture.

  2. Distributions of Autocorrelated First-Order Kinetic Outcomes: Illness Severity

    PubMed Central

    Englehardt, James D.

    2015-01-01

    Many complex systems produce outcomes having recurring, power law-like distributions over wide ranges. However, the form necessarily breaks down at extremes, whereas the Weibull distribution has been demonstrated over the full observed range. Here the Weibull distribution is derived as the asymptotic distribution of generalized first-order kinetic processes, with convergence driven by autocorrelation, and entropy maximization subject to finite positive mean, of the incremental compounding rates. Process increments represent multiplicative causes. In particular, illness severities are modeled as such, occurring in proportion to products of, e.g., chronic toxicant fractions passed by organs along a pathway, or rates of interacting oncogenic mutations. The Weibull form is also argued theoretically and by simulation to be robust to the onset of saturation kinetics. The Weibull exponential parameter is shown to indicate the number and widths of the first-order compounding increments, the extent of rate autocorrelation, and the degree to which process increments are distributed exponential. In contrast with the Gaussian result in linear independent systems, the form is driven not by independence and multiplicity of process increments, but by increment autocorrelation and entropy. In some physical systems the form may be attracting, due to multiplicative evolution of outcome magnitudes towards extreme values potentially much larger and smaller than control mechanisms can contain. The Weibull distribution is demonstrated in preference to the lognormal and Pareto I for illness severities versus (a) toxicokinetic models, (b) biologically-based network models, (c) scholastic and psychological test score data for children with prenatal mercury exposure, and (d) time-to-tumor data of the ED01 study. PMID:26061263

  3. 26. Photograph of original Fresnel lens a 1st order fixed ...

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

    26. Photograph of original Fresnel lens a 1st order fixed white light. (Installed 1874 and first illuminated Feb. 1, 1875. This is the only known photograph of this lens - - removed in 1929.)ca. 1918. - Block Island Southeast Light, Spring Street & Mohegan Trail at Mohegan Bluffs, New Shoreham, Washington County, RI

  4. Magnetic field induced 1st order transitions: Recent studies, and some new concepts

    NASA Astrophysics Data System (ADS)

    Chaddah, P.

    2015-05-01

    Phase transitions are caused by varying temperature, or pressure, or magnetic field. The observation of 1st order magneto-structural transitions has created application possibilities based on magnetoresistance, magnetocaloric effect, magnetic shape memory effect, and magneto-dielectric effect. Magnetic field induced transitions, and phase coexistence of competing magnetic phases down to the lowest temperature, gained prominence over a decade ago with theoretical models suggesting that the ground state is not homogeneous. Researchers at Indore pushed an alternative view that this phase coexistence could be due to glasslike "kinetic arrest" of a disorder-broadened first-order magnetic transition between two states with long-range magnetic order, resulting in phase coexistence down to the lowest temperatures. The CHUF (cooling and heating in unequal field) protocol created at Indore allows the observation of `devitrification', followed by `melting'. I show examples of measurements establishing kinetic arrest in various materials, emphasizing that glasslike arrest of 1st order magnetic transitions may be as ubiquitous as glass formation following the arrest of 1st order structural transitions.

  5. Dimensionality dependence of aging in kinetics of diffusive phase separation: Behavior of order-parameter autocorrelation

    NASA Astrophysics Data System (ADS)

    Midya, Jiarul; Majumder, Suman; Das, Subir K.

    2015-08-01

    Behavior of two-time autocorrelation during the phase separation in solid binary mixtures is studied via numerical solutions of the Cahn-Hilliard equation as well as Monte Carlo simulations of the Ising model. Results are analyzed via state-of-the-art methods, including the finite-size scaling technique. Full forms of the autocorrelation in space dimensions 2 and 3 are obtained empirically. The long-time behavior is found to be power law, with exponents unexpectedly higher than the ones for the ferromagnetic ordering. Both Cahn-Hilliard and Ising models provide consistent results.

  6. Second-order fluctuation theory and time autocorrelation function for currents

    NASA Astrophysics Data System (ADS)

    Belousov, Roman; Cohen, E. G. D.

    2016-12-01

    By using recent developments for the Langevin dynamics of spatially asymmetric systems, we routinely generalize the Onsager-Machlup fluctuation theory of the second order in time. In this form, it becomes applicable to fluctuating variables, including hydrodynamic currents, in equilibrium as well as nonequilibrium steady states. From the solution of the obtained stochastic equations we derive an analytical expression for the time autocorrelation function of a general fluctuating quantity. This theoretical result is then tested in a study of a shear flow by molecular dynamics simulations. The proposed form of the time autocorrelation function yields an excellent fit to our computational data for both equilibrium and nonequilibrium steady states. Unlike the analogous result of the first-order Onsager-Machlup theory, our expression correctly describes the short-time correlations. Its utility is demonstrated in an application of the Green-Kubo formula for the transport coefficient. Curiously, the normalized time autocorrelation function for the shear flow, which only depends on the deterministic part of the fluctuation dynamics, appears independent of the external shear force in the linear nonequilibrium regime.

  7. CO2 dynamics in nested catchments: a longitudinal perspective from soil to 1st and 2nd order streams

    NASA Astrophysics Data System (ADS)

    Johnson, M. S.; Lehmann, J.; Riha, S. J.; Couto, E. G.

    2005-12-01

    Fluxes of CO2 from terrestrial to aquatic environments were investigated in a nested catchment study in the seasonally-dry southern Amazon. Dissolved CO2 concentrations in groundwater springs, four 1st order streams and one 2nd order stream were determined via routine sampling and in-situ monitoring. CO2 concentrations were monitored in the soil atmosphere to 8m. Belowground, the seasonal trend in soil CO2 concentrations at depth lagged that of seasonal water table dynamics, with peak concentrations (8.7% CO2 vol/vol at 4m) occurring one month after maximum water table height, indicating a shift in root respiration and plant water uptake to deeper soil layers during the dry season. Peak dissolved CO2 concentrations in springs and streams lagged the soil CO2 maximum by an additional month. During storm events, streamflow CO2 concentrations were found to decrease initially, reflecting the initial contribution of low-CO2 direct precipitation and surface runoff. Streamwater CO2 then increased as the contribution of pre-event water to storm flow increased. Dissolved CO2 in springs was also found to increase during storm events. Diurnal fluctuations in dissolved CO2 of springs were also observed, indicating the connectivity of the biosphere, pedosphere and hydrosphere for headwater catchments. The dissolved CO2 concentration within 1st order streams decreases rapidly downstream from stream sources, with spring CO2 concentration 3.3 times that at headwater catchment outlets. This initial outgassing of CO2 within 1st order streams was found to be accompanied by a corresponding increase in the pH of stream water. However, dissolved CO2 concentrations were not found to be significantly different between 1st and 2nd order streams. This suggests a discontinuity between some processes at the terrestrial-aquatic interface in headwater catchments and those of larger-order watersheds.

  8. Hybrid distributed Raman amplification combining random fiber laser based 2nd-order and low-noise LD based 1st-order pumping.

    PubMed

    Jia, Xin-Hong; Rao, Yun-Jiang; Yuan, Cheng-Xu; Li, Jin; Yan, Xiao-Dong; Wang, Zi-Nan; Zhang, Wei-Li; Wu, Han; Zhu, Ye-Yu; Peng, Fei

    2013-10-21

    A configuration of hybrid distributed Raman amplification (H-DRA), that is formed by incorporating a random fiber laser (RFL) based 2nd-order pump and a low-noise laser-diode (LD) based 1st-order pump, is proposed in this paper. In comparison to conventional bi-directional 1st-order DRA, the effective noise figure (ENF) is found to be lower by amount of 0 to 4 dB due to the RFL-based 2nd-order pump, depending on the on-off gain, while the low-noise 1st-order Raman pump is used for compensating the worsened signal-to-noise ratio (SNR) in the vicinity towards the far end of the fiber and avoiding the potential nonlinear impact induced by excess injection of pump power and suppressing the pump-signal relative intensity noise (RIN) transfer. As a result, the gain distribution can be optimized along ultra-long fiber link, due to combination of the 2nd-order RFL and low-noise 1st-order pumping, making the transmission distance be extended significantly. We utilized such a configuration to achieve ultra-long-distance distributed sensing based on Brillouin optical time-domain analysis (BOTDA). A repeater-less sensing distance record of up to 154.4 km with 5 m spatial resolution and ~ ± 1.4 °C temperature uncertainty is successfully demonstrated.

  9. The Viability of Phantom Dark Energy as a Quantum Field in 1st-Order FLRW Space

    NASA Astrophysics Data System (ADS)

    Ludwick, Kevin

    2017-01-01

    In the standard cosmological framework of the 0th-order FLRW metric and the use of perfect fluids in the stress-energy tensor, dark energy with an equation-of-state parameter w < - 1 (known as phantom dark energy) implies negative kinetic energy and vacuum instability when modeled as a scalar field. However, the accepted values for present-day w from Planck and WMAP9 include a significant range of values less than - 1 . We consider a more accurate description of the universe through the 1st-order perturbing of the isotropic and homogeneous FLRW metric and the components of the stress-energy tensor and investigate whether a field with an apparent w < - 1 may still have positive kinetic energy. Treating dark energy as a classical scalar field in this metric, we find that it is not as obvious as one might think that phantom dark energy has negative kinetic energy categorically. Analogously, we find that field models of quintessence dark energy (w > - 1) do not necessarily have positive kinetic energy categorically. We then investigate the same question treating dark energy as a quantum field in 1st-order FLRW space-time and examining the expectation value of the stress-energy tensor for w < - 1 using adiabatic expansion.

  10. Detection of 1st- and 2nd-order temporal-envelope cues in a patient with left superior cortical damage.

    PubMed

    Füllgrabe, Christian; Maillet, Didier; Moroni, Christine; Belin, Catherine; Lorenzi, Christian

    2004-06-01

    This psychophysical study explores the extent to which the auditory cortex is necessary for various aspects of temporal-envelope perception, that is, perception of the slow temporal modulations in amplitude known to be crucial for sound identification. The ability to detect 1st- and 2nd-order sinusoidal amplitude modulation (AM) is evaluated in a single patient showing left-hemisphere damage encroaching the primary and secondary auditory cortices. Here, 1st- and 2nd-order AM refer to (1) sinusoidal variation in the amplitude of a 2 kHz pure tone, and (2) sinusoidal variation in the depth of a 64 Hz AM applied to the 2 kHz pure tone, respectively. The results replicate previous findings by showing that damage to the left auditory cortex results in a selective deficit in auditory sensitivity to the lowest 1St-order AM (i.e., 1st-order AM frequencies < 16 Hz). Moreover, a dissociation is apparent between the ability to detect 1st- and 2nd-order temporal-envelope cues. The patient shows poorer than normal ability to detect 2nd-order AM at low frequencies ranging from 4-23 Hz, but normal ability to detect the high (64 Hz) 1st-order AM carrying these 2nd-order modulations. This result indicates that damage to the left primary and secondary auditory cortices affects the ability to detect temporal variations in the local properties of sounds(such as AM depth). It is also consistent with the idea that, as in vision, central nonlinear mechanisms are involved in the computation of such local (or 2nd-order) temporal properties.

  11. Experimental observations on the response of 1(st) and 2(nd) order fibre optic long period grating coupling bands to the deposition of nanostructured coatings.

    PubMed

    James, Stephen W; Cheung, C S; Tatam, Ralph P

    2007-10-01

    The sensitivity of attenuation bands corresponding to the 2(nd) order coupling to cladding modes by a fibre optic long period grating (LPG) to the deposition of nanostructured coatings is investigated and compared with that of the 1(st) order coupling. The experimental observations support previously reported theoretical descriptions of LPGs with nanoscale coatings.

  12. All-optical 1st- and 2nd-order differential equation solvers with large tuning ranges using Fabry-Pérot semiconductor optical amplifiers.

    PubMed

    Chen, Kaisheng; Hou, Jie; Huang, Zhuyang; Cao, Tong; Zhang, Jihua; Yu, Yuan; Zhang, Xinliang

    2015-02-09

    We experimentally demonstrate an all-optical temporal computation scheme for solving 1st- and 2nd-order linear ordinary differential equations (ODEs) with tunable constant coefficients by using Fabry-Pérot semiconductor optical amplifiers (FP-SOAs). By changing the injection currents of FP-SOAs, the constant coefficients of the differential equations are practically tuned. A quite large constant coefficient tunable range from 0.0026/ps to 0.085/ps is achieved for the 1st-order differential equation. Moreover, the constant coefficient p of the 2nd-order ODE solver can be continuously tuned from 0.0216/ps to 0.158/ps, correspondingly with the constant coefficient q varying from 0.0000494/ps(2) to 0.006205/ps(2). Additionally, a theoretical model that combining the carrier density rate equation of the semiconductor optical amplifier (SOA) with the transfer function of the Fabry-Pérot (FP) cavity is exploited to analyze the solving processes. For both 1st- and 2nd-order solvers, excellent agreements between the numerical simulations and the experimental results are obtained. The FP-SOAs based all-optical differential-equation solvers can be easily integrated with other optical components based on InP/InGaAsP materials, such as laser, modulator, photodetector and waveguide, which can motivate the realization of the complicated optical computing on a single integrated chip.

  13. A liver cirrhosis classification on B-mode ultrasound images by the use of higher order local autocorrelation features

    NASA Astrophysics Data System (ADS)

    Sasaki, Kenya; Mitani, Yoshihiro; Fujita, Yusuke; Hamamoto, Yoshihiko; Sakaida, Isao

    2017-02-01

    In this paper, in order to classify liver cirrhosis on regions of interest (ROIs) images from B-mode ultrasound images, we have proposed to use the higher order local autocorrelation (HLAC) features. In a previous study, we tried to classify liver cirrhosis by using a Gabor filter based approach. However, the classification performance of the Gabor feature was poor from our preliminary experimental results. In order accurately to classify liver cirrhosis, we examined to use the HLAC features for liver cirrhosis classification. The experimental results show the effectiveness of HLAC features compared with the Gabor feature. Furthermore, by using a binary image made by an adaptive thresholding method, the classification performance of HLAC features has improved.

  14. 1st and 2nd order Raman scattering from n-Graphene Layer (nGL) Films on Silicon Substrates.

    NASA Astrophysics Data System (ADS)

    Gupta, Awnish; Chen, Gugang; Eklund, Peter

    2007-03-01

    Results of room temperature Raman scattering experiments on graphene and n-graphene layer films (nGLs) will be presented [1]. We find that the G band at ˜ 1582 cm-1 exhibits an interesting upshift in frequency with 1/n which we tentatively assign to a surface strain phenomenon connected with surface roughness of the substrate and compensated by the increase in stiffness of the nGL with increasing n. Interesting n-specific bands are observed in the ˜1350 cm-1 (or D-band) region which may correlate with deviations from planarity of the nGL. The second order scattering is very interesting and for small n (n<4) the (2D' or G') band intensity at ˜ 2700 cm-1 is actually higher than the first-order G-band scattering. The shape of this band is sensitive to n and thus can be used to identify n without an AFM measurement. Whereas, the 2D' band is sensitive to n, the 2nd order 2G band ˜ 3248 cm-1 is independent of n. These observations will be discussed in terms of the phonon and electronic dispersion of nGLs. 1 A. Gupta, G. Chen, P. Joshi, S. Tadigadapa and P.C. Eklund, `` Raman Scattering from High-Frequency Phonons in Supported n-Graphene Layer Films'' NanoLett (in Press).

  15. Signal processing of MEMS gyroscope arrays to improve accuracy using a 1st order Markov for rate signal modeling.

    PubMed

    Jiang, Chengyu; Xue, Liang; Chang, Honglong; Yuan, Guangmin; Yuan, Weizheng

    2012-01-01

    This paper presents a signal processing technique to improve angular rate accuracy of the gyroscope by combining the outputs of an array of MEMS gyroscope. A mathematical model for the accuracy improvement was described and a Kalman filter (KF) was designed to obtain optimal rate estimates. Especially, the rate signal was modeled by a first-order Markov process instead of a random walk to improve overall performance. The accuracy of the combined rate signal and affecting factors were analyzed using a steady-state covariance. A system comprising a six-gyroscope array was developed to test the presented KF. Experimental tests proved that the presented model was effective at improving the gyroscope accuracy. The experimental results indicated that six identical gyroscopes with an ARW noise of 6.2 °/√h and a bias drift of 54.14 °/h could be combined into a rate signal with an ARW noise of 1.8 °/√h and a bias drift of 16.3 °/h, while the estimated rate signal by the random walk model has an ARW noise of 2.4 °/√h and a bias drift of 20.6 °/h. It revealed that both models could improve the angular rate accuracy and have a similar performance in static condition. In dynamic condition, the test results showed that the first-order Markov process model could reduce the dynamic errors 20% more than the random walk model.

  16. Nonlinear random motion analysis of coupled heave-pitch motions of a spar platform considering 1st-order and 2nd-order wave loads

    NASA Astrophysics Data System (ADS)

    Liu, Shuxiao; Tang, Yougang; Li, Wei

    2016-06-01

    In this study, we consider first- and second-order random wave loads and the effects of time-varying displacement volume and transient wave elevation to establish motion equations of the Spar platform's coupled heave-pitch. We generated random wave loads based on frequency-domain wave load transfer functions and the Joint North Sea Wave Project (JONSWAP) wave spectrum, designed program codes to solve the motion equations, and then simulated the coupled heave-pitch motion responses of the platform in the time domain. We then calculated and compared the motion responses in different sea conditions and separately investigated the effects of second-order random wave loads and transient wave elevation. The results show that the coupled heave-pitch motion responses of the platform are primarily dominated by wave height and the characteristic wave period, the latter of which has a greater impact. Second-order mean wave loads mainly affect the average heave value. The platform's pitch increases after the second-order low frequency wave loads are taken into account. The platform's heave is underestimated if the transient wave elevation term in the motion equations is neglected.

  17. The truncated Newton using 1st and 2nd order adjoint-state method: a new approach for traveltime tomography without rays

    NASA Astrophysics Data System (ADS)

    Bretaudeau, F.; Metivier, L.; Brossier, R.; Virieux, J.

    2013-12-01

    named as the truncated Newton (TCN) (Métivier et al. 2012) with a more accurate estimation of the impact of the Hessian. We propose an efficient implementation for first-arrival traveltime tomography. In TCN, the model update Δm is obtained through the iterative resolution of the Newton linear system H Δm = - g. Based on a matrix-free conjugate gradient resolution, the iterative solver requires only the computation of the gradient and of Hessian-vector products. We propose a generalization of the computation of the gradient using the adjoint-state method that allows to consider receivers located anywhere. Then the Hessian-vector products are computed using an original formulation based on a 2nd-order adjoint-state method, at the cost of an additional forward modeling. The TCN algorithm is composed of two nested loops: an internal loop to compute Δm, and an external loop where a line search is performed to update the subsurface parameters. TCN thus considers locally the inversion of the traveltime data using an estimation of the full Hessian (both 1st and 2nd order terms) at an acceptable cost. Tomography with TCN is an improvement over the simple gradient-based adjoint-state tomography due to its good convergence property, to the better consideration of illumination, and is a promising tool for multi-parameter inversion as rescaling is given by the Hessian.

  18. Parallel auto-correlative statistics with VTK.

    SciTech Connect

    Pebay, Philippe Pierre; Bennett, Janine Camille

    2013-08-01

    This report summarizes existing statistical engines in VTK and presents both the serial and parallel auto-correlative statistics engines. It is a sequel to [PT08, BPRT09b, PT09, BPT09, PT10] which studied the parallel descriptive, correlative, multi-correlative, principal component analysis, contingency, k-means, and order statistics engines. The ease of use of the new parallel auto-correlative statistics engine is illustrated by the means of C++ code snippets and algorithm verification is provided. This report justifies the design of the statistics engines with parallel scalability in mind, and provides scalability and speed-up analysis results for the autocorrelative statistics engine.

  19. Semiclassical description of autocorrelations in nuclear masses

    SciTech Connect

    Garcia-Garcia, Antonio M.; Hirsch, Jorge G.; Frank, Alejandro

    2006-08-15

    Nuclear mass autocorrelations are investigated as a function of the number of nucleons. The fluctuating part of these autocorrelations is modeled by a parameter free model in which the nucleons are confined in a rigid sphere. Explicit results are obtained by using periodic orbit theory. Despite the simplicity of the model we have found a remarkable quantitative agreement of the mass autocorrelations for all nuclei in the nuclear data chart. In order to achieve a similar degree of agreement for the nuclear masses themselves it is necessary to consider additional variables such as multipolar corrections to the spherical shape and an effective number of nucleons. Our findings suggest that higher order effects like nuclear deformations or residual interactions have little relevance in the description of the fluctuations of the nuclear autocorrelations.

  20. Low autocorrelation binary sequences

    NASA Astrophysics Data System (ADS)

    Packebusch, Tom; Mertens, Stephan

    2016-04-01

    Binary sequences with minimal autocorrelations have applications in communication engineering, mathematics and computer science. In statistical physics they appear as groundstates of the Bernasconi model. Finding these sequences is a notoriously hard problem, that so far can be solved only by exhaustive search. We review recent algorithms and present a new algorithm that finds optimal sequences of length N in time O(N {1.73}N). We computed all optimal sequences for N≤slant 66 and all optimal skewsymmetric sequences for N≤slant 119.

  1. Modeling Covariance Matrices via Partial Autocorrelations

    PubMed Central

    Daniels, M.J.; Pourahmadi, M.

    2009-01-01

    Summary We study the role of partial autocorrelations in the reparameterization and parsimonious modeling of a covariance matrix. The work is motivated by and tries to mimic the phenomenal success of the partial autocorrelations function (PACF) in model formulation, removing the positive-definiteness constraint on the autocorrelation function of a stationary time series and in reparameterizing the stationarity-invertibility domain of ARMA models. It turns out that once an order is fixed among the variables of a general random vector, then the above properties continue to hold and follows from establishing a one-to-one correspondence between a correlation matrix and its associated matrix of partial autocorrelations. Connections between the latter and the parameters of the modified Cholesky decomposition of a covariance matrix are discussed. Graphical tools similar to partial correlograms for model formulation and various priors based on the partial autocorrelations are proposed. We develop frequentist/Bayesian procedures for modelling correlation matrices, illustrate them using a real dataset, and explore their properties via simulations. PMID:20161018

  2. Electric field autocorrelation functions for beginning multiple rayleigh scattering.

    PubMed

    Lock, J A

    2001-08-20

    The polarization-resolved electric field autocorrelation function for p-order scattering was derived from the order-of-scattering solution of the exact equations for electromagnetic multiple Rayleigh scattering and was calculated for 2 order autocorrelation function approximately decoupled from the delay-time dependence for p ? 3. The polarization-channel and the scattering-angle dependence were analytically calculated, and the delay-time dependence was analytically approximated. The resulting analytical model for the polarization-resolved autocorrelation function for beginning multiple Rayleigh scattering was then tested against experimental autocorrelation data. The data were found to be well fitted by the model.

  3. Electric Field Autocorrelation Functions for Beginning Multiple Rayleigh Scattering

    NASA Astrophysics Data System (ADS)

    Lock, James A.

    2001-08-01

    The polarization-resolved electric field autocorrelation function for p -order scattering was derived from the order-of-scattering solution of the exact equations for electromagnetic multiple Rayleigh scattering and was calculated for 2 p 6 for particles undergoing diffusive motion in an idealized sample cell. It was found that the polarization-channel and the scattering-angle dependence of the p -order autocorrelation function approximately decoupled from the delay-time dependence for p ~ 3 . The polarization-channel and the scattering-angle dependence were analytically calculated, and the delay-time dependence was analytically approximated. The resulting analytical model for the polarization-resolved autocorrelation function for beginning multiple Rayleigh scattering was then tested against experimental autocorrelation data. The data were found to be well fitted by the model.

  4. "Hard Science" for Gifted 1st Graders

    ERIC Educational Resources Information Center

    DeGennaro, April

    2006-01-01

    "Hard Science" is designed to teach 1st grade gifted students accurate and high level science concepts. It is based upon their experience of the world and attempts to build a foundation for continued love and enjoyment of science. "Hard Science" provides field experiences and opportunities for hands-on discovery working beside experts in the field…

  5. A simple method to estimate interwell autocorrelation

    SciTech Connect

    Pizarro, J.O.S.; Lake, L.W.

    1997-08-01

    The estimation of autocorrelation in the lateral or interwell direction is important when performing reservoir characterization studies using stochastic modeling. This paper presents a new method to estimate the interwell autocorrelation based on parameters, such as the vertical range and the variance, that can be estimated with commonly available data. We used synthetic fields that were generated from stochastic simulations to provide data to construct the estimation charts. These charts relate the ratio of areal to vertical variance and the autocorrelation range (expressed variously) in two directions. Three different semivariogram models were considered: spherical, exponential and truncated fractal. The overall procedure is demonstrated using field data. We find that the approach gives the most self-consistent results when it is applied to previously identified facies. Moreover, the autocorrelation trends follow the depositional pattern of the reservoir, which gives confidence in the validity of the approach.

  6. SU(3) lattice gauge autocorrelations with anisotropic action

    NASA Astrophysics Data System (ADS)

    Draper, Terrence; Nenkov, Constantine; Peardon, Mike

    1997-02-01

    We report results of autocorrelation measurements in pure SU(3) lattice gauge theory. The computations are performed on the CONVEX SPP1200 parallel platform within the CANOPY programming environment. The focus of our analysis is on typical autocorrelation times and optimization of the mixing ratio between overrelaxation and pseudo-heatbath sweeps for generating gauge field configurations. We study second order tadpole-improved approximation of the Wilson action in the gluon sector, which offers the advantage on smaller lattices (8 3 × 16 and 6 3 × 12 - 30). We also make use of anisotropic lattices, with temporal lattice spacing smaller than the spatial spacing, which prove useful for calculating noisy correlation functions with large spatial lattice discretization (of the order of 0.4 fm).

  7. Bayesian Estimates of Autocorrelations in Single-Case Designs

    ERIC Educational Resources Information Center

    Shadish, William R.; Rindskopf, David M.; Hedges, Larry V.; Sullivan, Kristynn J.

    2012-01-01

    Researchers in the single-case design tradition have debated the size and importance of the observed autocorrelations in those designs. All of the past estimates of the autocorrelation in that literature have taken the observed autocorrelation estimates as the data to be used in the debate. However, estimates of the autocorrelation are subject to…

  8. Droplet model for autocorrelation functions in an Ising ferromagnet

    NASA Technical Reports Server (NTRS)

    Tang, Chao; Nakanishi, Hiizu; Langer, J. S.

    1989-01-01

    The autocorrelation function of Ising spins in an ordered phase is studied via a droplet model. Only noninteracting spherical droplets are considered. The Langevin equation which describes fluctuations in the radius of a single droplet is studied in detail. A general description of the transformation to a Fokker-Planck equations and the ways in which a spectral analysis of that equation can be used to compute the autocorrelation function is given. It is shown that the eigenvalues of the Fokker-Planck operator form (1) a continuous spectrum of relaxation rates starting from zero for d = 2, (2) a continuous spectrum with a finite gap for d = 3, and (3) a discrete spectrum for d greater than 4, where d is the spatial dimensionality. Detailed solutions for various cases are presented.

  9. Correlations of correlations: Secondary autocorrelations in finite harmonic systems.

    PubMed

    Plyukhin, Dan; Plyukhin, Alex V

    2015-10-01

    The momentum or velocity autocorrelation function C(t) for a tagged oscillator in a finite harmonic system decays like that of an infinite system for short times, but exhibits erratic behavior at longer time scales. We introduce the autocorrelation function of the long-time noisy tail of C(t) ("a correlation of the correlation"), which characterizes the distribution of recurrence times. Remarkably, for harmonic systems with same-mass particles this secondary correlation may coincide with the primary correlation C(t) (when both functions are normalized) either exactly, or over a significant initial time interval. When the tagged particle is heavier than the rest, the equality does not hold, correlations show nonrandom long-time scale pattern, and higher-order correlations converge to the lowest normal mode.

  10. EMSL Quarterly Highlights Report: 1st Quarter, FY08

    SciTech Connect

    Showalter, Mary Ann

    2008-01-28

    The EMSL Quarterly Highlights Report covers the science, staff and user recognition, and publication activities that occurred during the 1st quarter (October 2007 - December 2007) of Fiscal Year 2008.

  11. ISS Update: 1st Annual ISS R&D Conference

    NASA Video Gallery

    NASA Public Affairs Officer Kelly Humphries talks by phone on Wednesday with Julie Robinson, ISS Program Scientist, about the 1st Annual International Space Station Research and Development Confere...

  12. EMSL Quarterly Highlights Report: 1st Quarter, Fiscal Year 2009

    SciTech Connect

    Showalter, Mary Ann; Kathmann, Loel E.; Manke, Kristin L.

    2009-02-02

    The EMSL Quarterly Highlights Report covers the science, staff and user recognition, and publication activities that occurred during the 1st quarter (October 2008 - December 2008) of Fiscal Year 2009.

  13. Electronic Health Records Place 1st at Indy 500

    MedlinePlus

    ... Navigation Bar Home Current Issue Past Issues EHR Electronic Health Records Place 1st at Indy 500 Past ... last May's Indy 500 had thousands of personal Electronic Health Records on hand for those attending—and ...

  14. An autocorrelator based on a Fabry-Perot interferometer.

    PubMed

    An, Jungkwuen; Pyun, Kyungsuk; Kwon, Ojoon; Kim, Dong Eon

    2013-01-14

    An autocorrelator based on a Fabry-Perot interferometer is proposed for ultrashort pulse measurement. Main features of this autocorrelator due to the superposition of multiple pulses were investigated experimentally and theoretically. It turns out that the signal from a Fabry-Perot interferometer can be used as an autocorrelator signal. This autocorrelator provides more compact setup with a much easier alignment than a conventional autocorrelator based on a Michelson interferometer.

  15. An Overdetermined System for Improved Autocorrelation Based Spectral Moment Estimator Performance

    NASA Technical Reports Server (NTRS)

    Keel, Byron M.

    1996-01-01

    Autocorrelation based spectral moment estimators are typically derived using the Fourier transform relationship between the power spectrum and the autocorrelation function along with using either an assumed form of the autocorrelation function, e.g., Gaussian, or a generic complex form and applying properties of the characteristic function. Passarelli has used a series expansion of the general complex autocorrelation function and has expressed the coefficients in terms of central moments of the power spectrum. A truncation of this series will produce a closed system of equations which can be solved for the central moments of interest. The autocorrelation function at various lags is estimated from samples of the random process under observation. These estimates themselves are random variables and exhibit a bias and variance that is a function of the number of samples used in the estimates and the operational signal-to-noise ratio. This contributes to a degradation in performance of the moment estimators. This dissertation investigates the use autocorrelation function estimates at higher order lags to reduce the bias and standard deviation in spectral moment estimates. In particular, Passarelli's series expansion is cast in terms of an overdetermined system to form a framework under which the application of additional autocorrelation function estimates at higher order lags can be defined and assessed. The solution of the overdetermined system is the least squares solution. Furthermore, an overdetermined system can be solved for any moment or moments of interest and is not tied to a particular form of the power spectrum or corresponding autocorrelation function. As an application of this approach, autocorrelation based variance estimators are defined by a truncation of Passarelli's series expansion and applied to simulated Doppler weather radar returns which are characterized by a Gaussian shaped power spectrum. The performance of the variance estimators determined

  16. General simulation algorithm for autocorrelated binary processes

    NASA Astrophysics Data System (ADS)

    Serinaldi, Francesco; Lombardo, Federico

    2017-02-01

    The apparent ubiquity of binary random processes in physics and many other fields has attracted considerable attention from the modeling community. However, generation of binary sequences with prescribed autocorrelation is a challenging task owing to the discrete nature of the marginal distributions, which makes the application of classical spectral techniques problematic. We show that such methods can effectively be used if we focus on the parent continuous process of beta distributed transition probabilities rather than on the target binary process. This change of paradigm results in a simulation procedure effectively embedding a spectrum-based iterative amplitude-adjusted Fourier transform method devised for continuous processes. The proposed algorithm is fully general, requires minimal assumptions, and can easily simulate binary signals with power-law and exponentially decaying autocorrelation functions corresponding, for instance, to Hurst-Kolmogorov and Markov processes. An application to rainfall intermittency shows that the proposed algorithm can also simulate surrogate data preserving the empirical autocorrelation.

  17. Spectra of empirical autocorrelation matrices: A random-matrix-theory-inspired perspective

    NASA Astrophysics Data System (ADS)

    Jamali, Tayeb; Jafari, G. R.

    2015-07-01

    We construct an autocorrelation matrix of a time series and analyze it based on the random-matrix theory (RMT) approach. The autocorrelation matrix is capable of extracting information which is not easily accessible by the direct analysis of the autocorrelation function. In order to provide a precise conclusion based on the information extracted from the autocorrelation matrix, the results must be first evaluated. In other words they need to be compared with some sort of criterion to provide a basis for the most suitable and applicable conclusions. In the context of the present study, the criterion is selected to be the well-known fractional Gaussian noise (fGn). We illustrate the applicability of our method in the context of stock markets. For the former, despite the non-Gaussianity in returns of the stock markets, a remarkable agreement with the fGn is achieved.

  18. Constant-Envelope Waveform Design for Optimal Target-Detection and Autocorrelation Performances

    SciTech Connect

    Sen, Satyabrata

    2013-01-01

    We propose an algorithm to directly synthesize in time-domain a constant-envelope transmit waveform that achieves the optimal performance in detecting an extended target in the presence of signal-dependent interference. This approach is in contrast to the traditional indirect methods that synthesize the transmit signal following the computation of the optimal energy spectral density. Additionally, we aim to maintain a good autocorrelation property of the designed signal. Therefore, our waveform design technique solves a bi-objective optimization problem in order to simultaneously improve the detection and autocorrelation performances, which are in general conflicting in nature. We demonstrate this compromising characteristics of the detection and autocorrelation performances with numerical examples. Furthermore, in the absence of the autocorrelation criterion, our designed signal is shown to achieve a near-optimum detection performance.

  19. Wavefront autocorrelation of femtosecond laser beams

    NASA Astrophysics Data System (ADS)

    Grunwald, Ruediger; Neumann, Uwe J.; Griebner, Uwe; Reimann, Klaus; Steinmeyer, Guenter; Kebbel, Volker

    2004-06-01

    Spatially resolved wavefront sensing and time-resolved autocorrelation measurement of ultrashort pulses are usually separated procedures. For few-cycle pulses with significant spatial inhomogeneities and poor beam quality, a fully spatio-temporal beam characterization is necessary. Here we report on a new concept for a joint two-dimensional mapping of local temporal coherence and local wavefront tilt based on the combination of collinear autocorrelation and Shack-Hartmann wavefront sensing. Essentially for this "wavefront autocorrelation" is a splitting of the beam into a matrix of Bessel-like sub-beams by an array of thin-film microaxicons. The sub-beams are further processed by a two-dimensional collinear autocorrelation setup. The second harmonic distribution of sub-beams at a defined distance is imaged onto a CCD camera. The nondiffractive sub-beams ensure an extended depth of focus and a low sensitivity towards angular misalignment or axial displacement. With low-dispersion small-angle refractive-reflective shapers, wavefront-sensing of Ti:sapphire laser wavepackets was demonstrated experimentally for the first time.

  20. Removing autocorrelation in spectral optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Ai, Jun; Wang, Lihong V.

    2006-02-01

    We have developed a new algorithm and configuration for removing the autocorrelation of the object wave in spectral optical coherence tomography. The self-interferogram of the object wave is acquired synchronously with the standard interferogram of the recombined object and reference waves. The former is then subtracted from the latter after Fourier transformation. The algorithm is validated by numerical simulation and by experimental measurement of a USAF target and a feline eye.

  1. Michelson-type all-reflective interferometric autocorrelation in the VUV regime

    NASA Astrophysics Data System (ADS)

    Gebert, T.; Rompotis, D.; Wieland, M.; Karimi, F.; Azima, A.; Drescher, M.

    2014-07-01

    We demonstrate second-order interferometric autocorrelation of a pulse in the vacuum-ultraviolet (VUV) spectral range using an optical arrangement equivalent to a Michelson interferometer. In an all-reflective design, wavefront splitting is realized with two moveable interdigitated reflective gratings forming a diffraction pattern with well separated orders and an intensity distribution depending on the precisely adjustable path-length difference. An imaging time-of-flight spectrometer is able to spatially select ions created by nonlinear two-photon absorption in the focus of the zeroth diffraction order. This arrangement is used to demonstrate interferometric autocorrelation in krypton with femtosecond VUV pulses at 160 nm wavelength. In addition to the pulse duration, which is already accessible with non-collinear intensity autocorrelation, the full interferometric contrast of the presented approach enables us to extract also information on temporal phases.

  2. The 1st of April 2470 BC Total Solar Eclipse Seen by the Prophet Ibraheem

    NASA Astrophysics Data System (ADS)

    Yousef, S. M.

    The Holy Quran describes a phenomenon seen by young Abraham that can only fit a solar eclipse. Two criteria were given for this particular eclipse; first only one planet was seen as soon as it got dark and second no corona was seen. In order to justify the first selection rule, examinations of solar and planetary longitudes for total solar eclipses passing over Babel were carried out. Only the eclipse of the 1st of April 2470 BC meets this condition, as it was only Venus that was seen at that eclipse. The second selection rule was also naturally fulfilled, as Babel happened to be on the border of the totality zone hence no corona was seen, however all the time the moon glistened as Baily's beads. There is no doubt that the prophet Abraham witnessed the 1st of April total solar eclipse that passed over Babel. This will put him about 470 years backward than it was previously anticipated.

  3. Idaho National Laboratory Quarterly Performance Analysis - 1st Quarter FY2015

    SciTech Connect

    Mitchell, Lisbeth A.

    2015-03-01

    This report is published quarterly by the Idaho National Laboratory (INL) Quality and Performance Management Organization. The Department of Energy (DOE) Occurrence Reporting and Processing System (ORPS), as prescribed in DOE Order 232.2, “Occurrence Reporting and Processing of Operations Information,” requires a quarterly analysis of events, both reportable and not reportable, for the previous 12 months. This report is the analysis of 73 reportable events (27 from the 1St Qtr FY-15 and 46 from the prior three reporting quarters), as well as 38 other issue reports (including nine not reportable events and Significant Category A and B conditions reported during the1st Qtr FY-15) identified at INL during the past 12 months.

  4. Lag-One Autocorrelation in Short Series: Estimation and Hypotheses Testing

    ERIC Educational Resources Information Center

    Solanas, Antonio; Manolov, Rumen; Sierra, Vicenta

    2010-01-01

    In the first part of the study, nine estimators of the first-order autoregressive parameter are reviewed and a new estimator is proposed. The relationships and discrepancies between the estimators are discussed in order to achieve a clear differentiation. In the second part of the study, the precision in the estimation of autocorrelation is…

  5. ["1st Therapeutic Red Cross Hospital" during the civil war].

    PubMed

    Simonenko, V B; Abashin, V G

    2014-04-01

    The article presents the documentary information about the founding, the establishment and early years of the 1st Therapeutic Red Cross Hospital - in the future - Mandryka Central Military Clinical Hospital of the Ministry of Defence of the Russian Federation. Presented the work of the Hospital during the dificult period of the Civil War, typhus epidemic, famine and devastation. Specified its staffing structure, command, medical and administrative staff, travel and accommodation till the moment of the deployment in the Silver Lane in Moscow.

  6. Complex singularities of the fluid velocity autocorrelation function

    NASA Astrophysics Data System (ADS)

    Chtchelkatchev, N. M.; Ryltsev, R. E.

    2015-11-01

    There are intensive debates regarding the nature of supercritical fluids: if their evolution from liquid-like to gas-like behavior is a continuous multistage process or there is a sharp well-defined crossover. Velocity auto-correlation function Z is the established detector of evolution of fluid particles dynamics. Usually, complex singularities of correlation functions give more information. For this reason, we investigate Z in complex plane of frequencies using numerical analytic continuation. We have found that naive picture with few isolated poles fails describing Z(ω) of one-component Lennard-Jones (LJ) fluid. Instead, we see the singularity manifold forming branch cuts extending approximately parallel to the real frequency axis. That suggests LJ velocity autocorrelation function is a multivalued function of complex frequency. The branch cuts are separated from the real axis by the well-defined "gap" whose width corresponds to an important time scale of a fluid characterizing crossover of system dynamics from kinetic to hydrodynamic regime. Our working hypothesis is that the branch cut origin is related to competition between one-particle dynamics and hydrodynamics. The observed analytic structure of Z is very stable under changes in the temperature; it survives at temperatures two orders of magnitude higher than the critical one.

  7. Spatial Autocorrelation Approaches to Testing Residuals from Least Squares Regression.

    PubMed

    Chen, Yanguang

    2016-01-01

    In geo-statistics, the Durbin-Watson test is frequently employed to detect the presence of residual serial correlation from least squares regression analyses. However, the Durbin-Watson statistic is only suitable for ordered time or spatial series. If the variables comprise cross-sectional data coming from spatial random sampling, the test will be ineffectual because the value of Durbin-Watson's statistic depends on the sequence of data points. This paper develops two new statistics for testing serial correlation of residuals from least squares regression based on spatial samples. By analogy with the new form of Moran's index, an autocorrelation coefficient is defined with a standardized residual vector and a normalized spatial weight matrix. Then by analogy with the Durbin-Watson statistic, two types of new serial correlation indices are constructed. As a case study, the two newly presented statistics are applied to a spatial sample of 29 China's regions. These results show that the new spatial autocorrelation models can be used to test the serial correlation of residuals from regression analysis. In practice, the new statistics can make up for the deficiencies of the Durbin-Watson test.

  8. [Granuloma Gravidarum in a 37-year-old 1st Gravida, 1st Para--A Case Report].

    PubMed

    Findeklee, S

    2015-10-01

    The granuloma gravidarum is a rare benign tumour with gingival origin. It occurs in circa 0.2% of pregnancies. Mostly we see an asymptomatic course of disease terminated by hormonal changes after delivery. If the granuloma is associated with complaints of the pregnant woman, for example masticational pain or recurrent bleedings, therapeutic options are conservative therapy, surgery or delivery. We report the case of a 37-year-old 1st gravida, 1st para who had an induced delivery in the 39+2 gestational week because of a symptomatic granuloma gravidarum. We saw a spontaneous remission of the granuloma within 3 months post partum. The case report underlines the importance of suitable information for pregnant women about oral hygiene and the necessity of regular dental controls during pregnancy for prophylaxis of granuloma gravidarum.

  9. Simple, picojoule-sensitive ultraviolet autocorrelator based on two-photon conductivity in sapphire.

    PubMed

    Leedle, Kenneth J; Urbanek, Karel E; Byer, Robert L

    2017-03-10

    We present a simple autocorrelator for ultraviolet pulses based on two-photon conductivity in a bench-top fabricatable sapphire sensor. We perform measurements on femtosecond 226-278 nm ultraviolet pulses from the third and fourth harmonics of a standard 76 MHz titanium sapphire oscillator and picosecond 266 nm pulses from the fourth harmonic of a 1064 nm 50 MHz neodymium vanadate oscillator. Our device is sensitive to 2.6 pJ ultraviolet pulses with peak powers below 20 W. These results represent the lowest measured autocorrelation peak powers by over one order of magnitude for a system with no reference pulse in the deep ultraviolet (<300  nm). The autocorrelator can potentially support UV pulse lengths from 50 fs-10s of picoseconds.

  10. Simple, picojoule-sensitive ultraviolet autocorrelator based on two-photon conductivity in sapphire

    NASA Astrophysics Data System (ADS)

    Leedle, Kenneth J.; Urbanek, Karel E.; Byer, Robert L.

    2017-03-01

    We present a simple autocorrelator for ultraviolet pulses based on two-photon conductivity in a bench-top fabricatable sapphire sensor. We perform measurements on femtosecond 226 - 278 nm ultraviolet pulses from the third and fourth harmonics of a standard 76 MHz titanium sapphire oscillator and picosecond 266 nm pulses from the fourth harmonic of a 1064 nm 50 MHz neodymium vanadate oscillator. Our device is sensitive to 2.6 pJ ultraviolet pulses with peak powers below 20 W. These results represent the lowest measured autocorrelation peak powers by over one order of magnitude for a system with no reference pulse in the deep ultraviolet ( < 300 nm). The autocorrelator can potentially support UV pulse lengths from 50 fs - 10's of picoseconds.

  11. Rapid scanning autocorrelator for measurements of picosecond laser pulses

    NASA Astrophysics Data System (ADS)

    Harde, H.; Burggraf, H.

    1981-08-01

    A rapid scanning autocorrelation interferometer for measurements of picosecond laser pulses is described which uses a rotating prism as scanning device in one arm of the interferometer to permit continuous display of autocorrelation traces at audio frequencies on an oscilloscope. Scan widths of more than 500 ps with high linearity can be achieved. Autocorrelation measurements of picosecond pulses from a synchronously pumped mode-locked dye laser are presented.

  12. The 1st All-Russian Workshop on Archaeoastronomy

    NASA Astrophysics Data System (ADS)

    Bochkarev, Nikolai G.

    2007-08-01

    The 1st All-Russia Workshop on Archaeoastronomy “Astronomical and World-Outlook Meaning of the Archaeological Monuments of South Ural” was held on June 19-25, 2006, at the ground of the archaeological center “Arkaim” (Chelyabinsk Region). Besides about 30 talks, astronomical measurements were performed at two archaeological objects under intensive study: Arkaim Site (Bronze Epoch, XVIII-XVI c. B.C.) and tumuli “with whiskers” complex Kondurovsky (V-VIII c. A.D.). The promising character of the megalithic complex on the Vera Island (Lake Turgoyak) was stated.

  13. A Preliminary to War: The 1st Aero Squadron and the Mexican Punitive Expedition of 1916

    DTIC Science & Technology

    2003-01-01

    ordered a reconnaissance along the Mexican Northwestern railroad south toward Cumbre Pass in the Sierra Madre mountains. Dodd and Foulois flew this...Casas Grandes and Galeana Valleys ranged between 6,000 and 7,000 feet, and that Cumbre Pass lay at about 9,000 feet. All of these altitudes were higher...of the Cumbre Pass tunnel, but could go no farther. For two hours, 25 The 1st Aero Squadron in Mexico; probably following a mission by Signal Corps No

  14. Adaptive non-collinear autocorrelation of few-cycle pulses with an angular tunable bi-mirror

    SciTech Connect

    Treffer, A. Bock, M.; König, S.; Grunwald, R.; Brunne, J.; Wallrabe, U.

    2016-02-01

    Adaptive autocorrelation with an angular tunable micro-electro-mechanical system is reported. A piezo-actuated Fresnel bi-mirror structure was applied to measure the second order autocorrelation of near-infrared few-cycle laser pulses in a non-collinear setup at tunable superposition angles. Because of enabling measurements with variable scaling and minimizing the influence of distortions by adaptive self-reconstruction, the approach extends the capability of autocorrelators. Flexible scaling and robustness against localized amplitude obscurations are demonstrated. The adaptive reconstruction of temporal frequency information by the Fourier analysis of autocorrelation data is shown. Experimental results and numerical simulations of the beam propagation and interference are compared for variable angles.

  15. Low power, CMOS digital autocorrelator spectrometer for spaceborne applications

    NASA Technical Reports Server (NTRS)

    Chandra, Kumar; Wilson, William J.

    1992-01-01

    A 128-channel digital autocorrelator spectrometer using four 32 channel low power CMOS correlator chips was built and tested. The CMOS correlator chip uses a 2-bit multiplication algorithm and a full-custom CMOS VLSI design to achieve low DC power consumption. The digital autocorrelator spectrometer has a 20 MHz band width, and the total DC power requirement is 6 Watts.

  16. Seismic Body-Wave Interferometry Using Noise Auto-correlations for Crustal Structure

    NASA Astrophysics Data System (ADS)

    Oren, Can; Nowack, Robert L.

    2016-10-01

    In this study, we use ambient seismic noise recorded at selected broadband USArray Earthscope Transportable Array (TA) stations to obtain effective reflection seismograms using noise auto-correlations. In order to best retrieve the body-wave component of the Green's function beneath a station from ambient seismic noise, a number of processing steps are used, including temporal sign-bit normalization, spectral whitening, and band-pass filtering. Hourly auto-correlations are stacked for different time periods including one day, one month, and one year. On the final stack, different amplitude gain functions are applied, including automatic gain control (AGC), to equalize the correlation amplitudes. The robustness of the resulting ambient noise auto-correlations is first tested on a TA station in Nevada where we are able to identify arrivals similar to those found in an earlier study. We then investigated noise auto-correlations applied to several USArray TA stations in the central U.S., and the results were then compared with reflectivity synthetics for an average crustal model based on CRUST 1.0 where an AGC was used to enhance the later arrivals. Different stacking periods are also investigated in order to find stable correlation stacks.

  17. Seismic body-wave interferometry using noise autocorrelations for crustal structure

    NASA Astrophysics Data System (ADS)

    Oren, Can; Nowack, Robert L.

    2017-01-01

    In this study, we use ambient seismic noise recorded at selected broad-band USArray Earthscope Transportable Array (TA) stations to obtain effective reflection seismograms using noise autocorrelations. In order to best retrieve the body-wave component of the Green's function beneath a station from ambient seismic noise, a number of processing steps are used, including temporal sign-bit normalization, spectral whitening and bandpass filtering. Hourly autocorrelations are stacked for different time periods including one day, one month and one year. On the final stack, different amplitude gain functions are applied, including automatic gain control (AGC), to equalize the correlation amplitudes. The robustness of the resulting ambient noise autocorrelations is first tested on a TA station in Nevada where we are able to identify arrivals similar to those found in an earlier study. We then investigated noise autocorrelations applied to several USArray TA stations in the central U.S., and the results were then compared with reflectivity synthetics for an average crustal model based on CRUST 1.0 where an AGC was used to enhance the later arrivals. Different stacking periods are also investigated in order to find stable correlation stacks.

  18. A simplified common-path autocorrelator based on Fizeau interferometer

    NASA Astrophysics Data System (ADS)

    Yuan, Yonggui; Yang, Jun; Zhou, Ai; Yuan, Libo

    2011-05-01

    We propose a simplified common-path autocorrelator based on Fizeau interferometer for quasi-distributed measurement. A four-port fiber circulator is employed to connect broadband light source, fiber sensor array, Fizeau interferometer and photodetector, constructing a most simple configuration and common-path between sensing and reference signals. This common-path configuration of the autocorrelator can greatly reduce the polarization and dispersion mismatch between sensing and reference signals. The use of circulator can also avoid reflective light from sensor array reentering into light source, which can improve the stability and efficiency of the autocorrelator. The optimization of the autocorrelator is theoretically discussed, and a seven-sensor autocorrelator is experimentally demonstrated. The common-path sensing system is quite suitable for quasi-distributed measurement of strain and temperature in smart structures.

  19. 1st Workshop of the Canadian Society for Virology

    PubMed Central

    McCormick, Craig; Grandvaux, Nathalie

    2017-01-01

    The 1st Workshop of the Canadian Society for Virology (CSV2016) was a Special Workshop of the 35th Annual Meeting for the American Society for Virology, held on 18 June 2016 on the beautiful Virginia Tech campus in Blacksburg, Virginia. The workshop provided a forum for discussion of recent advances in the field, in an informal setting conducive to interaction with colleagues. CSV2016 featured two internationally-renowned Canadian keynote speakers who discussed translational virology research; American Society for Virology President Grant McFadden (then from University of Florida, now relocated to Arizona State University) who presented his studies of oncolytic poxviruses, while Matthew Miller (McMaster University) reviewed the prospects for a universal influenza vaccine. The workshop also featured a variety of trainee oral and poster presentations, and a panel discussion on the topic of the future of the CSV and virus research in Canada. PMID:28335511

  20. An autocorrelation model of bat sonar.

    PubMed

    Wiegrebe, Lutz

    2008-06-01

    Their sonar system allows echolocating bats to navigate with high skill through a complex, three- dimensional environment at high speed and low light. The auditory analysis of the echoes of their ultrasonic sounds requires a detailed comparison of the emission and echoes. Here an auditory model of bat sonar is introduced and evaluated against a set of psychophysical phantom-target, echo-acoustic experiments. The model consists of a relatively detailed simulation of auditory peripheral processing in the bat, Phyllostomus discolor, followed by a functional module consisting of a strobed, normalised, autocorrelation in each frequency channel. The model output is accumulated in a sonar image buffer. The model evaluation is based on the comparison of the image-buffer contents generated in individually simulated psychophysical trials. The model provides reasonably good predictions for both temporal and spectral behavioural sonar processing in terms of sonar delay-, roughness, and phase sensitivity and in terms of sensitivity to the temporal separations in two-front targets and the classification of spectrally divergent phantom targets.

  1. MEASUREMENTS OF STELLAR MAGNETIC FIELDS USING AUTOCORRELATION OF SPECTRA

    SciTech Connect

    Borra, E. F.; Deschatelets, D.

    2015-11-15

    We present a novel technique that uses the autocorrelation of the spectrum of a star to measure the line broadening caused by the modulus of its average surface magnetic field. The advantage of the autocorrelation comes from the fact that it can detect very small spectral line broadening effects because it averages over many spectral lines and therefore gives an average with a very high signal-to-noise ratio. We validate the technique with the spectra of known magnetic stars and obtain autocorrelation curves that are in full agreement with published magnetic curves obtained with Zeeman splitting. The autocorrelation also gives less noisy curves so that it can be used to obtain very accurate curves. We degrade the resolution of the spectra of these magnetic stars to lower spectral resolutions where the Zeeman splitting is undetectable. At these resolutions, the autocorrelation still gives good quality curves, thereby showing that it can be used to measure magnetic fields in spectra where the Zeeman splitting is significantly smaller than the width of the spectral line. This would therefore allow observing magnetic fields in very faint Ap stars with low-resolution spectrographs, thereby greatly increasing the number of known magnetic stars. It also demonstrates that the autocorrelation can measure magnetic fields in rapidly rotating stars as well as weak magnetic fields that give a Zeeman splitting smaller than the intrinsic width of the spectral lines. Finally, it shows that the autocorrelation can be used to find unknown magnetic stars in low-resolution spectroscopic surveys.

  2. T1/ST2 promotes T helper 2 cell activation and polyfunctionality in bronchopulmonary mycosis.

    PubMed

    Piehler, D; Grahnert, A; Eschke, M; Richter, T; Köhler, G; Stenzel, W; Alber, G

    2013-03-01

    Interleukin (IL)-33 enhances T helper (Th)2 immunity via its receptor T1/ST2. Infection with the yeast-like pathogen Cryptococcus neoformans is usually controlled by a Th1-mediated immune response. The mechanisms responsible for nonprotective Th2 immunity leading to allergic inflammation in pulmonary cryptococcosis are still not fully understood. Using a murine pulmonary model of C. neoformans infection, we report that T1/ST2 expression correlates with the intensity of Th2 activation, as demonstrated by the expression of CD25 and CD44 and downregulation of CD62L. Antigen-specific T1/ST2(+) Th cells are the primary source of the Th2 cytokines IL-5 and IL-13 as compared with wild-type T1/ST2(-) Th cells or Th cells from T1/ST2(-/-) mice. In addition, T1/ST2(+) Th cells almost exclusively contain bi- and trifunctional Th2 cytokine-producing Th cells compared with T1/ST2(-) Th cells or Th cells from T1/ST2(-/-) mice. Finally, T1/ST2-driven Th2 development resulted in defective pulmonary fungal control. These data demonstrate that T1/ST2 directs Th2 cell activation and polyfunctionality in allergic bronchopulmonary mycosis.

  3. 1st Advanced Marine Renewable Energy Instrumentation Experts Workshop

    SciTech Connect

    none,

    2011-10-01

    The U.S. marine energy industry is actively pursuing development of offshore wind and marine hydrokinetic (MHK) energy systems. Experience in the wind energy sector demonstrates that new technology development requires thorough measurement and characterization of the environmental conditions prevalent at installation sites and of technology operating in the field. Presently, there are no turn-key instrumentation system solutions that meet the measurement needs of the marine energy industry. The 1st Advanced Marine Renewable Energy Instrumentation Experts Workshop brought together technical experts from government laboratories, academia, and industry representatives from marine energy, wind, offshore oil and gas, and instrumentation developers to present and discuss the instrumentation needs of the marine energy industry. The goals of the meeting were to: 1. Share the latest relevant knowledge among technical experts; 2. Review relevant state-of-the-art field measurement technologies and methods; 3. Review lessons learned from recent field deployments; 4. Identify synergies across different industries; 5. Identify gaps between existing and needed instrumentation capabilities; 6. Understand who are the leading experts; 7. Provide a forum where stakeholders from the marine energy industry could provide substantive input in the development of new marine energy field deployable instrumentation packages.

  4. Time evolution of the autocorrelation function in dynamical replica theory

    NASA Astrophysics Data System (ADS)

    Sakata, A.

    2013-04-01

    Asynchronous dynamics given by the master equation in the Sherrington-Kirkpatrick (SK) spin-glass model is studied based on dynamical replica theory (DRT) with an extension to take into account the autocorrelation function. The dynamical behaviour of the system is approximately described by dynamical equations of the macroscopic quantities: magnetization, energy contributed by randomness and the autocorrelation function. The dynamical equations under the replica symmetry assumption are derived by introducing the subshell equipartitioning assumption and exploiting the replica method. The obtained dynamical equations are compared with Monte Carlo simulations, and it is demonstrated that the proposed formula describes well the time evolution of the autocorrelation function in some parameter regions. The study offers a reasonable description of the autocorrelation function in the SK spin-glass system.

  5. Two-valued sequences with perfect periodic autocorrelation

    NASA Astrophysics Data System (ADS)

    Golomb, Solomon W.

    1992-04-01

    A signal with out-of-phase autocorrelation identically equal to zero is very valuable for CW radars, since there will be no range sidelobes. This paper describes three different ways in which this ideal situation can be achieved, each one using a periodic two-value sequence as the signal. The methodology exploits a mathematical equivalence between two-valued sequences with two-level periodic autocorrelation and certain combinatorial objects called cyclic difference sets.

  6. Mode Analysis with Autocorrelation Method (Single Time Series) in Tokamak

    NASA Astrophysics Data System (ADS)

    Saadat, Shervin; Salem, Mohammad K.; Goranneviss, Mahmoud; Khorshid, Pejman

    2010-08-01

    In this paper plasma mode analyzed with statistical method that designated Autocorrelation function. Auto correlation function used from one time series, so for this purpose we need one Minov coil. After autocorrelation analysis on mirnov coil data, spectral density diagram is plotted. Spectral density diagram from symmetries and trends can analyzed plasma mode. RHF fields effects with this method ate investigated in IR-T1 tokamak and results corresponded with multichannel methods such as SVD and FFT.

  7. A Method for Detecting Positive Growth Autocorrelation without Marking Individuals

    PubMed Central

    Brooks, Mollie E.; McCoy, Michael W.; Bolker, Benjamin M.

    2013-01-01

    In most ecological studies, within-group variation is a nuisance that obscures patterns of interest and reduces statistical power. However, patterns of within-group variability often contain information about ecological processes. In particular, such patterns can be used to detect positive growth autocorrelation (consistent variation in growth rates among individuals in a cohort across time), even in samples of unmarked individuals. Previous methods for detecting autocorrelated growth required data from marked individuals. We propose a method that requires only estimates of within-cohort variance through time, using maximum likelihood methods to obtain point estimates and confidence intervals of the correlation parameter. We test our method on simulated data sets and determine the loss in statistical power due to the inability to identify individuals. We show how to accommodate nonlinear growth trajectories and test the effects of size-dependent mortality on our method's accuracy. The method can detect significant growth autocorrelation at moderate levels of autocorrelation with moderate-sized cohorts (for example, statistical power of 80% to detect growth autocorrelation ρ2 = 0.5 in a cohort of 100 individuals measured on 16 occasions). We present a case study of growth in the red-eyed tree frog. Better quantification of the processes driving size variation will help ecologists improve predictions of population dynamics. This work will help researchers to detect growth autocorrelation in cases where marking is logistically infeasible or causes unacceptable decreases in the fitness of marked individuals. PMID:24204620

  8. Use of autocorrelation of wavelet coefficients for fault diagnosis

    NASA Astrophysics Data System (ADS)

    Rafiee, J.; Tse, P. W.

    2009-07-01

    This paper presents a novel time-frequency-based feature recognition system for gear fault diagnosis using autocorrelation of continuous wavelet coefficients (CWC). Furthermore, it introduces an original mathematical approximation of gearbox vibration signals which approximates sinusoidal components of noisy vibration signals generated from gearboxes, including incipient and serious gear failures using autocorrelation of CWC. First, the drawbacks of the continuous wavelet transform (CWT) have been eliminated using autocorrelation function. Secondly, the autocorrelation of CWC is introduced as an original pattern for fault identification in machine condition monitoring. Thirdly, a sinusoidal summation function consisting of eight terms was used to approximate the periodic waveforms generated by autocorrelation of CWC for normal gearboxes (NGs) as well as occurrences of incipient and severe gear fault (e.g. slight-worn, medium-worn, and broken-tooth gears). In other words, the size of vibration signals can be reduced with minimal loss of significant frequency content by means of the sinusoidal approximation of generated autocorrelation waveforms of CWC as reported in this paper.

  9. Autocorrelation of laser pulses by optical processing of Fabry-Perot spectrograms.

    PubMed

    Colombeau, B; Froehly, C; Vampouille, M

    1980-02-15

    This paper describes the principles and experimental implementation of a new optical technique based on Fourier analysis for second-order statistics of short coherent light pulses. Using only passive filtering operations, we obtained images of the autocorrelation functions of the optical fields of light pulses, derived from ode-locked Nd:YAG laser pulses, with 40-psec to 4-nsec duration. An application of the method to a shaped sequence of 40-psec pulses is reported.

  10. Performance of signal-to-noise ratio estimation for scanning electron microscope using autocorrelation Levinson-Durbin recursion model.

    PubMed

    Sim, K S; Lim, M S; Yeap, Z X

    2016-07-01

    A new technique to quantify signal-to-noise ratio (SNR) value of the scanning electron microscope (SEM) images is proposed. This technique is known as autocorrelation Levinson-Durbin recursion (ACLDR) model. To test the performance of this technique, the SEM image is corrupted with noise. The autocorrelation function of the original image and the noisy image are formed. The signal spectrum based on the autocorrelation function of image is formed. ACLDR is then used as an SNR estimator to quantify the signal spectrum of noisy image. The SNR values of the original image and the quantified image are calculated. The ACLDR is then compared with the three existing techniques, which are nearest neighbourhood, first-order linear interpolation and nearest neighbourhood combined with first-order linear interpolation. It is shown that ACLDR model is able to achieve higher accuracy in SNR estimation.

  11. 94. DETAIL, SAME BEAN AS ABOVE, MARKED 'PATENTED DEC. 1ST ...

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

    94. DETAIL, SAME BEAN AS ABOVE, MARKED 'PATENTED DEC. 1ST 1857' - Smithsonian Institution Building, 1000 Jefferson Drive, between Ninth & Twelfth Streets, Southwest, Washington, District of Columbia, DC

  12. VIEW WEST, 1ST FLOOR, EAST ROOM, HYDRAULIC COTTON PRESS, DETAIL, ...

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

    VIEW WEST, 1ST FLOOR, EAST ROOM, HYDRAULIC COTTON PRESS, DETAIL, CONTINENTAL GIN COMPANY HYDRAULIC TANK - Magnolia Plantation, Cotton Gins & Presses, LA Route 119, Natchitoches, Natchitoches Parish, LA

  13. Idaho National Laboratory Quarterly Occurrence Analysis - 1st Quarter FY 2016

    SciTech Connect

    Mitchell, Lisbeth Ann

    2016-03-01

    This report is published quarterly by the Idaho National Laboratory (INL) Quality and Performance Management Organization. The Department of Energy (DOE) Occurrence Reporting and Processing System (ORPS), as prescribed in DOE Order 232.2, “Occurrence Reporting and Processing of Operations Information,” requires a quarterly analysis of events, both reportable and not reportable, for the previous 12 months. This report is the analysis of 74 reportable events (16 from the 1st Qtr FY-16 and 58 from the prior three reporting quarters), as well as 35 other issue reports (including events found to be not reportable and Significant Category A and B conditions) identified at INL during the past 12 months (15 from this quarter and 20 from the prior three quarters).

  14. Retrieval of the P wave reflectivity response from autocorrelation of seismic noise: Jakarta Basin, Indonesia

    NASA Astrophysics Data System (ADS)

    Saygin, Erdinc; Cummins, Phil R.; Lumley, David

    2017-01-01

    We autocorrelate the continuously recorded seismic wavefield across a dense network of seismometers to map the P wave reflectivity response of the Jakarta Basin, Indonesia. The proximity of this mega city to known active faults and the subduction of the Australian plate, especially when the predominance of masonry construction and thick sedimentary basin fill are considered, suggests that it is a hot spot for seismic risk. In order to understand the type of ground motion that earthquakes might cause in the basin, it is essential to obtain reliable information on its seismic velocity structure. The body wave reflections are sensitive to the sharp velocity contrasts, which makes them useful in seismic imaging. Results show autocorrelograms at different seismic stations with reflected-wave travel time variations, which reflect the variation in basement depth across the thick sedimentary basin. We also confirm the validity of the observed autocorrelation waveforms by conducting a 2-D full waveform modeling.

  15. Evaluation of estimation, prediction and inference for autocorrelated latent variable modeling of binary data-a simulation study.

    PubMed

    Hutmacher, Matthew M

    2016-06-01

    Longitudinal models of binary or ordered categorical data are often evaluated for adequacy by the ability of these to characterize the transition frequency and type between response states. Drug development decisions are often concerned with accurate prediction and inference of the probability of response by time and dose. A question arises on whether the transition probabilities need to be characterized adequately to ensure accurate response prediction probabilities unconditional on the previous response state. To address this, a simulation study was conducted to assess bias in estimation, prediction and inferences of autocorrelated latent variable models (ALVMs) when the transition probabilities are misspecified due to ill-posed random effects structures, inadequate likelihood approximation or omission of the autocorrelation component. The results may be surprising in that these suggest that characterizing autocorrelation in ALVMs is not as important as specifying a suitably rich random effects structure.

  16. Investigations of Passive Seismic Body-Wave Interferometry Using Noise Auto-correlations for Crustal and Upper Mantle Structure

    NASA Astrophysics Data System (ADS)

    Oren, C.; Nowack, R. L.

    2015-12-01

    It is known that the positive lags of the auto-correlation for the seismic transmission response of a layered medium correspond to the reflection seismogram (Claerbout, 1968). In this study, we investigate the use of ambient seismic noise recorded at selected broadband USArray EarthScope Transportable Array (TA) stations to obtain effective reflection seismograms for frequencies up to 1 Hz. The goal is to determine the most suitable parameters used for the processing of ambient seismic noise for the identification of crustal and upper mantle reflections and to minimize unwanted artifacts in the noise correlations. In order to best retrieve the body-wave components of the Green's function beneath a station, a number of processing steps are required. We first remove the instrument response and apply a temporal normalization to remove the effects of the most energetic sources. Next we implement spectral whitening. We test several operators for the spectral whitening where the undulations of the power spectrum are related to the strengths of later arrivals in the auto-correlation. Different filters are then applied to the auto-correlation functions, including Gaussian and zero phase Butterworth filters, in order to reduce the effect of side lobes. Hourly auto-correlations are then stacked for up to one year. On the final stack, Automatic Gain Control (AGC) is applied to equalize the correlation amplitudes in the time domain. The robustness of the resulting ambient noise auto-correlation is first tested on selected TA stations in Nevada, where we are able to identify PmP and SmS arrivals similar to those found by Tibuleac and von Seggern (2012). We then investigate noise auto-correlations applied to selected USArray TA stations in the central US.

  17. The impact of temporal auto-correlation mismatch on the assimilation of satellite-derived surface soil moisture retrievals

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Satellite-based surface soil moisture retrievals are commonly assimilated into eco-hydrological models in order to obtain improved profile soil moisture estimates. However, differences in temporal auto-correlation structure between these retrievals and comparable model-based predictions can potentia...

  18. The resemblance of an autocorrelation function to a power spectrum density for a spike train of an auditory model

    NASA Astrophysics Data System (ADS)

    Ushakov, Y. V.; Dubkov, A. A.; Spagnolo, B.

    2013-01-01

    In this work we develop an analytical approach for calculation of the all-order interspike interval density (AOISID), show its connection with the autocorrelation function, and try to explain the discovered resemblance of AOISID to the power spectrum of the same spike train.

  19. Autocorrelation of location estimates and the analysis of radiotracking data

    USGS Publications Warehouse

    Otis, D.L.; White, Gary C.

    1999-01-01

    The wildlife literature has been contradictory about the importance of autocorrelation in radiotracking data used for home range estimation and hypothesis tests of habitat selection. By definition, the concept of a home range involves autocorrelated movements, but estimates or hypothesis tests based on sampling designs that predefine a time frame of interest, and that generate representative samples of an animal's movement during this time frame, should not be affected by length of the sampling interval and autocorrelation. Intensive sampling of the individual's home range and habitat use during the time frame of the study leads to improved estimates for the individual, but use of location estimates as the sample unit to compare across animals is pseudoreplication. We therefore recommend against use of habitat selection analysis techniques that use locations instead of individuals as the sample unit. We offer a general outline for sampling designs for radiotracking studies.

  20. U.S. Army Chemical Corps Historical Studies, Gas Warfare in World War I: The 1st Division in the Meuse-Argonne 1-12 October 1918

    DTIC Science & Technology

    1957-08-01

    October, instead of 30 September-I October 0 On the night of the relief the .Jnemy began shelling at 10s00 porn October 1st and continued until 4s00... Juvin and Landre, out off the Argoure front, and attack in rear of the Brunhild position to effect decisive action on the Group -Argonnej." 8 7 At...attack, fired on the Son’.erance area and north of St Georges et Landres, Juvin , Marcq, and Champigxeulle. 93 Company C, 1st Gas Regiment, was ordered

  1. Autocorrelation and variability of indoor air quality measurements.

    PubMed

    Luoma, M; Batterman, S A

    2000-01-01

    Measurements of gaseous and particulate concentrations are used to characterize the indoor environment, but such measurements may reflect temporary conditions that are not representative of longer time periods. Moreover, indoor air quality (IAQ) measurements are autocorrelated, a result of limited mixing and air exchange, cyclic emissions, HVAC operation, and other factors. This article analyzes the autocorrelation and variability of IAQ measurements using time series analysis techniques in conjunction with a simple IAQ model. Autocorrelations may be estimated using the air exchange rate (alpha) and ventilation effectiveness (epsilon) of the building or room under study, or estimated from pollutant measurements. From this, the variability, required sample size, and other sampling parameters are estimated. The method is tested in a case study in which particle number, fungi, bacteria, and carbon dioxide concentrations were continuously measured in an office building over a 1-week period. The estimated air exchange rate (1.4/hr) for area studied was predicted to yield autocorrelation coefficients of approximately 0.5 for measurements collected on 30-min intervals. Autocorrelation coefficients based on airborne measurements (lag 0.5 hr) ranged from 0.5 to 0.7 for 1-25 microm diameter particles, fungi, and CO2, but near zero for particles < or =1 microm diameter and bacteria. As expected, the variability of measurements with the lowest autocorrelation decreased the most at long sampling times. The implications for spaces with low alpha * epsilon products are that measurements may not benefit significantly from longer averaging periods, measurements on any single day may not be representative, and day-to-day variability may be significant. Steps to determine sample sizes, averaging times, and sampling strategies that can improve the representativeness of IAQ measurements are discussed.

  2. Variance of size-age curves: Bootstrapping with autocorrelation

    USGS Publications Warehouse

    Bullock, S.H.; Turner, R.M.; Hastings, J.R.; Escoto-Rodriguez, M.; Lopez, Z.R.A.; Rodrigues-Navarro, J. L.

    2004-01-01

    We modify a method of estimating size-age relations from a minimal set of individual increment data, recognizing that growth depends not only on size but also varies greatly among individuals and is consistent within an individual for several to many time intervals. The method is exemplified with data from a long-lived desert plant and a range of autocorrelation factors encompassing field-measured values. The results suggest that age estimates based on size and growth rates with only moderate autocorrelation are subject to large variation, which raises major problems for prediction or hindcasting for ecological analysis or management.

  3. Allied Forces. 1st Airborne Task Force. Field Order Number 1

    DTIC Science & Technology

    1944-08-05

    any organization of the ground in the TRANS—EN—PROVENCE- LES ARCS—ROQUEBRUNE-- MARCHANDISE —LA VAUGINE area inclusive. £_. Observe for movement of...by telephone, or courier as folio (1) Strength (2) Killed, captured, missing ;.;.nd interned (3) Hospitalized ’ (4.) Returned to duty and...Definitions: (1) Effective strength Is the present for duty strength at the tiiR« thfe report is compiled, (2) Killed, captured, missing and interned

  4. Thermophoresis and Wind Lifting Particles on Mars: 1st Order Approximation

    NASA Astrophysics Data System (ADS)

    Buzan, J. R.

    2009-12-01

    Dust devils on Mars have been attributed to the haze in the Martian atmosphere (Balme and Greeley 2006). Numerical simulations of vortices have limited the number of vortices recorded by Viking that could entrain dust particles due to high threshold wind velocity (Ryan and Lucich 1983). Thermophoresis is a process of a momentum transfer from gas to dust particles through changes in the temperature gradient and has been proposed as a contributor to dust lifting on Mars (Wurm and Krauss 2006, Wurm et al 2008). Using IDL, a solid state greenhouse and photophoretic force laser model, similar to Wurm and Krauss 2006, was created. Data from Wurm et al 2008 and Greeley et al 1980 was applied to the model through a series of balancing force equations. The model quantified a new lower limit of velocities for entraining various particle diameters by a change of 44%. These estimates warrant further investigation into using thermophoresis with Mars wind tunnel experimentation. Threshold wind velocities for entrainment before (squares) and after (diamonds) application of Thermophoretic force on variety of particle sizes. Wind velocities before (stars) and after (triangles) application of Thermophoretic force on variety of particles sizes extrapolated to 1.6 m off the surface on Mars (height of Viking sensors).

  5. Velocity Autocorrelation Functions and Diffusion of Dusty Plasma

    SciTech Connect

    Ramazanov, T. S.; Dzhumagulova, K. N.; Daniyarov, T. T.; Dosbolayev, M. K.; Jumabekov, A. N.

    2008-09-07

    The velocity autocorrelation functions and square displacements were calculated on the basis of experimental data obtained on experimental setup with dc discharge. Computer simulation of the system of dust particles by the method of the Langevin dynamics was performed. The comparisons of experimental and theoretical results are given.

  6. Autocorrelation and Dominance Ratio in Monte Carlo Criticality Calculations

    SciTech Connect

    Ueki, Taro; Brown, Forrest B.; Parsons, D. Kent; Kornreich, Drew E.

    2003-11-15

    The cycle-to-cycle correlation (autocorrelation) in Monte Carlo criticality calculations is analyzed concerning the dominance ratio of fission kernels. The mathematical analysis focuses on how the eigenfunctions of a fission kernel decay if operated on by the cycle-to-cycle error propagation operator of the Monte Carlo stationary source distribution. The analytical results obtained can be summarized as follows: When the dominance ratio of a fission kernel is close to unity, autocorrelation of the k-effective tallies is weak and may be negligible, while the autocorrelation of the source distribution is strong and decays slowly. The practical implication is that when one analyzes a critical reactor with a large dominance ratio by Monte Carlo methods, the confidence interval estimation of the fission rate and other quantities at individual locations must account for the strong autocorrelation. Numerical results are presented for sample problems with a dominance ratio of 0.85-0.99, where Shannon and relative entropies are utilized to exclude the influence of initial nonstationarity.

  7. PROPAGATION AND EVOLUTION OF THE JUNE 1st 2008 CME IN THE INTERPLANETARY MEDIUM

    NASA Astrophysics Data System (ADS)

    Nieves-Chinchilla, T.; Lamb, D. A.; Davila, J. M.; Vinas, A. F.; Moestl, C.; Hidalgo, M. A.; Farrugia, C. J.; Malandraki, O.; Dresing, N.; Gómez-Herrero, R.

    2009-12-01

    In this work we present a study of the coronal mass ejection (CME) of June 1st of 2008 in the interplanetary medium. This event has been extensively studied by others because of its favorable geometry and the possible consequences of its peculiar initiation for space weather forecasting. We show an analysis of the evolution of the CME in the interplanetary medium in order to shed some light on the propagation mechanism of the ICME. We have determined the typical shock associated characteristics of the ICME in order to understand the propagation properties. Using two different non force-free models of the magnetic cloud allows us to incorporate expansion of the cloud. We use in-situ measurements from STEREO B/IMPACT to characterize the ICME. In addition, we use images from STEREO A/SECCHI-HI to analyze the propagation and visual evolution of the associated flux rope in the interplanetary medium. We compare and contrast these observations with the results of the analytical models.

  8. 28. ENGINE CLUSTER OF 1ST STAGE OF A SATURN I ...

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

    28. ENGINE CLUSTER OF 1ST STAGE OF A SATURN I ROCKET ENGINE LOCATED ON NORTH SIDE OF STATIC TEST STAND. - Marshall Space Flight Center, Saturn Propulsion & Structural Test Facility, East Test Area, Huntsville, Madison County, AL

  9. 4. VIEW WEST, WEST SIDE, SHOWING CHANNELS 1ST AND 2ND ...

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

    4. VIEW WEST, WEST SIDE, SHOWING CHANNELS 1ST AND 2ND VERTICAL BRACED DOUBLE ANGLES, DIAGONAL BRACING AND CROSS BRACED RAILING - Thirty-Sixth Street Bridge, Spanning Rabbit River, Hamilton, Allegan County, MI

  10. Introduction to the 1st International Symposium on Phytochemicals in Medicine and Food (ISPMF 2015).

    PubMed

    Zheng, Yafeng; Jassbi, Amir Reza; Xiao, Jianbo

    2016-03-30

    The 1st International Symposium on Phytochemicals in Medicine and Food (ISPMF 2015) was held in Shanghai, China, from June 26th to 29th, 2015. The 1st ISPMF was organized by the Phytochemical Society of Europe (PSE) and the Phytochemical Society of Asia (PSA). More than 270 scientists from 48 countries attended this meeting. The program of ISPMF 2015 consisted of 12 plenary lectures, 20 invited talks, and 55 short oral presentations in 16 sessions, including phytochemistry, phytomedicine, pharmacology, and application of phytochemicals in medicine and food. The 1st ISPMF has obtained support from Critical Reviews in Food Science and Nutrition, Food Chemistry, Phytochemistry Reviews, and Nutrients. As supported by Prof. Thomas F. Hofmann, a special issue on Journal of Agricultural and Food Chemistry (ACS) for the 1st ISPMF was initiated in January 2015.

  11. 45. MISSISSIPPI, LOWNDES CO. COLUMBUS RAILROAD BRIDGE End of 1st ...

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

    45. MISSISSIPPI, LOWNDES CO. COLUMBUS RAILROAD BRIDGE End of 1st St. S., Columbus, Ms. Turn span from SE. Sarcone Photography, Columbus, Ms. Sep 1978. - Bridges of the Upper Tombigbee River Valley, Columbus, Lowndes County, MS

  12. 46. MISSISSIPPI, LOWNDES CO. COLUMBUS RAILROAD BRIDGE End of 1st ...

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

    46. MISSISSIPPI, LOWNDES CO. COLUMBUS RAILROAD BRIDGE End of 1st St. S., Columbus, Ms. Overall view, from S. Sarcone Photography, Columbus, Ms. Sep 1978. - Bridges of the Upper Tombigbee River Valley, Columbus, Lowndes County, MS

  13. BLOEDNER MONUMENT (32ND INDIANA, 1ST GERMAN MONUMENT), SECTION C, FRONT ...

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

    BLOEDNER MONUMENT (32ND INDIANA, 1ST GERMAN MONUMENT), SECTION C, FRONT ELEVATION DETAIL OF GERMAN TEXT. VIEW TO NORTHEAST. - Cave Hill National Cemetery, 701 Baxter Avenue, Louisville, Jefferson County, KY

  14. 62. Neg. No. F75A, Jun 18, 1930, INTERIORWAREHOUSE, 1ST FLOOR, ...

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

    62. Neg. No. F-75A, Jun 18, 1930, INTERIOR-WAREHOUSE, 1ST FLOOR, STORAGE OF AUTOMOBILE COMPONENTS - Ford Motor Company Long Beach Assembly Plant, Assembly Building, 700 Henry Ford Avenue, Long Beach, Los Angeles County, CA

  15. VIEW SOUTH/SOUTHEAST LOOKING DOWN ON 2ND AQUEDUCT AND 1ST AQUEDUCT ...

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

    VIEW SOUTH/SOUTHEAST LOOKING DOWN ON 2ND AQUEDUCT AND 1ST AQUEDUCT CASCADES TOWARDS FILTRATION PLANT AND LOS ANGELES RESERVOIR - Los Angeles Aqueduct, Cascades Structures, Los Angeles, Los Angeles County, CA

  16. FDA Approves 1st Direct-to-Consumer Genetic Risk Tests

    MedlinePlus

    ... 164507.html FDA Approves 1st Direct-to-Consumer Genetic Risk Tests They screen for gene variants linked ... on Thursday approved the first direct-to-consumer genetic health risk tests. Known as the 23andMe Personal ...

  17. Noise autocorrelation spectroscopy with coherent Raman scattering

    NASA Astrophysics Data System (ADS)

    Xu, Xiaoji G.; Konorov, Stanislav O.; Hepburn, John W.; Milner, Valery

    2008-02-01

    Coherent anti-Stokes Raman scattering (CARS) with femtosecond laser pulses has become a widespread method in nonlinear optical spectroscopy and microscopy. As a third-order nonlinear process, femtosecond CARS exhibits high efficiency at low average laser power. High sensitivity to molecular structure enables detection of small quantities of complex molecules and non-invasive biological imaging. Temporal and spectral resolution of CARS is typically limited by the duration of the excitation pulses and their frequency bandwidth, respectively. Broadband femtosecond pulses are advantageous for time-resolved CARS spectroscopy, but offer poor spectral resolution. The latter can be improved by invoking optical or quantum interference at the expense of increasing complexity of instrumentation and susceptibility to noise. Here, we present a new approach to coherent Raman spectroscopy in which high resolution is achieved by means of deliberately introduced noise. The proposed method combines the efficiency of a coherent process with the robustness of incoherent light. It does require averaging over different noise realizations, but no temporal scanning or spectral pulse shaping as commonly used by frequency-resolved spectroscopic methods with ultrashort pulses.

  18. Exact exponent λ of the autocorrelation function for a soluble model of coarsening

    NASA Astrophysics Data System (ADS)

    Bray, A. J.; Derrida, B.

    1995-03-01

    The exponent λ that describes the decay of the autocorrelation function A(t) in a phase ordering system, A(t)~L-(d-λ), where d is the dimension and L the characteristic length scale at time t, is calculated exactly for the time-dependent Ginzburg-Landau equation in d=1. We find λ=0.3993835.... We also show explicitly that a small bias of positive domains over negative gives a magnetization which grows in time as M(t)~Lμ and prove that for the one-dimensional Ginzburg-Landau equation, μ=λ, exemplifying a general result.

  19. INL FY2014 1st Quarterly Performance Analysis

    SciTech Connect

    Kinghorn, Loran

    2014-07-01

    This report is published quarterly by the Idaho National Laboratory (INL) Performance Assurance Organization. The Department of Energy Occurrence Reporting and Processing System (ORPS), as prescribed in DOE Order 232.2 “Occurrence Reporting and Processing of Operations Information,” requires a quarterly analysis of events, both reportable and not reportable, for the previous 12 months. This report is the analysis of 76 occurrence reports and over 16 other deficiency reports (including not reportable events) identified at the INL during the period of October 2013 through December 2013. Battelle Energy Alliance (BEA) operates the INL under contract DE AC 07 051D14517

  20. Transverse flowmetry of carbon particles based on photoacoustic Doppler standard deviation using an auto-correlation method

    NASA Astrophysics Data System (ADS)

    Lu, Tao; Sun, Li-jun

    2015-05-01

    In order to measure the flow velocity of carbon particle suspension perpendicular to the receiving axis of ultrasound transducer, the standard deviation of photoacoustic Doppler frequency spectrum is used to estimate the bandwidth broadening, and the spectrum standard deviation is calculated by an auto-correlation method. A 532 nm pulsed laser with the repetition rate of 20 Hz is used as a pumping source to generate photoacoustic signal. The photoacoustic signals are detected using a focused PZT ultrasound transducer with the central frequency of 10 MHz. The suspension of carbon particles is driven by a syringe pump. The complex photoacoustic signal is calculated by Hilbert transformation from time domain signal before auto-correlation. The standard deviation of the Doppler bandwidth broadening is calculated by averaging the auto-correlation results of several individual A scans. The feasibility of the proposed method is demonstrated by measuring the spectrum standard deviation of the transversal carbon particle flow from 5.0 mm/s to 8.4 mm/s. The experimental results show that the auto-correlation result is approximately linearly distributed within the measuring range.

  1. National Institute for Rocket Propulsion Systems 1st Annual Workshop

    NASA Technical Reports Server (NTRS)

    Doreswamy, Rajiv; Fry, Emma; Swindell, Tina

    2012-01-01

    The National Institute for Rocket Propulsion Systems (NIRPS) is a Government -wide initiative that seeks to ensure the resiliency of the Nation fs rocket propulsion community in order for the enterprise to remain vibrant and capable of providing reliable and affordable propulsion systems for the nation fs defense, civil and commercial needs. Recognizing that rocket propulsion is a multi-use technology that ensures the nation fs leadership in aerospace, the Government has a vested interest in maintaining this strategic capability through coordinated and synchronized acquisition programs and continual investments in research and development. NIRPS is a resource for collaboration and integration between all sectors of the U.S. propulsion enterprise, supporting policy development options, identifying technology requirements, and offering solutions that maximize national resources while ensuring that capability exists to meet future demand. NIRPS functions as a multi ]agency organization that our nation fs decision makers can look to for comprehensive information regarding all issues concerning the propulsion enterprise.

  2. When should orthostatic blood pressure changes be evaluated in elderly: 1st, 3rd or 5th minute?

    PubMed

    Soysal, Pinar; Aydin, Ali Ekrem; Koc Okudur, Saadet; Isik, Ahmet Turan

    2016-01-01

    Detection of orthostatic hypotension (OH) is very important in geriatric practice, since OH is associated with mortality, ischemic stroke, falls, cognitive failure and depression. It was aimed to determine the most appropriate time for measuring blood pressure in transition from supine to upright position in order to diagnose OH in elderly. Comprehensive geriatric assessment (CGA) including Head up Tilt Table (HUT) test was performed in 407 geriatric patients. Orthostatic changes were assessed separately for the 1st, 3rd and 5th minutes (HUT1, HUT3 and HUT5, respectively) taking the data in supine position as the basis. The mean age, recurrent falls, presence of dementia and Parkinson's disease, number of drugs, alpha-blocker and anti-dementia drug use, and fasting blood glucose levels were significantly higher in the patients with versus without OH; whereas, albumin and 25-hydroxy vitamin D levels were significantly lower (p<0.05). However, different from HUT3 and HUT5, Charlson Comorbidity Index and the prevalence of diabetes mellitus were higher, the use of antidiabetics, antipsychotics, benzodiazepine, opioid and levodopa were more common (p<0.05). Statistical significance of the number of drugs and fasting blood glucose level was prominent in HUT1 as compared to HUT3 (p<0.01, p<0.05). Comparison of the patients that had OH only in HUT1, HUT3or HUT5 revealed no difference in terms of CGA parameters. These results suggests that orthostatic blood pressure changes determined at the 1st minute might be more important for geriatric practice. Moreover, 1st minute measurement might be more convenient in the elderly as it requires shorter time in practice.

  3. Evaluation of terrain complexity by autocorrelation. [geomorphology and geobotany

    NASA Technical Reports Server (NTRS)

    Craig, R. G.

    1982-01-01

    The topographic complexity of various sections of the Ozark, Appalachian, and Interior Low Plateaus, as well as of the New England, Piedmont, Blue Ridge, Ouachita, and Valley and Ridge Provinces of the Eastern United States were characterized. The variability of autocorrelation within a small area (7 1/2-ft quadrangle) to the variability at widely separated and diverse areas within the same physiographic region was compared to measure the degree of uniformity of the processes which can be expected to be encountered within a given physiographic province. The variability of autocorrelation across the eight geomorphic regions was compared and contrasted. The total study area was partitioned into subareas homogeneous in terrain complexity. The relation between the complexity measured, the geomorphic process mix implied, and the way in which geobotanical information is modified into a more or less recognizable entity is demonstrated. Sampling strategy is described.

  4. Comparison Autocorrelation Method and SVD Method for Plasma Mode Analysis in Tokamaks

    NASA Astrophysics Data System (ADS)

    Saadat, Shervin; Salem, Mohammad K.

    2011-08-01

    Autocorrelation method (Single time series) is new method for analysis of plasma mode in Tokamaks. In this article autocorrelation method has been compared with SVD method. Energy of the modes which obtained by SVD analysis showed that the autocorrelation method is a cited method for mode detection.

  5. Chaotic substitution for highly autocorrelated data in encryption algorithm

    NASA Astrophysics Data System (ADS)

    Anees, Amir; Siddiqui, Adil Masood; Ahmed, Fawad

    2014-09-01

    This paper addresses the major drawback of substitution-box in highly auto-correlated data and proposes a novel chaotic substitution technique for encryption algorithm to sort the problem. Simulation results reveal that the overall strength of the proposed technique for encryption is much stronger than most of the existing encryption techniques. Furthermore, few statistical security analyses have also been done to show the strength of anticipated algorithm.

  6. Velocity autocorrelation functions of Lennard-Jones fluids

    NASA Technical Reports Server (NTRS)

    Tsang, T.; Tang, H.

    1977-01-01

    By a self-consistent procedure, the velocity autocorrelation functions of both liquid and gaseous argon have been calculated without introducing any arbitrary parameters. The results are in satisfactory agreement with computer experiments. The correlation functions are primarily determined by the nearest-neighbor coordination. Because of the strong hard-core repulsion, the behaviors are more vibratory and damp out quickly at high densities and are more diffusive at lower densities.

  7. Digital grain-size analysis based on autocorrelation algorithm

    NASA Astrophysics Data System (ADS)

    Cheng, Zhixuan; Liu, Haijiang

    2015-08-01

    Grain size is one of the most important parameters in geology and coastal engineering. However, all traditional methods are time consuming, laborious, and expensive. In this study, the autocorrelation technique, which was first expounded by Rubin (2004), was extended to estimate the size of well-sorted sediments and the grain-size distribution of mixed-size sediments. Long and intermediate axes of well-sorted sediments ranging from 1 to 20 mm obtained from applying the autocorrelation method are compared with the corresponding results measured using a vernier caliper. Using the autocorrelation technique, the sediment mean size was calculated and was found to compare better with point counts than sieving. Regarding the mixed-size sediment, a nonlinear programming method, which is different from the conventional 'least-squares with non-negativity' method, the kernel density method, and the maximum entropy method, was used to obtain the representative grain sizes and associated sediment inherent parameters, such as mean diameter, median diameter, sorting, skewness, and kurtosis. Image pre-processing was used in the present analysis to enhance the contrast of the recorded image, and a conversion method applied to take into account the difference between the two-dimensional digital image method and the three-dimensional sieving method. Using the modified fitting points and the improved Gaussian function fitting method, the cumulative grain-size distribution curve and the probability density curve of the mixed-size sediments were obtained. The enhanced autocorrelation technique that was developed from the traditional 'look-up-catalogue' approach provided a more accurate estimation of the grain-size distribution, as well as the relevant physical parameters of the mixed-size sediment.

  8. Performance indicators for 1st quarter CY 1993

    SciTech Connect

    Not Available

    1993-08-01

    The Department of Energy (DOE) has established a Department-wide Performance Indicator (PI) Program for trending and analysis of operational data as directed by DOE Order 5480.26. The PI Program was established to provide a means for monitoring the environment, safety, and health (ES&H) performance of the DOE at the Secretary and other management levels. This is the ninth in a series of quarterly reports generated for the Department of Energy Field Office, Idaho (DOE-ID) by EG&G Idaho, Inc. to meet the requirements of the PI Program as directed by the DOE Standard. DOE-STD-1048-92 identifies four general areas of PIs. They are: Personnel Safety, Operational Incidents, Environment and Management. These four areas have been subdivided into 26 performance indicators. Approximately 115 performance indicator control and distribution charts comprise the body of this report A brief summary of PIs contained in each of these general areas is provided in the following pages. The four EG&G facilities whose performance is charted herein are as follows: (1) The Advanced Test Reactor (ATR); (2) The Radioactive Waste Management Complex (RWMC); (3) The Waste Experimental Reduction Facility (WERF) and (4) The Test Reactor Area (TRA) Hot Cells.

  9. Estimating the variation, autocorrelation, and environmental sensitivity of phenotypic selection.

    PubMed

    Chevin, Luis-Miguel; Visser, Marcel E; Tufto, Jarle

    2015-09-01

    Despite considerable interest in temporal and spatial variation of phenotypic selection, very few methods allow quantifying this variation while correctly accounting for the error variance of each individual estimate. Furthermore, the available methods do not estimate the autocorrelation of phenotypic selection, which is a major determinant of eco-evolutionary dynamics in changing environments. We introduce a new method for measuring variable phenotypic selection using random regression. We rely on model selection to assess the support for stabilizing selection, and for a moving optimum that may include a trend plus (possibly autocorrelated) fluctuations. The environmental sensitivity of selection also can be estimated by including an environmental covariate. After testing our method on extensive simulations, we apply it to breeding time in a great tit population in the Netherlands. Our analysis finds support for an optimum that is well predicted by spring temperature, and occurs about 33 days before a peak in food biomass, consistent with what is known from the biology of this species. We also detect autocorrelated fluctuations in the optimum, beyond those caused by temperature and the food peak. Because our approach directly estimates parameters that appear in theoretical models, it should be particularly useful for predicting eco-evolutionary responses to environmental change.

  10. [Yersinia enterocolitica: 1st isolation from meat products in Argentina].

    PubMed

    de Guzmán, A M; de Pederiva, N B; Torres, C N; Eiguer, T; Giménez, D F

    1984-01-01

    A search for Y. enterocolitica in fresh foods of animal origin has been carried out. Isolations were obtained from "chorizos" (thick fresh sausages), "salchichas" (slender fresh sausages), bovine and pig's tongues and caecum (Tables 1, 2). Enrichments were performed in saline phosphate buffer 0.067 M, pH 7.6 and nutrient broth with 0.5% glucose. Caecum and tongue samples were postenriched in 0.5% KOH. Subcultures were done in Salmonella-Shigella agar, MacConkey agar and eosin-methylene blue agar. Isolates were identified through biochemical, serological and lysotyping methods. The following biotypes (B), serotypes (O) and lysotypes (Lis) were isolated: from "chorizos", B2, 0:9, Lis X3 and B1, 0:7,8, Lis Xo. From "salchichas", B1, 0:5, Lis Xz. From bovine tongues, B1, 0:5, Lis Xz and B2, 0:9, Lis X3. From pig tongues, B1, 0:6, Lis Xz. From pig caecum, B1, 0:6, Lis Xz and B1, 0:5, Lis Xz. Serotype B2, 0:9, Lis X3 isolated from "chorizos" and bovine tongues has been only exceptionally found outside of human beings. Serotype B1, 0:6, Liz Xz was isolated from the tongue and caecum of one pig. From the caecum of another pig two serotypes, B1, 0:5, Liz Xz and B1, 0:6, Liz Xz, were isolated. In order to determine the importance of Y. entercolitica as etiologic agent of yersiniosis in Argentina, further studies on the frequency and distribution of this agent are recommended.

  11. "European Resuscitation Council 2015 burn 1st Aid recommendations-concerns and issues for first responders".

    PubMed

    Goodwin, Nicholas S

    2016-08-01

    As the lead author of a recently published systematic review on hydrogel burn dressings in pre-hospital, I was alarmed to read the claim by the authors to the effect no one method of burn wound cooling was superior to any other; "There is no evidence to recommend a specific temperature or method of cooling". The reputation and prominence of the ERC within the circle of resuscitation councils now delving into 1st Aid recommendations leads to the conclusion that misguided recommendations may cause confusion amongst first responders, may falsely misdirect 1st Aid providers to unsupported practices or alternatively create a window of opportunity for marketers or sellers of alternative burn 1st Aid technologies to make unsupported claims in respect of comparable efficacy of their own product versus "traditional" methods.

  12. Study of trabecular bone microstructure using spatial autocorrelation analysis

    NASA Astrophysics Data System (ADS)

    Wald, Michael J.; Vasilic, Branimir; Saha, Punam K.; Wehrli, Felix W.

    2005-04-01

    The spatial autocorrelation analysis method represents a powerful, new approach to quantitative characterization of structurally quasi-periodic anisotropic materials such as trabecular bone (TB). The method is applicable to grayscale images and thus does not require any preprocessing, such as segmentation which is difficult to achieve in the limited resolution regime of in vivo imaging. The 3D autocorrelation function (ACF) can be efficiently calculated using the Fourier transform. The resulting trabecular thickness and spacing measurements are robust to the presence of noise and produce values within the expected range as determined by other methods from μCT and μMRI datasets. TB features found from the ACF are shown to correlate well with those determined by the Fuzzy Distance transform (FDT) in the transverse plane, i.e. the plane orthogonal to bone"s major axis. The method is further shown to be applicable to in-vivo μMRI data. Using the ACF, we examine data acquired in a previous study aimed at evaluating the structural implications of male hypogonadism characterized by testosterone deficiency and reduced bone mass. Specifically, we consider the hypothesis that eugonadal and hypogonadal men differ in the anisotropy of their trabecular networks. The analysis indicates a significant difference in trabecular bone thickness and longitudinal spacing between the control group and the testosterone deficient group. We conclude that spatial autocorrelation analysis is able to characterize the 3D structure and anisotropy of trabecular bone and provides new insight into the structural changes associated with osteoporotic trabecular bone loss.

  13. Size determinations of plutonium colloids using autocorrelation photon spectroscopy

    SciTech Connect

    Triay, I.R.; Rundberg, R.S.; Mitchell, A.J.; Ott, M.A.; Hobart, D.E.; Palmer, P.D.; Newton, T.W.; Thompson, J.L.

    1989-12-01

    Autocorrelation Photon Spectroscopy (APS) is a light-scattering technique utilized to determine the size distribution of colloidal suspensions. The capabilities of the APS methodology have been assessed by analyzing colloids of known sizes. Plutonium(IV) colloid samples were prepared by a variety of methods including: dilution; peptization; and alpha-induced auto-oxidation of Pu(III). The size of theses Pu colloids was analyzed using APS. The sizes determined for the Pu colloids studied varied from 1 to 370 nanometers. 7 refs., 5 figs., 3 tabs.

  14. Autocorrelation-based time synchronous averaging for condition monitoring of planetary gearboxes in wind turbines

    NASA Astrophysics Data System (ADS)

    Ha, Jong M.; Youn, Byeng D.; Oh, Hyunseok; Han, Bongtae; Jung, Yoongho; Park, Jungho

    2016-03-01

    We propose autocorrelation-based time synchronous averaging (ATSA) to cope with the challenges associated with the current practice of time synchronous averaging (TSA) for planet gears in planetary gearboxes of wind turbine (WT). An autocorrelation function that represents physical interactions between the ring, sun, and planet gears in the gearbox is utilized to define the optimal shape and range of the window function for TSA using actual kinetic responses. The proposed ATSA offers two distinctive features: (1) data-efficient TSA processing and (2) prevention of signal distortion during the TSA process. It is thus expected that an order analysis with the ATSA signals significantly improves the efficiency and accuracy in fault diagnostics of planet gears in planetary gearboxes. Two case studies are presented to demonstrate the effectiveness of the proposed method: an analytical signal from a simulation and a signal measured from a 2 kW WT testbed. It can be concluded from the results that the proposed method outperforms conventional TSA methods in condition monitoring of the planetary gearbox when the amount of available stationary data is limited.

  15. Broadband short pulse measurement by autocorrelation with a sum-frequency generation set-up

    SciTech Connect

    Glotin, F.; Jaroszynski, D.; Marcouille, O.

    1995-12-31

    Previous spectral and laser pulse length measurements carried out on the CLIO FEL at wavelength {lambda}=8.5 {mu}m suggested that very short light pulses could be generated, about 500 fs wide (FWHM). For these measurements a Michelson interferometer with a Te crystal, as a non-linear detector, was used as a second order autocorrelation device. More recent measurements in similar conditions have confirmed that the laser pulses observed are indeed single: they are not followed by other pulses distant by the slippage length N{lambda}. As the single micropulse length is likely to depend on the slippage, more measurements at different wavelengths would be useful. This is not directly possible with our actual interferometer set-up, based on a phase-matched non-linear crystal. However, we can use the broadband non-linear medium provided by one of our users` experiments: Sum-Frequency Generation over surfaces. With such autocorrelation set-up, interference fringes are no more visible, but this is largely compensated by the frequency range provided. First tests at 8 {mu}m have already been performed to validate the technic, leading to results similar to those obtained with our previous Michelson set-up.

  16. Autocorrelation in ultraviolet radiation measured at ground level using detrended fluctuation analysis

    NASA Astrophysics Data System (ADS)

    da Silva Filho, Paulo Cavalcante; da Silva, Francisco Raimundo; Corso, Gilberto

    2016-07-01

    In this study, we analyzed the autocorrelation among four ultraviolet (UV) radiation data sets obtained at 305 nm, 320 nm, 340 nm, and 380 nm. The data were recorded at ground level at the INPE climate station in Natal, RN, Brazil, which is a site close to the equator. The autocorrelations were computed by detrended fluctuation analysis (DFA) to estimate the index α. We found that the ​fluctuations in the UV radiation data were fractal, with scale-free behavior at a DFA index α ≃ 0.7. In addition, we performed a power law spectral analysis, which showed that the power spectrum exhibited a power law behavior with an exponent of β ≃ 0.45. Given that the theoretical result is β = 2 α - 1, these two results are in good agreement. Moreover, the application of the DFA ​method to the UV radiation data required detrending using a polynomial with an order of at least eight, which was related to the complex daily solar radiation curve obtained at ground level in a tropical region. The results indicated that the α exponent of UV radiation is similar to other climatic records such as air temperature, wind, or rain, but not solar activity.

  17. Aedes aegypti pharate 1st instar quiescence: a case for anticipatory reproductive plasticity.

    PubMed

    Perez, Mario H; Noriega, Fernando G

    2013-03-01

    Aedes aegypti mosquitoes use pharate 1st instar quiescence to cope with fluctuations in water availability hosting a fully developed 1st instar larvae within the chorion. The duration of this quiescence has been shown to affect larval fitness. This study sought to determine if an extended egg quiescence can elicit a plastic response resulting in an adult phenotype distinct from adults reared from short quiescence eggs. Our findings indicate that extended pharate 1st instar quiescence affects the performance and reproductive fitness of the adult female mosquito as well as the nutritional status of its progeny via maternal effects in an adaptive manner. This study demonstrates that phenotypic plasticity results as a consequence of the duration of pharate 1st instar quiescence and alternative phenotypes may exist for this mosquito with quiescence serving as a cue possibly signaling the environmental conditions that follow a dry period. These findings have implications for A. aegypti's success as a vector, geographic distribution, vector capacity and control.

  18. Highlights of the 1st Student Symposium of the ISCB RSG UK

    PubMed Central

    Rahman, Farzana; Farmer, Rohit; Das, Sayoni; Vayani, Fatima; Hassan, Mehedi

    2015-01-01

    This short report summarises the scientific content and activities of a student-led event, the 1st student symposium by the UK Regional Student Group of the International Society for Computational Biology. The event took place on the 8th of October 2014. PMID:26998223

  19. 25. PRIMARY POWER TRANSMISSION BELT HOLES IN 1st FLOOR MILL ...

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

    25. PRIMARY POWER TRANSMISSION BELT HOLES IN 1st FLOOR MILL NO. 1 CEILING. WATER-POWERED MACHINERY LOCATED IN BASEMENT RAN LEATHER BELTS THROUGH THESE HOLES. POWER WAS THEN TRANSMITTED TO SHAFTS AND PULLEYS TO RUN MACHINERY ON MILL FLOORS. - Prattville Manufacturing Company, Number One, 242 South Court Street, Prattville, Autauga County, AL

  20. 24. OVERALL OF 1st FLOOR OF MILL NO. 1. PALLETS ...

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

    24. OVERALL OF 1st FLOOR OF MILL NO. 1. PALLETS HELD CLOTH IN STORAGE IN LATE 20th CENTURY. IRON POSTS IN LEFT DISTANCE FRONTED CLOTH BINS. HISTORIAN LEEANN LANDS IN BACKGROUND WITH LIGHT. - Prattville Manufacturing Company, Number One, 242 South Court Street, Prattville, Autauga County, AL

  1. The Student View of 1st Year Laboratory Work in the Biosciences--Score Gamma?

    ERIC Educational Resources Information Center

    Collis, Mike; Gibson, Alan; Hughes, Ian; Sayers, Gill; Todd, Martin

    2008-01-01

    Students registered on 1st year bioscience courses in 9 universities were surveyed for their views on the laboratory classes they were taking. Returns were obtained from 695 (70%). Student views were varied, some viewing particular features of laboratory classes as "good" while others viewed the same features as "bad". Students…

  2. 48. MISSISSIPPI, LOWNDES CO. COLUMBUS RAILROAD BRIDGE End of 1st ...

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

    48. MISSISSIPPI, LOWNDES CO. COLUMBUS RAILROAD BRIDGE End of 1st St. S., Columbus, Ms Latching mechanism, E end of turn span, view from N. Sarcone Photography, Columbus, MS. Sep 1978. - Bridges of the Upper Tombigbee River Valley, Columbus, Lowndes County, MS

  3. 49. MISSISSIPPI, LOWNDES CO. COLUMBUS RAILROAD BRIDGE End of 1st ...

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

    49. MISSISSIPPI, LOWNDES CO. COLUMBUS RAILROAD BRIDGE End of 1st St. S., Columbus, Ms. Top of pier and underside of w end of turn span. Sarcone Photography, Columbus, Ms. Sep 1978. - Bridges of the Upper Tombigbee River Valley, Columbus, Lowndes County, MS

  4. 47. MISSISSIPPI, LOWNDES CO. COLUMBUS RAILROAD BRIDGE End of 1st ...

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

    47. MISSISSIPPI, LOWNDES CO. COLUMBUS RAILROAD BRIDGE End of 1st St. S., Columbus, Ms. Latching mechanism, E end of turn span, viewed from W. Sarcone Photography, Columbus, Ms. Sep 1978. - Bridges of the Upper Tombigbee River Valley, Columbus, Lowndes County, MS

  5. 42. MISSISSIPPI, LOWNDES CO. COLUMBUS RAILROAD BRIDGE End of 1st ...

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

    42. MISSISSIPPI, LOWNDES CO. COLUMBUS RAILROAD BRIDGE End of 1st St. S., Columbus, Ms. Copy of postcard ca. 1900. Copy owned and made by Jack Donnell, Columbus, Ms. Shows two-span steel truss, built by Phoenix Bridge Co. in 1878. Negative copied by: Sarcone Photography, Columbus, Ms. Sep 1978. - Bridges of the Upper Tombigbee River Valley, Columbus, Lowndes County, MS

  6. Plasmodium falciparum malaria in 1(st)-2(nd) century CE southern Italy.

    PubMed

    Marciniak, Stephanie; Prowse, Tracy L; Herring, D Ann; Klunk, Jennifer; Kuch, Melanie; Duggan, Ana T; Bondioli, Luca; Holmes, Edward C; Poinar, Hendrik N

    2016-12-05

    The historical record attests to the devastation malaria exacted on ancient civilizations, particularly the Roman Empire [1]. However, evidence for the presence of malaria during the Imperial period in Italy (1st-5th century CE) is based on indirect sources, such as historical, epigraphic, or skeletal evidence. Although these sources are crucial for revealing the context of this disease, they cannot establish the causative species of Plasmodium. Importantly, definitive evidence for the presence of malaria is now possible through the implementation of ancient DNA technology. As malaria is presumed to have been at its zenith during the Imperial period [1], we selected first or second molars from 58 adults from three cemeteries from this time: Isola Sacra (associated with Portus Romae, 1st-3rd century CE), Velia (1st-2nd century CE), and Vagnari (1st-4th century CE). We performed hybridization capture using baits designed from the mitochondrial (mtDNA) genomes of Plasmodium spp. on a prioritized subset of 11 adults (informed by metagenomic sequencing). The mtDNA sequences generated provided compelling phylogenetic evidence for the presence of P. falciparum in two individuals. This is the first genomic data directly implicating P. falciparum in Imperial period southern Italy in adults.

  7. Perceptual Narrowing of Linguistic Sign Occurs in the 1st Year of Life

    ERIC Educational Resources Information Center

    Palmer, Stephanie Baker; Fais, Laurel; Golinkoff, Roberta Michnick; Werker, Janet F.

    2012-01-01

    Over their 1st year of life, infants' "universal" perception of the sounds of language narrows to encompass only those contrasts made in their native language (J. F. Werker & R. C. Tees, 1984). This research tested 40 infants in an eyetracking paradigm and showed that this pattern also holds for infants exposed to seen language--American Sign…

  8. 77 FR 22574 - Filing Dates for the Washington Special Election In the 1st Congressional District

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-16

    ... From the Federal Register Online via the Government Publishing Office FEDERAL ELECTION COMMISSION Filing Dates for the Washington Special Election In the 1st Congressional District AGENCY: Federal Election Commission. ACTION: Notice of filing dates for special election. SUMMARY: Washington has...

  9. Breaking Down Barriers for 1st-Year Teachers: What Teacher Preparation Programs Can Do

    ERIC Educational Resources Information Center

    Brashier, Allison; Norris, Elizabeth

    2008-01-01

    A developmentally appropriate learning environment for young children is vital for successful learning. However, implementing developmentally appropriate practices can be a challenge for 1st-year teachers because of the pressures of standardized testing. The purpose of this study was to examine the struggles teachers encounter in implementing…

  10. The Course of Psychological Disorders in the 1st Year After Cancer Diagnosis

    ERIC Educational Resources Information Center

    Kangas, Maria; Henry, Jane L.; Bryant, Richard A.

    2005-01-01

    This study investigated the relationship between acute stress disorder (ASD) and posttraumatic stress disorder (PTSD) and comorbid anxiety, depressive, and substance use disorders over the first 12-month period following a cancer diagnosis. Individuals recently diagnosed with 1st onset head and neck or lung malignancy were assessed for ASD within…

  11. 75 FR 12544 - Filing Dates for the Hawaii Special Election In the 1st Congressional District

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-16

    ... Filing Dates for the Hawaii Special Election In the 1st Congressional District AGENCY: Federal Election Commission. ACTION: Notice of filing dates for special election. SUMMARY: Hawaii has scheduled a Special... Campaign Committees All principal campaign committees of candidates who participate in the Hawaii...

  12. 130. Post1911. Photograph labeled, 'SEASON 1913. CAPTAIN, 1st MATE, SUPT ...

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

    130. Post-1911. Photograph labeled, 'SEASON 1913. CAPTAIN, 1st MATE, SUPT AND STOREKEEPER, A.P. ASS'N CANNERY, SHIP STAR OF ALASKA.' View forward from mizzenmast, post side. - Ship BALCLUTHA, 2905 Hyde Street Pier, San Francisco, San Francisco County, CA

  13. How Many Attempts Until Success in Some Core 1st. Year Disciplines?

    ERIC Educational Resources Information Center

    Fernandes, Graça Leão; Andrade e Silva, João; Lopes, Margarida Chagas

    2012-01-01

    Due to a general development in education brought about by democracy, Portugal has witnessed tremendous development in Higher Education (HE) since the beginning of the 1980s. Nevertheless, the percentage of graduates among the Portuguese population still ranks far below most European countries. This is why academic performance in HE 1st cycle…

  14. The autocorrelation function of the North Pole dust

    NASA Technical Reports Server (NTRS)

    Knude, Jens

    1989-01-01

    The angular scales on which local interstellar dust is distributed are so far rather unknown as are the geometrical shapes of the dust features. From the about 5000 color excesses resulting from a north polar survey with 4 to 5 stars per square degree the two-point autocorrelation function is derived for separations ranging from 10 min to 3 deg. For intercloud lines of sight, -0.020 is less than E(b - y) is less than -0.010 mag, the average cross products (E sub 1 x E sub 2)(sub theta) show no variation with separation theta(1,2) whereas products of cloud column densities, 0.030 is less than E(b - y) is less than 0.040 mag, seem to prefer discrete separations either less than 20 min, around 75 min, or finally at about 150 min. Surprisingly the two point autocorrelation function omega(sub E) = E(sub 1) x E(sub 2)/E squared - 1 equals 0 except for any separation except theta = 0. Omega(sub E)(theta)'s absence of variation is unexpected because omega(sub H)(theta) is known to vary exponentially above b = 40 deg for separations less than 3 deg. Atomic hydrogen and dust may thus not be entirely mixed or the moments (E sub 1 x E sub 2)(sub theta) may not characterize the dust distribution.

  15. Zero crossings properties of a narrow band process to determine the reliability of a two frequency encoding - Application to evaluating its autocorrelation envelope

    NASA Astrophysics Data System (ADS)

    Hay, J.

    1980-09-01

    The development of an appropriate mathematical model of narrow band Gaussian noise zero crossings was required in order to facilitate the calibration of electronic equipment detecting two-frequency codes used on single track tape recordings with a wide dynamic range, and to find out its decoding reliability. The possibilities of evaluating the autocorrelation envelope is also mentioned.

  16. Zero crossings properties of a narrow-band process to determine the reliability of a two-frequency encoding - Application to evaluating its autocorrelation envelope

    NASA Astrophysics Data System (ADS)

    Hay, J.

    1980-08-01

    The development of an appropriate mathematical model of narrow band Gaussian noise zero crossings was required in order to facilitate the calibration of electronic equipment detecting two-frequency codes used on single track tape recordings with a wide dynamic range, and to find out its decoding reliability. The possibilities of evaluating the autocorrelation envelope is also mentioned.

  17. Low power autocorrelation technique based on the degree-of-polarization measurement

    NASA Astrophysics Data System (ADS)

    Hu, Junhao; Yu, Changyuan

    2010-12-01

    Based on the degree-of-polarization (DOP) measurement, an autocorrelation technique to measure the pulse width of chirp-free optical short pulse with a very low optical power (<-60 dBm) is demonstrated. The impacts of chirp and misalignment of the input light are also discussed in detail. The pulse width measurement results are consistent with the conventional second-harmonic generation (SHG) autocorrelation, while our autocorrelation technique does not require high input power or rigid optical alignment.

  18. A two-photon fluorescence autocorrelator for a Nd:YLF modelocked laser

    SciTech Connect

    Kner, P.A.

    1991-05-01

    In this thesis, I discuss the design and implementation of an autocorrelator for an actively modelocked ND:YLF laser at wavelength 1.054{mu}m. A dye is used to generate a broadband two-photon fluorescence (TPF) signal at 570nm which is the autocorrelation of the laser pulses. Two different techniques are discussed. A colliding pulse scheme can be used to generate a TPF autocorrelation signal as a function of distance, or an interferometer technique can be used to generate an autocorrelation signal as a function of the delay in an interferometer arm. Experimental results are discussed, but they are inconclusive because of difficulties in interpreting the signal.

  19. Simple autocorrelator for ultraviolet pulse-width measurements based on the nonlinear photoelectric effect.

    PubMed

    Takagi, Y

    1994-09-20

    An optical pulse-width measurement in the ultraviolet spectral region has been performed in a simple manner by introducing into the second-order autocorrelator a nonlinear response of the optical detector based on the two-photon photoelectric effect. The pulse widths of the third, fourth, and fifth harmonics of a mode-locked Nd:YAG laser were measured by the use of a photomultiplier with a cesium iodide photocathode with a minimum required pulse energy of 10 nJ and a power density of 10 kW/cm(2). The effect of transient interband optical excitation with different photon energies on the intensity correlation profile was also studied for the case of a copper iodide photocathode, and the result provides a background-free intensity correlation in a part of the ultraviolet spectral region.

  20. Cryptanalyzing a chaotic encryption algorithm for highly autocorrelated data

    NASA Astrophysics Data System (ADS)

    Li, Ming; Liu, Shangwang; Niu, Liping; Liu, Hong

    2016-12-01

    Recently, a chaotic encryption algorithm for highly autocorrelated data was proposed. By adding chaotic diffusion to the former work, the information leakage of the encryption results especially for the images with lower gray scales was eliminated, and both higher-level security and fast encryption time were achieved. In this study, we analyze the security weakness of this scheme. By applying the ciphertext-only attack, the encrypted image can be restored into the substituted image except for the first block; and then, by using the chosen-plaintext attack, the S-boxes, the distribution map, and the block of chaotic map values, can all be revealed, and the encrypted image can be completely cracked. The improvement is also proposed. Experimental results verify our assertion.

  1. A linear regression solution to the spatial autocorrelation problem

    NASA Astrophysics Data System (ADS)

    Griffith, Daniel A.

    The Moran Coefficient spatial autocorrelation index can be decomposed into orthogonal map pattern components. This decomposition relates it directly to standard linear regression, in which corresponding eigenvectors can be used as predictors. This paper reports comparative results between these linear regressions and their auto-Gaussian counterparts for the following georeferenced data sets: Columbus (Ohio) crime, Ottawa-Hull median family income, Toronto population density, southwest Ohio unemployment, Syracuse pediatric lead poisoning, and Glasgow standard mortality rates, and a small remotely sensed image of the High Peak district. This methodology is extended to auto-logistic and auto-Poisson situations, with selected data analyses including percentage of urban population across Puerto Rico, and the frequency of SIDs cases across North Carolina. These data analytic results suggest that this approach to georeferenced data analysis offers considerable promise.

  2. Fractal analysis of multiscale spatial autocorrelation among point data

    USGS Publications Warehouse

    De Cola, L.

    1991-01-01

    The analysis of spatial autocorrelation among point-data quadrats is a well-developed technique that has made limited but intriguing use of the multiscale aspects of pattern. In this paper are presented theoretical and algorithmic approaches to the analysis of aggregations of quadrats at or above a given density, in which these sets are treated as multifractal regions whose fractal dimension, D, may vary with phenomenon intensity, scale, and location. The technique is illustrated with Matui's quadrat house-count data, which yield measurements consistent with a nonautocorrelated simulated Poisson process but not with an orthogonal unit-step random walk. The paper concludes with a discussion of the implications of such analysis for multiscale geographic analysis systems. -Author

  3. An autocorrelation method to detect low frequency earthquakes within tremor

    USGS Publications Warehouse

    Brown, J.R.; Beroza, G.C.; Shelly, D.R.

    2008-01-01

    Recent studies have shown that deep tremor in the Nankai Trough under western Shikoku consists of a swarm of low frequency earthquakes (LFEs) that occur as slow shear slip on the down-dip extension of the primary seismogenic zone of the plate interface. The similarity of tremor in other locations suggests a similar mechanism, but the absence of cataloged low frequency earthquakes prevents a similar analysis. In this study, we develop a method for identifying LFEs within tremor. The method employs a matched-filter algorithm, similar to the technique used to infer that tremor in parts of Shikoku is comprised of LFEs; however, in this case we do not assume the origin times or locations of any LFEs a priori. We search for LFEs using the running autocorrelation of tremor waveforms for 6 Hi-Net stations in the vicinity of the tremor source. Time lags showing strong similarity in the autocorrelation represent either repeats, or near repeats, of LFEs within the tremor. We test the method on an hour of Hi-Net recordings of tremor and demonstrates that it extracts both known and previously unidentified LFEs. Once identified, we cross correlate waveforms to measure relative arrival times and locate the LFEs. The results are able to explain most of the tremor as a swarm of LFEs and the locations of newly identified events appear to fill a gap in the spatial distribution of known LFEs. This method should allow us to extend the analysis of Shelly et al. (2007a) to parts of the Nankai Trough in Shikoku that have sparse LFE coverage, and may also allow us to extend our analysis to other regions that experience deep tremor, but where LFEs have not yet been identified. Copyright 2008 by the American Geophysical Union.

  4. 44. MISSISSIPPI, LOWNDES CO. COLUMBUS RAILROAD BRIDGE End of 1st ...

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

    44. MISSISSIPPI, LOWNDES CO. COLUMBUS RAILROAD BRIDGE End of 1st St. S., Columbus, Ms. Detail from Camille Drie's map: A Bird's Eye View of Columbus, Mississippi ca. 1875-76. Shows M&O RR bridge before the Phoenix Bridge Co. erected iron truss spans in 1878. Credit: Photostat of map in Lowndes Co. Public Library Sarcone Photography, Columbus, Ms. 1978. - Bridges of the Upper Tombigbee River Valley, Columbus, Lowndes County, MS

  5. Aedes aegypti pharate 1st instar quiescence affects larval fitness and metal tolerance.

    PubMed

    Perez, Mario H; Noriega, Fernando G

    2012-06-01

    The eggs of the mosquito Aedes aegypti possess the ability to undergo an extended quiescence hosting a fully developed 1st instar larvae within the chorion. As a result of this life history trait pharate larvae can withstand months of quiescence inside the egg where they depend on stored maternal reserves. A. aegypti mosquitoes are frequently associated with urban habitats that may contain significant metal pollution. Therefore, the duration of quiescence and extent of nutritional depletion may affect the physiology and survival of larvae that hatch in a suboptimal habitat. The aim of this study was to determine the effect of an extended quiescence on larval nutrient reserves and the subsequent effects of metal exposure on larval fitness, survival and development. We hypothesized that an extended quiescence would reduce nutritional reserves and alter the molecular response to metal exposure thereby reducing larval survival and altering larval development. As a molecular marker for metal stress responses, we evaluated transcriptional changes in the metallothionein gene (AaMtn) in response to quiescence and metal exposure. Extended 1st instar quiescence resulted in a significant decrease in lipid reserves and negatively affected larval fitness and development. AaMtn transcription and metal tolerance were compromised in first instars emerged from eggs that had undergone an extended quiescence. These findings suggest that newly emerged mosquito larvae that had survived a relatively long pharate 1st instar quiescence (as might occur during a dry season) are more vulnerable to environmental stress. Pharate 1st instar quiescence could have implications for vector control strategies. Newly emerged mosquito larvae at the end of the dry season or start of the wet season are physiologically compromised, and therefore potentially more susceptible to vector control strategies than mosquito larvae hatched subsequently throughout the wet season.

  6. 7. Photographic copy of original construction drawing, ELECTRICAL 1ST AND ...

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

    7. Photographic copy of original construction drawing, ELECTRICAL 1ST AND 2ND FLOOR PLANS, SHEET 10 of 11, DRAWING NO. 35-03-05 SF 5/1677, U.S. Army Engineer District, Detroit, Corps of Engineers, 9 June, 1959, on file Selfridge Base Museum. - Selfridge Field, Building No. 1041, West of E Street, north of D Street, Mount Clemens, Macomb County, MI

  7. 46. NORTH END OF MILL NO. 2, 1st FLOOR, BELOW ...

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

    46. NORTH END OF MILL NO. 2, 1st FLOOR, BELOW PICKER AND CLOTH ROOM AREA. FUNCTION OF THIS SPACE UNKNOWN AT PRESENT. NOTE THAT EYE BEAM REPLACES ORIGINAL WALL OF 1892 PICKER HOUSE. CENTER (OR LEFT) DOOR IS ENTRY TO MILL NO. 2. RIGHT DOOR IS ENTRY TO 1892 NAPPER ROOM. - Prattville Manufacturing Company, Number One, 242 South Court Street, Prattville, Autauga County, AL

  8. 43. MISSISSIPPI, LOWNDES CO. COLUMBUS RAILROAD BRIDGE End of 1st ...

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

    43. MISSISSIPPI, LOWNDES CO. COLUMBUS RAILROAD BRIDGE End of 1st St. S., Columbus, Ms. Copy of photo 1900. Shows 1878 M&O RR bridge. The steamboat, 'Gopher,' in foreground, was an archeological survey vessel from the Franklin Institute in Philadelphia. Published in Art in Mississippi (1901). Credit: Copied from print in Lowndes Co. Public Library by Sarcone Photography, Columbus, Ms. 1978. - Bridges of the Upper Tombigbee River Valley, Columbus, Lowndes County, MS

  9. Ruthenium indenylidene “1st generation” olefin metathesis catalysts containing triisopropyl phosphite

    PubMed Central

    Guidone, Stefano; Nahra, Fady; Slawin, Alexandra M Z

    2015-01-01

    Summary The reaction of triisopropyl phosphite with phosphine-based indenylidene pre-catalysts affords “1st generation” cis-complexes. These have been used in olefin metathesis reactions. The cis-Ru species exhibit noticeable differences with the trans-Ru parent complexes in terms of structure, thermal stability and reactivity. Experimental data underline the importance of synergistic effects between phosphites and L-type ligands. PMID:26425210

  10. Seismic ambient noise H/V spectral ratio using the ACA (autocorrelations of coda of autocorrelations) approach

    NASA Astrophysics Data System (ADS)

    Sanchez-Sesma, F. J.; Piña, J.; Campillo, M.; Luzón, F.; García-Jerez, A.; Albarello, D.; Lunedei, E.

    2012-12-01

    The seismic ambient noise horizontal-to-vertical spectral ratios (NHVSR) are valuable for microzonation, and seismic prospecting. This is particularly true for low-cost dense spatial sampling projects. Arai and Tokimatsu (2004) proposed to use average energy densities to compose the ratios. It means that H/V comes from the square root of the ratio of averages. On the other hand, a popular approach makes the average of spectral ratios. For ergodic processes peak values are usually the same using these two approaches. Sometimes however, the observations are insufficient and computed values for low frequencies display large variability and the corresponding H/V estimates may be inaccurate. The bias caused by localized sources may be the source of errors in the estimates. In this work we propose to compute the NHVSR using the Autocorrelations of Coda of Autocorrelations. This ACA approach is inspired in the work by Stehly et al. (2008). They used the Correlations of Coda of Correlations (C3) to isotropize the field. In our ACA approach the whole time series, say of 30 minutes, for each component is autocorrelated and the averages of the spectral density of selected windows (late coda windows are eliminated) are then improved estimates of directional energy densities. The computation of NHVSR using ACA appears more stable and free of transient effects. It remains to establish how this may be accounted for in forward calculation of H/V spectral ratios for models like a layered medium (e.g. Sánchez-Sesma et al., 2011; Albarello and Lunedei, 2011). This will require further scrutiny. References. Albarello, D. & E. Lunedei (2011). Structure of ambient vibration wavefield in the frequency range of engineering interest ([0.5, 20] Hz): insights from numerical modelling. Near Surface Geophysics 9, 543-559. Arai, H. & K. Tokimatsu (2004). S-wave velocity profiling by inversion of microtremor H/V spectrum, Bull. Seismol. Soc. Am. 94, 53-63. Sánchez-Sesma, F. J., M. Rodr

  11. Autocorrelated residuals in inverse modelling of soil hydrological processes: a reason for concern or something that can safely be ignored?

    NASA Astrophysics Data System (ADS)

    Scharnagl, Benedikt; Durner, Wolfgang

    2013-04-01

    Models are inherently imperfect because they simplify processes that are themselves imperfectly known and understood. Moreover, the input variables and parameters needed to run a model are typically subject to various sources of error. As a consequence of these imperfections, model predictions will always deviate from corresponding observations. In most applications in soil hydrology, these deviations are clearly not random but rather show a systematic structure. From a statistical point of view, this systematic mismatch may be a reason for concern because it violates one of the basic assumptions made in inverse parameter estimation: the assumption of independence of the residuals. But what are the consequences of simply ignoring the autocorrelation in the residuals, as it is current practice in soil hydrology? Are the parameter estimates still valid even though the statistical foundation they are based on is partially collapsed? Theory and practical experience from other fields of science have shown that violation of the independence assumption will result in overconfident uncertainty bounds and that in some cases it may lead to significantly different optimal parameter values. In our contribution, we present three soil hydrological case studies, in which the effect of autocorrelated residuals on the estimated parameters was investigated in detail. We explicitly accounted for autocorrelated residuals using a formal likelihood function that incorporates an autoregressive model. The inverse problem was posed in a Bayesian framework, and the posterior probability density function of the parameters was estimated using Markov chain Monte Carlo simulation. In contrast to many other studies in related fields of science, and quite surprisingly, we found that the first-order autoregressive model, often abbreviated as AR(1), did not work well in the soil hydrological setting. We showed that a second-order autoregressive, or AR(2), model performs much better in these

  12. MATLAB-Based Program for Teaching Autocorrelation Function and Noise Concepts

    ERIC Educational Resources Information Center

    Jovanovic Dolecek, G.

    2012-01-01

    An attractive MATLAB-based tool for teaching the basics of autocorrelation function and noise concepts is presented in this paper. This tool enhances traditional in-classroom lecturing. The demonstrations of the tool described here highlight the description of the autocorrelation function (ACF) in a general case for wide-sense stationary (WSS)…

  13. An updated perspective on the role of environmental autocorrelation in animal populations.

    PubMed

    Ferguson, Jake M; Carvalho, Felipe; Murillo-García, Oscar; Taper, Mark L; Ponciano, José M

    2016-06-01

    Ecological theory predicts that the presence of temporal autocorrelation in environments can considerably affect population extinction risk. However, empirical estimates of autocorrelation values in animal populations have not decoupled intrinsic growth and density feedback processes from environmental autocorrelation. In this study we first discuss how the autocorrelation present in environmental covariates can be reduced through nonlinear interactions or by interactions with multiple limiting resources. We then estimated the degree of environmental autocorrelation present in the Global Population Dynamics Database using a robust, model-based approach. Our empirical results indicate that time series of animal populations are affected by low levels of environmental autocorrelation, a result consistent with predictions from our theoretical models. Claims supporting the importance of autocorrelated environments have been largely based on indirect empirical measures and theoretical models seldom anchored in realistic assumptions. It is likely that a more nuanced understanding of the effects of autocorrelated environments is necessary to reconcile our conclusions with previous theory. We anticipate that our findings and other recent results will lead to improvements in understanding how to incorporate fluctuating environments into population risk assessments.

  14. Proposal of a new autocorrelation function in low wind speed conditions

    NASA Astrophysics Data System (ADS)

    Moor, L. P.; Degrazia, G. A.; Stefanello, M. B.; Mortarini, L.; Acevedo, O. C.; Maldaner, S.; Szinvelski, C. R. P.; Roberti, D. R.; Buligon, L.; Anfossi, D.

    2015-11-01

    In this study a new mathematical expression to describe the observed meandering autocorrelation functions in low-wind speed is proposed. The analysis utilizes a large number of best fit curves to show that the proposed theoretical function well reproduces the general form and the negative lobes characterizing the experimental meandering autocorrelation function. Further, the good agreement of the measured autocorrelation curves with the proposed algebraic autocorrelation function allows to calculate the magnitudes of the meandering period and of the loop parameter. The results agree with the values presented and discussed in the literature. Therefore, the new formulation describing experimental meandering autocorrelation functions can be used to simulate the dispersion of contaminant during low wind episodes and to determine relevant meandering parameters.

  15. Spatial autocorrelation of cancer incidence in Saudi Arabia.

    PubMed

    Al-Ahmadi, Khalid; Al-Zahrani, Ali

    2013-12-16

    Little is known about the geographic distribution of common cancers in Saudi Arabia. We explored the spatial incidence patterns of common cancers in Saudi Arabia using spatial autocorrelation analyses, employing the global Moran's I and Anselin's local Moran's I statistics to detect nonrandom incidence patterns. Global ordinary least squares (OLS) regression and local geographically-weighted regression (GWR) were applied to examine the spatial correlation of cancer incidences at the city level. Population-based records of cancers diagnosed between 1998 and 2004 were used. Male lung cancer and female breast cancer exhibited positive statistically significant global Moran's I index values, indicating a tendency toward clustering. The Anselin's local Moran's I analyses revealed small significant clusters of lung cancer, prostate cancer and Hodgkin's disease among males in the Eastern region and significant clusters of thyroid cancers in females in the Eastern and Riyadh regions. Additionally, both regression methods found significant associations among various cancers. For example, OLS and GWR revealed significant spatial associations among NHL, leukemia and Hodgkin's disease (r² = 0.49-0.67 using OLS and r² = 0.52-0.68 using GWR) and between breast and prostate cancer (r² = 0.53 OLS and 0.57 GWR) in Saudi Arabian cities. These findings may help to generate etiologic hypotheses of cancer causation and identify spatial anomalies in cancer incidence in Saudi Arabia. Our findings should stimulate further research on the possible causes underlying these clusters and associations.

  16. On the statistics of SuperDARN autocorrelation function estimates

    NASA Astrophysics Data System (ADS)

    Reimer, A. S.; Hussey, G. C.; Dueck, S. R.

    2016-06-01

    Time domain signal processing techniques are employed by the Super Dual Auroral Radar Network (SuperDARN) to obtain bulk measurements of the velocity and spectral width of F region ionospheric plasma irregularities. The measurements are obtained by fitting estimates of the mean autocorrelation function (ACF) of the radar target. To accurately and consistently extract target parameters from the mean unnormalized ACF, it is necessary to utilize error-weighted fitting algorithms with a weight given by the variance of the ACF. Currently implemented weights are ad hoc, and a detailed description of the statistical characterization of SuperDARN ACFs is needed. Following the discussions in Farley (1969) and Woodman and Hagfors (1969), which describe the variance for the mean normalized ACF used with incoherent scatter radars, we present analytic expressions for obtaining the variance of the real and imaginary components of the mean unnormalized SuperDARN ACF. These expressions are based on models by André et al. (1999) and Moorcroft (2004) of the voltage signal received by SuperDARN radars but may be used for other soft target radar systems. An algorithm for obtaining the variance of both the magnitude and phase of the mean ACF is also presented. The results of this study may be directly integrated into existing SuperDARN data analysis software and other pulse-Doppler radar systems that utilize estimates of the mean unnormalized ACF.

  17. Palm Tree Detection Using Circular Autocorrelation of Polar Shape Matrix

    NASA Astrophysics Data System (ADS)

    Manandhar, A.; Hoegner, L.; Stilla, U.

    2016-06-01

    Palm trees play an important role as they are widely used in a variety of products including oil and bio-fuel. Increasing demand and growing cultivation have created a necessity in planned farming and the monitoring different aspects like inventory keeping, health, size etc. The large cultivation regions of palm trees motivate the use of remote sensing to produce such data. This study proposes an object detection methodology on the aerial images, using shape feature for detecting and counting palm trees, which can support an inventory. The study uses circular autocorrelation of the polar shape matrix representation of an image, as the shape feature, and the linear support vector machine to standardize and reduce dimensions of the feature. Finally, the study uses local maximum detection algorithm on the spatial distribution of standardized feature to detect palm trees. The method was applied to 8 images chosen from different tough scenarios and it performed on average with an accuracy of 84% and 76.1%, despite being subjected to different challenging conditions in the chosen test images.

  18. Revisiting GRACE Antarctic ice mass trends and accelerations considering autocorrelation

    NASA Astrophysics Data System (ADS)

    Williams, Simon D. P.; Moore, Philip; King, Matt A.; Whitehouse, Pippa L.

    2014-01-01

    Previous GRACE-derived ice mass trends and accelerations have almost entirely been based on an assumption that the residuals to a regression model (including also semi-annual, annual and tidal aliasing terms) are not serially correlated. We consider ice mass change time series for Antarctica and show that significant autocorrelation is, in fact, present. We examine power-law and autoregressive models and compare them to those that assume white (uncorrelated) noise. The data do not let us separate autoregressive and power-law models but both indicate that white noise uncertainties need to be scaled up by a factor of up to 4 for accelerations and 6 for linear rates, depending on length of observations and location. For the whole of Antarctica, East Antarctica and West Antarctica the scale factors are 1.5, 1.5 and 2.2 respectively for the trends and, for the accelerations, 1.5, 1.5 and 2.1. Substantially lower scale-factors are required for offshore time series, suggesting much of the time-correlation is related to continental mass changes. Despite the higher uncertainties, we find significant (2-sigma) accelerations over much of West Antarctica (overall increasing mass loss) and Dronning Maud Land (increasing mass gain) as well as a marginally significant acceleration for the ice sheet as a whole (increasing mass loss).

  19. Exploring spatial autocorrelation of traffic crashes based on severity.

    PubMed

    Soltani, Ali; Askari, Sajad

    2017-01-19

    As a developing country, Iran has one of the highest crash-related deaths, with a typical rate of 15.6 cases in every 100 thousand people. This paper is aimed to find the potential temporal and spatial patterns of road crashes aggregated at traffic analysis zonal (TAZ) level in urban environments. Localization pattern and hotspot distribution were examined using geo-information approach to find out the impact of spatial/temporal dimensions on the emergence of such patterns. The spatial clustering of crashes and hotspots were assessed using spatial autocorrelation methods such as the Moran's I and Getis-Ord Gi* index. Comap was used for comparing clusters in three attributes: the time of occurrence, severity, and location. The analysis of the annually crash frequencies aggregated in 156 TAZ in Shiraz; from 2010 to 2014, Iran showed that both Moran's I method and Getis-Ord Gi* statistics produced significant clustering of crash patterns. While crashes emerged a clustered pattern, comparison of the spatio-temporal separations showed an accidental spread in distinct categories. The local governmental agencies can use the outcomes to adopt more effective strategies for traffic safety planning and management.

  20. RETURN TO DIVISION IA FOOTBALL FOLLOWING A 1ST METATARSOPHALANGEAL JOINT DORSAL DISLOCATION

    PubMed Central

    Cook, Chad; Zarzour, Hap; Moorman, Claude T.

    2010-01-01

    Background. Although rare in occurrence, a dorsal dislocation of the 1st metatarsophalangeal (MTP) joint has been successfully treated using surgical and/or non-operative treatment. No descriptions of conservative intervention following a dorsal dislocation of the MTP joint in an athlete participating in a high contact sport are present in the literature. Objectives. The purpose of this case report is to describe the intervention and clinical reasoning during the rehabilitative process of a collegiate football player diagnosed with a 1st MTP joint dorsal dislocation. The plan of care and return to play criteria used for this athlete are presented. Case Description. The case involved a 19-year-old male Division IA football player, who suffered a traumatic dorsal dislocation of the 1st MTP joint during practice. The dislocation was initially treated on-site by closed reduction. Non-operative management included immobilization, therapeutic exercises, non-steroidal anti-inflammatories, manual treatment, modalities, prophylactic athletic taping, gait training, and a sport specific progression program for full return to Division IA football. Outcomes. Discharge from physical therapy occurred after six weeks of treatment. At discharge, no significant deviations existed during running, burst, and agility related drills. At a six-month follow-up, the patient reported full return to all football activities including contact drills without restrictions. Discussion. This case describes an effective six-week rehabilitation intervention for a collegiate football player who sustained a traumatic great toe dorsal dislocation. Further study is suggested to evaluate the intervention strategies and timeframe for return to contact sports. PMID:21589669

  1. Design and construction of a femtosecond pulse autocorrelator using two-photon absorption in a luminescent diode

    NASA Astrophysics Data System (ADS)

    Arthur, M. A. G.; Rojo, R. R.; Jamasbi, N.; Mohebi, M.

    2003-06-01

    In this work, we present the design and construction of a femtosecond laser pulse autocorrelator, based on the two-photon absorption process in a light emitting diode (LED). Compared with traditional autocorrelators based on nonlinear crystals, this autocorrelator has the advantages of lower cost and greater ease of alignment. The intensity and interferometric autocorrelation traces obtained with this device for a titanium-sapphire laser with pulses that are less than 100 fs long, are also presented.

  2. Case study: a case of debilitating gout in the 1st metatarsophalangeal joint.

    PubMed

    Tanner, Natalie; Diaper, Ross; King, Mathew; Metcalfe, Stuart A

    2015-03-01

    Gout is a painful arthritic condition that affects many people worldwide. The disease has been associated with hyperuricaemia and life style risk factors such as obesity, alcohol intake, meat and seafood consumption. We present a case of a 67-year-old male with a history of gout, who attended the clinic with a painful 1st metatarsophalangeal joint, which had progressively worsened in pain, mobility and deformity in the last 20 years. Although lifestyle changes had been advised by the GP some years earlier such as a low purine based diet, management had only consisted of NSAID's, which had not significantly improved symptoms. Surgical excision of chalky white material from around the 1st metatarsophalangeal joint rendered the patient symptom free with increased mobility after 6 weeks. Histopathology confirmed the excised tissue as gouty tophus. Following this, the patient was placed on allopurinol, a xanthine oxidase inhibitor to prevent recurrent attacks. This case study highlights the importance of early recognition and prophylactic management in gout sufferers. In joints where the disease process is well-established surgical excision of the gouty tophus may help mitigate further disease progression, and restore quality of life to individuals.

  3. Patterns of spatial autocorrelation in stream water chemistry.

    PubMed

    Peterson, Erin E; Merton, Andrew A; Theobald, David M; Urquhart, N Scott

    2006-10-01

    Geostatistical models are typically based on symmetric straight-line distance, which fails to represent the spatial configuration, connectivity, directionality, and relative position of sites in a stream network. Freshwater ecologists have explored spatial patterns in stream networks using hydrologic distance measures and new geostatistical methodologies have recently been developed that enable directional hydrologic distance measures to be considered. The purpose of this study was to quantify patterns of spatial correlation in stream water chemistry using three distance measures: straight-line distance, symmetric hydrologic distance, and weighted asymmetric hydrologic distance. We used a dataset collected in Maryland, USA to develop both general linear models and geostatistical models (based on the three distance measures) for acid neutralizing capacity, conductivity, pH, nitrate, sulfate, temperature, dissolved oxygen, and dissolved organic carbon. The spatial AICC methodology allowed us to fit the autocorrelation and covariate parameters simultaneously and to select the model with the most support in the data. We used the universal kriging algorithm to generate geostatistical model predictions. We found that spatial correlation exists in stream chemistry data at a relatively coarse scale and that geostatistical models consistently improved the accuracy of model predictions. More than one distance measure performed well for most chemical response variables, but straight-line distance appears to be the most suitable distance measure for regional geostatistical modeling. It may be necessary to develop new survey designs that more fully capture spatial correlation at a variety of scales to improve the use of weighted asymmetric hydrologic distance measures in regional geostatistical models.

  4. Spatial Autocorrelation of Cancer Incidence in Saudi Arabia

    PubMed Central

    Al-Ahmadi, Khalid; Al-Zahrani, Ali

    2013-01-01

    Little is known about the geographic distribution of common cancers in Saudi Arabia. We explored the spatial incidence patterns of common cancers in Saudi Arabia using spatial autocorrelation analyses, employing the global Moran’s I and Anselin’s local Moran’s I statistics to detect nonrandom incidence patterns. Global ordinary least squares (OLS) regression and local geographically-weighted regression (GWR) were applied to examine the spatial correlation of cancer incidences at the city level. Population-based records of cancers diagnosed between 1998 and 2004 were used. Male lung cancer and female breast cancer exhibited positive statistically significant global Moran’s I index values, indicating a tendency toward clustering. The Anselin’s local Moran’s I analyses revealed small significant clusters of lung cancer, prostate cancer and Hodgkin’s disease among males in the Eastern region and significant clusters of thyroid cancers in females in the Eastern and Riyadh regions. Additionally, both regression methods found significant associations among various cancers. For example, OLS and GWR revealed significant spatial associations among NHL, leukemia and Hodgkin’s disease (r² = 0.49–0.67 using OLS and r² = 0.52–0.68 using GWR) and between breast and prostate cancer (r² = 0.53 OLS and 0.57 GWR) in Saudi Arabian cities. These findings may help to generate etiologic hypotheses of cancer causation and identify spatial anomalies in cancer incidence in Saudi Arabia. Our findings should stimulate further research on the possible causes underlying these clusters and associations. PMID:24351742

  5. Analytical and Numerical Characterization of Autocorrelation and Perturbation-Correlation Moving-Window Methods.

    PubMed

    Lee, Young Jong

    2017-01-01

    Moving-window (MW) approaches to two-dimensional correlation spectroscopy (2D-COS) make it possible to characterize spectral changes occurring in a narrow range of perturbation variable (e.g., time, temperature, and concentration). Despite the wide range of application, the physical meanings of MW correlation intensities have been only qualitatively associated with the direction and curvature of spectral intensity change with regard to a perturbation variable. Here are full and simplified analytical expressions of autocorrelation moving-window (ACMW) and synchronous and asynchronous perturbation-correlation moving-window ( s-PCMW and as-PCMW) intensities. When the window is set sufficiently narrower than the bandwidth of spectral change, the square root of ACMW intensity and s-PCMW intensity becomes proportional to the first order derivative, and as-PCMW intensity becomes proportional to the negative of the second order derivative. This paper demonstrates that both ACMW and PCMW profiles can be significantly altered by non-uniform perturbation spacing. It is also found that intensity noise can cause ACMW to display a false offset drift. This analytical and numerical characterization of the two MW correlation intensities elucidates their physical meanings and ascertains the analysis conditions for reliable interpretation.

  6. Effects of autocorrelation upon LANDSAT classification accuracy. [Richmond, Virginia and Denver, Colorado

    NASA Technical Reports Server (NTRS)

    Craig, R. G. (Principal Investigator)

    1983-01-01

    Richmond, Virginia and Denver, Colorado were study sites in an effort to determine the effect of autocorrelation on the accuracy of a parallelopiped classifier of LANDSAT digital data. The autocorrelation was assumed to decay to insignificant levels when sampled at distances of at least ten pixels. Spectral themes developed using blocks of adjacent pixels, and using groups of pixels spaced at least 10 pixels apart were used. Effects of geometric distortions were minimized by using only pixels from the interiors of land cover sections. Accuracy was evaluated for three classes; agriculture, residential and "all other"; both type 1 and type 2 errors were evaluated by means of overall classification accuracy. All classes give comparable results. Accuracy is approximately the same in both techniques; however, the variance in accuracy is significantly higher using the themes developed from autocorrelated data. The vectors of mean spectral response were nearly identical regardless of sampling method used. The estimated variances were much larger when using autocorrelated pixels.

  7. A broadly tunable autocorrelator for ultra-short, ultra-high power infrared optical pulses

    SciTech Connect

    Szarmes, E.B.; Madey, J.M.J.

    1995-12-31

    We describe the design of a crossed-beam, optical autocorrelator that uses an uncoated, birefringent beamsplitter to split a linearly polarized incident pulse into two orthogonally polarized pulses, and a Type II, SHG crystal to generate the intensity autocorrelation function. The uncoated beamsplitter accommodates extremely broad tunability while precluding any temporal distortion of ultrashort optical pulses at the dielectric interface, and the specific design provides efficient operation between 1 {mu}m and 4 {mu}m. Furthermore, the use of Type II SHG completely eliminates any single-beam doubling, so the autocorrelator can be operated at very shallow crossed-beam angles without generating a background pedestal. The autocorrelator has been constructed and installed in the Mark III laboratory at Duke University as a broadband diagnostic for ongoing compression experiments on the chirped-pulse FEL.

  8. Rapid and stable measurement of respiratory rate from Doppler radar signals using time domain autocorrelation model.

    PubMed

    Sun, Guanghao; Matsui, Takemi

    2015-01-01

    Noncontact measurement of respiratory rate using Doppler radar will play a vital role in future clinical practice. Doppler radar remotely monitors the tiny chest wall movements induced by respiration activity. The most competitive advantage of this technique is to allow users fully unconstrained with no biological electrode attachments. However, the Doppler radar, unlike other contact-type sensors, is easily affected by the random body movements. In this paper, we proposed a time domain autocorrelation model to process the radar signals for rapid and stable estimation of the respiratory rate. We tested the autocorrelation model on 8 subjects in laboratory, and compared the respiratory rates detected by noncontact radar with reference contact-type respiratory effort belt. Autocorrelation model showed the effects of reducing the random body movement noise added to Doppler radar's respiration signals. Moreover, the respiratory rate can be rapidly calculated from the first main peak in the autocorrelation waveform within 10 s.

  9. Local slope, hillslope length and upslope unstable area as 1st order controls on co-seismic landslide hazard.

    NASA Astrophysics Data System (ADS)

    Milledge, D.; Densmore, A. L.; Petley, D. N.; Bellugi, D. G.; Li, G.

    2015-12-01

    Many communities in mountainous areas have limited access to and/or understanding of co-seismic landslide hazard maps. Furthermore these maps rarely provide the information that a community seeks: Where is safest? How big could the landslide be? Geomorphic intuition suggests that: 1) on the ridges one is less likely to be hit by a landslide than elsewhere in the landscape; 2) hazard increases with the amount of upslope unstable area; 3) longer slopes contain more candidate landslides and are also capable of producing larger landslides thus they constitute a more severe hazard. These observations could help communities in siting infrastructure or making earthquake plans but have not, to our knowledge, been tested against past landslide inventories. Co-seismic landslide models make no attempt to predict landslide size and focus on initiation, ignoring the runout which is critical in the slope length control on hazard. Here we test our intuitive hypotheses using an inventory of co-seismic landslides from the 2008 Wenchuan earthquake. The inventory is mapped from high-resolution remote imagery using an automated algorithm and manual delineation and does not distinguish between source and runout zones. Discretizing the study area into 30 m cells we define landslide hazard as the probability that a cell is within a mapped landslide polygon (p(ls)). We find that p(ls) increases rapidly with increasing slope and upslope area. Locations with low local slope (<10˚) or upslope area (<900 m2/m) have p(ls) less than one third of the areal average. The joint p(ls) conditional on local slope and upslope area identifies long steep slopes as particularly hazardous and ridges (where slope and upslope area are both low) as particularly low hazard. Examining the slope lengths associated with each landslide in the inventory we find that hillslope length sets an upper limit on landslide size but that its influence on the detailed size distribution is more difficult to untangle. Finally, we combine local slope and upslope unstable area in a simple mechanistic rule-based model of landslide runout hazard and test its ability to predict p(ls). Our findings support the intuitive view that long steep slopes are among the most hazardous locations while ridges are the least hazardous locations in terms of co-seismic landslides.

  10. Effect of unequal rise and fall times on the autocorrelation function of a PN sequence

    NASA Astrophysics Data System (ADS)

    Churchill, F. E.

    1990-10-01

    The rise and fall times of a pseudo-noise (PN) waveform are of concern in a short-range, CW radar such as a missile fuze radar. An inequality creates a spurious pair of sidelobes and a spiky ripple on the sidelobes of the autocorrelation function, which may cause false alarms in the radar. Analytical expressions are presented which relate the spurious responses of the autocorrelation function to the waveform rise and fall times.

  11. Orthogonal Higher Order Structure of the Wechsler Intelligence Scale for Children--Fourth Edition

    ERIC Educational Resources Information Center

    Watkins, Marley W.

    2006-01-01

    According to J. B. Carroll's (1993) 3-stratum theory, performance on any subtest reflects a mixture of both 2nd-order and 1st-order factors. To disentangle these influences, variance explained by the general factor should be extracted first. The 1st-order factors are then residualized, leaving them orthogonal to the general factor and each other.…

  12. Temporal autocorrelation in host density increases establishment success of parasitoids in an experimental system

    PubMed Central

    Vercken, Elodie; Fauvergue, Xavier; Ris, Nicolas; Crochard, Didier; Mailleret, Ludovic

    2015-01-01

    Environmental variation is classically expected to affect negatively population growth and to increase extinction risk, and it has been identified as a major determinant of establishment failures in the field. Yet, recent theoretical investigations have shown that the structure of environmental variation and more precisely the presence of positive temporal autocorrelation might alter this prediction. This is particularly likely to affect the establishment dynamics of biological control agents in the field, as host–parasitoid interactions are expected to induce temporal autocorrelation in host abundance. In the case where parasitoid populations display overcompensatory dynamics, the presence of such positive temporal autocorrelation should increase their establishment success in a variable environment. We tested this prediction in laboratory microcosms by introducing parasitoids to hosts whose abundances were manipulated to simulate uncorrelated or positively autocorrelated variations in carrying capacity. We found that environmental variability decreased population size and increased parasitoid population variance, which is classically expected to extinction risk. However, although exposed to significant environmental variation, we found that parasitoid populations experiencing positive temporal autocorrelation in host abundance were more likely to persist than populations exposed to uncorrelated variation. These results confirm that environmental variation is a key determinant of extinction dynamics that can have counterintuitive effects depending on its autocorrelation structure. PMID:26257880

  13. Diffuse correlation spectroscopy with a fast Fourier transform-based software autocorrelator

    NASA Astrophysics Data System (ADS)

    Dong, Jing; Bi, Renzhe; Ho, Jun Hui; Thong, Patricia S. P.; Soo, Khee-Chee; Lee, Kijoon

    2012-09-01

    Diffuse correlation spectroscopy (DCS) is an emerging noninvasive technique that probes the deep tissue blood flow, by using the time-averaged intensity autocorrelation function of the fluctuating diffuse reflectance signal. We present a fast Fourier transform (FFT)-based software autocorrelator that utilizes the graphical programming language LabVIEW (National Instruments) to complete data acquisition, recording, and processing tasks. The validation and evaluation experiments were conducted on an in-house flow phantom, human forearm, and photodynamic therapy (PDT) on mouse tumors under the acquisition rate of ˜400 kHz. The software autocorrelator in general has certain advantages, such as flexibility in raw photon count data preprocessing and low cost. In addition to that, our FFT-based software autocorrelator offers smoother starting and ending plateaus when compared to a hardware correlator, which could directly benefit the fitting results without too much sacrifice in speed. We show that the blood flow index (BFI) obtained by using a software autocorrelator exhibits better linear behavior in a phantom control experiment when compared to a hardware one. The results indicate that an FFT-based software autocorrelator can be an alternative solution to the conventional hardware ones in DCS systems with considerable benefits.

  14. 4th generation of the 1st level surface detector trigger in the Pierre Auger Observator

    NASA Astrophysics Data System (ADS)

    Szadkowski, Z.

    The proposal of a new 4th generation of the Front-End with the advanced 1st level triggers for the Infill Array of the Pierre Auger Observatory and for the Auger North is described. Newest FPGA chips offer much higher capacity of logic registers and memories, as well as DSP blocks. The calibration channel, previously supported by an external dual-port RAM, has been fully implemented into FPGA chip, through a large internal memory. In turn DSP blocks allowed on implementation of much more sophisticated spectral trigger algorithms. A single chip simplified board design, newer architecture of FPGA reduced resouces utilization and power consumption. Higher sampling in the new Front- End in comparison with previous 40 MHz designs as well as free resources for new detection algotithms can be a good platform for CR radio detection technique at Auger enhancing a duty cycle for the detection of UHECR’s.

  15. Meeting report for the 1st skin microbiota workshop, boulder, CO October 15-16 2012

    PubMed Central

    2014-01-01

    This report details the outcome of the 1st Skin Microbiota Workshop, Boulder, CO, held on October 15th-16th 2012. The workshop was arranged to bring Department of Defense personnel together with experts in microbial ecology, human skin physiology and anatomy, and computational techniques for interrogating the microbiome to define research frontiers at the intersection of these important areas. The workshop outlined a series of questions and created several working groups to address those questions, specifically to promote interdisciplinary activity and potential future collaboration. The US Army provided generous grant support and the meeting was organized and hosted by the University of Colorado at Boulder. A primary forward vision of the meeting was the importance of understanding skin microbial communities to improve the health and stealth of US Army warfighters.

  16. Summary of the 1st International Workshop on Environmental, Safety and Economic Aspects of Fusion Power

    NASA Astrophysics Data System (ADS)

    Wu, Y.; Stevens, E.; Kim, K.; Maisonnier, D.; Kalashnikov, A.; Tobita, K.; Jackson, D.; Alejaldre, C.; Perrault, D.; Panayotov, D.; Merrill, B.; Grisolia, C.; Zucchetti, M.; Pinna, T.; van Houtte, D.; Konishi, S.; Kolbasov, B.

    2016-12-01

    The 1st International workshop on Environmental, Safety and Economic Aspects of Fusion Power (ESEFP) was held on 13 September 2015 at Jeju Island, South Korea. The workshop was initiated by the International Energy Agency Implementing Agreement on a Co-operative Program on ESEFP. The workshop was well attended with about forty participants representing twelve institutions in ten countries. The presentations covered safety issues and environmental impacts, availability improvement and risk control and socio-economic aspects of fusion power. Safety and licensing gaps between DEMO and ITER were discussed in depth with the consensus output presented as a plenary presentation at the 12th International Symposium on Fusion Nuclear Technology (ISFNT-12). The next workshop is planned to be held in conjunction with the ISFNT-13 in 2017.

  17. An investigation on thermal patterns in Iran based on spatial autocorrelation

    NASA Astrophysics Data System (ADS)

    Fallah Ghalhari, Gholamabbas; Dadashi Roudbari, Abbasali

    2016-12-01

    The present study aimed at investigating temporal-spatial patterns and monthly patterns of temperature in Iran using new spatial statistical methods such as cluster and outlier analysis, and hotspot analysis. To do so, climatic parameters, monthly average temperature of 122 synoptic stations, were assessed. Statistical analysis showed that January with 120.75% had the most fluctuation among the studied months. Global Moran's Index revealed that yearly changes of temperature in Iran followed a strong spatially clustered pattern. Findings showed that the biggest thermal cluster pattern in Iran, 0.975388, occurred in May. Cluster and outlier analyses showed that thermal homogeneity in Iran decreases in cold months, while it increases in warm months. This is due to the radiation angle and synoptic systems which strongly influence thermal order in Iran. The elevations, however, have the most notable part proved by Geographically weighted regression model. Iran's thermal analysis through hotspot showed that hot thermal patterns (very hot, hot, and semi-hot) were dominant in the South, covering an area of 33.5% (about 552,145.3 km2). Regions such as mountain foot and low lands lack any significant spatial autocorrelation, 25.2% covering about 415,345.1 km2. The last is the cold thermal area (very cold, cold, and semi-cold) with about 25.2% covering about 552,145.3 km2 of the whole area of Iran.

  18. Detecting Anomaly Regions in Satellite Image Time Series Based on Sesaonal Autocorrelation Analysis

    NASA Astrophysics Data System (ADS)

    Zhou, Z.-G.; Tang, P.; Zhou, M.

    2016-06-01

    Anomaly regions in satellite images can reflect unexpected changes of land cover caused by flood, fire, landslide, etc. Detecting anomaly regions in satellite image time series is important for studying the dynamic processes of land cover changes as well as for disaster monitoring. Although several methods have been developed to detect land cover changes using satellite image time series, they are generally designed for detecting inter-annual or abrupt land cover changes, but are not focusing on detecting spatial-temporal changes in continuous images. In order to identify spatial-temporal dynamic processes of unexpected changes of land cover, this study proposes a method for detecting anomaly regions in each image of satellite image time series based on seasonal autocorrelation analysis. The method was validated with a case study to detect spatial-temporal processes of a severe flooding using Terra/MODIS image time series. Experiments demonstrated the advantages of the method that (1) it can effectively detect anomaly regions in each of satellite image time series, showing spatial-temporal varying process of anomaly regions, (2) it is flexible to meet some requirement (e.g., z-value or significance level) of detection accuracies with overall accuracy being up to 89% and precision above than 90%, and (3) it does not need time series smoothing and can detect anomaly regions in noisy satellite images with a high reliability.

  19. Global Autocorrelation Scales of the Partial Pressure of Oceanic CO2

    NASA Technical Reports Server (NTRS)

    Li, Zhen; Adamec, David; Takahashi, Taro; Sutherland, Stewart C.

    2004-01-01

    A global database of approximately 1.7 million observations of the partial pressure of carbon dioxide in surface ocean waters (pCO2) collected between 1970 and 2003 is used to estimate its spatial autocorrelation structure. The patterns of the lag distance where the autocorrelation exceeds 0.8 is similar to patterns in the spatial distribution of the first baroclinic Rossby radius of deformation indicating that ocean circulation processes play a significant role in determining the spatial variability of pCO2. For example, the global maximum of the distance at which autocorrelations exceed 0.8 averages about 140 km in the equatorial Pacific. Also, the lag distance at which the autocorrelation exceed 0.8 is greater in the vicinity of the Gulf Stream than it is near the Kuroshio, approximately 50 km near the Gulf Stream as opposed to 20 km near the Kuroshio. Separate calculations for times when the sun is north and south of the equator revealed no obvious seasonal dependence of the spatial autocorrelation scales. The pCO2 measurements at Ocean Weather Station (OWS) 'P', in the eastern subarctic Pacific (50 N, 145 W) is the only fixed location where an uninterrupted time series of sufficient length exists to calculate a meaningful temporal autocorrelation function for lags greater than a few days. The estimated temporal autocorrelation function at OWS 'P', is highly variable. A spectral analysis of the longest four pCO2 time series indicates a high level of variability occurring over periods from the atmospheric synoptic to the maximum length of the time series, in this case 42 days. It is likely that a relative peak in variability with a period of 3-6 days is related to atmospheric synoptic period variability and ocean mixing events due to wind stirring. However, the short length of available time series makes identifying temporal relationships between pCO2 and atmospheric or ocean processes problematic.

  20. Wave packet autocorrelation functions for quantum hard-disk and hard-sphere billiards in the high-energy, diffraction regime.

    PubMed

    Goussev, Arseni; Dorfman, J R

    2006-07-01

    We consider the time evolution of a wave packet representing a quantum particle moving in a geometrically open billiard that consists of a number of fixed hard-disk or hard-sphere scatterers. Using the technique of multiple collision expansions we provide a first-principle analytical calculation of the time-dependent autocorrelation function for the wave packet in the high-energy diffraction regime, in which the particle's de Broglie wavelength, while being small compared to the size of the scatterers, is large enough to prevent the formation of geometric shadow over distances of the order of the particle's free flight path. The hard-disk or hard-sphere scattering system must be sufficiently dilute in order for this high-energy diffraction regime to be achievable. Apart from the overall exponential decay, the autocorrelation function exhibits a generally complicated sequence of relatively strong peaks corresponding to partial revivals of the wave packet. Both the exponential decay (or escape) rate and the revival peak structure are predominantly determined by the underlying classical dynamics. A relation between the escape rate, and the Lyapunov exponents and Kolmogorov-Sinai entropy of the counterpart classical system, previously known for hard-disk billiards, is strengthened by generalization to three spatial dimensions. The results of the quantum mechanical calculation of the time-dependent autocorrelation function agree with predictions of the semiclassical periodic orbit theory.

  1. PREFACE: 1st European Conference on Gas Micro Flows (GasMems 2012)

    NASA Astrophysics Data System (ADS)

    Frijns, Arjan; Valougeorgis, Dimitris; Colin, Stéphane; Baldas, Lucien

    2012-05-01

    The aim of the 1st European Conference on Gas Micro Flows is to advance research in Europe and worldwide in the field of gas micro flows as well as to improve global fundamental knowledge and to enable technological applications. Gas flows in microsystems are of great importance and touch almost every industrial field (e.g. fluidic microactuators for active control of aerodynamic flows, vacuum generators for extracting biological samples, mass flow and temperature micro-sensors, pressure gauges, micro heat-exchangers for the cooling of electronic components or for chemical applications, and micro gas analyzers or separators). The main characteristic of gas microflows is their rarefaction, which for device design often requires modelling and simulation both by continuous and molecular approaches. In such flows various non-equilibrium transport phenomena appear, while the role played by the interaction between the gas and the solid device surfaces becomes essential. The proposed models of boundary conditions often need an empirical adjustment strongly dependent on the micro manufacturing technique. The 1st European Conference on Gas Micro Flows is organized under the umbrella of the recently established GASMEMS network (www.gasmems.eu/) consisting of 13 participants and six associate members. The main objectives of the network are to structure research and train researchers in the fields of micro gas dynamics, measurement techniques for gaseous flows in micro experimental setups, microstructure design and micro manufacturing with applications in lab and industry. The conference takes place on June 6-8 2012, at the Skiathos Palace Hotel, on the beautiful island of Skiathos, Greece. The conference has received funding from the European Community's Seventh Framework Programme FP7/2007-2013 under grant agreement ITN GASMEMS no. 215504. It owes its success to many people. We would like to acknowledge the support of all members of the Scientific Committee and of all

  2. PREFACE: 1st International Conference on Rheology and Modeling of Materials

    NASA Astrophysics Data System (ADS)

    Gömze, László A.

    2015-04-01

    Understanding the rheological properties of materials and their rheological behaviors during their manufacturing processes and in their applications in many cases can help to increase the efficiency and competitiveness not only of the finished goods and products but the organizations and societies also. The more scientific supported and prepared organizations develop more competitive products with better thermal, mechanical, physical, chemical and biological properties and the leading companies apply more competitive knowledge, materials, equipment and technology processes. The idea to organize in Hungary the 1st International Conference on Rheology and Modeling of Materials we have received from prospective scientists, physicists, chemists, mathematicians and engineers from Asia, Europe, North and South America including India, Korea, Russia, Turkey, Estonia, France, Italy, United Kingdom, Chile, Mexico and USA. The goals of ic-rmm1 the 1st International Conference on Rheology and Modeling of Materials are the following: • Promote new methods and results of scientific research in the fields of modeling and measurements of rheological properties and behavior of materials under processing and applications. • Change information between the theoretical and applied sciences as well as technical and technological implantations. • Promote the communication between the scientists of different disciplines, nations, countries and continents. The international conference ic-rmm1 provides a platform among the leading international scientists, researchers, PhD students and engineers for discussing recent achievements in measurement, modeling and application of rheology in materials technology and materials science of liquids, melts, solids, crystals and amorphous structures. Among the major fields of interest are the influences of material structures, mechanical stresses temperature and deformation speeds on rheological and physical properties, phase transformation of

  3. 1st Advanced Marine Renewable Energy Instrumentation Experts Workshop: April 5-7, 2011

    SciTech Connect

    Not Available

    2011-10-01

    The U.S. marine energy industry is actively pursuing development of offshore wind and marine hydrokinetic (MHK) energy systems. Experience in the wind energy sector demonstrates that new technology development requires thorough measurement and characterization of the environmental conditions prevalent at installation sites and of technology operating in the field. Presently, there are no turn-key instrumentation system solutions that meet the measurement needs of the marine energy industry. The 1st Advanced Marine Renewable Energy Instrumentation Experts Workshop brought together technical experts from government laboratories, academia, and industry representatives from marine energy, wind, offshore oil and gas, and instrumentation developers to present and discuss the instrumentation needs of the marine energy industry. The goals of the meeting were to: (1) Share the latest relevant knowledge among technical experts; (2) Review relevant state-of-the-art field measurement technologies and methods; (3) Review lessons learned from recent field deployments; (4) Identify synergies across different industries; (5) Identify gaps between existing and needed instrumentation capabilities; (6) Understand who are the leading experts; (7) Provide a forum where stakeholders from the marine energy industry could provide substantive input in the development of new marine energy field deployable instrumentation packages.

  4. The Current Status of the 1st Electromagnetism Satellite Mission in China

    NASA Astrophysics Data System (ADS)

    Shen, Xuhui; Wang, Lanwei; Zhang, Xuemin; Yuan, Shigeng

    2014-05-01

    The 1st China Electromagnetism Satellite now is on its Phase C for Electrical Mode and Qualification mode. And according to the developing schedule, the satellite is due to be launched before the end of 2016. The first electromagnetism satellite is defined as an experiment satellite with it's major scientific objectives to monitor the global electromagnetic fields as well as plasma distribution in ionosphere, to provide seismo-eletromagnetic information for studying earthquake mechanism and short-term prediction of large earthquakes, and to share the data with earthquake sciences and space sciences. The satellite will work on Sun synchronous orbit with the attitude of about 500km and descending node 14:00LT. The payload assembly are as following: Search Coil Magnetometer, Electric Field Detector, Flux-Gate Magnetometer, Plasma Analyser, Langmuir Probe, GNSS Two-frequency Receiver, Three-frequency Transmitter, Energetic Particle Detector. The main physical parameters and products of the mission are electromagnetic field and electromagnetic wave, plasma density, temperature, and tomography in ionosphere, high energy particle disturbance, etc. The Chinese work team is ready to open the data and jointly research on common topics with international colleagues.

  5. 1st ACT global trajectory optimisation competition: Results found at the Jet Propulsion Laboratory

    NASA Astrophysics Data System (ADS)

    Petropoulos, Anastassios E.; Kowalkowski, Theresa D.; Vavrina, Matthew A.; Parcher, Daniel W.; Finlayson, Paul A.; Whiffen, Gregory J.; Sims, Jon A.

    2007-11-01

    Results obtained at the Jet Propulsion Laboratory for the 1st ACT global trajectory optimisation competition are presented and the methods used to obtain them are described. The search for the globally optimal, low-thrust, gravity-assist trajectory for maximally deflecting an asteroid is performed in two steps. The first step involves a rough global search of the global search space, which has, however, been somewhat bounded based on prior mission-design experience, intuition, and energy arguments. A shape-based method is used to represent the low-thrust arcs, while the ballistic portions are searched almost exhaustively. The second step involves local optimisation of trajectories which stand out from the rough global search. The low-thrust optimisation problem is turned into a parameter optimisation problem by approximating the continuous thrusting as a series of impulsive manoeuvres. Of the many trajectories found, three optimal trajectories are reported and compared, including the one submitted for the competition. The best one employed a double-Venus, quadruple-Earth, Jupiter Saturn Jupiter gravity-assist sequence. The trajectory submitted for the competition used one less Venus flyby and one less Earth flyby.

  6. Calibration and commutability assessment of the 1st International Standard for Diphtheria Antitoxin Human.

    PubMed

    Stickings, Paul; Rigsby, Peter; Coombes, Laura; von Hunolstein, Christina; Ralli, Luisa; Pinto, Antonella; Sesardic, Dorothea

    2013-11-01

    The 1st International Standard for Diphtheria Antitoxin Human (coded 10/262) was established by the World Health Organization Expert Committee on Biological Standardization in 2012. This paper describes the production, characterization and calibration of the new standard which is intended for use in the standardization of assays used to measure diphtheria antibody responses in human serum. The new standard was calibrated in terms of the International Standard for Diphtheria Antitoxin Equine in an international collaborative study. A total of 8 participants from 8 different countries performed in vivo and/or in vitro toxin neutralization tests and returned data that was used to assign units to the proposed new standard. The new standard has a diphtheria antitoxin potency of 2 IU/ampoule and is predicted to be stable. A follow up study was performed to assess commutability of the new standard. The follow up study was an existing external quality assessment, modified to include the new standard. Results obtained suggest that the new standard is commutable, showing comparable behaviour to native human serum samples in the majority of the assays compared, and is therefore suitable for use as a reference preparation in assays used to measure the level of anti-diphtheria antibodies in human serum.

  7. Wind-US Results for the AIAA 1st Propulsion Aerodynamics Workshop

    NASA Technical Reports Server (NTRS)

    Yoder, Dennis; Dippold, Vance, III; Georgiadis, Nicholas

    2012-01-01

    This presentation contains Wind-US results presented at the 1st Propulsion Aerodynamics Workshop. The The workshop was organized by the American Institute of Aeronautics and Astronautics, Air Breathing Propulsion Propulsion Systems Integration Technical Committee with the purpose of assessing the accuracy of computational computational fluid dynamics for air breathing propulsion applications. Attendees included representatives from representatives from government, industry, academia, and commercial software companies. Participants were were encouraged to explore and discuss all aspects of the simulation process including the effects of mesh type and mesh type and refinement, solver numerical schemes, and turbulence modeling. The first set of challenge cases involved computing the thrust and discharge coefficients for a series of convergent convergent nozzles for a range of nozzle pressure ratios between 1.4 and 7.0. These configurations included a included a reference axisymmetric nozzle as well as 15deg , 25deg , and 40deg conical nozzles. Participants were also asked also asked to examine the plume shock structure for two cases where the 25deg conical nozzle was bifurcated by a bifurcated by a solid plate. The final test case was a serpentine inlet diffuser with an outlet to inlet area ratio of 1.52 ratio of 1.52 and an offset of 1.34 times the inlet diameter. Boundary layer profiles, wall static pressure, and total and total pressure at downstream rake locations were examined.

  8. Providing simulation experiences for large cohorts of 1st year nursing students: evaluating quality and impact.

    PubMed

    Rochester, Suzanne; Kelly, Michelle; Disler, Rebecca; White, Haidee; Forber, Jan; Matiuk, Sonia

    2012-01-01

    To provide each student within a large cohort the opportunity to participate in a small group simulation that meets recognised quality indicators is a challenge for Bachelor of Nursing programmes in Australia. This paper, as part of a larger longitudinal study, describes one approach used to manage a simulation for 375 1st year nursing students and to report on the quality of the experience from the student's perspective. To ensure quality was maintained within the large cohort, aspects of the simulation were assessed against the following indicators: alignment with curriculum pedagogy and goals; preparation of students and staff; fidelity; and debriefing. Data obtained from a student focus group were analysed in the context of the quality indicators. The following themes emerged from the data: knowing what to expect; assuming roles for the simulation; authenticity and thinking on your feet; feeling the RN role; and, preparation for clinical practice. This paper demonstrates it is possible to provide students in large cohorts with active participatory roles in simulations whilst maintaining quality indicators.

  9. Parenting and Preschool Self-Regulation as Predictors of Social Emotional Competence in 1st Grade

    PubMed Central

    Russell, Beth S.; Lee, Jungeun Olivia; Spieker, Susan; Oxford, Monica L.

    2016-01-01

    The current longitudinal study used data from the National Institute of Child Health and Human Development (NICHD) Study of Early Child Care and Youth Development (SECCYD) to examine a model of development that emphasizes early caregiving environments as predictors of social emotional competence (including classroom competence). This path analysis model included features of parenting, emotion regulation, preschool language skills, and attention to predict child outcomes in 1st grade. Early caregiving environments were directly predictive of peer relationship satisfaction, oppositional behavior, social skills, and classroom competence over and above significant mediated effects through preschool self regulation (language, inattention, and anger/frustration). These results suggest that the characteristics of supportive and stimulating caregiving shift in valence over time, such that qualities of the infant-child relationship that are significant in predicting early childhood outcomes are not the same as the caregiving qualities that move to the foreground in predicting primary school outcomes. Implications for school-readiness programming are discussed, including interventions in the early caregiving system to encourage sensitive and supportive parent child interactions to bolster school readiness via the development of social-emotional competence. PMID:27616805

  10. The relation between 1st grade grey matter volume and 2nd grade math competence.

    PubMed

    Price, Gavin R; Wilkey, Eric D; Yeo, Darren J; Cutting, Laurie E

    2016-01-01

    Mathematical and numerical competence is a critical foundation for individual success in modern society yet the neurobiological sources of individual differences in math competence are poorly understood. Neuroimaging research over the last decade suggests that neural mechanisms in the parietal lobe, particularly the intraparietal sulcus (IPS) are structurally aberrant in individuals with mathematical learning disabilities. However, whether those same brain regions underlie individual differences in math performance across the full range of math abilities is unknown. Furthermore, previous studies have been exclusively cross-sectional, making it unclear whether variations in the structure of the IPS are caused by or consequences of the development of math skills. The present study investigates the relation between grey matter volume across the whole brain and math competence longitudinally in a representative sample of 50 elementary school children. Results show that grey matter volume in the left IPS at the end of 1st grade relates to math competence a year later at the end of 2nd grade. Grey matter volume in this region did not change over that year, and was still correlated with math competence at the end of 2nd grade. These findings support the hypothesis that the IPS and its associated functions represent a critical foundation for the acquisition of mathematical competence.

  11. Establishing the 1st Chinese National Standard for inactivated hepatitis A vaccine.

    PubMed

    Gao, Fan; Mao, Qun-Ying; Wang, Yi-Ping; Chen, Pan; Liang, Zheng-Lun

    2016-07-01

    A reference standard calibrated in the International Units is needed for the quality control of hepatitis A vaccine. Thus, National Institutes for Food and Drug Control launched a project to establish a non-adsorbed inactivated hepatitis A vaccine reference as the working standard calibrated against the 1st International Standard (IS). Two national standard candidates (NSCs) were obtained from two manufacturers, and designated as NSC A (lyophilized form) and NSC B (liquid form). Six laboratories participated in the collaborative study and were asked to use their in-house validated enzyme-linked immunosorbent assay methods to detect hepatitis A vaccine antigen content. Although both exhibited good parallelism and linear relationship with IS, NSC B showed a better agreement among laboratories than NSC A. And based on suitability of the candidates, NSC B was selected. The accelerated degradation study showed that NSC B was stable at the storage temperature (≤-70 °C). Therefore NSC B was approved as the first Chinese national antigen standard for inactivated hepatitis A vaccine, with an assigned antigen content of 70 IU/ml.

  12. 1st paleomagnetic investigation of Nubia Sandstone at Kalabsha, south Western Desert of Egypt

    NASA Astrophysics Data System (ADS)

    Mostafa, R.; Khashaba, A.; El-Hemaly, I. A.; Takla, E. M.; Abdel Aal, E.; Odah, H.

    2016-06-01

    Two profiles have been sampled from the Nubia Sandstone at Aswan, south Western Desert: the 1st profile has been taken from Abu Aggag Formation and the 2nd one was from Sabaya Formation (23.25 °N, 32.75 °E). 136 oriented cores (from 9 sites) have been sampled. Abu Aggag Formation is of Late Cretaceous (Turonian) and Sabaya Formation is of early Cretaceous (Albian-Cenomanian). The studied rocks are subjected to rock magnetic measurements as well as demagnetization treatment. It has been found that hematite is the main magnetic mineral in both formations. Four profile sections from Abu Aggag Formation, yielded a magnetic component with D = 352.7°, I = 36.6° with α95 = 5.2° and the corresponding pole lies at Lat. = 82.8 °N and Long. = 283.1 °E. Five profile sections from Sabaya Formation, yielded a magnetic component with D = 348.6°, I = 33.3° with α95 = 5.8° and the corresponding pole lies at Lat. = 78.3 °N and Long. = 280.4 °E. The obtained paleopole for the two formations lies at Lat. = 80.5 °N and Long. = 281.7 °E. The obtaind magnetic components are considered primary and the corresponding paleopole reflects the age of Nubia Sandstone when compared with the previously obtained Cretaceous poles for Egypt.

  13. Spatial Autocorrelation Analysis of Chinese Inter-Provincial Industrial Chemical Oxygen Demand Discharge

    PubMed Central

    Zhao, Xiaofeng; Huang, Xianjin; Liu, Yibo

    2012-01-01

    A spatial autocorrelation analysis method is adopted to process the spatial dynamic change of industrial Chemical Oxygen Demand (COD) discharge in China over the past 15 years. Studies show that amount and intensity of industrial COD discharges are on a decrease, and the tendency is more remarkable for discharge intensity. There are large differences between inter-provincial discharge amount and intensity, and with different spatial differentiation features. Global spatial autocorrelation analysis reveals that Global Moran’s I of discharge amount and intensity is on the decrease. In space, there is an evolution from an agglomeration pattern to a discretization pattern. Local spatial autocorrelation analysis shows that the agglomeration area of industrial COD discharge amount and intensity varies greatly in space with time. Stringent environmental regulations and increased funding for environmental protections are the crucial factors to cut down industrial COD discharge amount and intensity. PMID:22829788

  14. Spectrum sensing algorithm based on autocorrelation energy in cognitive radio networks

    NASA Astrophysics Data System (ADS)

    Ren, Shengwei; Zhang, Li; Zhang, Shibing

    2016-10-01

    Cognitive radio networks have wide applications in the smart home, personal communications and other wireless communication. Spectrum sensing is the main challenge in cognitive radios. This paper proposes a new spectrum sensing algorithm which is based on the autocorrelation energy of signal received. By taking the autocorrelation energy of the received signal as the statistics of spectrum sensing, the effect of the channel noise on the detection performance is reduced. Simulation results show that the algorithm is effective and performs well in low signal-to-noise ratio. Compared with the maximum generalized eigenvalue detection (MGED) algorithm, function of covariance matrix based detection (FMD) algorithm and autocorrelation-based detection (AD) algorithm, the proposed algorithm has 2 11 dB advantage.

  15. Robust testing for normality of error terms with presence of autocorrelation and conditional heteroscedasticity

    NASA Astrophysics Data System (ADS)

    Střelec, Luboš; Stehlík, Milan

    2017-01-01

    Normality of the error terms in regression models is one of the basic assumptions in the applied regression analysis. Therefore, testing for normality of the error terms constitutes one of the most important steps of regression model verification and validation. Failure to assess non-normality of the error terms may lead to incorrect results of usual statistical inference techniques such as t-test or F-test. Within the applied regression analysis there is a frequent problem of the presence of autocorrelation and conditional heteroscedasticity of the error terms. Under both autocorrelation and heteroscedasticity, the usual OLS estimators are still unbiased, linear and asymptotically normally distributed, however, no longer have the minimum variance property among all linear unbiased estimators. Therefore, the aim of this paper is to present and discuss normality testing of the error terms with presence of autocorrelation and conditional heteroscedasticity. To explore the power of selected classical tests and robust tests for normality, we perform simulation study.

  16. Assessing the Significance of Global and Local Correlations under Spatial Autocorrelation; a Nonparametric Approach

    PubMed Central

    Mazumder, Rahul; McInturff, Alex; McCauley, Douglas J.; Hastie, Trevor

    2014-01-01

    Summary We propose a method to test the correlation of two random fields when they are both spatially auto-correlated. In this scenario, the assumption of independence for the pair of observations in the standard test does not hold, and as a result we reject in many cases where there is no effect (the precision of the null distribution is overestimated). Our method recovers the null distribution taking into account the autocorrelation. It uses Monte-Carlo methods, and focuses on permuting, and then smoothing and scaling one of the variables to destroy the correlation with the other, while maintaining at the same time the initial autocorrelation. With this simulation model, any test based on the independence of two (or more) random fields can be constructed. This research was motivated by a project in biodiversity and conservation in the Biology Department at Stanford University. PMID:24571609

  17. Maternal Sleep-Related Cognitions and Infant Sleep: A Longitudinal Study from Pregnancy through the 1st Year

    ERIC Educational Resources Information Center

    Tikotzky, Liat; Sadeh, Avi

    2009-01-01

    Infant sleep is a major source of concern for many parents. The aims of this longitudinal study were to assess: (a) the development of sleep patterns among infants, (b) the development of maternal cognitions regarding infant sleep, and (c) the relations between these domains during the 1st year of life. Eighty-five mothers were recruited during…

  18. Comparative analysis of 1st, 2nd, and 4th year MD students' attitudes toward Complementary Alternative Medicine (CAM)

    PubMed Central

    Riccard, Christopher P; Skelton, Michele

    2008-01-01

    Background To identify and report the attitudes and beliefs of 1st, 2nd, and 4th year medical students toward complementary alternative medicine (CAM). Methods The previously validated and reliability tested CHBQ was administered to medical students attending the University of South Florida School of Medicine. Results Significant changes were found between both 1st (46.0 ± 7.7) and 4th (37.8 ± 15.7) year students and 2nd (48.3 ± 7.8) and 4th (37.8 ± 15.7) year students. No significant difference was found between 1st (46.0 ± 7.7) and 2nd (48.3 ± 7.8) year students. When comparing scores based on gender, a significant difference was present between males (41.2 ± 12.2) and females (46.1 ± 11.0). Conclusion CHBQ scores were significantly more positive in both 1st and 2nd year medical students in comparison with 4th year student's scores. These findings suggest that as student exposure to allopathic techniques and procedures increases during the last year of medical school, their attitudes toward CAM decrease. Females were also significantly more likely to have stronger positive attitudes toward CAM than males, though both genders represented an overall positive attitude toward CAM. PMID:18799010

  19. Jordanian Kindergarten and 1st-Grade Teachers' Beliefs about Child-Based Dimensions of School Readiness

    ERIC Educational Resources Information Center

    Fayez, Merfat; Ahmad, Jamal Fathi; Oliemat, Enass

    2016-01-01

    The purpose of this study was to explore the beliefs of Jordanian kindergarten and 1st-grade teachers regarding six child-based dimensions of school readiness: academic knowledge, basic thinking skills, socioemotional maturity, physical well-being and motor development, self-discipline, and communication skills. Questionnaires were used to collect…

  20. 78 FR 7781 - Filing Dates for the South Carolina Special Elections in the 1st Congressional District

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-04

    ... From the Federal Register Online via the Government Publishing Office FEDERAL ELECTION COMMISSION Filing Dates for the South Carolina Special Elections in the 1st Congressional District AGENCY: Federal Election Commission. ACTION: Notice of filing dates for special elections. SUMMARY: South Carolina...

  1. Addressing the Effects of Reciprocal Teaching on the Receptive and Expressive Vocabulary of 1st-Grade Students

    ERIC Educational Resources Information Center

    Mandel, Eliana; Osana, Helena P.; Venkatesh, Vivek

    2013-01-01

    This study evaluated the effects of Adapted Reciprocal Teaching (ART) on the receptive and expressive flight-word vocabulary of 1st-grade students. During ART, classroom interactions produced narrative contexts within which students assumed responsibility for applying new flight words in personally meaningful ways. Students in the control group…

  2. Testing Pairwise Association between Spatially Autocorrelated Variables: A New Approach Using Surrogate Lattice Data

    PubMed Central

    Deblauwe, Vincent; Kennel, Pol; Couteron, Pierre

    2012-01-01

    Background Independence between observations is a standard prerequisite of traditional statistical tests of association. This condition is, however, violated when autocorrelation is present within the data. In the case of variables that are regularly sampled in space (i.e. lattice data or images), such as those provided by remote-sensing or geographical databases, this problem is particularly acute. Because analytic derivation of the null probability distribution of the test statistic (e.g. Pearson's r) is not always possible when autocorrelation is present, we propose instead the use of a Monte Carlo simulation with surrogate data. Methodology/Principal Findings The null hypothesis that two observed mapped variables are the result of independent pattern generating processes is tested here by generating sets of random image data while preserving the autocorrelation function of the original images. Surrogates are generated by matching the dual-tree complex wavelet spectra (and hence the autocorrelation functions) of white noise images with the spectra of the original images. The generated images can then be used to build the probability distribution function of any statistic of association under the null hypothesis. We demonstrate the validity of a statistical test of association based on these surrogates with both actual and synthetic data and compare it with a corrected parametric test and three existing methods that generate surrogates (randomization, random rotations and shifts, and iterative amplitude adjusted Fourier transform). Type I error control was excellent, even with strong and long-range autocorrelation, which is not the case for alternative methods. Conclusions/Significance The wavelet-based surrogates are particularly appropriate in cases where autocorrelation appears at all scales or is direction-dependent (anisotropy). We explore the potential of the method for association tests involving a lattice of binary data and discuss its potential for

  3. Robust Feature Extraction Using Variable Window Function in Autocorrelation Domain for Speech Recognition

    NASA Astrophysics Data System (ADS)

    Lee, Sangho; Ha, Jeonghyun; Hong, Jaekeun

    This paper presents a new feature extraction method for robust speech recognition based on the autocorrelation mel frequency cepstral coefficients (AMFCCs) and a variable window. While the AMFCC feature extraction method uses the fixed double-dynamic-range (DDR) Hamming window for higher-lag autocorrelation coefficients, which are least affected by noise, the proposed method applies a variable window, depending on the frame energy and periodicity. The performance of the proposed method is verified using an Aurora-2 task, and the results confirm a significantly improved performance under noisy conditions.

  4. Autocorrelation study of the Θ transition for a coarse-grained polymer model.

    PubMed

    Qi, Kai; Bachmann, Michael

    2014-08-21

    By means of Metropolis Monte Carlo simulations of a coarse-grained model for flexible polymers, we investigate how the integrated autocorrelation times of different energetic and structural quantities depend on the temperature. We show that, due to critical slowing down, an extremal autocorrelation time can also be considered as an indicator for the collapse transition that helps to locate the transition point. This is particularly useful for finite systems, where response quantities such as the specific heat do not necessarily exhibit clear indications for pronounced thermal activity.

  5. Suppression of image autocorrelation artefacts in spectral domain optical coherence tomography and multiwave digital holography

    SciTech Connect

    Gelikonov, V M; Gelikonov, G V; Terpelov, D A; Shabanov, D V; Shilyagin, P A

    2012-05-31

    An improved method for suppressing image artefacts in spectral domain optical coherence tomography (SD OCT) and multiwave digital holography, caused by the influence of coherent noise in the course of successive registration of an autocorrelation component and informative signal is reported. The method allows complete suppression of all types of coherent noises, provided that the sample of values used to record the autocorrelation component satisfies the conditions of Kotelnikov's theorem: in SD OCT - for the transverse structure of the studied medium, in multiwave digital holography - for the envelop function of the radiation source frequency tuning spectrum.

  6. Patterns of Irregular Burials in Western Europe (1st-5th Century A.D.)

    PubMed Central

    Milella, Marco; Mariotti, Valentina; Belcastro, Maria Giovanna; Knüsel, Christopher J.

    2015-01-01

    Background Irregular burials (IB—burials showing features that contrast with the majority of others in their geographic and chronological context) have been the focus of archaeological study because of their relative rarity and enigmatic appearance. Interpretations of IB often refer to supposed fear of the dead or to social processes taking place in time-specific contexts. However, a comprehensive and quantitative analysis of IB for various geographical contexts is still lacking, a fact that hampers any discussion of these burials on a larger scale. Methods Here, we collected a bibliographic dataset of 375 IB from both Britain and Continental Europe, altogether spanning a time period from the 1st to the 5th century AD. Each burial has been coded according to ten dichotomous variables, further analyzed by means of chi-squared tests on absolute frequencies, non-metric multidimensional scaling, and cluster analysis. Results Even acknowledging the limits of this study, and in particular the bias represented by the available literature, our results point to interesting patterns. Geographically, IB show a contrast between Britain and Continental Europe, possibly related to historical processes specific to these regions. Different types of IB (especially prone depositions and depositions with the cephalic extremity displaced) present a series of characteristics and associations between features that permit a more detailed conceptualization of these occurrences from a socio-cultural perspective that aids to elucidate their funerary meaning. Conclusions and Significance Altogether, the present work stresses the variability of IB, and the need to contextualize them in a proper archaeological and historical context. It contributes to the discussion of IB by providing a specific geographic and chronological frame of reference that supports a series of hypotheses about the cultural processes possibly underlying their occurrence. PMID:26115408

  7. Computational Simulations of Convergent Nozzles for the AIAA 1st Propulsion Aerodynamics Workshop

    NASA Technical Reports Server (NTRS)

    Dippold, Vance F., III

    2014-01-01

    Computational Fluid Dynamics (CFD) simulations were completed for a series of convergent nozzles in participation of the American Institute of Aeronautics and Astronautics (AIAA) 1st Propulsion Aerodynamics Workshop. The simulations were performed using the Wind-US flow solver. Discharge and thrust coefficients were computed for four axisymmetric nozzles with nozzle pressure ratios (NPR) ranging from 1.4 to 7.0. The computed discharge coefficients showed excellent agreement with available experimental data; the computed thrust coefficients captured trends observed in the experimental data, but over-predicted the thrust coefficient by 0.25 to 1.0 percent. Sonic lines were computed for cases with NPR >= 2.0 and agreed well with experimental data for NPR >= 2.5. Simulations were also performed for a 25 deg. conic nozzle bifurcated by a flat plate at NPR = 4.0. The jet plume shock structure was compared with and without the splitter plate to the experimental data. The Wind-US simulations predicted the shock structure well, though lack of grid resolution in the plume reduced the sharpness of the shock waves. Unsteady Reynolds-Averaged Navier-Stokes (URANS) simulations and Detached Eddy Simulations (DES) were performed at NPR = 1.6 for the 25 deg conic nozzle with splitter plate. The simulations predicted vortex shedding from the trailing edge of the splitter plate. However, the vortices of URANS and DES solutions appeared to dissipate earlier than observed experimentally. It is believed that a lack of grid resolution in the region of the vortex shedding may have caused the vortices to break down too soon

  8. PREFACE: 1st Conference on Light and Particle Beams in Materials Science 2013 (LPBMS2013)

    NASA Astrophysics Data System (ADS)

    Kumai, Reiji; Murakami, Youichi

    2014-04-01

    From 29-31 August 2013, the 1st International Conference on Light and Particle Beams in Materials Science, LPBMS 2013, took place in the Tsukuba International Congress Center in the city of Tsukuba, Japan. The conference was a continuation of the international series Synchrotron Radiation in Materials Science (SRMS), which started in 1994. The last one, SRMS-7, was held in Oxford UK 11-14 July 2010, where the International Advisory Committee (IAC) recommended the conference be enlarged to incorporate Materials Research from Neutron, Muon, and Slow Positron Sources, as well as the science emerging from Synchrotron Light Sources. The conference brought together contributions from academics and industrial researchers with a diverse background and experience from the physics, chemistry and engineering communities. The topics covered in the LPBMS2013 include strongly correlated electron systems, magnetism and magnetic materials, soft matter, interface and surface defects, catalysts, biomaterials, and ceramics. In the 3-day scientific program, the conference consisted of 9 plenary talks, 33 invited talks, 20 oral presentations, and 126 poster presentations. We are pleased to publish the proceedings of the LPBMS2013 in this volume of Journal of Physics: Conference Series. This volume contains 58 papers representing the work that was presented and discussed at the conference. We hope that this volume will promote further development of this interdisciplinary materials research emerging from synchrotron light, neutron, muon, and slow positron sciences. Finally, we would like to thank the International Advisory Committee (Chair: Professor G N Greaves), sponsors, all the participants and contributors for making possible this international meeting of researchers. Reiji Kumai & Youichi Murakami Conference photograph Details of the program and organizing committees are available in the pdf

  9. Exploring the effects of spatial autocorrelation when identifying key drivers of wildlife crop-raiding

    PubMed Central

    Songhurst, Anna; Coulson, Tim

    2014-01-01

    Few universal trends in spatial patterns of wildlife crop-raiding have been found. Variations in wildlife ecology and movements, and human spatial use have been identified as causes of this apparent unpredictability. However, varying spatial patterns of spatial autocorrelation (SA) in human–wildlife conflict (HWC) data could also contribute. We explicitly explore the effects of SA on wildlife crop-raiding data in order to facilitate the design of future HWC studies. We conducted a comparative survey of raided and nonraided fields to determine key drivers of crop-raiding. Data were subsampled at different spatial scales to select independent raiding data points. The model derived from all data was fitted to subsample data sets. Model parameters from these models were compared to determine the effect of SA. Most methods used to account for SA in data attempt to correct for the change in P-values; yet, by subsampling data at broader spatial scales, we identified changes in regression estimates. We consequently advocate reporting both model parameters across a range of spatial scales to help biological interpretation. Patterns of SA vary spatially in our crop-raiding data. Spatial distribution of fields should therefore be considered when choosing the spatial scale for analyses of HWC studies. Robust key drivers of elephant crop-raiding included raiding history of a field and distance of field to a main elephant pathway. Understanding spatial patterns and determining reliable socio-ecological drivers of wildlife crop-raiding is paramount for designing mitigation and land-use planning strategies to reduce HWC. Spatial patterns of HWC are complex, determined by multiple factors acting at more than one scale; therefore, studies need to be designed with an understanding of the effects of SA. Our methods are accessible to a variety of practitioners to assess the effects of SA, thereby improving the reliability of conservation management actions. PMID:25035800

  10. Statistical mapping of speckle autocorrelation for visualization of hyperaemic responses to cortical stimulation.

    PubMed

    Paul, Joseph S; Al Nashash, Hasan; Luft, Andreas R; Le, Thinh M

    2006-07-01

    Statistically mapped speckle autocorrelation images (SAR) were used to track the hemodynamically active perfusion regions in the rat cortex during and following DC current stimulation with high transverse spatial resolution (38 um). The SAR images provided a spatio-temporal information about the net activation patterns of Cerebral Blood Flow (CBF) changes over a period of time as against those changes for each frame interval estimated using spatial contrasts derived from the first order spatial statistics. Thus the information about the relative maxima of perfusion during a Transient Hyperaemic Episode (THE) across different regions in the imaging window could be identified without the need for actually having to estimate the spatial contrast maps of the imaged region for each frame contained in the time window of observation. With the application of DC stimulation, the regions with a high correlation in the temporal fluctuations were representative of the areas that underwent least changes in activation. By varying the intensity of stimulation, THEs were observed for stimulation current densities in the range 0.1-3.8 mA/mm2 using both the derived speckle contrast maps and concurrently on a Laser Doppler Flow meter, with its probe positioned 1 mm from the site of stimulation. For current densities below the lower threshold of stimulation, the SAR images revealed an unprecedented reduction in the surge amplitude at sites distal to the region of stimulation. This was accompanied by an increase in pixel areas representing minimally active regions of perfusion ("perfusion islets") with no identifiable peak in the hemodynamic responses estimated from speckle contrast variations. The SAR images can be a useful tool for visualization of slow wave perfusion dynamics during cortical stimulation.

  11. Temporal autocorrelation functions for movement rates from global positioning system radiotelemetry data.

    PubMed

    Boyce, Mark S; Pitt, Justin; Northrup, Joseph M; Morehouse, Andrea T; Knopff, Kyle H; Cristescu, Bogdan; Stenhouse, Gordon B

    2010-07-27

    Autocorrelation has been viewed as a problem in telemetry studies because sequential observations are not independent in time or space, therefore violating assumptions for statistical inference. Yet nearly all ecological and behavioural data are autocorrelated in both space and time. We argue that there is much to learn about the structure of ecological and behavioural data from patterns of autocorrelation. Such patterns include periodicity in movement and patchiness in spatial data, which can be characterized by an autocorrelogram, semivariogram or spectrum. We illustrate the utility of temporal autocorrelation functions (ACFs) for analysing step-length data from GPS telemetry of wolves (Canis lupus), cougars (Puma concolor), grizzly bears (Ursus arctos) and elk (Cervus elaphus) in western Alberta. ACFs often differ by season, reflecting differences in foraging behaviour. In wilderness landscapes, step-length ACFs for predators decay slowly to apparently random patterns, but sometimes display strong daily rhythms in areas of human disturbance. In contrast, step lengths of elk are consistently periodic, reflecting crepuscular activity.

  12. New Approaches for Calculating Moran’s Index of Spatial Autocorrelation

    PubMed Central

    Chen, Yanguang

    2013-01-01

    Spatial autocorrelation plays an important role in geographical analysis; however, there is still room for improvement of this method. The formula for Moran’s index is complicated, and several basic problems remain to be solved. Therefore, I will reconstruct its mathematical framework using mathematical derivation based on linear algebra and present four simple approaches to calculating Moran’s index. Moran’s scatterplot will be ameliorated, and new test methods will be proposed. The relationship between the global Moran’s index and Geary’s coefficient will be discussed from two different vantage points: spatial population and spatial sample. The sphere of applications for both Moran’s index and Geary’s coefficient will be clarified and defined. One of theoretical findings is that Moran’s index is a characteristic parameter of spatial weight matrices, so the selection of weight functions is very significant for autocorrelation analysis of geographical systems. A case study of 29 Chinese cities in 2000 will be employed to validate the innovatory models and methods. This work is a methodological study, which will simplify the process of autocorrelation analysis. The results of this study will lay the foundation for the scaling analysis of spatial autocorrelation. PMID:23874592

  13. SU-E-T-188: Commission of World 1st Commercial Compact PBS Proton System

    SciTech Connect

    Ding, X; Patel, B; Song, X; Syh, J; Syh, J; Zhang, J; Freund, D; Rosen, L; Wu, H

    2015-06-15

    Purpose: ProteusONE is the 1st commercial compact PBS proton system with an upstream scanning gantry and C230 cyclotron. We commissioned XiO and Raystation TPS simultaneously. This is a summary of beam data collection, modeling, and verification and comparison without range shiter for this unique system with both TPS. Methods: Both Raystation and XiO requires the same measurements data: (i) integral depth dose(IDDs) of single central spot measured in water tank; (ii) absolute dose calibration measured at 2cm depth of water with mono-energetic 10×10 cm2 field with spot spacing 4mm, 1MU per spot; and (iii) beam spot characteristics in air at 0cm and ± 20cm away from ISO. To verify the beam model for both TPS, same 15 cube plans were created to simulate different treatment sites, target volumes and positions. PDDs of each plan were measured using a Multi-layer Ionization Chamber(MLIC), absolute point dose verification were measured using PPC05 in water tank and patient-specific QA were measured using MatriXX PT, a 2D ion chamber array. Results: All the point dose measurements at midSOBP were within 2% for both XiO and Raystation. However, up to 5% deviations were observed in XiO’s plans at shallow depth while within 2% in Raystation plans. 100% of the ranges measured were within 1 mm with maximum deviation of 0.5 mm. 20 patient specific plan were generated and measured in 3 planes (distal, proximal and midSOBP) in Raystation. The average of gamma index is 98.7%±3% with minimum 94% Conclusions: Both TPS were successfully commissioned and can be safely deployed for clinical use for ProteusONE. Based on our clinical experience in PBS planning, user interface, function and workflow, we preferably use Raystation as our main clinical TPS. Gamma Index >95% at 3%/3 mm criteria is our institution action level for patient specific plan QAs.

  14. PREFACE: 1st-2nd Young Researchers Meetings in Rome - Proceedings

    NASA Astrophysics Data System (ADS)

    YRMR Organizing Committee; Cannuccia, E.; Mazzaferro, L.; Migliaccio, M.; Pietrobon, D.; Stellato, F.; Veneziani, M.

    2011-03-01

    Students in science, particularly in physics, face a fascinating and challenging future. Scientists have proposed very interesting theories, which describe the microscopic and macroscopic world fairly well, trying to match the quantum regime with cosmological scales. Between the extremes of this scenario, biological phenomena in all their complexity take place, challenging the laws we observe in the atomic and sub-atomic world. More and more accurate and complex experiments have been devised and these are now going to test the paradigms of physics. Notable experiments include: the Large Hadronic Collider (LHC), which is going to shed light on the physics of the Standard Model of Particles and its extensions; the Planck-Herschel satellites, which target a very precise measurement of the properties of our Universe; and the Free Electron Lasers facilities, which produce high-brilliance, ultrafast X-ray pulses, allowing the investigation of the fundamental processes of solid state physics, chemistry, and biology. These projects are the result of huge collaborations spread across the world, involving scientists belonging to different and complementary research fields: physicists, chemists, biologists and others, keen to make the best of these extraordinary laboratories. Even though each branch of science is experiencing a process of growing specialization, it is very important to keep an eye on the global picture, remaining aware of the deep interconnections between inherent fields. This is even more crucial for students who are beginning their research careers. These considerations motivated PhD students and young post-docs connected to the Roman scientific research area to organize a conference, to establish the background and the network for interactions and collaborations. This resulted in the 1st and 2nd Young Researchers Meetings in Rome (http://ryrm.roma2.infn.it), one day conferences aimed primarily at graduate students and post-docs, working in physics in Italy

  15. PREFACE: 1st International Conference on Mechanical Engineering Research 2011 (ICMER2011)

    NASA Astrophysics Data System (ADS)

    Abu Bakar, Rosli

    2012-09-01

    The year 2010 represented a significant milestone in the history of the Mechanical Engineering community with the organization of the first and second national level conferences (National Conference in Mechanical Engineering for Research, 1st and 2nd NCMER) at Universiti Malaysia Pahang on 26-27 May and 3-4 December 2010. The conferences attracted a large number of delegates from different premier academic and research institutions in the country to participate and share their research experiences at the conference. The International Conference on Mechanical Engineering Research (ICMER 2011) followed on from the first and second conferences due to good support from researchers. The ICMER 2011 is a good platform for researchers and postgraduate students to present their latest finding in research. The conference covers a wide range of topics including the internal combustion engine, machining processes, heat and mass transfer, fuel, biomechanical analysis, aerodynamic analysis, thermal comfort, computational techniques, design and simulation, automotive transmission, optimization techniques, hybrid electric vehicles, engine vibration, heat exchangers, finite element analysis, computational fluid dynamics, green energy, vehicle dynamics renewable energy, combustion, design, product development, advanced experimentation techniques, to name but a few. The international conference has helped to bridge the gap between researchers working at different institutions and in different countries to share their knowledge and has helped to motivate young scientists with their research. This has also given some clear direction for further research from the deliberations of the conference. Several people have contributed in different ways to the success of the conference. We thank the keynote speakers and all authors of the contributed papers, for the cooperation rendered to us in the publication of the CD conference proceedings. In particular, we would like to place on record our

  16. PREFACE: 1st International Conference on Sensing for Industry, Control, Communication & Security Technologies

    NASA Astrophysics Data System (ADS)

    Shuja Syed, Ahmed

    2013-12-01

    The 1st International Conference on Sensing for Industry, Control, Communication & Security Technologies (ICSICCST-2013), took place in Karachi, Pakistan, from 24-26 June 2013. It was organized by Indus University, Karachi, in collaboration with HEJ Research Institute of Chemistry, University of Karachi, Karachi. More than 80 abstracts were submitted to the conference and were double blind-reviewed by an international scientific committee. The topics of the Conference were: Video, Image & Voice Sensing Sensing for Industry, Environment, and Health Automation and Controls Laser Sensors and Systems Displays for Innovative Applications Emerging Technologies Unmanned, Robotic, and Layered Systems Sensing for Defense, Homeland Security, and Law Enforcement The title of the conference, 'Sensing for Industry, Control, Communication & Security Technologies' is very apt in capturing the main issues facing the industry of Pakistan and the world. We believe the sensing industry, particularly in Pakistan, is currently at a critical juncture of its development. The future of the industry will depend on how the industry players choose to respond to the challenge of global competition and opportunities arising from strong growth in the Asian region for which we are pleased to note that the conference covered a comprehensive spectrum of issues with an international perspective. This will certainly assist industry players to make informed decisions in shaping the future of the industry. The conference gathered qualified researchers from developed countries like USA, UK, Sweden, Saudi Arabia, China, South Korea and Malaysia etc whose expertise resulting from the research can be drawn upon to build an exploitable area of new technology that has potential Defense, Homeland Security, and Military applicability. More than 250 researchers/students attended the event and made the event great success as the turnout was 100%. An exceptional line-up of speakers spoke at the occasion. We want

  17. Effects of the April 1st, 2014 GLONASS Outage on GNSS Receivers

    NASA Astrophysics Data System (ADS)

    Blume, F.; Berglund, H. T.; Romero, I.; D'Anastasio, E.

    2014-12-01

    The use of multi-constellation GNSS receivers has been assumed as a way to increase system integrity both by increased coverage during normal operations and failover redundancy in the event of a constellation failure. At approximately 21:00 UTC on April 1st the entire GLONASS constellation was disrupted as illegal ephemeris uploaded to each satellite took effect simultaneously. The outage continued for more than 10 hours. While ephemeris were incorrect, pseudoranges were correctly broadcast on both L1 and L2 and carrier phases were not affected; in the best case, GNSS receivers could be expected to continue to track all signals including GLONASS and at the worst to continue to track GPS and other constellations. It became clear to operators of the GeoNet network in New Zealand that the majority of their 79 GLONASS-enabled receivers experienced total tracking failures. Further detailed analysis of data from these and 315 additional GLONASS-enabled stations worldwide showed that receiver tracking behavior was affected for most receiver brands and models, both for GLONASS and GPS. Findings regarding the impacts of the GLONASS outage on receiver behavior will be highlighted. We use data recorded by GLONASS enabled global sites for the days during, preceding and following the outage to evaluate the impact of the outage on tracking and positioning performance. We observe that for some receiver types the onboard receiver autonomous integrity monitoring (RAIM) failed to ignore the incorrect messages, resulting in degraded GLONASS and GPS tracking and in some cases complete tracking failures and significant data loss. In addition, many of the receivers with clock steering enabled showed outliers in their receiver clock bias estimates that also coincided with the outage. Our results show in detail how different brands, configurations, and distributions of receivers were affected to varying extents, but no common factors are apparent. This event shows that many manufacturers

  18. Cobble cam: Grain-size measurements of sand to boulder from digital photographs and autocorrelation analyses

    USGS Publications Warehouse

    Warrick, J.A.; Rubin, D.M.; Ruggiero, P.; Harney, J.N.; Draut, A.E.; Buscombe, D.

    2009-01-01

    A new application of the autocorrelation grain size analysis technique for mixed to coarse sediment settings has been investigated. Photographs of sand- to boulder-sized sediment along the Elwha River delta beach were taken from approximately 1??2 m above the ground surface, and detailed grain size measurements were made from 32 of these sites for calibration and validation. Digital photographs were found to provide accurate estimates of the long and intermediate axes of the surface sediment (r2 > 0??98), but poor estimates of the short axes (r2 = 0??68), suggesting that these short axes were naturally oriented in the vertical dimension. The autocorrelation method was successfully applied resulting in total irreducible error of 14% over a range of mean grain sizes of 1 to 200 mm. Compared with reported edge and object-detection results, it is noted that the autocorrelation method presented here has lower error and can be applied to a much broader range of mean grain sizes without altering the physical set-up of the camera (~200-fold versus ~6-fold). The approach is considerably less sensitive to lighting conditions than object-detection methods, although autocorrelation estimates do improve when measures are taken to shade sediments from direct sunlight. The effects of wet and dry conditions are also evaluated and discussed. The technique provides an estimate of grain size sorting from the easily calculated autocorrelation standard error, which is correlated with the graphical standard deviation at an r2 of 0??69. The technique is transferable to other sites when calibrated with linear corrections based on photo-based measurements, as shown by excellent grain-size analysis results (r2 = 0??97, irreducible error = 16%) from samples from the mixed grain size beaches of Kachemak Bay, Alaska. Thus, a method has been developed to measure mean grain size and sorting properties of coarse sediments. ?? 2009 John Wiley & Sons, Ltd.

  19. An integrated approach of auto-correlation functions and wavelet analysis applied to the wind meandering phenomenon

    NASA Astrophysics Data System (ADS)

    Mortarini, Luca; Cava, Daniela; Giostra, Umberto; Anfossi, Domenico

    2016-04-01

    Meandering is generally defined in terms of large 
variation of the wind direction due to a complex mix of motions on scales between the main turbulent eddies and the smallest mesoscale motions. There is not a general consensus on the physical causes of the motions responsible of the wind meandering during low-wind speed conditions. They include internal gravity waves, quasi-2D pancake motions, cold air drainage, solitons, vortices with either a horizontal axis or a vertical axis. In this work we present the analysis of wind and temperature data measured with two sonic anemometers in a low-wind stably stratified night observed during the Urban Turbulent Project (Torino, Italy). An original approach to estimate the meandering time scales of the wind velocity and temperature using two complementary methodologies is proposed. In the literature the meandering time-scale is evaluated fitting the Eulerian auto-correlation functions of the wind velocity with an oscillating theoretical behaviour on hourly datasets. First we extend this method considering the dependence of the time-scale on the dataset length considering longer datasets (1, 2, 3, 4 hours) and then we compare these results with a wavelet analysis. The continuous wavelet transform based on the Morlet basis is used to detect and characterize the time-scale of the wavelike oscillations both in the wind velocity and in the temperature signals. Moreover cross-wavelet spectra are used to identify the nature of the wavy patterns in order to discriminate the presence of gravity waves. The wavelet analysis corroborates the results obtained with the auto-correlation functions and opens new promising perspectives for the study of the meandering phenomenon.

  20. Non-isotropic noise correlation in PET data reconstructed by FBP but not by OSEM demonstrated using auto-correlation function

    PubMed Central

    Razifar, Pasha; Lubberink, Mark; Schneider, Harald; Långström, Bengt; Bengtsson, Ewert; Bergström, Mats

    2005-01-01

    Background Positron emission tomography (PET) is a powerful imaging technique with the potential of obtaining functional or biochemical information by measuring distribution and kinetics of radiolabelled molecules in a biological system, both in vitro and in vivo. PET images can be used directly or after kinetic modelling to extract quantitative values of a desired physiological, biochemical or pharmacological entity. Because such images are generally noisy, it is essential to understand how noise affects the derived quantitative values. A pre-requisite for this understanding is that the properties of noise such as variance (magnitude) and texture (correlation) are known. Methods In this paper we explored the pattern of noise correlation in experimentally generated PET images, with emphasis on the angular dependence of correlation, using the autocorrelation function (ACF). Experimental PET data were acquired in 2D and 3D acquisition mode and reconstructed by analytical filtered back projection (FBP) and iterative ordered subsets expectation maximisation (OSEM) methods. The 3D data was rebinned to a 2D dataset using FOurier REbinning (FORE) followed by 2D reconstruction using either FBP or OSEM. In synthetic images we compared the ACF results with those from covariance matrix. The results were illustrated as 1D profiles and also visualized as 2D ACF images. Results We found that the autocorrelation images from PET data obtained after FBP were not fully rotationally symmetric or isotropic if the object deviated from a uniform cylindrical radioactivity distribution. In contrast, similar autocorrelation images obtained after OSEM reconstruction were isotropic even when the phantom was not circular. Simulations indicated that the noise autocorrelation is non-isotropic in images created by FBP when the level of noise in projections is angularly variable. Comparison between 1D cross profiles on autocorrelation images obtained by FBP reconstruction and covariance matrices

  1. Teachers' Spatial Anxiety Relates to 1st-and 2nd-Graders' Spatial Learning

    ERIC Educational Resources Information Center

    Gunderson, Elizabeth A.; Ramirez, Gerardo; Beilock, Sian L.; Levine, Susan C.

    2013-01-01

    Teachers' anxiety about an academic domain, such as math, can impact students' learning in that domain. We asked whether this relation held in the domain of spatial skill, given the importance of spatial skill for success in math and science and its malleability at a young age. We measured 1st-and 2nd-grade teachers' spatial anxiety…

  2. Uncertainty Requirement Analysis for the Orbit, Attitude, and Burn Performance of the 1st Lunar Orbit Insertion Maneuver

    NASA Astrophysics Data System (ADS)

    Song, Young-Joo; Bae, Jonghee; Kim, Young-Rok; Kim, Bang-Yeop

    2016-12-01

    In this study, the uncertainty requirements for orbit, attitude, and burn performance were estimated and analyzed for the execution of the 1st lunar orbit insertion (LOI) maneuver of the Korea Pathfinder Lunar Orbiter (KPLO) mission. During the early design phase of the system, associate analysis is an essential design factor as the 1st LOI maneuver is the largest burn that utilizes the onboard propulsion system; the success of the lunar capture is directly affected by the performance achieved. For the analysis, the spacecraft is assumed to have already approached the periselene with a hyperbolic arrival trajectory around the moon. In addition, diverse arrival conditions and mission constraints were considered, such as varying periselene approach velocity, altitude, and orbital period of the capture orbit after execution of the 1st LOI maneuver. The current analysis assumed an impulsive LOI maneuver, and two-body equations of motion were adapted to simplify the problem for a preliminary analysis. Monte Carlo simulations were performed for the statistical analysis to analyze diverse uncertainties that might arise at the moment when the maneuver is executed. As a result, three major requirements were analyzed and estimated for the early design phase. First, the minimum requirements were estimated for the burn performance to be captured around the moon. Second, the requirements for orbit, attitude, and maneuver burn performances were simultaneously estimated and analyzed to maintain the 1st elliptical orbit achieved around the moon within the specified orbital period. Finally, the dispersion requirements on the B-plane aiming at target points to meet the target insertion goal were analyzed and can be utilized as reference target guidelines for a mid-course correction (MCC) maneuver during the transfer. More detailed system requirements for the KPLO mission, particularly for the spacecraft bus itself and for the flight dynamics subsystem at the ground control center

  3. Educational impact of a clinical anatomy workshop on 1st-year orthopedic and rheumatology fellows in Mexico City.

    PubMed

    Saavedra, M A; Villaseñor-Ovies, P; Harfush, L A; Navarro-Zarza, J E; Canoso, J J; Cruz-Domínguez, P; Vargas, A; Hernández-Díaz, C; Chiapas-Gasca, K; Camacho-Galindo, J; Alvarez-Nemegyei, J; Kalish, R A

    2016-05-01

    We aim to study the educational impact of a clinical anatomy workshop in 1st-year orthopedic and rheumatology fellows. First-year rheumatology fellows (N = 17) and a convenience sample of 1st-year orthopedic fellows (N = 14) from Mexico City in the 9th month of training participated in the study. The pre- and the post- workshop tests included the same 20 questions that had to be answered by identification or demonstration of relevant anatomical items. The questions, arranged by anatomical regions, were asked in five dynamic stations. Overall, the 31 participants showed an increase of correct answers, from a median of 6 (range 1 to 12) in the pre-workshop test, to a median of 14 (range 7 to 19) in the post-workshop test. In the pre-workshop test, the correct median answers were 7 (range 2 to 12) in the orthopedic fellows and 5 (range 1 to 10) in the rheumatology fellows (p = 0.297). Corresponding scores in the post-workshop were 15 (range 10 to 19) and 12 (range 7 to 18) (p = 0.026) showing a significant difference favoring the orthopedic group. Our clinical anatomy workshop was efficacious, in the short term, as a teaching instrument for 1st-year orthopedic and rheumatology fellows. The post-workshop scores, although significantly improved in both groups, particularly in the orthopedic fellows, were still suboptimal. Further refinements of our workshop might yield better results.

  4. The theoretical simulation on electrostatic distribution of 1st proximity region in proximity focusing low-light-level image intensifier

    NASA Astrophysics Data System (ADS)

    Zhang, Liandong; Bai, Xiaofeng; Song, De; Fu, Shencheng; Li, Ye; Duanmu, Qingduo

    2015-03-01

    Low-light-level night vision technology is magnifying low light level signal large enough to be seen by naked eye, which uses the photons - photoelectron as information carrier. Until the micro-channel plate was invented, it has been possibility for the realization of high performance and miniaturization of low-light-level night vision device. The device is double-proximity focusing low-light-level image intensifier which places a micro-channel plate close to photocathode and phosphor screen. The advantages of proximity focusing low-light-level night vision are small size, light weight, small power consumption, no distortion, fast response speed, wide dynamic range and so on. It is placed parallel to each other for Micro-channel plate (both sides of it with metal electrode), the photocathode and the phosphor screen are placed parallel to each other. The voltage is applied between photocathode and the input of micro-channel plate when image intensifier works. The emission electron excited by photo on the photocathode move towards to micro-channel plate under the electric field in 1st proximity focusing region, and then it is multiplied through the micro-channel. The movement locus of emission electrons can be calculated and simulated when the distributions of electrostatic field equipotential lines are determined in the 1st proximity focusing region. Furthermore the resolution of image tube can be determined. However the distributions of electrostatic fields and equipotential lines are complex due to a lot of micro-channel existing in the micro channel plate. This paper simulates electrostatic distribution of 1st proximity region in double-proximity focusing low-light-level image intensifier with the finite element simulation analysis software Ansoft maxwell 3D. The electrostatic field distributions of 1st proximity region are compared when the micro-channel plates' pore size, spacing and inclination angle ranged. We believe that the electron beam movement

  5. Autocorrelation and cross-correlation in time series of homicide and attempted homicide

    NASA Astrophysics Data System (ADS)

    Machado Filho, A.; da Silva, M. F.; Zebende, G. F.

    2014-04-01

    We propose in this paper to establish the relationship between homicides and attempted homicides by a non-stationary time-series analysis. This analysis will be carried out by Detrended Fluctuation Analysis (DFA), Detrended Cross-Correlation Analysis (DCCA), and DCCA cross-correlation coefficient, ρ(n). Through this analysis we can identify a positive cross-correlation between homicides and attempted homicides. At the same time, looked at from the point of view of autocorrelation (DFA), this analysis can be more informative depending on time scale. For short scale (days), we cannot identify auto-correlations, on the scale of weeks DFA presents anti-persistent behavior, and for long time scales (n>90 days) DFA presents a persistent behavior. Finally, the application of this new type of statistical analysis proved to be efficient and, in this sense, this paper can contribute to a more accurate descriptive statistics of crime.

  6. Full-field velocity imaging of red blood cells in capillaries with spatiotemporal demodulation autocorrelation

    NASA Astrophysics Data System (ADS)

    Wang, Mingyi; Zeng, Yaguang; Dong, Nannan; Liao, Riwei; Yang, Guojian

    2016-03-01

    We propose a full-field optical method for the label-free and quantitative mapping of the velocities of red blood cells (RBCs) in capillaries. It integrates spatiotemporal demodulation and an autocorrelation algorithm, and measures RBC velocity according to the ratio of RBC length to lag time. Conventionally, RBC length is assumed to be a constant and lag time is taken as a variable, while our method treats both of them as variables. We use temporal demodulation and the Butterworth spatial filter to separate RBC signal from background signal, based on which we obtain the RBC length by image segmentation and lag time by autocorrelation analysis. The RBC velocity calculated now is more accurate. The validity of our method is verified by an in vivo experiment on a mouse ear. Owing to its higher image signal-to-noise ratio, our method can be used for mapping RBC velocity in the turbid tissue case.

  7. High prevalence of blaCTX-M-1/IncI1/ST3 and blaCMY-2/IncI1/ST2 plasmids in healthy urban dogs in France.

    PubMed

    Haenni, Marisa; Saras, Estelle; Métayer, Véronique; Médaille, Christine; Madec, Jean-Yves

    2014-09-01

    In the community, close contacts between humans and dogs may promote the transfer of extended-spectrum beta-lactamase/plasmidic AmpC cephalosporinase (ESBL/pAmpC) genes. Large-scale prevalence studies on ESBL/pAmpC carriage in dogs are rare, and data on ESBL/pAmpC plasmids are even more limited. Here, a considerable rate of 18.5% ESBL/pAmpC carriers was found among 368 unrelated healthy dogs in Paris, France. This prevalence is much higher than the one found in healthy humans in the same city (6%) but close to that recently reported in dogs in China (24.5%). All isolates were identified as Escherichia coli, except one Salmonella enterica and one Klebsiella pneumoniae isolate. The sequence type 131 (ST131) clone was rare (2/73 isolates). Interestingly, two plasmids (blaCTX-M-1/IncI1/ST3 and blaCMY-2/IncI1/ST2) were unexpectedly highly predominant, raising the question of their successful spread. Considering that CTX-M-1 was recently found to be equally as abundant as CTX-M-15 in healthy Parisian subjects, the question of dogs being a CTX-M-1 reservoir for humans is open. Such a high prevalence of the blaCMY-2/IncI1/ST2 plasmid may result from the use of cephalexin in veterinary medicine, as previously demonstrated experimentally. In all, our study points out healthy urban dogs as a potential source of ESBL/pAmpC genes that can further disseminate to the human community.

  8. High Prevalence of blaCTX-M-1/IncI1/ST3 and blaCMY-2/IncI1/ST2 Plasmids in Healthy Urban Dogs in France

    PubMed Central

    Saras, Estelle; Métayer, Véronique; Médaille, Christine; Madec, Jean-Yves

    2014-01-01

    In the community, close contacts between humans and dogs may promote the transfer of extended-spectrum beta-lactamase/plasmidic AmpC cephalosporinase (ESBL/pAmpC) genes. Large-scale prevalence studies on ESBL/pAmpC carriage in dogs are rare, and data on ESBL/pAmpC plasmids are even more limited. Here, a considerable rate of 18.5% ESBL/pAmpC carriers was found among 368 unrelated healthy dogs in Paris, France. This prevalence is much higher than the one found in healthy humans in the same city (6%) but close to that recently reported in dogs in China (24.5%). All isolates were identified as Escherichia coli, except one Salmonella enterica and one Klebsiella pneumoniae isolate. The sequence type 131 (ST131) clone was rare (2/73 isolates). Interestingly, two plasmids (blaCTX-M-1/IncI1/ST3 and blaCMY-2/IncI1/ST2) were unexpectedly highly predominant, raising the question of their successful spread. Considering that CTX-M-1 was recently found to be equally as abundant as CTX-M-15 in healthy Parisian subjects, the question of dogs being a CTX-M-1 reservoir for humans is open. Such a high prevalence of the blaCMY-2/IncI1/ST2 plasmid may result from the use of cephalexin in veterinary medicine, as previously demonstrated experimentally. In all, our study points out healthy urban dogs as a potential source of ESBL/pAmpC genes that can further disseminate to the human community. PMID:24982072

  9. Synchronous self-elimination of autocorrelation interference in Fourier-domain optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Ai, Jun; Wang, Lihong V.

    2005-11-01

    We have developed a new algorithm and configuration for self-eliminating the autocorrelation of the object wave in Fourier-domain optical coherence tomography. A self-interferogram of the object wave is acquired synchronously with the standard interferogram of the recombined object and reference waves. The former is then subtracted from the latter after Fourier transformation. The algorithm is validated by numerical simulation and by experimental measurement of a U.S. Air Force target and a feline eye.

  10. Analytical form of the autocorrelation function for the fluorescence correlation spectroscopy.

    PubMed

    Hołyst, Robert; Poniewierski, Andrzej; Zhang, Xuzhu

    2017-02-08

    Fluorescence correlation spectroscopy (FCS) can provide information about diffusion coefficients and rate constants of chemical reactions in small systems of interacting molecules. However, the interpretation of FCS experiments depends crucially on the model of the autocorrelation function for the fluorescence intensity fluctuations. In this theoretical work, we consider a system of fluorescent molecules that diffuse and interact with massive particles, e.g. surfactant micelles. Using the general formalism of FCS, we derive a new analytical approximation of the autocorrelation function for systems in which both diffusion and a binary reaction occur. This approximation provides a smooth interpolation between the limit of fast reaction (much faster than diffusion), and the opposite limit of slow reaction. Our studies of noncovalent interactions of micelles with dyes by FCS provided an experimental case to which the approximate autocorrelation function was successfully applied [X. Zhang, A. Poniewierski, A. Jelińska, A. Zagożdżon, A. Wisniewska, S. Hou and R. Hołyst, Soft Matter, 2016, 12, 8186-8194].

  11. Effect of the spatial autocorrelation of empty sites on the evolution of cooperation

    NASA Astrophysics Data System (ADS)

    Zhang, Hui; Wang, Li; Hou, Dongshuang

    2016-02-01

    An evolutionary game model is constructed to investigate the spatial autocorrelation of empty sites on the evolution of cooperation. Each individual is assumed to imitate the strategy of the one who scores the highest in its neighborhood including itself. Simulation results illustrate that the evolutionary dynamics based on the Prisoner's Dilemma game (PD) depends severely on the initial conditions, while the Snowdrift game (SD) is hardly affected by that. A high degree of autocorrelation of empty sites is beneficial for the evolution of cooperation in the PD, whereas it shows diversification effects depending on the parameter of temptation to defect in the SD. Moreover, for the repeated game with three strategies, 'always defect' (ALLD), 'tit-for-tat' (TFT), and 'always cooperate' (ALLC), simulations reveal that an amazing evolutionary diversity appears for varying of parameters of the temptation to defect and the probability of playing in the next round of the game. The spatial autocorrelation of empty sites can have profound effects on evolutionary dynamics (equilibrium and oscillation) and spatial distribution.

  12. Adaptive Bessel-autocorrelation of ultrashort pulses with phase-only spatial light modulators

    NASA Astrophysics Data System (ADS)

    Huferath-von Luepke, Silke; Bock, Martin; Grunwald, Ruediger

    2009-06-01

    Recently, we proposed a new approach of a noncollinear correlation technique for ultrashort-pulsed coherent optical signals which was referred to as Bessel-autocorrelator (BAC). The BAC-principle combines the advantages of Bessellike nondiffracting beams like stable propagation, angular robustness and self-reconstruction with the principle of temporal autocorrelation. In comparison to other phase-sensitive measuring techniques, autocorrelation is most straightforward and time-effective because of non-iterative data processing. The analysis of nonlinearly converted fringe patterns of pulsed Bessel-like beams reveals their temporal signature from details of fringe envelopes. By splitting the beams with axicon arrays into multiple sub-beams, transversal resolution is approximated. Here we report on adaptive implementations of BACs with improved phase resolution realized by phase-only liquid-crystal-on-silicon spatial light modulators (LCoS-SLMs). Programming microaxicon phase functions in gray value maps enables for a flexible variation of phase and geometry. Experiments on the diagnostics of few-cycle pulses emitted by a mode-locked Ti:sapphire laser oscillator at wavelengths around 800 nm with 2D-BAC and angular tuned BAC were performed. All-optical phase shift BAC and fringe free BAC approaches are discussed.

  13. A new radial strain and strain rate estimation method using autocorrelation for carotid artery

    NASA Astrophysics Data System (ADS)

    Ye, Jihui; Kim, Hoonmin; Park, Jongho; Yeo, Sunmi; Shim, Hwan; Lim, Hyungjoon; Yoo, Yangmo

    2014-03-01

    Atherosclerosis is a leading cause of cardiovascular disease. The early diagnosis of atherosclerosis is of clinical interest since it can prevent any adverse effects of atherosclerotic vascular diseases. In this paper, a new carotid artery radial strain estimation method based on autocorrelation is presented. In the proposed method, the strain is first estimated by the autocorrelation of two complex signals from the consecutive frames. Then, the angular phase from autocorrelation is converted to strain and strain rate and they are analyzed over time. In addition, a 2D strain image over region of interest in a carotid artery can be displayed. To evaluate the feasibility of the proposed radial strain estimation method, radiofrequency (RF) data of 408 frames in the carotid artery of a volunteer were acquired by a commercial ultrasound system equipped with a research package (V10, Samsung Medison, Korea) by using a L5-13IS linear array transducer. From in vivo carotid artery data, the mean strain estimate was -0.1372 while its minimum and maximum values were -2.961 and 0.909, respectively. Moreover, the overall strain estimates are highly correlated with the reconstructed M-mode trace. Similar results were obtained from the estimation of the strain rate change over time. These results indicate that the proposed carotid artery radial strain estimation method is useful for assessing the arterial wall's stiffness noninvasively without increasing the computational complexity.

  14. PREFACE: PAGES 1st Young Scientists Meeting (YSM) - 'Retrospective views on our planet's future'

    NASA Astrophysics Data System (ADS)

    Cléroux, Caroline; Fehrenbacher, Jennifer; Phipps, Steven; Rupper, Summer; Williams, Branwen; Kiefer, Thorsten

    2010-03-01

    more recent pollution. The concept and format of the 1st PAGES YSM worked very well, and created a high degree of enthusiasm and stimulation among the participants (as is demonstrated by this special issue). The 2nd YSM is therefore firmly planned to take place in 2013, back-to-back with the 4th PAGES OSM. Crucial and gratefully acknowledged contributions to the success of the YSM were made by the numerous co-sponsors (see logos below), who provided the financial basis for the YSM and supported the attendance of many early-career researchers from various parts of the world. Furthermore, we cordially thank all reviewers for shaping this proceeding issue with their insightful and helpful reviews. Conference photograph

  15. Calling depths of baleen whales from single sensor data: development of an autocorrelation method using multipath localization.

    PubMed

    Valtierra, Robert D; Glynn Holt, R; Cholewiak, Danielle; Van Parijs, Sofie M

    2013-09-01

    Multipath localization techniques have not previously been applied to baleen whale vocalizations due to difficulties in application to tonal vocalizations. Here it is shown that an autocorrelation method coupled with the direct reflected time difference of arrival localization technique can successfully resolve location information. A derivation was made to model the autocorrelation of a direct signal and its overlapping reflections to illustrate that an autocorrelation may be used to extract reflection information from longer duration signals containing a frequency sweep, such as some calls produced by baleen whales. An analysis was performed to characterize the difference in behavior of the autocorrelation when applied to call types with varying parameters (sweep rate, call duration). The method's feasibility was tested using data from playback transmissions to localize an acoustic transducer at a known depth and location. The method was then used to estimate the depth and range of a single North Atlantic right whale (Eubalaena glacialis) and humpback whale (Megaptera novaeangliae) from two separate experiments.

  16. The autocorrelation of the Möbius function and Chowla's conjecture for the rational function field in characteristic 2

    PubMed Central

    Carmon, Dan

    2015-01-01

    We prove a function field version of Chowla's conjecture on the autocorrelation of the Möbius function in the limit of a large finite field of characteristic 2, extending previous work in odd characteristic. PMID:25802413

  17. Iron Sappers Lead the Way: The 16th Engineer Battalion’s Support of 1st Armored Division in Southwest Asia

    DTIC Science & Technology

    1993-03-30

    limited value due to the availability of double impulse, blast resistant mines and the success of the tank plow. The GEMSS ( ground emplaced mine...34 Ironsides (Ansbach, Germany), 5 July 1991, p. 10. Headquarters, Phantom Brigade, 1st Armored Division. "DESERT SHIELD and DESERT STORM After Action...govemment agency. IRON SAPPERS LEAD THE WAY: THE 16TH ENGINEER BATTALION’S SUPPORT OF 1ST ARMORED DIVISION IN SOUTHWEST ASIA BY LIEUTENANT COLONEL

  18. A Predictive Risk Model for A(H7N9) Human Infections Based on Spatial-Temporal Autocorrelation and Risk Factors: China, 2013–2014

    PubMed Central

    Dong, Wen; Yang, Kun; Xu, Quan-Li; Yang, Yu-Lian

    2015-01-01

    This study investigated the spatial distribution, spatial autocorrelation, temporal cluster, spatial-temporal autocorrelation and probable risk factors of H7N9 outbreaks in humans from March 2013 to December 2014 in China. The results showed that the epidemic spread with significant spatial-temporal autocorrelation. In order to describe the spatial-temporal autocorrelation of H7N9, an improved model was developed by introducing a spatial-temporal factor in this paper. Logistic regression analyses were utilized to investigate the risk factors associated with their distribution, and nine risk factors were significantly associated with the occurrence of A(H7N9) human infections: the spatial-temporal factor φ (OR = 2546669.382, p < 0.001), migration route (OR = 0.993, p < 0.01), river (OR = 0.861, p < 0.001), lake(OR = 0.992, p < 0.001), road (OR = 0.906, p < 0.001), railway (OR = 0.980, p < 0.001), temperature (OR = 1.170, p < 0.01), precipitation (OR = 0.615, p < 0.001) and relative humidity (OR = 1.337, p < 0.001). The improved model obtained a better prediction performance and a higher fitting accuracy than the traditional model: in the improved model 90.1% (91/101) of the cases during February 2014 occurred in the high risk areas (the predictive risk > 0.70) of the predictive risk map, whereas 44.6% (45/101) of which overlaid on the high risk areas (the predictive risk > 0.70) for the traditional model, and the fitting accuracy of the improved model was 91.6% which was superior to the traditional model (86.1%). The predictive risk map generated based on the improved model revealed that the east and southeast of China were the high risk areas of A(H7N9) human infections in February 2014. These results provided baseline data for the control and prevention of future human infections. PMID:26633446

  19. Texture synthesis and classification using fractional lower order moments

    NASA Astrophysics Data System (ADS)

    Kulkarni, Anita; Chouikha, Mohamed F.

    1995-03-01

    Fractional lower order moments (FLOMs) based on the non-Gaussian stable distribution are employed for texture classification and synthesis. The parameters of a 2D autoregression model are estimated using the fractional lower order moments, and these parameters are used for texture classification. The analysis of FLOMs is useful when the variance of the underlying distribution is not finite and thus when the whole second-order statistics theory fails; hence, parameter estimation using FLOMs gives a more robust model over the existing methods that use autocorrelation function. This stable distribution is used in the synthesis of texture, and the performance of FLOMs and the autocorrelation methods are compared. By extensive simulations it is shown that the FLOM-based feature extraction algorithm outperforms the autocorrelation-based one.

  20. [Report of the World Federation of Neurosurgical Societies (WFNS) international course and Cameroon Neurosurgery Society Congress (CNS) Yaoundé (Cameroon), 1st--4th October 2007].

    PubMed

    Eyenga, V C; Ndoumbe, A; Eloundou, N J

    2008-04-01

    Neurosurgery remains a very marginal activity in sub-Saharan Africa. In this part of the world which counts nearly 40 countries, some do not have a single neurosurgeon, some have one to five, the number of ten neurosurgeons per country remaining an exception! In its concern of popularizing and of developing neurosurgery worldwide, the WFNS organized an international course in Africa, October 2007 2nd-3rd in Yaoundé (Cameroon). The Cameroon Neurosurgery Society (CNS) took this opportunity to organize its very first congress in the presence of the WFNS delegation from October 1st to 4th, 2007. The joint meeting with the WFNS was baptized the "African Week of Neurosurgery". This special event was a first in sub-Saharan Africa. The delegation of the WFNS, led by Professor J. Brotchi (Belgium) President of the WFNS, was made up of Professors A. Sousa (Brazil), Mr. Choux (France), N. Tribolet (Swiss), M. Arraez (Spain), A. Bricolo (Italy), A. Kamlichi (Morocco), G. Dechambenoit (France), K. Kalangu (Zimbabwe). Twenty three neurosurgeons coming from nine African countries (Cameroon, Nigeria, Gabon, Congo, Niger, Burkina Faso, Ivory Coast, Senegal, and Guinea) took an active part in work. The scientific success of this event led to the creation of the "Association of Neurological Surgeons of Africa (ANSA)" which will be the WFNS-Africa interface in order to insure the development of neurosurgery in Africa.

  1. The 1ST Battalion 7TH Infantry in the Gulf War

    DTIC Science & Technology

    1993-03-23

    equipment and supplies but otherwise encountered no organized opposition. After refueling at PL NEW MEXICO , the task force was ordered to move and occupy...r c &s ,.n cor e -F ri: e Lav I < v. -i N P e j H QN. r el r-m . r et q .c~a r,-:c::o;1 crw’ . . Cae nc, o~ estr -*:,Y, tr, -& (5,~r- C~d 7o~nrce...the A/L channels. Contaminated remains will be conspicuously marked and located. D. CIVILIAN LABOR - Availability is controlled by LAD. E

  2. Evaluation of an Extended Autocorrelation Phase Estimator for Ultrasonic Velocity Profiles Using Nondestructive Testing Systems.

    PubMed

    Ofuchi, César Yutaka; Coutinho, Fabio Rizental; Neves, Flávio; de Arruda, Lucia Valéria Ramos; Morales, Rigoberto Eleazar Melgarejo

    2016-08-09

    In this paper the extended autocorrelation velocity estimator is evaluated and compared using a nondestructive ultrasonic device. For this purpose, three velocity estimators are evaluated and compared. The autocorrelation method (ACM) is the most used and well established in current ultrasonic velocity profiler technology, however, the technique suffers with phase aliasing (also known as the Nyquist limit) at higher velocities. The cross-correlation method (CCM) is also well known and does not suffer with phase aliasing as it relies on time shift measurements between emissions. The problem of this method is the large computational burden due to several required mathematical operations. Recently, an extended autocorrelation method (EAM) which combines both ACM and CCM was developed. The technique is not well known within the fluid engineering community, but it can measure velocities beyond the Nyquist limit without the ACM phase aliasing issues and with a lower computational cost than CCM. In this work, all three velocity estimation methods are used to measure a uniform flow of the liquid inside a controlled rotating cylinder. The root-mean-square deviation variation coefficient (CVRMSD) of the velocity estimate and the reference cylinder velocity was used to evaluate the three different methods. Results show that EAM correctly measures velocities below the Nyquist limit with less than 2% CVRMSD. Velocities beyond the Nyquist limit are only measured well by EAM and CCM, with the advantage of the former of being computationally 15 times faster. Furthermore, the maximum value of measurable velocity is also investigated considering the number of times the velocity surpasses the Nyquist limit. The combination of number of pulses and number of samples, which highly affects the results, are also studied in this work. Velocities up to six times the Nyquist limit could be measurable with CCM and EAM using a set of parameters as suggested in this work. The results validate

  3. Structure of the North Anatolian Fault Zone from the Autocorrelation of Ambient Seismic Noise

    NASA Astrophysics Data System (ADS)

    Taylor, George; Rost, Sebastian; Houseman, Gregory

    2016-04-01

    In recent years the technique of cross-correlating the ambient seismic noise wavefield at two seismometers to reconstruct empirical Green's Functions for the determination of Earth structure has been a powerful tool to study the Earth's interior without earthquakes or man-made sources. However, far less attention has been paid to using auto-correlations of seismic noise to reveal body wave reflections from interfaces in the subsurface. In principle, the Green's functions thus derived should be comparable to the Earth's impulse response to a co-located source and receiver. We use data from a dense seismic array (Dense Array for Northern Anatolia - DANA) deployed across the northern branch of the North Anatolian Fault Zone (NAFZ) in the region of the 1999 magnitude 7.6 Izmit earthquake in western Turkey. The NAFZ is a major strike-slip system that extends ~1200 km across northern Turkey and continues to pose a high level of seismic hazard, in particular to the mega-city of Istanbul. We construct body wave images for the entire crust and the shallow upper mantle over the ~35 km by 70 km footprint of the 70-station DANA array. Using autocorrelations of the vertical component of ground motion, P-wave reflections can be retrieved from the wavefield to constrain crustal structure. We show that clear P-wave reflections from the crust-mantle boundary (Moho) can be retrieved using the autocorrelation technique, indicating topography on the Moho on horizontal scales of less than 10 km. Offsets in crustal structure can be identified that seem to be correlated with the surface expression of the northern branch of the fault zone, indicating that the NAFZ reaches the upper mantle as a narrow structure. The southern branch has a less clear effect on crustal structure. We also see evidence of several discontinuities in the mid-crust in addition to an upper mantle reflector that we interpret to represent the Hales discontinuity.

  4. Evaluation of an Extended Autocorrelation Phase Estimator for Ultrasonic Velocity Profiles Using Nondestructive Testing Systems

    PubMed Central

    Ofuchi, César Yutaka; Coutinho, Fabio Rizental; Neves, Flávio; de Arruda, Lucia Valéria Ramos; Morales, Rigoberto Eleazar Melgarejo

    2016-01-01

    In this paper the extended autocorrelation velocity estimator is evaluated and compared using a nondestructive ultrasonic device. For this purpose, three velocity estimators are evaluated and compared. The autocorrelation method (ACM) is the most used and well established in current ultrasonic velocity profiler technology, however, the technique suffers with phase aliasing (also known as the Nyquist limit) at higher velocities. The cross-correlation method (CCM) is also well known and does not suffer with phase aliasing as it relies on time shift measurements between emissions. The problem of this method is the large computational burden due to several required mathematical operations. Recently, an extended autocorrelation method (EAM) which combines both ACM and CCM was developed. The technique is not well known within the fluid engineering community, but it can measure velocities beyond the Nyquist limit without the ACM phase aliasing issues and with a lower computational cost than CCM. In this work, all three velocity estimation methods are used to measure a uniform flow of the liquid inside a controlled rotating cylinder. The root-mean-square deviation variation coefficient (CVRMSD) of the velocity estimate and the reference cylinder velocity was used to evaluate the three different methods. Results show that EAM correctly measures velocities below the Nyquist limit with less than 2% CVRMSD. Velocities beyond the Nyquist limit are only measured well by EAM and CCM, with the advantage of the former of being computationally 15 times faster. Furthermore, the maximum value of measurable velocity is also investigated considering the number of times the velocity surpasses the Nyquist limit. The combination of number of pulses and number of samples, which highly affects the results, are also studied in this work. Velocities up to six times the Nyquist limit could be measurable with CCM and EAM using a set of parameters as suggested in this work. The results validate

  5. Positron-electron autocorrelation function study of E-center in silicon

    NASA Astrophysics Data System (ADS)

    Ho, K. F.; Ching, H. M.; Beling, C. D.; Fung, S.; Ng, K. P.; Biasini, M.; Ferro, G.; Gong, M.

    2003-11-01

    Two-dimensional angular correlation of annihilation radiation (2D-ACAR) spectra have been taken for 1019cm-3 phosphorus-doped Si in the as-grown state after having been subjected to 1.8 MeV electron fluences of 1×1018 and 2×1018 cm-2. Positron annihilation lifetime spectroscopy confirms, in accordance with previous works, that positrons are saturation trapping into (VSi:P) pair defect (E-center) monovacancy sites in the electron irradiated samples. In the as-grown case, the positron-electron autocorrelation functions along the [111] and [1-10] directions, obtained through Fourier transformation of the 2D-ACAR data, reveal zero-crossings that deviate only slightly from the lattice points, in a manner consistent with positron-electron correlation effects. Conversely, in the spectra of the irradiated samples, the zero-crossing points are observed to move outward further by between 0.15 and 0.50 Å. This displacement is associated with positron annihilation with electrons in localized orbitals at the defect site. An attempt is made to extract just the component of the defect's positron-electron autocorrelation function that relates to the localized defect orbitals. In doing this features are found that correspond to the expected atomic positions at the vacancy defect site suggesting that this real-space function may provide a convenient means for obtaining a mapping of localized orbitals. The observed approximate separability of positron and electron wave-function autocorrelates leads to an estimate of 0.22 eV for the positron binding energy to the E-center.

  6. New autocorrelation technique for the IR FEL optical pulse width measurements

    SciTech Connect

    Amirmadhi, F.; Brau, K.A.; Becker, C.

    1995-12-31

    We have developed a new technique for the autocorrelation measurement of optical pulse width at the Vanderbilt University FEL center. This method is based on nonlinear absorption and transmission characteristics of semiconductors such as Ge, Te and InAs suitable for the wavelength range from 2 to over 6 microns. This approach, aside being simple and low cost, removes the phase matching condition that is generally required for the standard frequency doubling technique and covers a greater wavelength range per nonlinear material. In this paper we will describe the apparatus, explain the principal mechanism involved and compare data which have been acquired with both frequency doubling and two-photon absorption.

  7. Autocorrelation noise removal for optical coherence tomography by sparse filter design

    NASA Astrophysics Data System (ADS)

    Seck, Hon Luen; Zhang, Ying; Soh, Yeng Chai

    2012-07-01

    We present a reconstruction method to eliminate the autocorrelation noise (ACN) in optical coherence tomography (OCT). In this method, the optical fields scattered from the sample features are regarded as the response of a sparse finite impulse response (FIR) filter. Then the OCT reconstruction is formulated as one of identifying the parameters of a sparse FIR filter, which are obtained via an ℓ1 optimization with soft thresholding. The experimental results show that the proposed method can obtain OCT reconstruction results with effective attenuation of ACN.

  8. Sign reversals of the output autocorrelation function for the stochastic Bernoulli-Verhulst equation

    SciTech Connect

    Lumi, N. Mankin, R.

    2015-10-28

    We consider a stochastic Bernoulli-Verhulst equation as a model for population growth processes. The effect of fluctuating environment on the carrying capacity of a population is modeled as colored dichotomous noise. Relying on the composite master equation an explicit expression for the stationary autocorrelation function (ACF) of population sizes is found. On the basis of this expression a nonmonotonic decay of the ACF by increasing lag-time is shown. Moreover, in a certain regime of the noise parameters the ACF demonstrates anticorrelation as well as related sign reversals at some values of the lag-time. The conditions for the appearance of this highly unexpected effect are also discussed.

  9. New Markov-autocorrelation indices for re-evaluation of links in chemical and biological complex networks used in metabolomics, parasitology, neurosciences, and epidemiology.

    PubMed

    González-Díaz, Humberto; Riera-Fernández, Pablo

    2012-12-21

    The development of new methods for the computational re-evaluation of links in chemical and biological complex networks is very important to save time and resources. The Moreau-Broto autocorrelation indices (MBis) are well-known topological indices (TIs) used in QSAR/QSPR studies to encode the structural information contained in molecular graphs. In addition, MBis and similar autocorrelation measures have been used to study other systems like, for example, proteins. In the present work, MBis are combined with Markov chains to develop a general class of stochastic MBis of order k (MB(k)) that is used to encode the structural information contained in different types of large complex networks. The MB(k) values obtained for the nodes (centralities) of these networks are used as input variables to seek QSPR-like equations (by means of linear discriminant analysis) in which the outputs are numerical scores S(L(ij)) that allow us to discriminate between connected and nonconnected nodes and therefore re-evaluate the connectivity of the whole network. The models developed in this work produced the following results in terms of overall accuracy for network reconstruction: metabolic networks (72.10%), parasite-host networks (88.70%), CoCoMac brain cortex coactivation network (81.89%), and fasciolosis spreading network (86.39%).

  10. Time-to-contact estimation of accelerated stimuli is based on first-order information.

    PubMed

    Benguigui, Nicolas; Ripoll, Hubert; Broderick, Michael P

    2003-12-01

    The goal of this study was to test whether 1st-order information, which does not account for acceleration, is used (a) to estimate the time to contact (TTC) of an accelerated stimulus after the occlusion of a final part of its trajectory and (b) to indirectly intercept an accelerated stimulus with a thrown projectile. Both tasks require the production of an action on the basis of predictive information acquired before the arrival of the stimulus at the target and allow the experimenter to make quantitative predictions about the participants' use (or nonuse) of 1st-order information. The results show that participants do not use information about acceleration and that they commit errors that rely quantitatively on 1st-order information even when acceleration is psychophysically detectable. In the indirect interceptive task, action is planned about 200 ms before the initiation of the movement, at which time the 1st-order TTC attains a critical value.

  11. Impact of volcanic eruptions on the climate of the 1st millennium AD in a comprehensive climate simulation

    NASA Astrophysics Data System (ADS)

    Wagner, Sebastian; Zorita, Eduardo

    2015-04-01

    The climate of the 1st millennium AD shows some remarkable differences compared to the last millennium concerning variation in external forcings. Together with an orbitally induced increased solar insolation during the northern hemisphere summer season and a general lack of strong solar minima, the frequency and intensity of large tropical and extratropical eruptions is decreased. Here we present results of a new climate simulation carried out with the comprehensive Earth System Model MPI-ESM-P forced with variations in orbital, solar, volcanic and greenhouse gas variations and land use changes for the last 2,100 years. The atmospheric model has a horizontal resolution of T63 (approx. 125x125 km) and therefore also allows investigations of regional-to-continental scale climatic phenomena. The volcanic forcing was reconstructed based on a publication by Sigl et al. (2013) using the sulfate records of the NEEM and WAIS ice cores. To obtain information on the aerosol optical depth (AOD) these sulfate records were scaled to an established reconstruction from Crowley and Unterman (2010), which is also a standard forcing in the framework of CMIP5/PMIP3. A comparison between the newly created data set with the Crowley and Unterman dataset reveals that the new reconstruction shows in general weaker intensities, especially of the large tropical outbreaks and fewer northern hemispheric small-to-medium scale eruptions. However, the general pattern in the overlapping period is similar. A hypothesis that can be tested with the simulation is whether the reduced volcanic intensity of the 1st millennium AD contributed to the elevated temperature levels over Europe, evident within a new proxy-based reconstruction. On the other hand, the few but large volcanic eruptions, e.g. the 528 AD event, also induced negative decadal-scale temperature anomalies. Another interesting result of the simulation relates to the 79 AD eruption of the Vesuvius, which caused the collapse of the city of

  12. Improving conversion yield of fermentable sugars into fuel ethanol in 1st generation yeast-based production processes.

    PubMed

    Gombert, Andreas K; van Maris, Antonius J A

    2015-06-01

    Current fuel ethanol production using yeasts and starch or sucrose-based feedstocks is referred to as 1st generation (1G) ethanol production. These processes are characterized by the high contribution of sugar prices to the final production costs, by high production volumes, and by low profit margins. In this context, small improvements in the ethanol yield on sugars have a large impact on process economy. Three types of strategies used to achieve this goal are discussed: engineering free-energy conservation, engineering redox-metabolism, and decreasing sugar losses in the process. Whereas the two former strategies lead to decreased biomass and/or glycerol formation, the latter requires increased process and/or yeast robustness.

  13. A compositional study of a museum jewellery collection (7th-1st BC) by means of a portable XRF spectrometer

    NASA Astrophysics Data System (ADS)

    Karydas, A. G.; Kotzamani, D.; Bernard, R.; Barrandon, J. N.; Zarkadas, Ch.

    2004-11-01

    Within the framework of the project "Jewelmed" (ICA3-1999-10020), the chemical composition of 34 gold and four silver jewels was examined. These jewels belong to the Benaki museum's collection in Athens, Greece and are dating from the 7th to the 1st century BC. The compositional analysis of the jewels was performed by means of a "home-made" portable X-ray fluorescence (XRF) spectrometer. The XRF results have shown that the gold jewels can be categorized in two groups, which include artifacts made by native and by high purity gold, respectively. For the silver jewels the results have provided interesting information regarding the manufacturing technology, the authenticity of the jewels and the raw materials used. The potential and the limitations of the XRF technique, applied in the chemical analysis of archaeological metal artifacts, are also discussed.

  14. Plasma properties from the multi-wavelength analysis of the November 1st 2003 CME/shock event.

    PubMed

    Benna, Carlo; Mancuso, Salvatore; Giordano, Silvio; Gioannini, Lorenzo

    2013-05-01

    The analysis of the spectral properties and dynamic evolution of a CME/shock event observed on November 1st 2003 in white-light by the LASCO coronagraph and in the ultraviolet by the UVCS instrument operating aboard SOHO, has been performed to compute the properties of some important plasma parameters in the middle corona below about 2R ⊙. Simultaneous observations obtained with the MLSO/Mk4 white-light coronagraph, providing both the early evolution of the CME expansion in the corona and the pre-shock electron density profile along the CME front, were also used to study this event. By combining the above information with the analysis of the metric type II radio emission detected by ground-based radio spectrographs, we finally derive estimates of the values of the local Alfvén speed and magnetic field strength in the solar corona.

  15. Acceptance tests and their results for 1st Pre-Series Cryoline (PTCL) of ITER

    NASA Astrophysics Data System (ADS)

    Kapoor, H.; Garg, A.; Shah, N.; Muralidhara, S.; Choukekar, K.; Dash, B.; Gaur, V.; Madeenavalli, S.; Patel, P.; Kumar, U.; Jadon, M.; Shukla, V.; Sarkar, B.; Sarvaiya, Y.; Mukherjee, D.; Dutta, A.; Murugan, KV.; Gajera, S.; Joshi, B.; Panjwani, R.

    2017-02-01

    The Pre-Series Cryoline (PTCL) for ITER is a representative cryoline from the complicated network of all cryolines for the ITER project. It is ∼28 m in length with same cross-section (1:1) including main line (ML) and branch line (BL) as of ITER torus & cryostat cryoline. Geometrically; it has bends at different angles i.e. 90°, 120°, 135° & 160° comprising T-section & Z-section. The PTCL has been fabricated in 5 different elements based on the installation feasibility. The mechanical & instrumentation installation like sensors mounting, displacement sensors, etc. has been completed. The PTCL test has been performed after complete installation of PTCL and integration with the existing test facility at ITER-India cryogenics laboratory in order to verify the thermal performance and mechanical integrity. The primary objectives, which are evaluated during the PTCL test, are (i) Thermal performance of the PTCL (ii) Measurement of temperature profile on thermal shield of PTCL, (iii) Stress measurement at critical locations, (iv) Measurement of Outer Vacuum Jacket (OVJ) temperature during Break of Insulation Vacuum (BIV) test. The paper will summarize the methodology and observed results of PTCL.

  16. Dispersal leads to spatial autocorrelation in species distributions: A simulation model

    USGS Publications Warehouse

    Bahn, V.; Krohn, W.B.; O'Connor, R.J.

    2008-01-01

    Compared to population growth regulated by local conditions, dispersal has been underappreciated as a central process shaping the spatial distribution of populations. This paper asks: (a) which conditions increase the importance of dispersers relative to local recruits in determining population sizes? and (b) how does dispersal influence the spatial distribution patterns of abundances among connected populations? We approached these questions with a simulation model of populations on a coupled lattice with cells of continuously varying habitat quality expressed as carrying capacities. Each cell contained a population with the basic dynamics of density-regulated growth, and was connected to other populations by immigration and emigration. The degree to which dispersal influenced the distribution of population sizes depended most strongly on the absolute amount of dispersal, and then on the potential population growth rate. Dispersal decaying in intensity with distance left close neighbours more alike in population size than distant populations, leading to an increase in spatial autocorrelation. The spatial distribution of species with low potential growth rates is more dependent on dispersal than that of species with high growth rates; therefore, distribution modelling for species with low growth rates requires particular attention to autocorrelation, and conservation management of these species requires attention to factors curtailing dispersal, such as fragmentation and dispersal barriers. ?? 2007 Elsevier B.V. All rights reserved.

  17. Time autocorrelation function analysis of master equation and its application to atomic clusters.

    PubMed

    Zhang, Chi; Berry, R Stephen

    2005-09-01

    We derive the energy fluctuation Delta(2)E, and the time autocorrelation kappa(tau) and its Fourier transformation--the fluctuation spectra S(omega)--of the master-equation transition matrix. The contribution from each eigenmode of the transition matrix to these fluctuation quantities reveals the relevant importance of the individual mode in the relaxation processes. The time scales associated with these relaxation processes are determined by the corresponding eigenvalues. Unlike traditional time evolution analysis, the autocorrelation function and fluctuation spectra analysis does not involve an arbitrary initial population. It is also more suitable for analyzing the underlying dynamic, kinetic behavior near the equilibrium and the behavior of the long-time-scale rare events. We utilize our technique to analyze the solid-liquid phase coexistence of the 13-atom Morse cluster and the fcc-to-icosahedral structure transition of the 38-atom Lennard-Jones cluster. For the processes studied, the fluctuation spectra from the master equation simplify the analysis of the transition matrix, and the important relaxation modes are easily extracted.

  18. Temporal and spatiotemporal autocorrelation of daily concentrations of Alnus, Betula, and Corylus pollen in Poland.

    PubMed

    Nowosad, J; Stach, A; Kasprzyk, I; Grewling, Ł; Latałowa, M; Puc, M; Myszkowska, D; Weryszko-Chmielewska, E; Piotrowska-Weryszko, K; Chłopek, K; Majkowska-Wojciechowska, B; Uruska, A

    The aim of the study was to determine the characteristics of temporal and space-time autocorrelation of pollen counts of Alnus, Betula, and Corylus in the air of eight cities in Poland. Daily average pollen concentrations were monitored over 8 years (2001-2005 and 2009-2011) using Hirst-designed volumetric spore traps. The spatial and temporal coherence of data was investigated using the autocorrelation and cross-correlation functions. The calculation and mathematical modelling of 61 correlograms were performed for up to 25 days back. The study revealed an association between temporal variations in Alnus, Betula, and Corylus pollen counts in Poland and three main groups of factors such as: (1) air mass exchange after the passage of a single weather front (30-40 % of pollen count variation); (2) long-lasting factors (50-60 %); and (3) random factors, including diurnal variations and measurements errors (10 %). These results can help to improve the quality of forecasting models.

  19. Onsets, autocorrelation functions and spikes for direction-based sound source separation

    NASA Astrophysics Data System (ADS)

    Smith, Leslie S.; Fraser, Dagmar S.

    2005-04-01

    The aim of this work is separation of foreground speech from background sound sources using selective remixing of bandpass filtered channels. Clearly, the remixing parameters must be dynamic since the speech and noise spectra are highly non-stationary. Remixing parameters are recomputed at onsets, detected using biologically motivated techniques [L. S. Smith and D. S. Fraser, IEEE TNNS 15, 1125-1134 (2004)]. However, onsets may originate from the foreground or the background. To select appropriate onsets from the foreground source (whose direction is known) a two microphone system is used, selecting onsets for which the estimated direction in that channel corresponds to the foreground direction. Two different techniques for direction estimation are used: a channel by channel short-term autocorrelation technique, and a channel by channel spike based phase synchronous system (SBPSS), computing ITDs [L. S. Smith, in Artificial Neural Networks, Proc ICANN 2001, LNCS 2130, pp. 1103-1108 (Springer, 2001)] and IIDs [L. S. Smith, in From Animals to Animats, Vol. 7, pp. 60-61 (MIT Press, 2002)]. Results comparing the performance of autocorrelation and SBPSS on single source and source plus noise signals in an office environment are presented. [Work supported by UK EPSRC.

  20. [Cervix priming in induced abortion in the 1st trimester using intracervical administration of sulprostone gel].

    PubMed

    Rath, W; Meyer, D; Harder, D; Hilgers, R; Kuhn, W

    1985-01-01

    In a prospective, randomised study 40 primigravidae were treated intracervically with 0.05 mg or 0.1 mg Sulprostone-Tylose gel in order to soften the cervix prior to first trimester termination of pregnancy. Curettage was performed on the average 7.5 hours after prostaglandin administration. For objective demonstration of the priming effect, the force required for dilatation of the cervical canal was measured in Newtons by a special tonometer before prostaglandin application and before operation. The maximal dilatability with a force of 10 N, the increase in dilatability after local PG application, and the patency of the cervix were measured. The occurrence of PG-induced lower abdominal pain associated with contractions was analysed with regard to the number of episodes at pain, their timing and the required amount of analgesics. A modified visual analogue scale was used to evaluate the subjective pain experience. The abortive effect of 0.1 mg Sulprostone was found to be more efficient than the 0.05 mg dose. There was no statistical significant difference between the two doses, however, for the priming effect detectable with the tonometer. The subjective experience of pain, use of analgesics and the frequency of gastrointestinal side effects were significantly higher with 0.1 mg than with 0.05 mg Sulprostone. The visual analogue scale allows the patient to quantify, at least to some extent, her experience of pain, and enables a differentiated analgetic therapy. Because of its effectiveness and low rate of side effects, the intracervical application of 0.05 mg Sulprostone gel promises to be an advantageous alternative to other methods of cervical priming.

  1. Experience from the 1st Year running a Massive High Quality Videoconferencing Service for the LHC

    NASA Astrophysics Data System (ADS)

    Fernandes, Joao; Baron, Thomas; Bompastor, Bruno

    2014-06-01

    In the last few years, we have witnessed an explosion of visual collaboration initiatives in the industry. Several advances in video services and also in their underlying infrastructure are currently improving the way people collaborate globally. These advances are creating new usage paradigms: any device in any network can be used to collaborate, in most cases with an overall high quality. To keep apace with this technology progression, the CERN IT Department launched a service based on the Vidyo product. This new service architecture introduces Adaptive Video Layering, which dynamically optimizes the video for each endpoint by leveraging the H.264 Scalable Video Coding (SVC)-based compression technology. It combines intelligent AV routing techniques with the flexibility of H.264 SVC video compression, in order to achieve resilient video collaboration over the Internet, 3G and WiFi. We present an overview of the results that have been achieved after this major change. In particular, the first year of operation of the CERN Vidyo service will be described in terms of performance and scale: The service became part of the daily activity of the LHC collaborations, reaching a monthly usage of more than 3200 meetings with a peak of 750 simultaneous connections. We also present some key features such as the integration with CERN Indico. LHC users can now join a Vidyo meeting either from their personal computer or a CERN videoconference room simply from an Indico event page, with the ease of a single click. The roadmap for future improvements, service extensions and core infrastructure tendencies such as cloud based services and virtualization of system components will also be discussed. Vidyo's strengths allowed us to build a universal service (it is accessible from PCs, but also videoconference rooms, traditional phones, tablets and smartphones), developed with 3 key ideas in mind: ease of use, full integration and high quality.

  2. Performing the triple auto-correlation of picosecond optical pulse train with a photo electromotive force detector

    NASA Astrophysics Data System (ADS)

    Shcherbakov, Alexandre S.; Mansurova, Svetlana; Moreno Zarate, Pedro; Campos Acosta, Joaquin; Nemov, Sergey A.

    2011-03-01

    vHere, we consider the possibility of involving the photo-EMF detectors in registration of the parameters peculiar to ultrashort optical pulses, and it is compared whit the recently triple correlator via Direct and Cascade Third Harmonic Generation. Knowledge of triple auto-correlation function, whose Fourier transformation shapes the corresponding bispectrum, makes possible recovering such train-average parameters as, for instance, the pulse width and frequency chirp as well as revealing asymmetry of ultra-short pulse envelope. The main advantage of applying the photo-EMF detectors lies in an opportunity to detect triple correlations directly, without any intermediate frequency conversion with optical nonlinear processes in additional crystals. Then, the theory of three-beam-correlations at photosensitive layer of the photo-EMF detector is developed, so that principal possibility of registering the high-order-correlations is demonstrated. It can be done within schematic arrangement including the three-beam Michelson interferometer, so that the obtained high-order-correlations have non-traditional form and need rather specific algorithm for their further processing. Also, the experimental characterizations are presented for gallium arsenide (GaAs) semiconductor and the poly-fluoren 6-co-triphenyldiamine (PF6-TPD) photo-conductor-polymer, which both exhibit the photo-EMF-effect. They both exhibit high-pass transfer functions that give us high vibration stability. This novel approach provides more reliable analyzing train-average parameters of picosecond pulses due to significantly higher level of the output optical signals under processing.

  3. Adaptive and Effortful Control and Academic Self-efficacy Beliefs on Achievement: A Longitudinal Study of 1st through 3rd Graders

    PubMed Central

    Liew, Jeffrey; McTigue, Erin; Barrois, Lisa; Hughes, Jan

    2009-01-01

    The linkages between self-regulatory processes and achievement were examined across three years in 733 children beginning at 1st grade (M = 6.57 years, SD = .39 at 1st grade) who were identified as lower achieving in literacy. Accounting for consistencies in measures (from one year prior) and for influences of child’s age, gender, IQ, ethnicity and economic adversity on achievement, results indicate that adaptive/effortful control at 1st grade contributed to both academic self-efficacy beliefs at 2nd grade, and reading (but not math) achievement at 3rd grade. Although academic self-efficacy did not partially mediate the linkage between adaptive/effortful control and achievement, academic self-efficacy beliefs were positively correlated with reading and math. Results support the notion that early efforts to promote children’s self-regulatory skills would enhance future academic self-beliefs and achievement, particularly in literacy. PMID:19169387

  4. Cloud 3D Effects Evidenced in Landsat Power Spectra and Autocorrelation Functions

    NASA Technical Reports Server (NTRS)

    Oreopoulos, Lazaros; Marshak, Alexander; Cahalan, Robert F.; Wen, Guoyong

    1999-01-01

    An analysis of nadir reflectivity Fourier spatial power spectra and autocorrelation functions at solar wavelengths and for cloudy conditions has been carried out. The data come from Landsat Thematic Mapper (TM) observations, while Monte Carlo (MC) simulations are used to aid the interpretation of the Landsat results. We show that radiative processes produce consistent signatures on power spectra and autocorrelation functions. The former take a variety of forms not shown or explained in previous observational studies. We demonstrate that the TM spectra can potentially be affected by both radiative "roughening" at intermediate scales (approx. 1 -5 km), being more prevalent at large solar zenith angles, and the already documented radiative "smoothing" at small scales (less than 1 km). These processes are wavelength dependent, as shown by systematic differences between conservative (for cloud droplets) TM band 4 (approx. 0.8 microns) and absorbing band 7 (approx. 2.2 microns): band 7 exhibits more roughening and less smoothing. This is confirmed quantitatively by comparing least-squared fitted power spectral slopes for the two bands. It is also corroborated by a slower decrease with distance of autocorrelation function values for band 4 compared to band 7. The appearance of roughening at large solar zenith angles is a result of side illumination and shadowing and adds an additional complexity to the power spectra. MC spectra are useful in illustrating that scale invariant optical depth fields can produce complex power spectra that take a variety of shapes under different conditions. We show that radiative roughening increases with the decrease of single scattering albedo and with the increase of solar zenith angle (as in the observations). For high Sun there is also a clear shift of the radiative smoothing scale to smaller values as droplet absorption increases. The shape of the power spectrum is sensitive to the magnitude and type of cloud top height variability, with

  5. Velocity autocorrelation function in supercooled liquids: Long-time tails and anomalous shear-wave propagation

    NASA Astrophysics Data System (ADS)

    Peng, H. L.; Schober, H. R.; Voigtmann, Th.

    2016-12-01

    Molecular dynamic simulations are performed to reveal the long-time behavior of the velocity autocorrelation function (VAF) by utilizing the finite-size effect in a Lennard-Jones binary mixture. Whereas in normal liquids the classical positive t-3 /2 long-time tail is observed, we find in supercooled liquids a negative tail. It is strongly influenced by the transfer of the transverse current wave across the period boundary. The t-5 /2 decay of the negative long-time tail is confirmed in the spectrum of VAF. Modeling the long-time transverse current within a generalized Maxwell model, we reproduce the negative long-time tail of the VAF, but with a slower algebraic t-2 decay.

  6. Geary autocorrelation and DCCA coefficient: Application to predict apoptosis protein subcellular localization via PSSM

    NASA Astrophysics Data System (ADS)

    Liang, Yunyun; Liu, Sanyang; Zhang, Shengli

    2017-02-01

    Apoptosis is a fundamental process controlling normal tissue homeostasis by regulating a balance between cell proliferation and death. Predicting subcellular location of apoptosis proteins is very helpful for understanding its mechanism of programmed cell death. Prediction of apoptosis protein subcellular location is still a challenging and complicated task, and existing methods mainly based on protein primary sequences. In this paper, we propose a new position-specific scoring matrix (PSSM)-based model by using Geary autocorrelation function and detrended cross-correlation coefficient (DCCA coefficient). Then a 270-dimensional (270D) feature vector is constructed on three widely used datasets: ZD98, ZW225 and CL317, and support vector machine is adopted as classifier. The overall prediction accuracies are significantly improved by rigorous jackknife test. The results show that our model offers a reliable and effective PSSM-based tool for prediction of apoptosis protein subcellular localization.

  7. A simple autocorrelation algorithm for determining grain size from digital images of sediment

    USGS Publications Warehouse

    Rubin, D.M.

    2004-01-01

    Autocorrelation between pixels in digital images of sediment can be used to measure average grain size of sediment on the bed, grain-size distribution of bed sediment, and vertical profiles in grain size in a cross-sectional image through a bed. The technique is less sensitive than traditional laboratory analyses to tails of a grain-size distribution, but it offers substantial other advantages: it is 100 times as fast; it is ideal for sampling surficial sediment (the part that interacts with a flow); it can determine vertical profiles in grain size on a scale finer than can be sampled physically; and it can be used in the field to provide almost real-time grain-size analysis. The technique can be applied to digital images obtained using any source with sufficient resolution, including digital cameras, digital video, or underwater digital microscopes (for real-time grain-size mapping of the bed). ?? 2004, SEPM (Society for Sedimentary Geology).

  8. Artificial fingerprint recognition by using optical coherence tomography with autocorrelation analysis

    NASA Astrophysics Data System (ADS)

    Cheng, Yezeng; Larin, Kirill V.

    2006-12-01

    Fingerprint recognition is one of the most widely used methods of biometrics. This method relies on the surface topography of a finger and, thus, is potentially vulnerable for spoofing by artificial dummies with embedded fingerprints. In this study, we applied the optical coherence tomography (OCT) technique to distinguish artificial materials commonly used for spoofing fingerprint scanning systems from the real skin. Several artificial fingerprint dummies made from household cement and liquid silicone rubber were prepared and tested using a commercial fingerprint reader and an OCT system. While the artificial fingerprints easily spoofed the commercial fingerprint reader, OCT images revealed the presence of them at all times. We also demonstrated that an autocorrelation analysis of the OCT images could be potentially used in automatic recognition systems.

  9. Artificial fingerprint recognition by using optical coherence tomography with autocorrelation analysis.

    PubMed

    Cheng, Yezeng; Larin, Kirill V

    2006-12-20

    Fingerprint recognition is one of the most widely used methods of biometrics. This method relies on the surface topography of a finger and, thus, is potentially vulnerable for spoofing by artificial dummies with embedded fingerprints. In this study, we applied the optical coherence tomography (OCT) technique to distinguish artificial materials commonly used for spoofing fingerprint scanning systems from the real skin. Several artificial fingerprint dummies made from household cement and liquid silicone rubber were prepared and tested using a commercial fingerprint reader and an OCT system. While the artificial fingerprints easily spoofed the commercial fingerprint reader, OCT images revealed the presence of them at all times. We also demonstrated that an autocorrelation analysis of the OCT images could be potentially used in automatic recognition systems.

  10. Time autocorrelation function and Green-Kubo formula: study on a disordered harmonic chain.

    PubMed

    Kundu, Anupam

    2010-09-01

    We have considered heat conduction in a one-dimensional mass-disordered harmonic chain of N particles connected to two Langevin type reservoirs at different temperatures. An exact expression for the boundary heat current-current autocorrelation function in the nonequilibrium steady state (NESS) is obtained in terms of nonequilibrium phonon Green's functions. The time integral of the correlation function gives expected result, both in nonequilibrium as well as equilibrium cases. Using the form of this correlation function we show that asymptotic system size dependence of current fluctuation in NESS for a mass-disordered harmonic chain is N(-α) for different boundary conditions. For free and fixed boundary conditions we get α=1/2 and 3/2, respectively, while for pinned case the fluctuation decays exponentially with system size.

  11. Velocity autocorrelation spectra in molten polymers measured by NMR modulated gradient spin-echo

    NASA Astrophysics Data System (ADS)

    Stepišnik, Janez; Mohorič, Aleš; Mattea, Carlos; Stapf, Siegfried; Serša, Igor

    2014-04-01

    The segmental dynamics in molten linear polymers is studied by the NMR method of modulated gradient spin-echo, which directly probes a spectrum of molecular velocity autocorrelation function. Diffusion spectra of mono-disperse poly(isoprene-1.4) with different molecular masses, measured in the frequency range 0.1-10 kHz at a temperature of 26\\ ^{\\circ}\\text{C} , have a form similar to the spectrum of Rouse chain dynamics, which implicates the tube-Rouse motion as the dominant dynamic process in this frequency range. The scaling of the center-of-mass diffusion coefficient, given from the fitting parameters, changes from N^{-1} into N^{-2.4} at around N \\approx 3\\text{-}5 Kuhn steps, which is less than predicted by theory and simulations, while the correlation times of the tube-Rouse mode do not follow the anticipated scaling.

  12. Autocorrelation spectra of an air-fluidized granular system measured by NMR

    NASA Astrophysics Data System (ADS)

    Lasic, S.; Stepisnik, J.; Mohoric, A.; Sersa, I.; Planinsic, G.

    2006-09-01

    A novel insight into the dynamics of a fluidized granular system is given by a nuclear magnetic resonance method that yields the spin-echo attenuation proportional to the spectrum of the grain positional fluctuation. Measurements of the air-fluidized oil-filled spheres and mustard seeds at different degrees of fluidization and grain volume fractions provide the velocity autocorrelation that differs from the commonly anticipated exponential Enskog decay. An empiric formula, which corresponds to the model of grain caging at collisions with adjacent beads, fits well to the experimental data. Its parameters are the characteristic collision time, the free path between collisions and the cage-breaking rate or the diffusion-like constant, which decreases with increasing grain volume fraction. Mean-squared displacements calculated from the correlation spectrum clearly show transitions from ballistic, through sub-diffusion and into diffusion regimes of grain motion.

  13. ISAR Imaging of Ship Targets Based on an Integrated Cubic Phase Bilinear Autocorrelation Function.

    PubMed

    Zheng, Jibin; Liu, Hongwei; Liu, Zheng; Liu, Qing Huo

    2017-03-03

    For inverse synthetic aperture radar (ISAR) imaging of a ship target moving with ocean waves, the image constructed with the standard range-Doppler (RD) technique is blurred and the range-instantaneous-Doppler (RID) technique has to be used to improve the image quality. In this paper, azimuth echoes in a range cell of the ship target are modeled as noisy multicomponent cubic phase signals (CPSs) after the motion compensation and a RID ISAR imaging algorithm is proposed based on the integrated cubic phase bilinear autocorrelation function (ICPBAF). The ICPBAF is bilinear and based on the two-dimensionally coherent energy accumulation. Compared to five other estimation algorithms, the ICPBAF can acquire higher cross term suppression and anti-noise performance with a reasonable computational cost. Through simulations and analyses with the synthetic model and real radar data, we verify the effectiveness of the ICPBAF and corresponding RID ISAR imaging algorithm.

  14. ISAR Imaging of Ship Targets Based on an Integrated Cubic Phase Bilinear Autocorrelation Function

    PubMed Central

    Zheng, Jibin; Liu, Hongwei; Liu, Zheng; Liu, Qing Huo

    2017-01-01

    For inverse synthetic aperture radar (ISAR) imaging of a ship target moving with ocean waves, the image constructed with the standard range-Doppler (RD) technique is blurred and the range-instantaneous-Doppler (RID) technique has to be used to improve the image quality. In this paper, azimuth echoes in a range cell of the ship target are modeled as noisy multicomponent cubic phase signals (CPSs) after the motion compensation and a RID ISAR imaging algorithm is proposed based on the integrated cubic phase bilinear autocorrelation function (ICPBAF). The ICPBAF is bilinear and based on the two-dimensionally coherent energy accumulation. Compared to five other estimation algorithms, the ICPBAF can acquire higher cross term suppression and anti-noise performance with a reasonable computational cost. Through simulations and analyses with the synthetic model and real radar data, we verify the effectiveness of the ICPBAF and corresponding RID ISAR imaging algorithm. PMID:28273800

  15. Extension of the spatial autocorrelation (SPAC) method to mixed-component correlations of surface waves

    USGS Publications Warehouse

    Haney, Matthew M.; Mikesell, T. Dylan; van Wijk, Kasper; Nakahara, Hisashi

    2012-01-01

    Using ambient seismic noise for imaging subsurface structure dates back to the development of the spatial autocorrelation (SPAC) method in the 1950s. We present a theoretical analysis of the SPAC method for multicomponent recordings of surface waves to determine the complete 3 × 3 matrix of correlations between all pairs of three-component motions, called the correlation matrix. In the case of isotropic incidence, when either Rayleigh or Love waves arrive from all directions with equal power, the only non-zero off-diagonal terms in the matrix are the vertical–radial (ZR) and radial–vertical (RZ) correlations in the presence of Rayleigh waves. Such combinations were not considered in the development of the SPAC method. The method originally addressed the vertical–vertical (ZZ), RR and TT correlations, hence the name spatial autocorrelation. The theoretical expressions we derive for the ZR and RZ correlations offer additional ways to measure Rayleigh wave dispersion within the SPAC framework. Expanding on the results for isotropic incidence, we derive the complete correlation matrix in the case of generally anisotropic incidence. We show that the ZR and RZ correlations have advantageous properties in the presence of an out-of-plane directional wavefield compared to ZZ and RR correlations. We apply the results for mixed-component correlations to a data set from Akutan Volcano, Alaska and find consistent estimates of Rayleigh wave phase velocity from ZR compared to ZZ correlations. This work together with the recently discovered connections between the SPAC method and time-domain correlations of ambient noise provide further insights into the retrieval of surface wave Green’s functions from seismic noise.

  16. Importance of spatial autocorrelation in modeling bird distributions at a continental scale

    USGS Publications Warehouse

    Bahn, V.; O'Connor, R.J.; Krohn, W.B.

    2006-01-01

    Spatial autocorrelation in species' distributions has been recognized as inflating the probability of a type I error in hypotheses tests, causing biases in variable selection, and violating the assumption of independence of error terms in models such as correlation or regression. However, it remains unclear whether these problems occur at all spatial resolutions and extents, and under which conditions spatially explicit modeling techniques are superior. Our goal was to determine whether spatial models were superior at large extents and across many different species. In addition, we investigated the importance of purely spatial effects in distribution patterns relative to the variation that could be explained through environmental conditions. We studied distribution patterns of 108 bird species in the conterminous United States using ten years of data from the Breeding Bird Survey. We compared the performance of spatially explicit regression models with non-spatial regression models using Akaike's information criterion. In addition, we partitioned the variance in species distributions into an environmental, a pure spatial and a shared component. The spatially-explicit conditional autoregressive regression models strongly outperformed the ordinary least squares regression models. In addition, partialling out the spatial component underlying the species' distributions showed that an average of 17% of the explained variation could be attributed to purely spatial effects independent of the spatial autocorrelation induced by the underlying environmental variables. We concluded that location in the range and neighborhood play an important role in the distribution of species. Spatially explicit models are expected to yield better predictions especially for mobile species such as birds, even in coarse-grained models with a large extent. ?? Ecography.

  17. Molecular-dynamics calculations of the velocity-autocorrelation function. Methods, hard-disk results

    NASA Astrophysics Data System (ADS)

    Erpenbeck, Jerome J.; Wood, William W.

    1982-09-01

    The velocity-autocorrelation function ρD(t) for hard disks is computed for ten values of the reduced volume, ranging from 30 to 1.4 times the close-packed volume (V0) for systems of as few as 168 and as many as 5822 particles, by a Monte Carlo molecular-dynamics technique. For values of the time greater than roughly 20 mean-free times (t0), the results are compared with the predictions of a version of the mode-coupling theory for ρD(t), modified to take into account the finite size of the system. Except at the highest densities, the data agree with the modified theory when one uses Knskog values for the transport coefficients in evaluating the theoretical ρD(t), provided the comparison is limited to times beyond a value sit0, with si dependent on the density. The value of si appears to increase from roughly 20 at the lowest densities to 40 at a volume of 2V0. At volumes of 1.6, 1.5, and 1.4V0, the theoretical ρD(t)'s are too large out to times as large as 320t0, unless we use values of the transport coefficients rather larger than the Enskog values in evaluating the theoretical ρD(t). The velocity-autocorrelation-function results for t<20t0 are presented as the difference relative to the Lorentz-Boltzmann-Enskog prediction, which has the exact slope at t=0.

  18. Establishment of the 1st World Health Organization International Standard for Plasmodium falciparum DNA for nucleic acid amplification technique (NAT)-based assays

    PubMed Central

    Padley, David J; Heath, Alan B; Sutherland, Colin; Chiodini, Peter L; Baylis, Sally A

    2008-01-01

    Background In order to harmonize results for the detection and quantification of Plasmodium falciparum DNA by nucleic acid amplification technique (NAT)-based assays, a World Health Organization (WHO) collaborative study was performed, evaluating a series of candidate standard preparations. Methods Fourteen laboratories from 10 different countries participated in the collaborative study. Four candidate preparations based upon blood samples parasitaemic for P. falciparum were evaluated in the study. Sample AA was lyophilized, whilst samples BB, CC and DD were liquid/frozen preparations. The candidate standards were tested by each laboratory at a range of dilutions in four independent assays, using both qualitative and quantitative NAT-based assays. The results were collated and analysed statistically. Results Twenty sets of data were returned from the participating laboratories and used to determine the mean P. falciparum DNA content for each sample. The mean log10 "equivalents"/ml were 8.51 for sample AA, 8.45 for sample BB, 8.35 for sample CC, and 5.51 for sample DD. The freeze-dried preparation AA, was examined by accelerated thermal degradation studies and found to be highly stable. Conclusion On the basis of the collaborative study, the freeze-dried material, AA (NIBSC code No. 04/176) was established as the 1st WHO International Standard for P. falciparum DNA NAT-based assays and has been assigned a potency of 109 International Units (IU) per ml. Each vial contains 5 × 108 IU, equivalent to 0.5 ml of material after reconstitution. PMID:18652656

  19. A new landscape metric for the identification of terraced sites: The Slope Local Length of Auto-Correlation (SLLAC)

    NASA Astrophysics Data System (ADS)

    Sofia, Giulia; Marinello, Francesco; Tarolli, Paolo

    2014-10-01

    This work presents the potential for high-resolution remote sensing data (LiDAR digital terrain models) to determine the spatial heterogeneity of terraced landscapes. The study objective is achieved through the identification of a new parameter that distinguishes this unique landscape form from more natural land formations. The morphological indicator proposed is called the Slope Local Length of Auto-Correlation (SLLAC), and it is derived from the local analysis of slope self-similarity. The SLACC is obtained over two steps: (i) calculating the correlation between a slope patch and a defined surrounding area and (ii) identifying the characteristic length of correlation for each neighbourhood. The SLLAC map texture can be measured using a surface metrology metric called the second derivative of peaks, or Spc. For the present study, we tested the algorithm for two types of landscapes: a Mediterranean and an Alpine one. The research method involved an examination of both real LiDAR DTMs and simulated ones, in which it was possible to control terrace shapes and the percentage of area covered by terraces. The results indicate that SLLAC maps exhibit a random aspect for natural surfaces. In contrast, terraced landscapes demonstrate a higher degree of order, and this behaviour is independent of the morphological context and terracing system. The outcomes of this work also prove that Spc values decrease as the area of terraced surfaces increases within the investigated region: the Spc for terraced areas is significantly different from the Spc of a natural landscape. In areas of smooth natural morphology, the Spc identifies terraced areas with a 20% minimum height range covered in terraces. In contrast, in areas of steep morphologies and vertical cliffs, the algorithm performs well when terraces cover at least 50% of the investigated surface. Given the increasing importance of terraced landscapes, the proposed procedure offers a significant and promising tool for the

  20. Embryonic development of chicken (Gallus Gallus Domesticus) from 1st to 19th day-ectodermal structures.

    PubMed

    Toledo Fonseca, Erika; De Oliveira Silva, Fernanda Menezes; Alcântara, Dayane; Carvalho Cardoso, Rafael; Luís Franciolli, André; Sarmento, Carlos Alberto Palmeira; Fratini, Paula; José Piantino Ferreira, Antônio; Miglino, Maria Angélica

    2013-12-01

    Birds occupy a prominent place in the Brazilian economy not only in the poultry industry but also as an animal model in many areas of scientific research. Thus the aim of this study was to provide a description of macro and microscopic aspects of the ectoderm-derived structures in chicken embryos / fetuses poultry (Gallus gallus domesticus) from 1st to 19th day of incubation. 40 fertilized eggs, from a strain of domestic chickens, with an incubation period of 2-19 days were subjected to macroscopic description, biometrics, light, and scanning microscopy. All changes observed during the development were described. The nervous system, skin and appendages and organs related to vision and hearing began to be identified, both macro and microscopically, from the second day of incubation. The vesicles from the primitive central nervous system-forebrain, midbrain, and hindbrain-were identified on the third day of incubation. On the sixth day of incubation, there was a clear vascularization of the skin. The optic vesicle was first observed fourth day of development and on the fifth day there was the beginning of the lens formation. Although embryonic development is influenced by animal line as well as external factors such as incubation temperature, this paper provides a chronological description for chicken (Gallus gallus domesticus) during its embryonic development.

  1. Stem Cell Gene Therapy for Fanconi Anemia: Report from the 1st International Fanconi Anemia Gene Therapy Working Group Meeting

    PubMed Central

    Tolar, Jakub; Adair, Jennifer E; Antoniou, Michael; Bartholomae, Cynthia C; Becker, Pamela S; Blazar, Bruce R; Bueren, Juan; Carroll, Thomas; Cavazzana-Calvo, Marina; Clapp, D Wade; Dalgleish, Robert; Galy, Anne; Gaspar, H Bobby; Hanenberg, Helmut; Von Kalle, Christof; Kiem, Hans-Peter; Lindeman, Dirk; Naldini, Luigi; Navarro, Susana; Renella, Raffaele; Rio, Paula; Sevilla, Julián; Schmidt, Manfred; Verhoeyen, Els; Wagner, John E; Williams, David A; Thrasher, Adrian J

    2011-01-01

    Survival rates after allogeneic hematopoietic cell transplantation (HCT) for Fanconi anemia (FA) have increased dramatically since 2000. However, the use of autologous stem cell gene therapy, whereby the patient's own blood stem cells are modified to express the wild-type gene product, could potentially avoid the early and late complications of allogeneic HCT. Over the last decades, gene therapy has experienced a high degree of optimism interrupted by periods of diminished expectation. Optimism stems from recent examples of successful gene correction in several congenital immunodeficiencies, whereas diminished expectations come from the realization that gene therapy will not be free of side effects. The goal of the 1st International Fanconi Anemia Gene Therapy Working Group Meeting was to determine the optimal strategy for moving stem cell gene therapy into clinical trials for individuals with FA. To this end, key investigators examined vector design, transduction method, criteria for large-scale clinical-grade vector manufacture, hematopoietic cell preparation, and eligibility criteria for FA patients most likely to benefit. The report summarizes the roadmap for the development of gene therapy for FA. PMID:21540837

  2. Case Study of Severe Lightning Activity Prior to and During the Outbreak of the June 1st Greenbelt Tornado

    NASA Astrophysics Data System (ADS)

    Barnum, B. H.; Badesha, S.; Shishineh, A.; Adams, N. H.

    2012-12-01

    Surges in lightning activity have been known to be associated with the outbreak of tornado activity. We present a case study of a tornado that touched down near Greenbelt Maryland during the evening of June 1st 2012. Preceding the tornado touchdown, two single point lightning detection systems, a Boltek LD-250 and Vaisala SA20, recorded very high lightning activity rates. An electric field mill (EFM) was also making measurements and recorded large, rapid amplitude oscillations in the vertical electric fields. These electric field oscillations quickly subsided after the initial tornado touchdown. The lightning activity also generated significant RF interference in the S-band dish antenna operated at the Applied Physics Laboratory. It was somewhat surprising that the lightning activity produced enough radiation at these frequencies to cause measured levels of interference which could potentially impair satellite communications. Our interpretation of the EFM data is that intensive vertical forcing and rotation in the thunderstorm during the tornado formation caused the observed rapid electric field oscillations. At the same time, the vertical mixing in the storm caused a surge in lightning activity rates recorded by the Boltek and Vaisala sensors. Following the tornado touchdown, there was a rapid decrease in the lightning rates from the sensors. The EFM oscillations also abruptly ceased and went to a more normal slow-varying pattern typically observed during other thunderstorms without associated tornado activity. It is suggested that a network of field mills could provide realtime warning of imminent tornado activity.

  3. 1st Quarter Transportation Report FY 2015: Radioactive Waste Shipments to and from the Nevada National Security Site (NNSS)

    SciTech Connect

    Gregory, Louis

    2015-02-20

    This report satisfies the U.S. Department of Energy (DOE), National Nuclear Security Administration Nevada Field Office (NNSA/NFO) commitment to prepare a quarterly summary report of radioactive waste shipments to and from the Nevada National Security Site (NNSS) Radioactive Waste Management Complex (RWMC) at Area 5. There were no shipments sent for offsite treatment and returned to the NNSS this quarter. This report summarizes the 1st quarter of Fiscal Year (FY) 2015 low-level radioactive waste (LLW) and mixed low-level radioactive waste (MLLW) shipments. Tabular summaries are provided which include the following: Sources of and carriers for LLW and MLLW shipments to and from the NNSS; Number and external volume of LLW and MLLW shipments; Highway routes used by carriers; and Incident/accident data applicable to LLW and MLLW shipments. In this report shipments are accounted for upon arrival at the NNSS, while disposal volumes are accounted for upon waste burial. The disposal volumes presented in this report include minor volumes of non-radioactive classified waste/material that were approved for disposal (non-radioactive classified or nonradioactive classified hazardous). Volume reports showing cubic feet generated using the Low-Level Waste Information System may vary slightly due to rounding conventions for volumetric conversions from cubic meters to cubic feet.

  4. 1st International Conference on Panic Attacks: diversity of theories and treatments. september 5-8, 2003, London.

    PubMed

    Perry, David

    2004-04-01

    The 1st International Conference on Psychophysiology of Panic Attacks focused on the diversity of treatments and theories in this complex condition. Experimental research topics were featured, as well as treatment strategies, case studies and patient perspectives. The conference aimed to create a strong multi-cultural emphasis through international, interdisciplinary and patient-professional interaction. The experimental techniques of lactate provocation of panic, carbon dioxide provocation, respiratory measures and cholecystokinin tetrapeptide infusion were used in various ongoing studies aimed at investigating familial markers, protocols for inducing panic in subjects (including opioid-receptor blockade), brain stem mechanisms involved in mediating anxiety and correlation of respiratory variability with panic severity and treatment outcome. Internet-based questionnaire surveys of panic attack (PA) in subjects that had been sexually abused and of subjective feelings about PAs in patients undergoing fertility treatment were presented, as was a survey of panic epidemiology in Iranian students. Some novel treatment modes were discussed, including non-verbal imagery and art therapy and a telephone-conferencing delivery of cognitive-behavioural therapy. Several case studies were used to illustrate treatments and a personal account of panic disorder combined some time after onset with post-traumatic stress disorder highlighted the different responses of the two disorders to psychotherapies.

  5. A collaborative study to establish the 1st WHO International Standard for human cytomegalovirus for nucleic acid amplification technology.

    PubMed

    Fryer, Jacqueline F; Heath, Alan B; Minor, Philip D

    2016-07-01

    Variability in the performance of nucleic acid amplification technology (NAT)-based assays presents a significant problem in the diagnosis and management of human cytomegalovirus (HCMV) infections. Here we describe a collaborative study to evaluate the suitability of candidate reference materials to harmonize HCMV viral load measurements in a wide range of NAT assays. Candidate materials comprised lyophilized Merlin virus, liquid Merlin virus, liquid AD169 virus, and purified HCMV Merlin DNA cloned into a bacterial artificial chromosome. Variability in the laboratory mean HCMV concentrations determined for virus samples across the different assays was 2 log10. Variability for the purified DNA sample was higher (>3 log10). The agreement between laboratories was markedly improved when the potencies of the liquid virus samples were expressed relative to the lyophilized virus candidate. In contrast, the agreement between laboratories for the purified DNA sample was not improved. Results indicated the suitability of the lyophilized Merlin virus preparation as the 1st WHO International Standard for HCMV for NAT. It was established in October 2010, with an assigned potency of 5 × 10(6) International Units (IU) (NIBSC code 09/162). It is intended to be used to calibrate secondary references, used in HCMV NAT assays, in IU.

  6. Synthesis of nanomagnetic fluids and their UV spectrophotometric response with aliphatic organic acids and 1st tier dendrimers

    NASA Astrophysics Data System (ADS)

    Pandya, Shivani R.; Singh, Man

    2016-04-01

    Synthesis of Magnetic nanoparticles were made using coprecipitation method on mixing Fe+3 and Fe+2 in 2:1 ratio with aqueous 8M NaOH which on heating at 90°C for 2 h has yielded 85% magnetic (Fe3O4) nanoparticles (MNPs), characterized by XRD, VSM, SEM, and HR-TEM. The formic acid (FA), oxalic acid (OA) and citric acid (CA), the series of aliphatic organic acids along with Trimesoyl 1, 3, 5 tridimethyl malonate (TTDMM), trimesoyl 1, 3, 5 tridiethyl malonate (TTDEM), trimesoyl 1, 3, 5 tridipropyl malonate (TTDPM), trimesoyl 1, 3, 5 tridibutyl malonate (TTDBM) and trimesoyl 1, 3, 5 tridihexyl malonate (TTDHM) 1st tier dendrimers were used separately for preparing nanomagnetic fluid. From 25 to 150 µM MNPs at an interval of 25 µM were dispersed in 150 µM of acids and dendrimers separately with DMSO. UV-VIS spectrophotometry showed a maximum MNPs dispersion with TTDMM against others and found to be most stable nanomagnetic fluid on account of capping type mechanism of acids.

  7. Child gender and weight status moderate the relation of maternal feeding practices to body esteem in 1st grade children.

    PubMed

    Shriver, Lenka H; Hubbs-Tait, Laura; Harrist, Amanda W; Topham, Glade; Page, Melanie

    2015-06-01

    Prevention of body dissatisfaction development is critical for minimizing adverse effects of poor body esteem on eating behaviors, self-esteem, and overall health. Research has examined body esteem and its correlates largely in pre-adolescents and adolescents; however, important questions remain about factors influencing body esteem of younger children. The main purpose of this study was to test moderation by children's gender and weight status of the relation of maternal controlling feeding practices to 1st graders' body esteem. The Body Esteem Scale (BES) and anthropometric measurements were completed during one-on-one child interviews at school. Mothers completed the Child Feeding Questionnaire (restriction, monitoring, concern, self-assessed maternal weight). A total of 410 mother/child dyads (202 girls) participated. Percent of children classified as overweight (BMI-for-age ≥85th) was: girls - 29%; boys - 27%. Gender moderated the relation between restriction and body esteem (β = -.140, p = .05), with maternal restriction predicting body esteem in girls but not boys. The hypothesized three-way interaction among gender, child weight status, and monitoring was confirmed. Monitoring was significantly inversely related to body esteem only for overweight/obese girls (b = -1.630). The moderating influence of gender or gender and weight status on the link between maternal feeding practices and body esteem suggests the importance of body esteem interventions for girls as early as first grade.

  8. Moving beyond the Lone Scientist: Helping 1st-Grade Students Appreciate the Social Context of Scientific Work Using Stories about Scientists

    ERIC Educational Resources Information Center

    Sharkawy, Azza

    2009-01-01

    While several studies have documented young children's (K-2) stereotypic views of scientists and scientific work, few have examined students' views of the social nature of scientific work and the strategies effective in broadening these views. The purpose of this study is to examine how stories about scientists influence 1st-grade students' views…

  9. Diagnostic Online Assessment of Basic IT Skills in 1st-Year Undergraduates in the Medical Sciences Division, University of Oxford

    ERIC Educational Resources Information Center

    Sieber, Vivien

    2009-01-01

    Attitude, experience and competence (broadly covered by the European Computer Driving Licence syllabus) in information technology (IT) were assessed in 846 1st-year Medical Sciences Division undergraduates (2003-06) at the start of their first term. Online assessments delivered during induction workshops were presented as an opportunity for…

  10. The Impact of Gender-Fair versus Gender-Stereotyped Basal Readers on 1st-Grade Children's Gender Stereotypes: A Natural Experiment

    ERIC Educational Resources Information Center

    Karniol, Rachel; Gal-Disegni, Michal

    2009-01-01

    Israeli 1st-grade children in two different schools in the same neighborhood who were using either a gender-stereotyped or a gender-fair basal reader were asked to judge for a series of female-stereotyped, male-stereotyped, and gender-neutral activities whether they were characteristic of females, of males, or of both. Children using the…

  11. Brood parasitism correlates with the strength of spatial autocorrelation of life history and defensive traits in Magpies.

    PubMed

    Soler, Juan J; Martín-Gálvez, David; de Neve, Liesbeth; Soler, Manuel

    2013-06-01

    Environmental characteristics of neighboring locations are generally more similar than those of distant locations. Selection pressures due to parasitism and other environmental conditions shape life history traits of hosts; thus, the probability of parasitism should be associated with the strength of spatial autocorrelation in life history and defensive traits of their hosts. Here we test this hypothesis in three different subpopulations of Magpie (Pica pica) parasitized by the Great Spotted Cuckoo (Clamator glandarius) during three breeding seasons. In some of the years and study plots, we found evidence of positive spatial autocorrelations for clutch size and parasitism rate, but not for laying date. As predicted, brood parasitism was associated with the strength of these spatial autocorrelations. Magpies that bred close to each other in areas of high risk of parasitism responded similarly to experimental parasitic eggs. Moreover, an elevated risk of parasitism eliminated the spatial autocorrelation for clutch size, which became randomly distributed. We discuss possible mechanisms explaining these associations, which may have important consequences for estimating evolutionary responses of hosts to parasitic infections and, therefore, for epidemiological, ecological, and evolutionary studies of host-parasite relationships.

  12. Very long baseline interferometry and observations of gravitational lenses using intensity fluctuations: an analysis based on intensity autocorrelation

    NASA Astrophysics Data System (ADS)

    Borra, Ermanno F.

    2014-05-01

    A novel interferometric technique that uses the spectrum of the current fluctuations of a quadratic detector, a type of detector commonly used in Astronomy, has recently been introduced. It has major advantages with respect to classical interferometry. It can be used to observe gravitational lenses that cannot be detected with standard techniques. It can be used to carry out very long baseline interferometry. Although the original theoretical analysis, that uses wave interaction effects, is rigorous, it is not easy to understand. The present article therefore carries out a simpler analysis, using the autocorrelation of intensity fluctuations, which is easier to understand. It is based on published experiments that were carried out to validate the original theory. The autocorrelation analysis also validates simple numerical techniques, based on the autocorrelation, to model the angular intensity distribution of a source. The autocorrelation technique also allows a much simpler detection of the signal. In practice, the gravitational lens applications are the ones that can readily be done with presently available telescopes. We describe a practical example that shows that presently available VLBI radio-astronomical data can be used to observe microlensisng and millilensing in macrolensed Quasars. They may give information on the dark matter substructures in the lensing galaxies.

  13. Generalizability Assessment of Autocorrelated Direct Observation Data: The Applicability of the Tiao-Tan Method and Alternative.

    ERIC Educational Resources Information Center

    Suen, Hoi K.; And Others

    The applicability is explored of the Bayesian random-effect analysis of variance (ANOVA) model developed by G. C. Tiao and W. Y. Tan (1966) and a method suggested by H. K. Suen and P. S. Lee (1987) for the generalizability analysis of autocorrelated data. According to Tiao and Tan, if time series data could be described as a first-order…

  14. Autocorrelations of stellar light and mass at z˜ 0 and ˜1: from SDSS to DEEP2

    NASA Astrophysics Data System (ADS)

    Li, Cheng; White, Simon D. M.; Chen, Yanmei; Coil, Alison L.; Davis, Marc; De Lucia, Gabriella; Guo, Qi; Jing, Y. P.; Kauffmann, Guinevere; Willmer, Christopher N. A.; Zhang, Wei

    2012-01-01

    We present measurements of projected autocorrelation functions wp(rp) for the stellar mass of galaxies and for their light in the U, B and V bands, using data from the third data release of the DEEP2 Galaxy Redshift Survey and the final data release of the Sloan Digital Sky Survey (SDSS). We investigate the clustering bias of stellar mass and light by comparing these to projected autocorrelations of dark matter estimated from the Millennium Simulations (MS) at z= 1 and 0.07, the median redshifts of our galaxy samples. All of the autocorrelation and bias functions show systematic trends with spatial scale and waveband which are impressively similar at the two redshifts. This shows that the well-established environmental dependence of stellar populations in the local Universe is already in place at z= 1. The recent MS-based galaxy formation simulation of Guo et al. reproduces the scale-dependent clustering of luminosity to an accuracy better than 30 per cent in all bands and at both redshifts, but substantially overpredicts mass autocorrelations at separations below about 2 Mpc. Further comparison of the shapes of our stellar mass bias functions with those predicted by the model suggests that both the SDSS and DEEP2 data prefer a fluctuation amplitude of σ8˜ 0.8 rather than the σ8= 0.9 assumed by the MS.

  15. Field test comparison of an autocorrelation technique for determining grain size using a digital 'beachball' camera versus traditional methods

    USGS Publications Warehouse

    Barnard, P.L.; Rubin, D.M.; Harney, J.; Mustain, N.

    2007-01-01

    This extensive field test of an autocorrelation technique for determining grain size from digital images was conducted using a digital bed-sediment camera, or 'beachball' camera. Using 205 sediment samples and >1200 images from a variety of beaches on the west coast of the US, grain size ranging from sand to granules was measured from field samples using both the autocorrelation technique developed by Rubin [Rubin, D.M., 2004. A simple autocorrelation algorithm for determining grain size from digital images of sediment. Journal of Sedimentary Research, 74(1): 160-165.] and traditional methods (i.e. settling tube analysis, sieving, and point counts). To test the accuracy of the digital-image grain size algorithm, we compared results with manual point counts of an extensive image data set in the Santa Barbara littoral cell. Grain sizes calculated using the autocorrelation algorithm were highly correlated with the point counts of the same images (r2 = 0.93; n = 79) and had an error of only 1%. Comparisons of calculated grain sizes and grain sizes measured from grab samples demonstrated that the autocorrelation technique works well on high-energy dissipative beaches with well-sorted sediment such as in the Pacific Northwest (r2 ??? 0.92; n = 115). On less dissipative, more poorly sorted beaches such as Ocean Beach in San Francisco, results were not as good (r2 ??? 0.70; n = 67; within 3% accuracy). Because the algorithm works well compared with point counts of the same image, the poorer correlation with grab samples must be a result of actual spatial and vertical variability of sediment in the field; closer agreement between grain size in the images and grain size of grab samples can be achieved by increasing the sampling volume of the images (taking more images, distributed over a volume comparable to that of a grab sample). In all field tests the autocorrelation method was able to predict the mean and median grain size with ???96% accuracy, which is more than

  16. Current practice of epidemiology in Africa: highlights of the 3rd conference of the African epidemiological association and 1st conference of the Cameroon society of epidemiology, Yaoundé, Cameroon, 2014.

    PubMed

    Nkwescheu, Armand Seraphin; Fokam, Joseph; Tchendjou, Patrice; Nji, Akindeh; Ngouakam, Hermann; Andre, Bita Fouda; Joelle, Sobngwi; Uzochukwu, Benjamin; Akinroye, Kingsley; Mbacham, Wilfred; Colizzi, Vittorio; Leke, Rose; Victora, Cesar

    2015-01-01

    As the study of disease occurrence and health indicators in human populations, Epidemiology is a dynamic field that evolves with time and geographical context. In order to update African health workers on current epidemiological practices and to draw awareness of early career epidemiologists on concepts and opportunities in the field, the 3(rd) African Epidemiology Association and the 1st Cameroon Society of Epidemiology Conference was organized in June 2-6, 2014 at the Yaoundé Mont Febe Hotel, in Cameroon. Under the theme«Practice of Epidemiology in Africa: Stakes, Challenges and Perspectives», the conference attracted close to five hundred guest and participants from all continents. The two main programs were the pre-conference course for capacity building of African Early Career epidemiologists, and the conference itself, providing a forum for scientific exchanges on recent epidemiological concepts, encouraging the use of epidemiological methods in studying large disease burden and neglected tropical diseases; and highlighting existing opportunities.

  17. Cognitive-based approach in teaching 1st year Physics for Life Sciences, including Atmospheric Physics and Climate Change components

    NASA Astrophysics Data System (ADS)

    Petelina, S. V.

    2009-12-01

    Most 1st year students who take the service course in Physics - Physics for Life Sciences - in Australia encounter numerous problems caused by such factors as no previous experience with this subject; general perception that Physics is hard and only very gifted people are able to understand it; lack of knowledge of elementary mathematics; difficulties encountered by lecturers in teaching university level Physics to a class of nearly 200 students with no prior experience, diverse and sometime disadvantageous backgrounds, different majoring areas, and different learning abilities. As a result, many students either drop, or fail the subject. In addition, many of those who pass develop a huge dislike towards Physics, consider the whole experience as time wasted, and spread this opinion among their peers and friends. The above issues were addressed by introducing numerous changes to the curriculum and modifying strategies and approaches in teaching Physics for Life Sciences. Instead of a conventional approach - teaching Physics from simple to complicated, topic after topic, the students were placed in the world of Physics in the same way as a newborn child is introduced to this world - everything is seen all the time and everywhere. That created a unique environment where a bigger picture and all details were always present and interrelated. Numerous concepts of classical and modern physics were discussed, compared, and interconnected all the time with “Light” being a key component. Our primary field of research is Atmospheric Physics, in particular studying the atmospheric composition and structure using various satellite and ground-based data. With this expertise and also inspired by an increasing importance of training a scientifically educated generation who understands the challenges of the modern society and responsibilities that come with wealth, a new section on environmental physics has been developed. It included atmospheric processes and the greenhouse

  18. Establishment of the 1st World Health Organization international standards for human papillomavirus type 16 DNA and type 18 DNA.

    PubMed

    Wilkinson, Dianna E; Baylis, Sally A; Padley, David; Heath, Alan B; Ferguson, Morag; Pagliusi, Sonia R; Quint, Wim G; Wheeler, Cosette M

    2010-06-15

    A World Health Organization collaborative study was conducted to evaluate candidate international standards for human papillomavirus (HPV) Type 16 DNA (NIBSC code 06/202) and HPV Type 18 DNA (NIBSC code 06/206) for use in the amplification and detection steps of nucleic acid-based assays. The freeze-dried candidate international standards were prepared from bulk preparations of cloned plasmid containing full-length HPV-16 or HPV-18 genomic DNA. Nineteen laboratories from 13 countries participated in the study using a variety of commercial and in-house quantitative and qualitative assays. The data presented here indicate that, upon freeze-drying, there is no significant loss in potency for the candidate HPV-18 DNA and a slight loss in potency for the candidate HPV-16 DNA; although this is likely not scientifically relevant when assay precision is considered. In general, the individual laboratory mean estimates for each study sample were grouped +/- approximately 2 log(10) around the theoretical HPV DNA concentration of the reconstituted ampoule (1 x 10(7) HPV genome equivalents/mL). The agreement between laboratories is improved when potencies are made relative to the candidate international standards, demonstrating their utility in harmonizing amplification and detection steps of HPV-16 and -18 DNA assays. Degradation studies indicate that the candidate international standards are extremely stable and suitable for long-term use. Based on these findings, the candidate standards were established as the 1st WHO international standards for HPV-16 DNA and HPV-18 DNA, each with a potency of 5 x 10(6) international units (IU) per ampoule or 1 x 10(7) IU mL(-1) when reconstituted as directed.

  19. Residual effects of TMOF-Bti formulations against 1st instar Aedes aegypti Linnaeus larvae outside laboratory

    PubMed Central

    Saiful, AN; Lau, MS; Sulaiman, S; Hidayatulfathi, O

    2012-01-01

    Objective To evaluate the effectiveness and residual effects of trypsin modulating oostatic factor-Bacillus thuringiensis israeliensis (TMOF-Bti) formulations against Aedes aegypti (Ae. aegypti) (L.) larvae at UKM Campus Kuala Lumpur. Methods Twenty first instar Ae. aegypti larvae were added in each bucket containing 4 L of water supplied with crushed dried leaf powder as their source of food. Combination of TMOF-Bti in rice husk formulation with the following weights viz 10, 25, 50 and 100 mg, respectively in duplicate was distributed in the buckets; while TMOF-Bti in wettable powder formulation each weighing viz 2, 5, 10 and 20 mg, respectively in duplicate was also placed in the buckets. The control buckets run in duplicate with 4 L of water and 20 first instar Ae. aegypti larvae. All buckets were covered with mosquito netting. Larval mortality was recorded after 24 hours and weekly for five weeks. A new batch of 20 1st instar larvae Ae. aegypti was introduced into each bucket weekly without additional TMOF-Bti rice husk formulation or wettable powder. The experiment was repeated for four times. Results The result of the study showed that all formulations were very effective on the first two weeks by giving 100% larval mortality for all concentrations applied. The TMOF (2%) + Bti (2%) had a good residual effect until the end of 3rd week, TMOF (4%) + Bti (4%) until 4th week, wettable powder TMOF (20%) + Bti (20%) until the third week. Conclusions From the results it can be concluded that the TMOF-Bti formulations can be utilized in dengue vector control. PMID:23569922

  20. New approaches for improving the production of the 1st and 2nd generation ethanol by yeast.

    PubMed

    Kurylenko, Olena; Semkiv, Marta; Ruchala, Justyna; Hryniv, Orest; Kshanovska, Barbara; Abbas, Charles; Dmytruk, Kostyantyn; Sibirny, Andriy

    2016-01-01

    Increase in the production of 1st generation ethanol from glucose is possible by the reduction in the production of ethanol co-products, especially biomass. We have developed a method to reduce biomass accumulation of Saccharomyces cerevisiae by the manipulation of the intracellular ATP level due to overexpression of genes of alkaline phosphatase, apyrase or enzymes involved in futile cycles. The strains constructed accumulated up to 10% more ethanol on a cornmeal hydrolysate medium. Similar increase in ethanol accumulation was observed in the mutants resistant to the toxic inhibitors of glycolysis like 3-bromopyruvate and others. Substantial increase in fuel ethanol production will be obtained by the development of new strains of yeasts that ferment sugars of the abundant lignocellulosic feedstocks, especially xylose, a pentose sugar. We have found that xylose can be fermented under elevated temperatures by the thermotolerant yeast, Hansenula polymorpha. We combined protein engineering of the gene coding for xylose reductase (XYL1) along with overexpression of the other two genes responsible for xylose metabolism in yeast (XYL2, XYL3) and the deletion of the global transcriptional activator CAT8, with the selection of mutants defective in utilizing ethanol as a carbon source using the anticancer drug, 3-bromopyruvate. Resulted strains accumulated 20-25 times more ethanol from xylose at the elevated temperature of 45°C with up to 12.5 g L(-1) produced. Increase in ethanol yield and productivity from xylose was also achieved by overexpression of genes coding for the peroxisomal enzymes: transketolase (DAS1) and transaldolase (TAL2), and deletion of the ATG13 gene.

  1. Time-autocorrelated two-photon counting technique for time-resolved fluorescence measurements

    NASA Astrophysics Data System (ADS)

    Borst, Walter L.; Liu, Lin-I.

    1999-01-01

    We describe a new instrumental technique for the excitation, acquisition, and analysis of fluorescence decays from a variety of substances, in the present case plastic scintillators. The fluorescence is excited by β particles from a radioactive source (100 μCi Sr-90). A random photon from the resulting fluorescence decay provides a trigger pulse to start a time-to-amplitude converter (TAC), while another random photon from the same β-excitation event provides the stop pulse. The optical components and geometry for detecting these two photons, i.e., the two photomultipliers (PMT), the filters, and the pulse counting system, are identical. As a consequence, the measured fluorescence signal is the autocorrelation function of the fluorescence decay from the sample. A delay line of 50 ns is inserted between the "stop" signal PMT and the TAC so that those "stop" pulses which arrive before "start pulses" also are recorded. Thus the acquired fluorescence signal versus time is symmetric about the delay time and contains twice as many counts as without delay. We call the new technique the "time-autocorrelated two-photon counting technique" (TATPC) in distinction to the conventional "time-correlated single-photon counting technique" (TCSPC). We compared both techniques with the same equipment and scintillators, where in the TCSPC case, a β particle is used for the start of the TAC instead of a random photon in the TATPC technique. We find that under similar experimental circumstances, the signal count rate with TATPC is about 50 times larger than with TCSPC. The new method is well suited for obtaining fluorescence decay times from plastic scintillators, which we use in this article to exemplify the technique. More generally, β-particle excitation in combination with TATPC should prove useful for materials with high energy levels or band gaps, which cannot be excited with pulsed lasers in the visible region. The length of our excitation pulse is less than 20 ps and is

  2. Characterization of Forested Landscapes From Remotely Sensed Data Using Fractals and Spatial Autocorrelation

    NASA Technical Reports Server (NTRS)

    Al-Hamdan, Mohammad Z.; Cruise, James F.; Rickman, Douglas L.; Quattrochi, Dale A.

    2007-01-01

    The characterization of forested areas is frequently required in resource management practice. Passive remotely sensed data, which are much more accessible and cost effective than are active data, have rarely, if ever, been used to characterize forest structure directly, but rather they usually focus on the estimation of indirect measurement of biomass or canopy coverage. In this study, some spatial analysis techniques are presented that might be employed with Landsat TM data to analyze forest structure characteristics. A case study is presented wherein fractal dimensions, along with a simple spatial autocorrelation technique (Moran s I), were related to stand density parameters of the Oakmulgee National Forest located in the southeastern United States (Alabama). The results of the case study presented herein have shown that as the percentage of smaller diameter trees becomes greater, and particularly if it exceeds 50%, then the canopy image obtained from Landsat TM data becomes sufficiently homogeneous so that the spatial indices reach their lower limits and thus are no longer determinative. It also appears, at least for the Oakmulgee forest, that the relationships between the spatial indices and forest class percentages within the boundaries can reasonably be considered linear. The linear relationship is much more pronounced in the sawtimber and saplings cases than in samples dominated by medium sized trees (poletimber). In addition, it also appears that, at least for the Oakmulgee forest, the relationships between the spatial indices and forest species groups (Hardwood and Softwood) percentages can reasonably be considered linear. The linear relationship is more pronounced in the forest species groups cases than in the forest classes cases. These results appear to indicate that both fractal dimensions and spatial autocorrelation indices hold promise as means of estimating forest stand characteristics from remotely sensed images. However, additional work is

  3. The application of local measures of spatial autocorrelation for describing pattern in north Australian landscapes.

    PubMed

    Pearson, Diane M

    2002-01-01

    This paper tests the use of a spatial analysis technique, based on the calculation of local spatial autocorrelation, as a possible approach for modelling and quantifying structure in northern Australian savanna landscapes. Unlike many landscapes in the world, northern Australian savanna landscapes appear on the surface to be intact. They have not experienced the same large-scale land clearance and intensive land management as other landscapes across Australia. Despite this, natural resource managers are beginning to notice that processes are breaking down and declines in species are becoming more evident. With future declines of species looking more imminent it is particularly important that models are available that can help to assess landscape health, and quantify any structural change that takes place. GIS and landscape ecology provide a useful way of describing landscapes both spatially and temporally and have proved to be particularly useful for understanding vegetation structure or pattern in landscapes across the world. There are many measures that examine spatial structure in the landscape and most of these are now available in a GIS environment (e.g. FRAGSTATS* ARC, r.le, and Patch Analyst). All these methods depend on a landscape described in terms of patches, corridors and matrix. However, since landscapes in northern Australia appear to be relatively intact they tend to exist as surfaces of continuous variation rather than in clearly defined homogeneous units. As a result they cannot be easily described using entity-based models requiring patches and other essentially cartographic approaches. This means that more appropriate methods need to be developed and explored. The approach examined in this paper enables clustering and local pattern in the data to be identified and forms a generic method for conceptualising the landscape structure where patches are not obvious and where boundaries between landscape features are difficult to determine. Two sites

  4. Moral judgment and its relation to second-order theory of mind.

    PubMed

    Fu, Genyue; Xiao, Wen S; Killen, Melanie; Lee, Kang

    2014-08-01

    Recent research indicates that moral judgment and 1st-order theory of mind abilities are related. What is not known, however, is how 2nd-order theory of mind is related to moral judgment. In the present study, we extended previous findings by administering a morally relevant theory of mind task (an accidental transgressor) to 4- to 7-year-old Chinese children (N = 79) and analyzing connections with 2nd-order theory of mind understanding. Using hierarchical multiple regression analyses, we found that above and beyond age, children's 1st-order theory of mind and 2nd-order theory of mind each significantly and uniquely contributed to children's moral evaluations of the intention in the accidental transgression. These findings highlight the important roles that 1st- and 2nd-order theory of mind play in leading children to make appropriate moral judgments based on an actor's intention in a social situation.

  5. High-Responsivity Graphene-Boron Nitride Photodetector and Autocorrelator in a Silicon Photonic Integrated Circuit.

    PubMed

    Shiue, Ren-Jye; Gao, Yuanda; Wang, Yifei; Peng, Cheng; Robertson, Alexander D; Efetov, Dmitri K; Assefa, Solomon; Koppens, Frank H L; Hone, James; Englund, Dirk

    2015-11-11

    Graphene and other two-dimensional (2D) materials have emerged as promising materials for broadband and ultrafast photodetection and optical modulation. These optoelectronic capabilities can augment complementary metal-oxide-semiconductor (CMOS) devices for high-speed and low-power optical interconnects. Here, we demonstrate an on-chip ultrafast photodetector based on a two-dimensional heterostructure consisting of high-quality graphene encapsulated in hexagonal boron nitride. Coupled to the optical mode of a silicon waveguide, this 2D heterostructure-based photodetector exhibits a maximum responsivity of 0.36 A/W and high-speed operation with a 3 dB cutoff at 42 GHz. From photocurrent measurements as a function of the top-gate and source-drain voltages, we conclude that the photoresponse is consistent with hot electron mediated effects. At moderate peak powers above 50 mW, we observe a saturating photocurrent consistent with the mechanisms of electron-phonon supercollision cooling. This nonlinear photoresponse enables optical on-chip autocorrelation measurements with picosecond-scale timing resolution and exceptionally low peak powers.

  6. Ultrasound modulated light blood flow measurement using intensity autocorrelation function: a Monte-Carlo simulation

    NASA Astrophysics Data System (ADS)

    Tsalach, A.; Metzger, Y.; Breskin, I.; Zeitak, R.; Shechter, R.

    2014-03-01

    Development of techniques for continuous measurement of regional blood flow, and in particular cerebral blood flow (CBF), is essential for monitoring critical care patients. Recently, a novel technique, based on ultrasound modulation of light was developed for non-invasive, continuous CBF monitoring (termed ultrasound-tagged light (UTL or UT-NIRS)), and shown to correlate with readings of 133 Xe SPECT1 and laser Doppler2. Coherent light is introduced into the tissue concurrently with an Ultrasound (US) field. Displacement of scattering centers within the sampled volume induced by Brownian motion, blood flow and the US field affects the photons' temporal correlation. Hence, the temporal fluctuations of the obtained speckle pattern provide dynamic information about the blood flow. We developed a comprehensive simulation, combining the effects of Brownian motion, US and flow on the obtained speckle pattern. Photons trajectories within the tissue are generated using a Monte-Carlo based model. Then, the temporal changes in the optical path due to displacement of scattering centers are determined, and the corresponding interference pattern over time is derived. Finally, the light intensity autocorrelation function of a single speckle is calculated, from which the tissue decorrelation time is determined. The simulation's results are compared with in-vitro experiments, using a digital correlator, demonstrating decorrelation time prediction within the 95% confidence interval. This model may assist in the development of optical based methods for blood flow measurements and particularly, in methods using the acousto-optic effect.

  7. Shear-stress relaxation and ensemble transformation of shear-stress autocorrelation functions

    NASA Astrophysics Data System (ADS)

    Wittmer, J. P.; Xu, H.; Baschnagel, J.

    2015-02-01

    We revisit the relation between the shear-stress relaxation modulus G (t ) , computed at finite shear strain 0 <γ ≪1 , and the shear-stress autocorrelation functions C(t ) | γ and C(t ) | τ computed, respectively, at imposed strain γ and mean stress τ . Focusing on permanent isotropic spring networks it is shown theoretically and computationally that in general G(t ) =C (t ) | τ=C(t ) | γ+Geq for t >0 with Geq being the static equilibrium shear modulus. G (t ) and C(t ) | γ thus must become different for solids and it is impossible to obtain Geq alone from C(t ) | γ as often assumed. We comment briefly on self-assembled transient networks where Geq(f ) must vanish for a finite scission-recombination frequency f . We argue that G(t ) =C (t ) | τ=C(t ) | γ should reveal an intermediate plateau set by the shear modulus Geq(f =0 ) of the quenched network.

  8. Single-shot electron bunch length measurements using a spatial electro-optical autocorrelation interferometer.

    PubMed

    Sütterlin, Daniel; Erni, Daniel; Schlott, Volker; Sigg, Hans; Jäckel, Heinz; Murk, Axel

    2010-10-01

    A spatial, electro-optical autocorrelation (EOA) interferometer using the vertically polarized lobes of coherent transition radiation (CTR) has been developed as a single-shot electron bunch length monitor at an optical beam port downstream the 100 MeV preinjector LINAC of the Swiss Light Source. This EOA monitor combines the advantages of step-scan interferometers (high temporal resolution) [D. Mihalcea et al., Phys. Rev. ST Accel. Beams 9, 082801 (2006) and T. Takahashi and K. Takami, Infrared Phys. Technol. 51, 363 (2008)] and terahertz-gating technologies [U. Schmidhammer et al., Appl. Phys. B: Lasers Opt. 94, 95 (2009) and B. Steffen et al., Phys. Rev. ST Accel. Beams 12, 032802 (2009)] (fast response), providing the possibility to tune the accelerator with an online bunch length diagnostics. While a proof of principle of the spatial interferometer was achieved by step-scan measurements with far-infrared detectors, the single-shot capability of the monitor has been demonstrated by electro-optical correlation of the spatial CTR interference pattern with fairly long (500 ps) neodymium-doped yttrium aluminum garnet (Nd:YAG) laser pulses in a ZnTe crystal. In single-shot operation, variations of the bunch length between 1.5 and 4 ps due to different phase settings of the LINAC bunching cavities have been measured with subpicosecond time resolution.

  9. CUSUM chart to monitor autocorrelated counts using Negative Binomial GARMA model.

    PubMed

    Albarracin, Orlando Yesid Esparza; Alencar, Airlane Pereira; Lee Ho, Linda

    2017-01-01

    Cumulative sum control charts have been used for health surveillance due to its efficiency to detect soon small shifts in the monitored series. However, these charts may fail when data are autocorrelated. An alternative procedure is to build a control chart based on the residuals after fitting autoregressive moving average models, but these models usually assume Gaussian distribution for the residuals. In practical health surveillance, count series can be modeled by Poisson or Negative Binomial regression, this last to control overdispersion. To include serial correlations, generalized autoregressive moving average models are proposed. The main contribution of the current article is to measure the impact, in terms of average run length on the performance of cumulative sum charts when the serial correlation is neglected in the regression model. Different statistics based on transformations, the deviance residual, and the likelihood ratio are used to build cumulative sum control charts to monitor counts with time varying means, including trend and seasonal effects. The monitoring of the weekly number of hospital admissions due to respiratory diseases for people aged over 65 years in the city São Paulo-Brazil is considered as an illustration of the current method.

  10. Estimating where and how animals travel: an optimal framework for path reconstruction from autocorrelated tracking data.

    PubMed

    Fleming, C H; Fagan, W F; Mueller, T; Olson, K A; Leimgruber, P; Calabrese, J M

    2016-03-01

    An animal's trajectory is a fundamental object of interest in movement ecology, as it directly informs a range of topics from resource selection to energy expenditure and behavioral states. Optimally inferring the mostly unobserved movement path and its dynamics from a limited sample of telemetry observations is a key unsolved problem, however. The field of geostatistics has focused significant attention on a mathematically analogous problem that has a statistically optimal solution coined after its inventor, Krige. Kriging revolutionized geostatistics and is now the gold standard for interpolating between a limited number of autocorrelated spatial point observations. Here we translate Kriging for use with animal movement data. Our Kriging formalism encompasses previous methods to estimate animal's trajectories--the Brownian bridge and continuous-time correlated random walk library--as special cases, informs users as to when these previous methods are appropriate, and provides a more general method when they are not. We demonstrate the capabilities of Kriging on a case study with Mongolian gazelles where, compared to the Brownian bridge, Kriging with a more optimal model was 10% more precise in interpolating locations and 500% more precise in estimating occurrence areas.

  11. Microscopic observation of the segmental orientation autocorrelation function for entangled and constrained polymer chains

    NASA Astrophysics Data System (ADS)

    Mordvinkin, Anton; Saalwächter, Kay

    2017-03-01

    Previous work on probing the dynamics of reptating polymer chains in terms of the segmental orientation autocorrelation function (OACF) by multiple-quantum (MQ) NMR relied on the time-temperature superposition (TTS) principle as applied to normalized double-quantum (DQ) build-up curves. Alternatively, an initial-rise analysis of the latter is also possible. These approaches are subject to uncertainties related to the relevant segmental shift factor or parasitic signals and inhomogeneities distorting the build-up at short times, respectively. Here, we present a simple analytical fitting approach based upon a power-law model of the OACF, by the way of which an effective power-law time scaling exponent and the amplitude of the OACF can be estimated from MQ NMR data at any given temperature. This obviates the use of TTS and provides a robust and independent probe of the shape of the OACF. The approach is validated by application to polymer melts of variable molecular weight as well as elastomers. We anticipate a wide range of applications, including the study of physical networks with labile junctions.

  12. Seismic Spatial Autocorrelation as a Technique to Track Changes in the Permafrost Active Layer

    NASA Astrophysics Data System (ADS)

    Abbott, R. E.

    2013-12-01

    We present preliminary results from an effort to continuously track freezing and thawing of the permafrost active layer using a small-aperture seismic array. The 7-element array of three-component posthole seismometers is installed on permafrost at Poker Flat Research Range, near Fairbanks, Alaska. The array is configured in two three-station circles with 75 and 25 meter radii that share a common center station. This configuration is designed to resolve omnidirectional, high-frequency seismic microtremor (i.e. ambient noise). Microtremor is continuously monitored and the data are processed using the spatial autocorrelation (SPAC) method. The resulting SPAC coefficients are then inverted for shear-wave velocity structure versus depth. Thawed active-layer soils have a much slower seismic velocity than frozen soils, allowing us to track the depth and intensity of thawing. Persistent monitoring on a permanent array would allow for a way to investigate year-to-year changes without costly site visits. Results from the seismic array will compared to, and correlated with, other measurement techniques, such as physical probing and remote sensing methods. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

  13. Single-shot electron bunch length measurements using a spatial electro-optical autocorrelation interferometer

    NASA Astrophysics Data System (ADS)

    Sütterlin, Daniel; Erni, Daniel; Schlott, Volker; Sigg, Hans; Jäckel, Heinz; Murk, Axel

    2010-10-01

    A spatial, electro-optical autocorrelation (EOA) interferometer using the vertically polarized lobes of coherent transition radiation (CTR) has been developed as a single-shot electron bunch length monitor at an optical beam port downstream the 100 MeV preinjector LINAC of the Swiss Light Source. This EOA monitor combines the advantages of step-scan interferometers (high temporal resolution) [D. Mihalcea et al., Phys. Rev. ST Accel. Beams 9, 082801 (2006) and T. Takahashi and K. Takami, Infrared Phys. Technol. 51, 363 (2008)] and terahertz-gating technologies [U. Schmidhammer et al., Appl. Phys. B: Lasers Opt. 94, 95 (2009) and B. Steffen et al., Phys. Rev. ST Accel. Beams 12, 032802 (2009)] (fast response), providing the possibility to tune the accelerator with an online bunch length diagnostics. While a proof of principle of the spatial interferometer was achieved by step-scan measurements with far-infrared detectors, the single-shot capability of the monitor has been demonstrated by electro-optical correlation of the spatial CTR interference pattern with fairly long (500 ps) neodymium-doped yttrium aluminum garnet (Nd:YAG) laser pulses in a ZnTe crystal. In single-shot operation, variations of the bunch length between 1.5 and 4 ps due to different phase settings of the LINAC bunching cavities have been measured with subpicosecond time resolution.

  14. Molecular-dynamics calculations of the velocity autocorrelation function: Hard-sphere results

    NASA Astrophysics Data System (ADS)

    Erpenbeck, Jerome J.; Wood, Wiilliam W.

    1985-07-01

    The velocity autocorrelation function for the hard-sphere fluid is computed for ten values of the volume ranging from 25 to 1.6 times the close-packed volume V0 for systems of from 108 to 4000 hard spheres, using a Monte Carlo, molecular-dynamics technique. The results are compared with the theoretical predictions of the mode-coupling theory, modified to take into account the finite size of the system and the periodic boundary conditions. The data are found to be in good agreement with the theory, evaluated using Enskog values for the transport coefficients, for values of the time greater than roughly 15 to 30 mean free times (depending on density), for volumes as small as 2V0. The higher-density results do not agree with the theory, unless the actual transport coefficients (evaluated using molecular dynamics) are used in the theory. The latter version of the theory, however, fails to fit the data at lower densities, except at very long times. To answer the recent critique by Fox, the data are further compared with the theory over time intervals for which the molecular-dynamics trajectories retain some measure of accuracy. The agreement between the data and the theory is largely unaffected, except at a volume 1.8V0 for which there is a marginally significant difference at very long times only.

  15. Autocorrelation structure at rest predicts value correlates of single neurons during reward-guided choice

    PubMed Central

    Cavanagh, Sean E; Wallis, Joni D; Kennerley, Steven W; Hunt, Laurence T

    2016-01-01

    Correlates of value are routinely observed in the prefrontal cortex (PFC) during reward-guided decision making. In previous work (Hunt et al., 2015), we argued that PFC correlates of chosen value are a consequence of varying rates of a dynamical evidence accumulation process. Yet within PFC, there is substantial variability in chosen value correlates across individual neurons. Here we show that this variability is explained by neurons having different temporal receptive fields of integration, indexed by examining neuronal spike rate autocorrelation structure whilst at rest. We find that neurons with protracted resting temporal receptive fields exhibit stronger chosen value correlates during choice. Within orbitofrontal cortex, these neurons also sustain coding of chosen value from choice through the delivery of reward, providing a potential neural mechanism for maintaining predictions and updating stored values during learning. These findings reveal that within PFC, variability in temporal specialisation across neurons predicts involvement in specific decision-making computations. DOI: http://dx.doi.org/10.7554/eLife.18937.001 PMID:27705742

  16. Simulation and analysis of GPR signal based on stochastic media model with an ellipsoidal autocorrelation function

    NASA Astrophysics Data System (ADS)

    Jiang, Zimeng; Zeng, Zhaofa; Li, Jing; Liu, Fengshan; Li, Wenben

    2013-12-01

    Target detection using ground penetrating radar (GPR) is based on the contrast between the electrical parameters of the target and the background medium, such as dielectric permittivity, conductivity and permeability. The application mainly concentrates on the detection of the medium interface and the target shape. In any theoretical study, a simulation model is built with a homogeneous medium. However, real detection encounters heterogeneous media which might produce scattering and diffraction at electrical interfaces and distort the radar pulse shape and affect the detection resolution. In this paper, we build multi-scale random media model with an ellipsoidal autocorrelation function and use FDTD method to simulate the GPR signal response. We then estimate and analyze the arrival time, layer thickness, permittivity and the physics relation in different scale random models according to the S transform method and the transmission wave method. The results demonstrate that we can use GPR to obtain geophysical information of multi-scale heterogeneous media, and provide a foundation for real media detection and complex media inversion.

  17. Time dependence of the velocity autocorrelation function of a fluid: An eigenmode analysis of dynamical processes

    NASA Astrophysics Data System (ADS)

    Bellissima, S.; Neumann, M.; Guarini, E.; Bafile, U.; Barocchi, F.

    2015-10-01

    The velocity autocorrelation function (VAF), a key quantity in the atomic-scale dynamics of fluids, has been the first paradigmatic example of a long-time tail phenomenon, and much work has been devoted to detecting such long-lasting correlations and understanding their nature. There is, however, much more to the VAF than simply the evidence of this long-time dynamics. A unified description of the VAF from very short to long times, and of the way it changes with varying density, is still missing. Here we show that an approach based on very general principles makes such a study possible and opens the way to a detailed quantitative characterization of the dynamical processes involved at all time scales. From the analysis of molecular dynamics simulations for a slightly supercritical Lennard-Jones fluid at various densities, we are able to evidence the presence of distinct fast and slow decay channels for the velocity correlation on the time scale set by the collision rate. The density evolution of these decay processes is also highlighted. The method presented here is very general, and its application to the VAF can be considered as an important example.

  18. 76 FR 66965 - Treasure Coast Specialty Pharmacy Decision and Order

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-28

    ..., 749 F.2d 297 (6th Cir. 1984); Puerto Rico Acqueduct & Sewer Auth. v. EPA, 35 F.3d 600, 605 (1st Cir... Registration, BT9856002, issued to Treasure Coast Specialty Pharmacy, be, and it hereby is, revoked. I further... registration, be, and it hereby is, denied. This Order is effective immediately. Dated: October 7,...

  19. Creating Research-Rich Learning Experiences and Quantitative Skills in a 1st Year Earth Systems Course

    NASA Astrophysics Data System (ADS)

    King, P. L.; Eggins, S.; Jones, S.

    2014-12-01

    We are creating a 1st year Earth Systems course at the Australian National University that is built around research-rich learning experiences and quantitative skills. The course has top students including ≤20% indigenous/foreign students; nonetheless, students' backgrounds in math and science vary considerably posing challenges for learning. We are addressing this issue and aiming to improve knowledge retention and deep learning by changing our teaching approach. In 2013-2014, we modified the weekly course structure to a 1hr lecture; a 2hr workshop with hands-on activities; a 2hr lab; an assessment piece covering all face-to-face activities; and a 1hr tutorial. Our new approach was aimed at: 1) building student confidence with data analysis and quantitative skills through increasingly difficult tasks in science, math, physics, chemistry, climate science and biology; 2) creating effective learning groups using name tags and a classroom with 8-person tiered tables; 3) requiring students to apply new knowledge to new situations in group activities, two 1-day field trips and assessment items; 4) using pre-lab and pre-workshop exercises to promote prior engagement with key concepts; 5) adding open-ended experiments to foster structured 'scientific play' or enquiry and creativity; and 6) aligning the assessment with the learning outcomes and ensuring that it contains authentic and challenging southern hemisphere problems. Students were asked to design their own ocean current experiment in the lab and we were astounded by their ingenuity: they simulated the ocean currents off Antarctica; varied water density to verify an equation; and examined the effect of wind and seafloor topography on currents. To evaluate changes in student learning, we conducted surveys in 2013 and 2014. In 2014, we found higher levels of student engagement with the course: >~80% attendance rates and >~70% satisfaction (20% neutral). The 2014 cohort felt that they were more competent in writing

  20. PREFACE: 1st International School and Conference "Saint Petersburg OPEN 2014" on Optoelectronics, Photonics, Engineering and Nanostructures

    NASA Astrophysics Data System (ADS)

    2014-09-01

    Dear Colleagues, 1st International School and Conference "Saint Petersburg OPEN 2014" on Optoelectronics, Photonics, Engineering and Nanostructures was held on March 25 - 27, 2014 at St. Petersburg Academic University - Nanotechnology Research and Education Centre of the Russian Academy of Sciences. The School and Conference included a series of invited talks given by leading professors with the aim to introduce young scientists with actual problems and major advances in physics and technology. The keynote speakers were: Mikhail Glazov (Ioffe Physico-Technical Institute RAS, Russia) Vladimir Dubrovskii (Saint Petersburg Academic University RAS, Russia) Alexey Kavokin (University of Southampton, United Kingdom and St. Petersburg State University, Russia) Vladimir Korenev (Ioffe Physico-Technical Institute RAS, Russia) Sergey Kukushkin (Institute of Problems of Mechanical Engineering RAS, Russia) Nikita Pikhtin (Ioffe Physico-Technical Institute RAS, Russia and "Elfolum" Ltd., Russia) Dmitry Firsov (Saint Petersburg State Polytechnical University, Russia) During the poster session all undergraduate and graduate students attending the conference presented their works. Sufficiently large number of participants with more than 160 student attendees from all over the world allowed the Conference to provide a fertile ground for the fruitful discussions between the young scientists as well as to become a perfect platform for the valuable discussions between student authors and highly experienced scientists. The best student papers, which were selected by the Program Committee and by the invited speakers basing on the theses and their poster presentation, were awarded with diplomas of the conference - see the photos. This year's School and Conference is supported by SPIE (The International Society for Optics and Photonics), OSA (The Optical Society), St. Petersburg State Polytechnical University and by Skolkovo Foundation. It is a continuation of the annual schools and

  1. Mean-field approximation for a limit order driven market model

    NASA Astrophysics Data System (ADS)

    Slanina, František

    2001-11-01

    A mean-field variant of the model of limit order driven market introduced recently by Maslov is formulated and solved. The agents do not have any strategies and the memory of the system is kept within the order book. We show that the evolution of the order book is governed by a matrix multiplicative process. The resulting stationary distribution of step-to-step price changes is calculated. It exhibits a power-law tail with exponent 2. We obtain also the price autocorrelation function, which agrees qualitatively with the experimentally observed negative autocorrelation for short times.

  2. Extraordinary induction heating effect near the first order Curie transition

    NASA Astrophysics Data System (ADS)

    Barati, M. R.; Selomulya, C.; Sandeman, K. G.; Suzuki, K.

    2014-10-01

    While materials with a 1st order Curie transition (TC) are known for the magnetic cooling effect due to the reversibility of their large entropy change, they also have a great potential as a candidate material for induction heating where a large loss power is required under a limited alternating magnetic field. We have carried out a proof-of-concept study on the induction heating effect in 1st order ferromagnetic materials where the temperature is self-regulated at TC. LaFe11.57Si1.43H1.75, a well-known magnetocaloric material, was employed in this study because TC of this compound (319 K) resides in the ideal temperature range for hyperthermia treatment of cancerous cells. It is found that the hysteresis loss of LaFe11.57Si1.43H1.75 increases dramatically near TC due to the magnetic phase coexistence associated with the 1st order magnetic transition. The spontaneous magnetization (Ms) shows a very abrupt decrease from 110 Am2kg-1 at 316 K to zero at 319 K. This large Ms immediately below TC along with the enhanced irreversibility of the hysteresis curve result in a specific absorption rate as large as 0.5 kWg-1 under a field of 8.8 kAm-1 at 279 kHz. This value is nearly an order of magnitude larger than that observed under the same condition for conventional iron oxide-based materials. Moreover, the large heating effect is self-regulated at the 1st order TC (319 K). This proof-of-concept study shows that the extraordinary heating effect near the 1st order Curie point opens up a novel alloy design strategy for large, self-regulated induction heating.

  3. Spatial autocorrelation and mean intercept length analysis of trabecular bone anisotropy applied to in vivo magnetic resonance imaging.

    PubMed

    Wald, Michael J; Vasilic, Branimir; Saha, Punam K; Wehrli, Felix W

    2007-03-01

    Osteoporosis is characterized by bone loss and deterioration of the trabecular bone (TB) architecture that leads to impaired overall mechanical strength of the bone. Bone mineral density (BMD) measured by dual-energy x-ray absorptiometry is currently the standard clinical metric assessing bone integrity but it fails to capture the structural changes in the TB. Recent research suggests that structure contributes to bone strength in a manner complementary to BMD. Besides parameters of scale such as the mean TB thickness and mean bone volume fraction, parameters describing the anisotropy of the trabecular architecture play an important role in the characterization of TB since trabeculae are preferentially oriented along the direction of local loading. Therefore, the degree of structural anisotropy is of pivotal importance to the bone's mechanical competence. The most common method for measuring structural anisotropy of TB is the mean-intercept length (MIL). In this work we present a method, based on the three-dimensional spatial autocorrelation function (ACF), for mapping of the full structural anisotropy ellipsoid of both TB thickness and spacing and we examine its performance as compared to that of MIL. Not only is the ACF method faster by several orders of magnitude, it is also considerably more robust to noise. Further, it is applicable at lower spatial resolution and is relatively insensitive to image shading. The chief reason for ACF's superior performance is that it does not require binarization, which is difficult to achieve in the limited spatial regime of in vivo magnetic resonance imaging. MIL and ACF have been applied to high-resolution magnetic resonances images of the tibia in a group of ten healthy postmenopausal women by comparing the structural anisotropy and principal direction of the computed fabric tensor for each method. While there is fair agreement between the two methods, ACF analysis yielded greater anisotropy than MIL for both TB thickness

  4. Power-law decay of the velocity autocorrelation function of a granular fluid in the homogeneous cooling state.

    PubMed

    Brey, J Javier; Ruiz-Montero, M J

    2015-01-01

    The hydrodynamic part of the velocity autocorrelation function of a granular fluid in the homogeneous cooling state has been calculated by using mode-coupling theory for a finite system with periodic boundary conditions. The existence of the shearing instability, leading to a divergent behavior of the velocity flow fluctuations, is taken into account. A time region in which the velocity autocorrelation function exhibits a power-law decay, when time is measured by the number of collisions per particle, has been been identified. Also the explicit form of the exponential asymptotic long time decay has been obtained. The theoretical prediction for the power-law decay is compared with molecular dynamics simulation results, and a good agreement is found, after taking into account finite size corrections. The effects of approaching the shearing instability are also explored.

  5. The influence of autocorrelation in signature extraction: An example from a geobotanical investigation of Cotter Basin, Montana

    NASA Technical Reports Server (NTRS)

    Labovitz, M. L.; Masuoka, E. J. (Principal Investigator)

    1981-01-01

    The presence of positive serial correlation (autocorrelation) in remotely sensed data results in an underestimate of the variance-covariance matrix when calculated using contiguous pixels. This underestimate produces an inflation in F statistics. For a set of Thematic Mapper Simulator data (TMS), used to test the ability to discriminate a known geobotanical anomaly from its background, the inflation in F statistics related to serial correlation is between 7 and 70 times. This means that significance tests of means of the spectral bands initially appear to suggest that the anomalous site is very different in spectral reflectance and emittance from its background sites. However, this difference often disappears and is always dramatically reduced when compared to frequency distributions of test statistics produced by the comparison of simulated training sets possessing equal means, but which are composed of autocorrelated observations.

  6. Proceedings of the IEEE International Workshop on Safety of Systems (1st) held in Monterey, California on 15-16 Mar 2007

    DTIC Science & Technology

    2007-03-01

    Programming: Concurrency Page 36© 2005 by Andrew Kornecki and Janusz Zalewski • An informal scan of the real-time (embedded, dedicated, safety...Press, pp. 40-47. 8. R. Sterritt, D.F. Bantz, “PAC-MEN: Personal Autonomic Computing Monitoring Environments,” In Proceedings of IEEE DEXA 2004...Autonomic Computing Environment,” In Proceedings of IEEE DEXA 2003 Workshops - 1st International Workshop on Autonomic Computing Systems, Prague, Czech

  7. Injuries and Physical Fitness Before and After Deployments of the 10th Mountain Division to Afghanistan and the 1st Cavalry Division to Iraq, September 2005 - October 2008

    DTIC Science & Technology

    2008-10-01

    determined using the McNemar Test. The McNemar Test allows comparison of frequency data involving repeated measures on the same individuals.(71) (3...and After Deployment of the 10thMt Cohort (n=505 Men) Injury Index Injury Incidence p-value ( McNemar Test) Predeployment Postdeployment Period 1...Injury Incidence Before and After Deployment of the 1stCav Cohort – Men (n=3242) Injury Index Injury Incidence p-value ( McNemar Test) Predeployment

  8. Similarity searching in databases of flexible 3D structures using autocorrelation vectors derived from smoothed bounded distance matrices.

    PubMed

    Rhodes, Nicholas; Clark, David E; Willett, Peter

    2006-01-01

    This paper presents an exploratory study of a novel method for flexible 3-D similarity searching based on autocorrelation vectors and smoothed bounded distance matrices. Although the new approach is unable to outperform an existing 2-D similarity searching in terms of enrichment factors, it is able to retrieve different compounds at a given percentage of the hit-list and so may be a useful adjunct to other similarity searching methods.

  9. Generation of High Resolution Radar Range Profiles and Range Profile Auto-Correlation Functions Using Stepped-Frequency Pulse Train

    DTIC Science & Technology

    1984-10-18

    resulting range resolution (of both the profile and itg auto- correlation function) is determined by the total bandwidth (i.e., the fre- quency spread...contrast provided by the resulting range profiles and range profile auto-correlation functions is determined. The target-to-clutter contrast provided by the...SIMULATION RESULTS FOR RANGE-PROFILES AND RANGE-PROFILE 86 AUTO -CORRELATION FIJNCTIONS OBTAINED BY PROCESSING RETURNS FROM FR9QUENCY-STEPPED PULSE

  10. Variability of human gait: effect of backward walking and dual-tasking on the presence of long-range autocorrelations.

    PubMed

    Bollens, Benjamin; Crevecoeur, Frédéric; Detrembleur, Christine; Warlop, Thibault; Lejeune, Thierry M

    2014-04-01

    Information from the central and peripheral nervous systems is continuously integrated to produce a stable gait pattern. However, stride duration fluctuates in a complex manner in healthy subjects, exhibiting long-range autocorrelations that can span over hundreds of consecutive strides. The present study was conducted to explore the mechanisms controlling the long-term fluctuation dynamics of gait. In the first part of the study, stride duration variability was evaluated on a treadmill during forward (FW) and backward walking (BW). Despite the modification of the biomechanical constraints imposed on the locomotor system, the characteristics of the long-range autocorrelations remained unchanged in both modes of locomotion (FW: H = 0.79 ± 0.04 and α = 0.58 ± 0.13; BW: H = 0.79 ± 0.11 and α = 0.53 ± 0.25). In the second part of the study, stride duration variability was assessed while the subjects were performing a dual-task paradigm that combined gait and mental calculation. The long-term variability of stride duration was similar during usual walking (H = 0.80 ± 0.06 and α = 0.57 ± 0.13) and in dual-tasking (H = 0.77 ± 0.06 and α = 0.52 ± 0.16), whereas walking altered the performance of the cognitive task. Hence, the biomechanical and cognitive interferences imposed in the present study were not sufficient to induce a modification of the long-range autocorrelations highlighted in walking variability. These observations underline the robustness of the long-range autocorrelations.

  11. Possible origin of the non-linear long-term autocorrelations within the Gaussian regime

    NASA Astrophysics Data System (ADS)

    Kutner, Ryszard; Świtała, Filip

    2003-12-01

    time series), which are collected with a discrete time step, we used in the continuous-time series produced by the model a discretization procedure. We observed that such a procedure generates, in general, long-range non-linear autocorrelations even in the Gaussian regime, which appear to be similar to those observed, e.g., in the financial time series (Phys. A 287 (2000) 396; Phys. A 299 (2001) 1; Phys. A 299 (2001) 16; Phys. A 299 (2001) 16), although single steps of the walker within continuous time are, by definition, uncorrelated. This suggests a suprising origin of long-range non-linear autocorrelations alternative to the one proposed very recently (cf. Mosaliver et al. (Phys. Rev. E 67 (2003) 021112) and refs. therein) although both approaches involve related variants of the well-known continuous-time random walk formalism applied yet in many different branches of knowledge (Phys. Rep. 158 (1987) 263; Phys. Rep. 195 (1990) 127; in: A. Bunde, S. Havlin (Eds.), Fractals in Science, Springer, Berlin, 1995, p. 1).

  12. Higher order modes in photonic crystal slabs.

    PubMed

    Gansch, Roman; Kalchmair, Stefan; Detz, Hermann; Andrews, Aaron M; Klang, Pavel; Schrenk, Werner; Strasser, Gottfried

    2011-08-15

    We present a detailed investigation of higher order modes in photonic crystal slabs. In such structures the resonances exhibit a blue-shift compared to an ideal two-dimensional photonic crystal, which depends on the order of the slab mode and the polarization. By fabricating a series of photonic crystal slab photo detecting devices, with varying ratios of slab thickness to photonic crystal lattice constant, we are able to distinguish between 0th and 1st order slab modes as well as the polarization from the shift of resonances in the photocurrent spectra. This method complements the photonic band structure mapping technique for characterization of photonic crystal slabs.

  13. Explaining local-scale species distributions: relative contributions of spatial autocorrelation and landscape heterogeneity for an avian assemblage

    USGS Publications Warehouse

    Mattsson, Brady J.; Zipkin, Elise F.; Gardner, Beth; Blank, Peter J.; Sauer, John R.; Royle, J. Andrew

    2013-01-01

    Understanding interactions between mobile species distributions and landcover characteristics remains an outstanding challenge in ecology. Multiple factors could explain species distributions including endogenous evolutionary traits leading to conspecific clustering and endogenous habitat features that support life history requirements. Birds are a useful taxon for examining hypotheses about the relative importance of these factors among species in a community. We developed a hierarchical Bayes approach to model the relationships between bird species occupancy and local landcover variables accounting for spatial autocorrelation, species similarities, and partial observability. We fit alternative occupancy models to detections of 90 bird species observed during repeat visits to 316 point-counts forming a 400-m grid throughout the Patuxent Wildlife Research Refuge in Maryland, USA. Models with landcover variables performed significantly better than our autologistic and null models, supporting the hypothesis that local landcover heterogeneity is important as an exogenous driver for species distributions. Conspecific clustering alone was a comparatively poor descriptor of local community composition, but there was evidence for spatial autocorrelation in all species. Considerable uncertainty remains whether landcover combined with spatial autocorrelation is most parsimonious for describing bird species distributions at a local scale. Spatial structuring may be weaker at intermediate scales within which dispersal is less frequent, information flows are localized, and landcover types become spatially diversified and therefore exhibit little aggregation. Examining such hypotheses across species assemblages contributes to our understanding of community-level associations with conspecifics and landscape composition.

  14. Explaining Local-Scale Species Distributions: Relative Contributions of Spatial Autocorrelation and Landscape Heterogeneity for an Avian Assemblage

    PubMed Central

    Mattsson, Brady J.; Zipkin, Elise F.; Gardner, Beth; Blank, Peter J.; Sauer, John R.; Royle, J. Andrew

    2013-01-01

    Understanding interactions between mobile species distributions and landcover characteristics remains an outstanding challenge in ecology. Multiple factors could explain species distributions including endogenous evolutionary traits leading to conspecific clustering and endogenous habitat features that support life history requirements. Birds are a useful taxon for examining hypotheses about the relative importance of these factors among species in a community. We developed a hierarchical Bayes approach to model the relationships between bird species occupancy and local landcover variables accounting for spatial autocorrelation, species similarities, and partial observability. We fit alternative occupancy models to detections of 90 bird species observed during repeat visits to 316 point-counts forming a 400-m grid throughout the Patuxent Wildlife Research Refuge in Maryland, USA. Models with landcover variables performed significantly better than our autologistic and null models, supporting the hypothesis that local landcover heterogeneity is important as an exogenous driver for species distributions. Conspecific clustering alone was a comparatively poor descriptor of local community composition, but there was evidence for spatial autocorrelation in all species. Considerable uncertainty remains whether landcover combined with spatial autocorrelation is most parsimonious for describing bird species distributions at a local scale. Spatial structuring may be weaker at intermediate scales within which dispersal is less frequent, information flows are localized, and landcover types become spatially diversified and therefore exhibit little aggregation. Examining such hypotheses across species assemblages contributes to our understanding of community-level associations with conspecifics and landscape composition. PMID:23393564

  15. Ultra-Deep Seismic Reflection Profiles of the Western U.S. from Autocorrelation of USArray Recordings

    NASA Astrophysics Data System (ADS)

    Cabolova, A.; Brown, L. D.

    2012-12-01

    A core tenet of the emerging field of seismic interferometry is that autocorrelation of the transmission response recorded at a given seismic station is equivalent to its reflection response. This relation holds true for both specific (earthquake) and distributed (ambient noise) sources. In principle therefore one should be able to reconstruct the equivalent of a zero-offset, surface source-receiver reflection profile from simply autocorrelating the recordings of "natural" sources along a line of seismograph stations. In practice summation of a number of sources from an adequate spatial distribution of quasi random sources is needed to suppress artifacts and enhance the desired reflection response. Recently Ruigrok and Wapennar (2012) reported a lithospheric P-wave reflectivity profile by applying this technique to PKP, PKiKP and PKIKP phases of arthquakes recorded on Hi-CLIMB receivers crossing the Himalaya and southern Tibetan Plateau. Here we show the results of applying similar autocorrelation techniques to both ambient noise and earthquake suites recorded by USArray stations in New Mexico and Arizona to produce P and S wave reflection profiles of lithospheric structure. Our results demonstrate that while this novel approach can provide new (albeit low resolution compared to controlled source surveys) , reflection profiles of lithospheric structure, care must be used to discriminate true reflectivity from artifacts generate by the limited distribution of source regions. However, since the quality of the image is related to stacking fold, results from permanent or long term stations can only improve in clarity and resolution with time.

  16. The analysis of trend variations of reference evapotranspiration via eliminating the significance effect of all autocorrelation coefficients

    NASA Astrophysics Data System (ADS)

    Amirataee, Babak; Montaseri, Majid; Sanikhani, Hadi

    2016-10-01

    Reference evapotranspiration (ET0) is considered a key parameter for evaluating the climatic changes as well as spatial and temporal patterns of parameters influencing the eco-hydrological processes. The analysis of trend variations of this index can be used to determine appropriate strategies in planning and management of water resources. In this paper, the trend variations of monthly and annual ET0 in Urmia Lake basin, located in the northwest of Iran, have been analyzed using data from 14 synoptic stations in the study area. Regarding the significant effect of autocorrelation coefficients with different lags on trend variations of ET0, this paper has resorted to modified Mann-Kendall test via eliminating the significance effect of autocorrelation coefficients with different lags to analyze the trend variations. Furthermore, Theil-Sen estimator has been used to determine the slope of trend line of ET0. The results indicated an increasing trend in ET0 values at all the studied stations. Having used the modified Mann-Kendall test, the values of significant increasing (positive) trend, which were estimated using common Mann-Kendall test, dramatically decreased. As such, the values of only 7 stations have been significant at 95 % level. The results confirmed the need for eliminating the significance effect of autocorrelation coefficients with different lags to determine and evaluate the trend of hydrological variables.

  17. Explaining local-scale species distributions: relative contributions of spatial autocorrelation and landscape heterogeneity for an avian assemblage.

    PubMed

    Mattsson, Brady J; Zipkin, Elise F; Gardner, Beth; Blank, Peter J; Sauer, John R; Royle, J Andrew

    2013-01-01

    Understanding interactions between mobile species distributions and landcover characteristics remains an outstanding challenge in ecology. Multiple factors could explain species distributions including endogenous evolutionary traits leading to conspecific clustering and endogenous habitat features that support life history requirements. Birds are a useful taxon for examining hypotheses about the relative importance of these factors among species in a community. We developed a hierarchical Bayes approach to model the relationships between bird species occupancy and local landcover variables accounting for spatial autocorrelation, species similarities, and partial observability. We fit alternative occupancy models to detections of 90 bird species observed during repeat visits to 316 point-counts forming a 400-m grid throughout the Patuxent Wildlife Research Refuge in Maryland, USA. Models with landcover variables performed significantly better than our autologistic and null models, supporting the hypothesis that local landcover heterogeneity is important as an exogenous driver for species distributions. Conspecific clustering alone was a comparatively poor descriptor of local community composition, but there was evidence for spatial autocorrelation in all species. Considerable uncertainty remains whether landcover combined with spatial autocorrelation is most parsimonious for describing bird species distributions at a local scale. Spatial structuring may be weaker at intermediate scales within which dispersal is less frequent, information flows are localized, and landcover types become spatially diversified and therefore exhibit little aggregation. Examining such hypotheses across species assemblages contributes to our understanding of community-level associations with conspecifics and landscape composition.

  18. Measurement of the nonlinear refractive index of tellurite glass fiber by using induced grating autocorrelation technique

    NASA Astrophysics Data System (ADS)

    Traore, Aboubakar

    Nonlinear phenomena in optical fibers have been attracting considerable attention because of the rapid growth of the fiber optics communication industry. The increasing demand in internet use and the expansion of telecommunications in the developing world have triggered the need for high capacity and ultra-fast communication devices and also the need to increase the number of transmission channels in the fibers. Wavelength Division Multiplexing (WDM) and Dense Wavelength Division Multiplexing (DWDM) systems are capable of transmitting large volumes of data at very high rates into huge numbers of optical transmission channels. This ability is limited by the gain bandwidth of Silica based fiber optics amplifiers already installed in the communication networks. Tellurite based fiber amplifiers offer the necessary bandwidth for amplification of WDM and DWDM channels. To investigate the nonlinear properties of the optical fibers in this research, we used a 10 picoseconds pulse width passively mode-locked Nd:Vanadate ( Nd:YVO4) laser operating at 1342nm with a repetition rate of 76 MHz. We accurately measured the nonlinear refractive index of single mode silica fibers utilizing the Induced Grating Autocorrelation (IGA) technique. IGA technique was extended furthermore to study nonlinear effects in multimode fibers, and for the first time, we successfully measured the nonlinear refractive index (n2) of a multimode silica fiber. Confident of the ability of IGA technique for determining n 2 of multimode silica fibers, we measured the nonlinear refractive index of multimode Tellurite glass fibers with length as short as 0.5 meter. The goal of this work is to provide accurate and reliable information on the nonlinear optical properties of Tellurite glass fibers, novel fibers with promising future for developing ultrafast and high transmission capacity communication devices.

  19. Autocorrelation descriptor improvements for QSAR: 2DA_Sign and 3DA_Sign

    NASA Astrophysics Data System (ADS)

    Sliwoski, Gregory; Mendenhall, Jeffrey; Meiler, Jens

    2016-03-01

    Quantitative structure-activity relationship (QSAR) is a branch of computer aided drug discovery that relates chemical structures to biological activity. Two well established and related QSAR descriptors are two- and three-dimensional autocorrelation (2DA and 3DA). These descriptors encode the relative position of atoms or atom properties by calculating the separation between atom pairs in terms of number of bonds (2DA) or Euclidean distance (3DA). The sums of all values computed for a given small molecule are collected in a histogram. Atom properties can be added with a coefficient that is the product of atom properties for each pair. This procedure can lead to information loss when signed atom properties are considered such as partial charge. For example, the product of two positive charges is indistinguishable from the product of two equivalent negative charges. In this paper, we present variations of 2DA and 3DA called 2DA_Sign and 3DA_Sign that avoid information loss by splitting unique sign pairs into individual histograms. We evaluate these variations with models trained on nine datasets spanning a range of drug target classes. Both 2DA_Sign and 3DA_Sign significantly increase model performance across all datasets when compared with traditional 2DA and 3DA. Lastly, we find that limiting 3DA_Sign to maximum atom pair distances of 6 Å instead of 12 Å further increases model performance, suggesting that conformational flexibility may hinder performance with longer 3DA descriptors. Consistent with this finding, limiting the number of bonds in 2DA_Sign from 11 to 5 fails to improve performance.

  20. ROTATION PERIODS OF 34,030 KEPLER MAIN-SEQUENCE STARS: THE FULL AUTOCORRELATION SAMPLE

    SciTech Connect

    McQuillan, A.; Mazeh, T.; Aigrain, S.

    2014-04-01

    We analyzed three years of data from the Kepler space mission to derive rotation periods of main-sequence stars below 6500 K. Our automated autocorrelation-based method detected rotation periods between 0.2 and 70 days for 34,030 (25.6%) of the 133,030 main-sequence Kepler targets (excluding known eclipsing binaries and Kepler Objects of Interest), making this the largest sample of stellar rotation periods to date. In this paper we consider the detailed features of the now well-populated period-temperature distribution and demonstrate that the period bimodality, first seen by McQuillan et al. in the M-dwarf sample, persists to higher masses, becoming less visible above 0.6 M {sub ☉}. We show that these results are globally consistent with the existing ground-based rotation-period data and find that the upper envelope of the period distribution is broadly consistent with a gyrochronological age of 4.5 Gyr, based on the isochrones of Barnes, Mamajek, and Hillenbrand and Meibom et al. We also performed a detailed comparison of our results to those of Reinhold et al. and Nielsen et al., who measured rotation periods of field stars observed by Kepler. We examined the amplitude of periodic variability for the stars with detection rotation periods, and found a typical range between ∼950 ppm (5th percentile) and ∼22,700 ppm (95th percentile), with a median of ∼5600 ppm. We found typically higher amplitudes for shorter periods and lower effective temperatures, with an excess of low-amplitude stars above ∼5400 K.

  1. Birth order effect on childhood food allergy.

    PubMed

    Kusunoki, Takashi; Mukaida, Kumiko; Morimoto, Takeshi; Sakuma, Mio; Yasumi, Takahiro; Nishikomori, Ryuta; Heike, Toshio

    2012-05-01

    Higher birth order is associated with a smaller risk of allergy (birth order effect). The purpose of this study was to compare the significance of the birth order effect on the prevalence of specific allergic diseases [bronchial asthma (BA), atopic dermatitis (AD), allergic rhinitis (AR), allergic conjunctivitis (AC), and food allergy (FA)] among schoolchildren. A questionnaire survey dealing with the prevalence of allergic diseases was administered to the parents of 14,669 schoolchildren aged 7-15 yr. Based on the data, the prevalence of each allergic disease was compared according to birth order (1st, 2nd, and 3rd or later). Multiple regression analysis was performed to test the significance of the differences. There was no significant difference in the prevalence of BA or AD according to birth order. The prevalence of AR, AC, and FA decreased significantly as birth order increased. The prevalence of FA among those with 1st, 2nd, and 3rd or later birth order was 4.0%, 3.4%, and 2.6%, respectively (p = 0.01). With respect to symptoms in infancy, the prevalence of wheeze increased significantly and that of FA and eczema in infancy decreased significantly as birth order increased. The present data show a significant birth order effect on FA. The effect was also observed for the prevalence of FA and eczema in infancy. These data support the concept of early, non-allergen-specific programming of IgE-mediated immunity.

  2. PREFACE: 1st Nano-IBCT Conference 2011 - Radiation Damage of Biomolecular Systems: Nanoscale Insights into Ion Beam Cancer Therapy

    NASA Astrophysics Data System (ADS)

    Huber, Bernd A.; Malot, Christiane; Domaracka, Alicja; Solov'yov, Andrey V.

    2012-07-01

    The 1st Nano-IBCT Conference entitled 'Radiation Damage in Biomolecular Systems: Nanoscale Insights into Ion Beam Cancer Therapy' was held in Caen, France, in October 2011. The Meeting was organised in the framework of the COST Action MP1002 (Nano-IBCT) which was launched in December 2010 (http://fias.uni-frankfurt.de/nano-ibct). This action aims to promote the understanding of mechanisms and processes underlying the radiation damage of biomolecular systems at the molecular and nanoscopic level and to use the findings to improve the strategy of Ion Beam Cancer Therapy. In the hope of achieving this, participants from different disciplines were invited to represent the fields of physics, biology, medicine and chemistry, and also included those from industry and the operators of hadron therapy centres. Ion beam therapy offers the possibility of excellent dose localization for treatment of malignant tumours, minimizing radiation damage in normal healthy tissue, while maximizing cell killing within the tumour. Several ion beam cancer therapy clinical centres are now operating in Europe and elsewhere. However, the full potential of such therapy can only be exploited by better understanding the physical, chemical and biological mechanisms that lead to cell death under ion irradiation. Considering a range of spatio-temporal scales, the proposed action therefore aims to combine the unique experimental and theoretical expertise available within Europe to acquire greater insight at the nanoscopic and molecular level into radiation damage induced by ion impact. Success in this endeavour will be both an important scientific breakthrough and give great impetus to the practical improvement of this innovative therapeutic technique. Ion therapy potentially provides an important advance in cancer therapy and the COST action MP1002 will be very significant in ensuring Europe's leadership in this field, providing the scientific background, required data and mechanistic insight which

  3. Autocorrelation and relaxation time measurements on metal oxide core: dielectric shell beads in an optical trap

    NASA Astrophysics Data System (ADS)

    Iyengar, Shruthi S.; Parthasarathi, Praveen; Selvan, Rekha; Bhattacharya, Sarbari; Ananthamurthy, Sharath

    2016-04-01

    Optical Tweezers are capable of trapping individual particles of sizes that range from micrometers to sub micrometers. One can compute the trap strength experienced by a particle by analyzing the fluctuations in the position of the trapped particle with time. It is reported that the trap strength of a dielectric bead increases linearly with increase in the power of the trapping laser. The situation with metallic particles, however, is strongly dependent on the particle size. Available literature shows that metallic Rayleigh particles experience enhanced trap strengths when compared to dielectric particles of similar sizes due to a larger polarizability. On the contrary, micrometer sized metallic particles are poor candidates for trapping due to high reflectivity. We report here that commercially available micrometer sized metal oxide core - dielectric shell (core - shell) beads are trapped in a single beam optical tweezer in a manner similar to dielectric beads. However as the laser power is increased these core - shell beads are trapped with a reduced corner frequency, which represents a lowered trap strength, in contrast to the situation with ordinary dielectric beads. We attribute this anomaly to an increase in the temperature of the medium in the vicinity of the core - shell bead due to an enhanced dissipation of the laser power as heat. We have computed autocorrelation functions for both types of beads at various trapping laser powers and observe that the variation in the relaxation times with laser power for core - shell beads is opposite in trend to that of ordinary dielectric beads. This supports our claim of an enhanced medium temperature about the trapped core - shell bead. Since an increase in temperature should lead to a change in the local viscosity of the medium, we have estimated the ratio of viscosity to temperature for core - shell and dielectric beads of the same size. We observe that while for ordinary dielectric beads this ratio remains a

  4. Auto-correlation of journal impact factor for consensus research reporting statements: a cohort study.

    PubMed

    Shanahan, Daniel R

    2016-01-01

    journal in which a reporting statement was published was shown to influence the number of citations that statement will gather over time. Similarly, the number of article accesses also influenced the number of citations, although to a lesser extent than the impact factor. This demonstrates that citation counts are not purely a reflection of scientific merit and the impact factor is, in fact, auto-correlated.

  5. Characterizing tissue microstructure using an ultrasound system-independent spatial autocorrelation function

    NASA Astrophysics Data System (ADS)

    Dong, Fang

    1999-09-01

    The research described in this dissertation is related to characterization of tissue microstructure using a system- independent spatial autocorrelation function (SAF). The function was determined using a reference phantom method, which employed a well-defined ``point- scatterer'' reference phantom to account for instrumental factors. The SAF's were estimated for several tissue-mimicking (TM) phantoms and fresh dog livers. Both phantom tests and in vitro dog liver measurements showed that the reference phantom method is relatively simple and fairly accurate, providing the bandwidth of the measurement system is sufficient for the size of the scatterer being involved in the scattering process. Implementation of this method in clinical scanner requires that distortions from patient's body wall be properly accounted for. The SAF's were estimated for two phantoms with body-wall-like distortions. The experimental results demonstrated that body wall distortions have little effect if echo data are acquired from a large scattering volume. One interesting application of the SAF is to form a ``scatterer size image''. The scatterer size image may help providing diagnostic tools for those diseases in which the tissue microstructure is different from the normal. Another method, the BSC method, utilizes information contained in the frequency dependence of the backscatter coefficient to estimate the scatterer size. The SAF technique produced accurate scatterer size images of homogeneous TM phantoms and the BSC method was capable of generating accurate size images for heterogeneous phantoms. In the scatterer size image of dog kidneys, the contrast-to-noise-ratio (CNR) between renal cortex and medulla was improved dramatically compared to the gray- scale image. The effect of nonlinear propagation was investigated by using a custom-designed phantom with overlaying TM fat layer. The results showed that the correlation length decreased when the transmitting power increased. The

  6. Future perspectives in melanoma research : Meeting report from the "Melanoma Bridge". Napoli, December 1st-4th 2015.

    PubMed

    Ascierto, Paolo A; Agarwala, Sanjiv; Botti, Gerardo; Cesano, Alessandra; Ciliberto, Gennaro; Davies, Michael A; Demaria, Sandra; Dummer, Reinhard; Eggermont, Alexander M; Ferrone, Soldano; Fu, Yang Xin; Gajewski, Thomas F; Garbe, Claus; Huber, Veronica; Khleif, Samir; Krauthammer, Michael; Lo, Roger S; Masucci, Giuseppe; Palmieri, Giuseppe; Postow, Michael; Puzanov, Igor; Silk, Ann; Spranger, Stefani; Stroncek, David F; Tarhini, Ahmad; Taube, Janis M; Testori, Alessandro; Wang, Ena; Wargo, Jennifer A; Yee, Cassian; Zarour, Hassane; Zitvogel, Laurence; Fox, Bernard A; Mozzillo, Nicola; Marincola, Francesco M; Thurin, Magdalena

    2016-11-15

    The sixth "Melanoma Bridge Meeting" took place in Naples, Italy, December 1st-4th, 2015. The four sessions at this meeting were focused on: (1) molecular and immune advances; (2) combination therapies; (3) news in immunotherapy; and 4) tumor microenvironment and biomarkers. Recent advances in tumor biology and immunology has led to the development of new targeted and immunotherapeutic agents that prolong progression-free survival (PFS) and overall survival (OS) of cancer patients. Immunotherapies in particular have emerged as highly successful approaches to treat patients with cancer including melanoma, non-small cell lung cancer (NSCLC), renal cell carcinoma (RCC), bladder cancer, and Hodgkin's disease. Specifically, many clinical successes have been using checkpoint receptor blockade, including T cell inhibitory receptors such as cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) and the programmed cell death-1 (PD-1) and its ligand PD-L1. Despite demonstrated successes, responses to immunotherapy interventions occur only in a minority of patients. Attempts are being made to improve responses to immunotherapy by developing biomarkers. Optimizing biomarkers for immunotherapy could help properly select patients for treatment and help to monitor response, progression and resistance that are critical challenges for the immuno-oncology (IO) field. Importantly, biomarkers could help to design rational combination therapies. In addition, biomarkers may help to define mechanism of action of different agents, dose selection and to sequence drug combinations. However, biomarkers and assays development to guide cancer immunotherapy is highly challenging for several reasons: (i) multiplicity of immunotherapy agents with different mechanisms of action including immunotherapies that target activating and inhibitory T cell receptors (e.g., CTLA-4, PD-1, etc.); adoptive T cell therapies that include tissue infiltrating lymphocytes (TILs), chimeric antigen receptors (CARs), and

  7. Three-dimensional analysis of the distal movement of maxillary 1st molars in patients fitted with mini-implant-aided trans-palatal arches

    PubMed Central

    Miresmaeili, Amirfarhang; Sajedi, Ahmad; Moghimbeigi, Abbas

    2015-01-01

    Objective The aim of this study was to investigate three-dimensional molar displacement after distalization via miniscrews and a horizontal modification of the trans-palatal-arch (TPA). Methods The subjects in this clinical trial were 26 Class II patients. After the preparation of a complete set of diagnostic records, miniscrews were inserted between the maxillary 2nd premolar and 1st molar on the palatal side. Elastic modules connected to the TPA exerting an average force of 150-200 g/side parallel to the occlusal plane were applied. Cone-beam computed tomography was utilized to evaluate the position of the miniscrews relative to the adjacent teeth and maxillary sinus, and the direction of force relative to molar furcation. The distances from the central point of the incisive papilla to the mesiopalatal cusps of the 1st maxillary molars and the distances between the mesiopalatal cusps of the left and right molars were measured to evaluate displacement of the maxillary molars on the horizontal plane. Interocclusal space was used to evaluate vertical changes. Results Mean maxillary 1st molar distalization was 2.3 ± 1.1 mm, at a rate of 0.4 ± 0.2 mm/month, and rotation was not significant. Intermolar width increased by 2.9 ± 1.8 mm. Molars were intruded relative to the neighboring teeth, from 0.1 to 0.8 mm. Conclusions Distalization of molars was possible without extrusion, using the appliance investigated. The intrusive component of force reduced the rate of distal movement. PMID:26445718

  8. Characterization of the 1st and 2nd EF-hands of NADPH oxidase 5 by fluorescence, isothermal titration calorimetry, and circular dichroism

    PubMed Central

    2012-01-01

    Background Superoxide generated by non-phagocytic NADPH oxidases (NOXs) is of growing importance for physiology and pathobiology. The calcium binding domain (CaBD) of NOX5 contains four EF-hands, each binding one calcium ion. To better understand the metal binding properties of the 1st and 2nd EF-hands, we characterized the N-terminal half of CaBD (NCaBD) and its calcium-binding knockout mutants. Results The isothermal titration calorimetry measurement for NCaBD reveals that the calcium binding of two EF-hands are loosely associated with each other and can be treated as independent binding events. However, the Ca2+ binding studies on NCaBD(E31Q) and NCaBD(E63Q) showed their binding constants to be 6.5 × 105 and 5.0 × 102 M-1 with ΔHs of -14 and -4 kJ/mol, respectively, suggesting that intrinsic calcium binding for the 1st non-canonical EF-hand is largely enhanced by the binding of Ca2+ to the 2nd canonical EF-hand. The fluorescence quenching and CD spectra support a conformational change upon Ca2+ binding, which changes Trp residues toward a more non-polar and exposed environment and also increases its α-helix secondary structure content. All measurements exclude Mg2+-binding in NCaBD. Conclusions We demonstrated that the 1st non-canonical EF-hand of NOX5 has very weak Ca2+ binding affinity compared with the 2nd canonical EF-hand. Both EF-hands interact with each other in a cooperative manner to enhance their Ca2+ binding affinity. Our characterization reveals that the two EF-hands in the N-terminal NOX5 are Ca2+ specific. Graphical abstract PMID:22490336

  9. Shared spatial effects on quantitative genetic parameters: accounting for spatial autocorrelation and home range overlap reduces estimates of heritability in wild red deer.

    PubMed

    Stopher, Katie V; Walling, Craig A; Morris, Alison; Guinness, Fiona E; Clutton-Brock, Tim H; Pemberton, Josephine M; Nussey, Daniel H

    2012-08-01

    Social structure, limited dispersal, and spatial heterogeneity in resources are ubiquitous in wild vertebrate populations. As a result, relatives share environments as well as genes, and environmental and genetic sources of similarity between individuals are potentially confounded. Quantitative genetic studies in the wild therefore typically account for easily captured shared environmental effects (e.g., parent, nest, or region). Fine-scale spatial effects are likely to be just as important in wild vertebrates, but have been largely ignored. We used data from wild red deer to build "animal models" to estimate additive genetic variance and heritability in four female traits (spring and rut home range size, offspring birth weight, and lifetime breeding success). We then, separately, incorporated spatial autocorrelation and a matrix of home range overlap into these models to estimate the effect of location or shared habitat on phenotypic variation. These terms explained a substantial amount of variation in all traits and their inclusion resulted in reductions in heritability estimates, up to an order of magnitude up for home range size. Our results highlight the potential of multiple covariance matrices to dissect environmental, social, and genetic contributions to phenotypic variation, and the importance of considering fine-scale spatial processes in quantitative genetic studies.

  10. Stochastic modeling of short-term exposure close to an air pollution source in a naturally ventilated room: an autocorrelated random walk method.

    PubMed

    Cheng, Kai-Chung; Acevedo-Bolton, Viviana; Jiang, Ruo-Ting; Klepeis, Neil E; Ott, Wayne R; Kitanidis, Peter K; Hildemann, Lynn M

    2014-01-01

    For an actively emitting source such as cooking or smoking, indoor measurements have shown a strong "proximity effect" within 1 m. The significant increase in both the magnitude and variation of concentration near a source is attributable to transient high peaks that occur sporadically-and these "microplumes" cause great uncertainty in estimating personal exposure. Recent field studies in naturally ventilated rooms show that close-proximity concentrations are approximately lognormally distributed. We use the autocorrelated random walk method to represent the time-varying directionality of indoor emissions, thereby predicting the time series and frequency distributions of concentrations close to an actively emitting point source. The predicted 5-min concentrations show good agreement with measurements from a point source of CO in a naturally ventilated house-the measured and predicted frequency distributions at 0.5- and 1-m distances are similar and approximately lognormal over a concentration range spanning three orders of magnitude. By including the transient peak concentrations, this random airflow modeling method offers a way to more accurately assess acute exposure levels for cases where well-defined airflow patterns in an indoor space are not available.

  11. Breakdown of the continuum limit approximation to the discrete scattering events and its influence on the electric field autocorrelation functions of transmitted light

    NASA Astrophysics Data System (ADS)

    Šormaz, Miloš; Reufer, Mathias; Völker, Andreas C.; Simon, Klaus

    2014-11-01

    The complexity of modeling light propagation in turbid media can be significantly simplified if one assumes it to be diffusive. This is, however, only valid after the light has traveled a sufficient distance so that the diffusion equation can be employed. So far, there has been no reliable way to determine this distance, despite the fact that the assumption is often applied in optics. The discrete nature of scattering events plays an important role in modeling propagation of weakly scattered light, so a continuum equation such as the diffusion equation cannot be used to describe this process. Electric field autocorrelation functions g1(τ ) of light transmitted through turbid colloidal samples are measured using diffusing wave spectroscopy and compared to Monte Carlo simulations in order to obtain a better estimation of the continuum limit. The two methods to calculate g1(τ ) from the simulated photon trajectories are compared; the first assumes the continuum limit by using the path-length distributions of photon trajectories, while the second considers the square momentum transfers and therefore accurately calculates g1(τ ) even if the detected signal is composed of weakly scattered light. The results of the two methods are used to determine the lengths of the shortest diffuse photon trajectories; they grow with the sample thickness and scattering anisotropy.

  12. Moral Judgment and Its Relation to Second-Order Theory of Mind

    ERIC Educational Resources Information Center

    Fu, Genyue; Xiao, Wen S.; Killen, Melanie; Lee, Kang

    2014-01-01

    Recent research indicates that moral judgment and 1st-order theory of mind abilities are related. What is not known, however, is how 2nd-order theory of mind is related to moral judgment. In the present study, we extended previous findings by administering a morally relevant theory of mind task (an accidental transgressor) to 4- to 7-year-old…

  13. Study of the non-linear autocorrelations within the Gaussian regime

    NASA Astrophysics Data System (ADS)

    Kutner, R.; Świtała, F.

    2003-06-01

    defined by the spatial and temporal fractional dimensions of the walking state. To adapt the model to the description of empirical data (or discrete time series) which are collected with a discrete time-step we used in the continuous-time series produced by the model a discretization procedure. We observed that such a procedure generates, in general, long-range non-linear autocorrelations even in the Gaussian regime, which appear to be similar to those observed, e.g., in the financial time series [3 6], although single steps of the walker within continuous time are, by definition, uncorrelated. This suggests a surprising explanation alternative to the one proposed very recently ( cf. [7] and Refs. therein) although both approaches involve related variants of the well-known CTRW formalism applied yet in many different branches of knowledge [8 10].

  14. COERC 2002: Appreciating Scholarship. Proceedings of the Annual College of Education Research Conference (1st, Miami, Florida, April 27, 2002).

    ERIC Educational Resources Information Center

    Nielsen, Sarah M., Ed.; Rocco, Tonette S., Ed.

    This conference was designed to offer a view to novice scholars of what scholarship is and provide insights on how to share knowledge with others. The keynote speech by Lisa Delpit, "The Role of Scholarship," is not included in this volume. Other conference papers, presented in alphabetical order by first author, include: (1) "Social Studies in…

  15. Weather Education. Proceedings of the International Conference on School and Popular Meteorological Education (1st, Oxford, England, July 1984).

    ERIC Educational Resources Information Center

    Walker, J. M., Ed.

    The First International Conference on School and Popular Meteorological Education was designed to: (1) examine the need for the general public to be educated in science and mathematics in order to live in today's high technological society; (2) note special attributes that meteorology possesses as a vehicle to teach science and mathematics to all…

  16. Autocorrelation measurement of femtosecond laser pulses based on two-photon absorption in GaP photodiode

    SciTech Connect

    Chong, E. Z.; Watson, T. F.; Festy, F.

    2014-08-11

    Semiconductor materials which exhibit two-photon absorption characteristic within a spectral region of interest can be useful in building an ultra-compact interferometric autocorrelator. In this paper, we report on the evidence of a nonlinear absorption process in GaP photodiodes which was exploited to measure the temporal profile of femtosecond Ti:sapphire laser pulses with a tunable peak wavelength above 680 nm. The two-photon mediated conductivity measurements were performed at an average laser power of less than a few tenths of milliwatts. Its suitability as a single detector in a broadband autocorrelator setup was assessed by investigating the nonlinear spectral sensitivity bandwidth of a GaP photodiode. The highly favourable nonlinear response was found to cover the entire tuning range of our Ti:sapphire laser and can potentially be extended to wavelengths below 680 nm. We also demonstrated the flexibility of GaP in determining the optimum compensation value of the group delay dispersion required to restore the positively chirped pulses inherent in our experimental optical system to the shortest pulse width possible. With the rise in the popularity of nonlinear microscopy, the broad two-photon response of GaP and the simplicity of this technique can provide an alternative way of measuring the excitation laser pulse duration at the focal point of any microscopy systems.

  17. Non-invasive in vivo measurement of the tear film using spatial autocorrelation in a live mammal model

    PubMed Central

    Azartash, Kaveh; Shy, Chyong-jy Nein; Flynn, Kevin; Jester, James V.; Gratton, Enrico

    2010-01-01

    Tear film stability and its interaction with the corneal surface play an important role in maintaining ocular surface integrity and quality of vision. We present a non-invasive technique to quantify the pre-corneal tear film thickness. A cMOS camera is used to record the interference pattern produced by the reflections from multiple layers of the tear film Principles of spatial autocorrelation are applied to extract the frequency of the periodic patterns in the images. A mathematical model is developed to obtain the thickness of the tear film from the spatial autocorrelation image. The technique is validated using micro-fabricated thin parylene films. We obtained repeatable and precise measurement on a live rabbit model (N = 6). We obtained an average value of 10.2µm and standard deviation of, SD = 0.3 (N = 4). We measured one rabbit infected with HSV-1 virus that had a baseline tear film thickness of 4.7µm. PMID:21258535

  18. Real-time autocorrelator for fluorescence correlation spectroscopy based on graphical-processor-unit architecture: method, implementation, and comparative studies

    NASA Astrophysics Data System (ADS)

    Laracuente, Nicholas; Grossman, Carl

    2013-03-01

    We developed an algorithm and software to calculate autocorrelation functions from real-time photon-counting data using the fast, parallel capabilities of graphical processor units (GPUs). Recent developments in hardware and software have allowed for general purpose computing with inexpensive GPU hardware. These devices are more suited for emulating hardware autocorrelators than traditional CPU-based software applications by emphasizing parallel throughput over sequential speed. Incoming data are binned in a standard multi-tau scheme with configurable points-per-bin size and are mapped into a GPU memory pattern to reduce time-expensive memory access. Applications include dynamic light scattering (DLS) and fluorescence correlation spectroscopy (FCS) experiments. We ran the software on a 64-core graphics pci card in a 3.2 GHz Intel i5 CPU based computer running Linux. FCS measurements were made on Alexa-546 and Texas Red dyes in a standard buffer (PBS). Software correlations were compared to hardware correlator measurements on the same signals. Supported by HHMI and Swarthmore College

  19. Autocorrelation measurement of femtosecond laser pulses based on two-photon absorption in GaP photodiode

    NASA Astrophysics Data System (ADS)

    Chong, E. Z.; Watson, T. F.; Festy, F.

    2014-08-01

    Semiconductor materials which exhibit two-photon absorption characteristic within a spectral region of interest can be useful in building an ultra-compact interferometric autocorrelator. In this paper, we report on the evidence of a nonlinear absorption process in GaP photodiodes which was exploited to measure the temporal profile of femtosecond Ti:sapphire laser pulses with a tunable peak wavelength above 680 nm. The two-photon mediated conductivity measurements were performed at an average laser power of less than a few tenths of milliwatts. Its suitability as a single detector in a broadband autocorrelator setup was assessed by investigating the nonlinear spectral sensitivity bandwidth of a GaP photodiode. The highly favourable nonlinear response was found to cover the entire tuning range of our Ti:sapphire laser and can potentially be extended to wavelengths below 680 nm. We also demonstrated the flexibility of GaP in determining the optimum compensation value of the group delay dispersion required to restore the positively chirped pulses inherent in our experimental optical system to the shortest pulse width possible. With the rise in the popularity of nonlinear microscopy, the broad two-photon response of GaP and the simplicity of this technique can provide an alternative way of measuring the excitation laser pulse duration at the focal point of any microscopy systems.

  20. Influence to 16-QAM of CATV using the third-order pumped distributed Raman amplifier

    NASA Astrophysics Data System (ADS)

    Wang, Qin; Gao, Ying; Huang, Shaoling; Cao, Jing

    2013-12-01

    In order to study the practical applicabality of the 3rd-order distributed Raman amplifier (DRA) in Cable Antenna Television (CATV) system, the structure of the 3rd-order DRA is put forward firstly, and the effect of higher order simulated Raman scattering is investigated. Moreover a simulated 3rdorder DRA-CATV system over 120 km fiber is set up to study its performance of 16-QAM as the main digital signal. In order to compare the performances, a simulated 1st-order DRA-CATV system is also set up. Simulation results indicate that the bit error rate (BER) of 16-QAM in the 3rd-order DRACATV system is lower than that in the 1st-order DRA-CATV system. The theory results are beneficial to apply a higher-order Raman pumping (HOP) DRA for the future experiment.

  1. Spatial scale of autocorrelation of assemblages of benthic invertebrates in two upland rivers in South-Eastern Australia and its implications for biomonitoring and impact assessment in streams.

    PubMed

    Lloyd, Natalie J; Nally, Ralph Mac; Lake, P S

    2006-04-01

    Spatial autocorrelation in ecological systems is a critical issue for monitoring (and a general understanding of ecological dynamics) yet there are very few data available, especially for riverine systems. Here, we report here on assemblage-level autocorrelation in the benthic-invertebrate assemblages of riffles in two adjacent, relatively pristine rivers in south-eastern Victoria, Australia (40-km reaches of the Wellington [surveys in summers of 1996 and 1997] and Wonnangatta Rivers [survey in summer of 1996 only], with 16 sites in each river). We found that analyses were similar if the data were resolved to family or to species level. Spatial autocorrelation was assessed by using Mantel-tests for the data partitioned into different sets of spatial separations of survey sites (e.g. 0-6 km, 6-12 km, etc.). We found strong small-scale (< or =6 km) autocorrelation in the Wellington River, which is consistent with known dispersal abilities of many aquatic invertebrates. Surprisingly, there were strong negative correlations at longer distance classes for the Wellington River in one of the two summers (20-40 km) and the Wonnangatta River (12-20 km). That two largely unimpacted, adjacent rivers should have such different autocorrelation patterns suggests that impact assessment cannot assume dependence or independence of sites a priori. We discuss the implications of these results for use of "reference" sites to assess impacts at nominally affected sites.

  2. Effect of milk feed source, frequency of feeding and age at turnout on calf performance, live-weight at mating and 1st lactation milk production

    PubMed Central

    2012-01-01

    Female calves (n = 108) were assigned to 6 cold milk feeding treatments in two experiments for a 70-day period. Live-weight (LW) was measured weekly, with an additional LW taken at day 410 and post-calving for animals in experiment 1. In Experiment 1, the effect of feeding frequency and age of turnout to pasture on calf performance and 1st lactation milk yields were evaluated. The whole milk (WM) feeding treatments applied were (i) once daily feeding (OD), (ii) twice daily feeding (TD), (iii) OD feeding, outdoors at 38 days (ODO). In Experiment 2, the effects of feeding milk replacer (MR) as opposed to WM and age of turnout to pasture on calf performance were evaluated. The treatments applied were (i) OD feeding with WM (OD), (ii) OD feeding with milk replacer (MR) (ODMR), (iii) OD feeding with MR, outdoors at 38 days (ODMRO). Experiment 1: There were no differences (P > 0.05) in LW or average daily gain between TD and OD calves at day 80 or 410. ODO calves had lower LW at day 80 as compared to OD or TD (P < 0.001). Calf LW at day 80 was 86, 89 and 85 kg and at day 410 was 304, 309 and 316 kg for OD, TD and ODO, respectively. Milk feeding frequency or time of calf turnout had no effect on LW post calving, milk composition or 1st lactation milk yields. Experiment 2: Total LW at day 80 was higher (P < 0.05) for ODMR compared to OD or ODMRO calves. Calf LW was 87, 95, and 88 kg for OD, ODMR and ODMRO, respectively. However, LW at day 410 did not differ between treatments. This study showed that while some differences were observed in calf LW at day 80, these differences had no effect on LW at day 410 or 1st lactation milk yield. It can be concluded that calves can be successfully reared when fed OD with WM or MR, indoors and when turned out to pasture at 38 days of age. PMID:23078871

  3. Joint U.S./Japan Conference on Adaptive Structures, 1st, Maui, HI, Nov. 13-15, 1990, Proceedings

    NASA Astrophysics Data System (ADS)

    Wada, Ben K.; Fanson, James L.; Miura, Koryo

    1991-11-01

    The present volume of adaptive structures discusses the development of control laws for an orbiting tethered antenna/reflector system test scale model, the sizing of active piezoelectric struts for vibration suppression on a space-based interferometer, the control design of a space station mobile transporter with multiple constraints, and optimum configuration control of an intelligent truss structure. Attention is given to the formulation of full state feedback for infinite order structural systems, robustness issues in the design of smart structures, passive piezoelectric vibration damping, shape control experiments with a functional model for large optical reflectors, and a mathematical basis for the design optimization of adaptive trusses in precision control. Topics addressed include approaches to the optimal adaptive geometries of intelligent truss structures, the design of an automated manufacturing system for tubular smart structures, the Sandia structural control experiments, and the zero-gravity dynamics of space structures in parabolic aircraft flight.

  4. Joint U.S./Japan Conference on Adaptive Structures, 1st, Maui, HI, Nov. 13-15, 1990, Proceedings

    NASA Technical Reports Server (NTRS)

    Wada, Ben K. (Editor); Fanson, James L. (Editor); Miura, Koryo (Editor)

    1991-01-01

    The present volume of adaptive structures discusses the development of control laws for an orbiting tethered antenna/reflector system test scale model, the sizing of active piezoelectric struts for vibration suppression on a space-based interferometer, the control design of a space station mobile transporter with multiple constraints, and optimum configuration control of an intelligent truss structure. Attention is given to the formulation of full state feedback for infinite order structural systems, robustness issues in the design of smart structures, passive piezoelectric vibration damping, shape control experiments with a functional model for large optical reflectors, and a mathematical basis for the design optimization of adaptive trusses in precision control. Topics addressed include approaches to the optimal adaptive geometries of intelligent truss structures, the design of an automated manufacturing system for tubular smart structures, the Sandia structural control experiments, and the zero-gravity dynamics of space structures in parabolic aircraft flight.

  5. Spatial autocorrelation in the response of soft-bottom marine benthos to gas extraction activities: the case of amphipods in the Ionian Sea.

    PubMed

    Fiorentino, Dario; Caruso, Tancredi; Terlizzi, Antonio

    2012-08-01

    The spatial distributions of marine fauna and of pollution are both highly structured, and thus the resulting high levels of autocorrelation may invalidate conclusions based on classical statistical approaches. Here we analyse the close correlation observed between proxies for the disturbance associated with gas extraction activities and amphipod distribution patterns around four hydrocarbon platforms. We quantified the amount of variation independently accounted for by natural environmental variables, proxies for the disturbance caused by platforms, and spatial autocorrelation. This allowed us to demonstrate how each of these three factors significantly affects the community structure of amphipods. Sophisticated statistical techniques are required when taking into account spatial autocorrelation; nevertheless our data demonstrate that this approach not only enables the formulation of robust statistical inferences but also provides a much deeper understanding of the subtle interactions between human disturbance and natural factors affecting the structure of marine invertebrates communities.

  6. Spatial epidemiology in zoonotic parasitic diseases: insights gained at the 1st International Symposium on Geospatial Health in Lijiang, China, 2007

    PubMed Central

    Zhou, Xiao-Nong; Lv, Shan; Yang, Guo-Jing; Kristensen, Thomas K; Bergquist, N Robert; Utzinger, Jürg; Malone, John B

    2009-01-01

    The 1st International Symposium on Geospatial Health was convened in Lijiang, Yunnan province, People's Republic of China from 8 to 9 September, 2007. The objective was to review progress made with the application of spatial techniques on zoonotic parasitic diseases, particularly in Southeast Asia. The symposium featured 71 presentations covering soil-transmitted and water-borne helminth infections, as well as arthropod-borne diseases such as leishmaniasis, malaria and lymphatic filariasis. The work made public at this occasion is briefly summarized here to highlight the advances made and to put forth research priorities in this area. Approaches such as geographical information systems (GIS), global positioning systems (GPS) and remote sensing (RS), including spatial statistics, web-based GIS and map visualization of field investigations, figured prominently in the presentation. PMID:19193214

  7. JANNAF 25th Airbreathing Propulsion Subcommittee, 37th Combustion Subcommittee and 1st Modeling and Simulation Subcommittee Joint Meeting. Volume 1

    NASA Technical Reports Server (NTRS)

    Fry, Ronald S.; Becker, Dorothy L.

    2000-01-01

    Volume I, the first of three volumes, is a compilation of 24 unclassified/unlimited-distribution technical papers presented at the Joint Army-Navy-NASA-Air Force (JANNAF) 25th Airbreathing Propulsion Subcommittee, 37th Combustion Subcommittee and 1st Modeling and Simulation Subcommittee (MSS) meeting held jointly with the 19th Propulsion Systems Hazards Subcommittee. The meeting was held 13-17 November 2000 at the Naval Postgraduate School and Hyatt Regency Hotel, Monterey, California. Topics covered include: a Keynote Address on Future Combat Systems, a review of the new JANNAF Modeling and Simulation Subcommittee, and technical papers on Hyper-X propulsion development and verification; GTX airbreathing launch vehicles; Hypersonic technology development, including program overviews, fuels for advanced propulsion, ramjet and scramjet research, hypersonic test medium effects; and RBCC engine design and performance, and PDE and UCAV advanced and combined cycle engine technologies.

  8. 1(st) EMBL/DFG Women in Science Network Conference Heidelberg 2016: From Genes, Cells and the Immune System towards Therapies - Meeting Report.

    PubMed

    Stripecke, Renata; Gouttefangeas, Cécile; Förster, Irmgard

    2016-11-01

    The 1(st) EMBL/DFG Women in Science (WiS) Conference "From Genes, Cells and the Immune System towards Therapies" was held on 19(th) - 20(th) September 2016 in Heidelberg, Germany. The WiS conference was funded by nine Collaborative Research Centers (CRCs) of the German Research Council (Deutsche Forschungsgemeinschaft, DFG; Table 1) and benefited from an outstanding hosting environment at the Advanced Training Center of the European Molecular Biology Laboratory (EMBL). Scientific talks focused at genetic, cellular and immunologic mechanisms, and immune therapy, and progress from all stages of development covering basic research to clinical developments was described. The presentations were embedded between structured networking sessions and a round table discussion with representatives of the DFG, EMBL, European Molecular Biology Organisation (EMBO), and the German Society of Immunology (DGfI).

  9. [State of the reproductive systemin in male rats of 1st generation obtained from irradiated parents and exposed to electromagnetic radiation (897 MHz) during embryogenesis and postnatal development].

    PubMed

    Vereshchako, G G; Chueshova, N V; Gorokh, G A; Naumov, A D

    2014-01-01

    The consequences of prolonged exposure to electromagnetic radiation from cellular phone (897 MHz, daily 8 h/day) in male rats of the 1st generation obtained from irradiated parents and subjected to prolonged exposure to electromagnetic radiation of the range of mobile communications during ontogeny and postnatal development were studied. It has been found that irradiation causes a decrease in the number of births of animals, changing the sex ratio towards the increase in the number of males. It had a significant impact on the reproductive system of males, accelerating their sexual development, revealed at the age of two months. Radiation from cell phones led to significant disproportions in the cell number at different stages of spermatogenesis. It increased the number of mature spermatozoa which decreased viability.

  10. 1st International Symposium on Gait and Balance in MS: Gait and Balance Measures in the Evaluation of People with MS

    PubMed Central

    Cameron, Michelle; Wagner, Joanne; Zackowski, Kathleen; Spain, Rebecca

    2012-01-01

    Gait and balance measures have particular potential as outcome measures in Multiple Sclerosis (MS) because, of the many hallmarks of MS disability, gait and balance dysfunction are present throughout the course of the disease, impact many aspects of a person's life, and progress over time. To highlight the importance and relevance of gait and balance measures in MS, explore novel measurements of gait and balance in MS, and discuss how gait, balance, and fall measures can best be used and developed in clinical and research settings, the 1st International Symposium on Gait and Balance in Multiple Sclerosis was held in Portland, Oregon, USA on October 1, 2011. This meeting brought together nearly 100 neurologists, physiatrists, physical therapists, occupational therapists, nurses, engineers, and others to discuss the current status and recent advances in the measurement of gait and balance in MS. Presentations focused on clinician-administered, self-administered, and instrumented measures of gait, balance, and falls in MS. PMID:22762000

  11. Hydrocarbon-oil encapsulated air bubble flotation of fine coal. 1st Quarterly report, October 1, 1990--December 31, 1990

    SciTech Connect

    Peng, F.F.

    1995-01-01

    In the froth flotation process, whether accomplished In a conventional stirred tank flotation cell, in a column flotation cell, in an air sparged cyclone flotation or in a static-tube cell by using microbubbles, it requires the addition of large quantity of surfactants such as frother and/or collector (or promoter). In coarse coal flotation, special reagents are used such as high molecular weight frothers, the collector with a non-ionic, low foam emulsifier, Sherex Shur Coal 159 or Sherex Shur Coal 168 blended with fuel oil No. 2. These reagents in liquid forms are directly added into the coal pulp in the flotation cell. Frequently, a conditioning tank is required to achieve the dispersion of the reagents. The dispersion of the collector such as hydrocarbon-oil (insoluble or partially soluble) by a mechanical mixer in the coal pulp is often inadequate. In this work, in order to demonstrate the effectiveness of collector droplet size and dispersion on froth flotation processes, a unique gasified collector dispersion and oil-coated bubble generation system was used. The hydrocarbon oil collector was gasified at a temperature approximately 40 degrees C above the fractionation temperature of the collector to avoid pyrolysis. Gasified collector is first mixed in the air stream and transported to the air diffusion hood in the flotation cell. The oil-coated air bubbles were then generated and diffused into solid-water phases.

  12. Variation of the intensity of the Earth's magnetic field in Portugal in the 1st millennium BC

    NASA Astrophysics Data System (ADS)

    Nachasova, I. E.; Burakov, K. S.

    2009-07-01

    The study of magnetization of the ceramic material from 21 archeological monuments of Portugal (the Evora province), dated archeologically from the Bronze Age to the end of the Iron Age has been carried out. For the purpose of more detailed timing of the material from the monuments the method of ceramic age dating on the basis of its porosity has been used. In order to take into account the distorted factors in the determination of the parameters of the ancient geomagnetic field with the aim of the maximal approximation to the actual values the diagnostic features of magnetite weathering have been considered and the level of weathering of the magnetic fraction in the ceramics from archeological monuments has been determined. The data of geomagnetic field-strength variation in the time interval of the 12th century BC to the beginning of the Common Era have been obtained. The field-strength at this time interval varied in the range of 60-90 micro Tesla with the maximal values in the 9th, 8th, and the second half of the 5th to the beginning of the 4th century BC. In addition, the timing of the ceramic material from the urns of the megalithic complex Monte de Tera of the Evora province has been clarified.

  13. Preparing for introduction of a dengue vaccine: recommendations from the 1st Dengue v2V Asia-Pacific Meeting.

    PubMed

    Lam, Sai Kit; Burke, Donald; Capeding, Maria Rosario; Chong, Chee Keong; Coudeville, Laurent; Farrar, Jeremy; Gubler, Duane; Hadinegoro, Sri Rezeki; Hanna, Jeffrey; Lang, Jean; Lee, Han Lim; Leo, Yee Sin; Luong, Chan Quang; Mahoney, Richard; McBride, John; Mendez-Galvan, Jorge; Ng, Lee Ching; Nimmannitya, Suchitra; Ooi, Eng Eong; Shepard, Donald; Smit, Jaco; Teyssou, Rémy; Thomas, Laurent; Torresi, Joseph; Vasconcelos, Pedro; Wirawan, Dewa Nyoman; Yoksan, Sutee

    2011-11-28

    Infection with dengue virus is a major public health problem in the Asia-Pacific region and throughout tropical and sub-tropical regions of the world. Vaccination represents a major opportunity to control dengue and several candidate vaccines are in development. Experts in dengue and in vaccine introduction gathered for a two day meeting during which they examined the challenges inherent to the introduction of a dengue vaccine into the national immunisation programmes of countries of the Asia-Pacific. The aim was to develop a series of recommendations to reduce the delay between vaccine licensure and vaccine introduction. Major recommendations arising from the meeting included: ascertaining and publicising the full burden and cost of dengue; changing the perception of dengue in non-endemic countries to help generate global support for dengue vaccination; ensuring high quality active surveillance systems and diagnostics; and identifying sustainable sources of funding, both to support vaccine introduction and to maintain the vaccination programme. The attendees at the meeting were in agreement that with the introduction of an effective vaccine, dengue is a disease that could be controlled, and that in order to ensure a vaccine is introduced as rapidly as possible, there is a need to start preparing now.

  14. Superacid Catalyzed Coal Conversion Chemistry. 1st and 2nd Quarterly Technical Progress Reports, September 1, 1983-March 30, 1984.

    DOE R&D Accomplishments Database

    Olah, G. A.

    1984-01-01

    In our laboratories we have previously developed a mild coal conversion process. This involves the use of a superacid system consisting of HF and BF{sub 3} in presence of hydrogen and/or a hydrogen donor solvent. In order to understand the chemistry involved in the process of depolymerization of coal by the HF:BF{sub 3}:H{sub 2} system we are carrying out a systematic study of a number of coal model compounds. The model compounds selected for present study have two benzene rings connected with various bridging units such as alkylidene, ether, sulfide etc. From studies so far carried out it appears that high pyridine extractibilities achieved by treating coal at temperature below 100 degrees C results from the cleavage of bridges such as present in bibenzyl, diphenyl methane, dibenzyl ether, dibenzyl sulfide etc. On the other hand the increased cyclohexane extractibility and distillability observed at relatively higher temperatures and hydrogen pressures reflects the hydrogenation and cleavage of the aromatic backbone in coal structure similar to what is seen in the conversion of model compounds such as biphenyl, diphenyl ether, diphenyl sulfide, anthracene, etc.

  15. Lengthening osteotomy of the calcaneus and flexor digitorum longus tendon transfer in flexible flatfoot deformity improves talo-1st metatarsal-Index, clinical outcome and pedographic parameter.

    PubMed

    Richter, Martinus; Zech, Stefan

    2013-03-01

    Lengthening osteotomy of the calcaneus (LO) and flexor digitorum longus tendon (FDL) transfer to the navicular is one option for the treatment of flexible flatfoot deformity (FD). The aim of the study was to analyse the amount of correction and clinical outcome including pedographic assessment. In a prospective consecutive non-controlled clinical followup study, all patients with FD that were treated with LO and FDL from September 1st 2006 to August 31st, 2009 were included. Assessment was performed before surgery and at 2-year-followup including clinical examination (with staging of posterior tibialis insufficiency) weight bearing radiographs (Talo-1st metatarsal angles (TMT)), pedography (increased midfoot contact area and force) and Visual Analogue Scale Foot and Ankle (VAS FA). 112 feet in 102 patients were analysed (age, 57.6 (13-82), 42% male). In 12 feet (9%) wound healing delay without further surgical measures was registered. All patients achieved full weight bearing during the 7th postoperative week. Until followup, revision surgery was done in 3 patients (fusion calcaneocuboid joint (n=2), correction triple arthrodesis (n=1)). 101 feet (90%) completed 2-year-followup. TMT dorsoplantar/lateral/Index and VAS FA scores were increased, and posterior tibialis insufficiency stage, pedographic midfoot contact area and force percentage were decreased (each p<.05). All relevant parameters (stage of posterior tibialis insufficiency, TMT angles and Index, pedographic midfoot contact area and force percentage, VAS FA) were improved 2 years after LO and FDL transfer to the navicular in FD. The complication rate was low. This method allows safe and predictable correction.

  16. Higher Cord C-Peptide Concentrations Are Associated With Slower Growth Rate in the 1st Year of Life in Girls but Not in Boys

    PubMed Central

    Regnault, Nolwenn; Botton, Jérémie; Heude, Barbara; Forhan, Anne; Hankard, Régis; Foliguet, Bernard; Hillier, Teresa A.; Souberbielle, Jean-Claude; Dargent-Molina, Patricia; Charles, Marie-Aline

    2011-01-01

    OBJECTIVE To understand the relationships between maternal glycemia during pregnancy and prenatal and early postnatal growth by evaluating cord C-peptide and IGF-I as mediating biomarkers in boys and girls separately. RESEARCH DESIGN AND METHODS We evaluated 342 neonates within the EDEN mother-child cohort study born to mothers without diabetes diagnosis before pregnancy. We measured maternal glycemia at 24–28 weeks of gestation and neonates’ cord blood C-peptide (used as a proxy for fetal insulin) and IGF-I at birth. Reported maternal prepregnancy BMI and all measured infant weights and lengths in the 1st year were recorded. Growth modeling was used to obtain an individual growth curve for each infant in the 1st year. Path models, a type of structural equation modeling, were used for statistical analysis. Path analysis is a multivariate method associated with a graphical display that allows evaluation of mediating factors and distinguishes direct, indirect, and total effects. RESULTS Cord C-peptide at birth was positively correlated with maternal prepregnancy BMI and maternal glycemia and was higher in girls. In a path model that represented prenatal growth, there was no significant direct effect of maternal glycemia on birth weight, but the effect of maternal glycemia on birth weight was mediated by fetal insulin and IGF-I in both girls and boys. However, in girls only, higher concentrations of cord C-peptide (but not cord IGF-I or maternal glucose) were associated with slower weight growth in the first 3 months of life. CONCLUSIONS Our study underlines the role of the fetal insulin–IGF-I axis in the relationship between maternal glycemia during pregnancy and birth weight. We also show for the first time that high insulin concentration in female fetuses is associated with slower early postnatal growth. This slow, early growth pattern may be programmed by fetal hyperinsulinemia, and girls may be more susceptible than boys to its consequences. PMID:21700880

  17. Effect of maternal dietary counselling during the 1st year of life on glucose profile and insulin resistance at the age of 8 years: a randomised field trial.

    PubMed

    Costa, Cintia S; Campagnolo, Paula D B; Lumey, L H; Vitolo, Marcia R

    2017-01-01

    Education interventions that stimulate complementary feeding practices can improve the nutritional status of children and may protect against future chronic diseases. We assessed the long-term effectiveness of dietary intervention during the 1st year of life on insulin resistance levels, and investigated the relationship between insulin resistance and weight changes over time. A randomised field trial was conducted among 500 mothers who gave birth to full-term infants between October 2001 and June 2002 in a low-income area in São Leopoldo, Brazil. Mother-child pairs were randomly assigned to intervention (n 200) and control groups (n 300), and the mothers in the intervention group received dietary counselling on breast-feeding and complementary feeding of their children during the 1st year of life. Fieldworkers blinded to assignment assessed socio-demographic, dietary and anthropometric data during follow-up at ages 1, 4 and 8 years. Blood tests were performed in 305 children aged 8 years to measure fasting serum glucose and insulin concentrations and the homoeostasis model assessment index of insulin resistance (HOMA-IR). At the age of 8 years, the intervention group showed no changes in glucose and insulin concentrations or HOMA-IR values (change 0·07; 95 % CI -0·06, 0·21 for girls; and change -0·07; 95 % CI -0·19, 0·04 for boys) compared with study controls. Insulin resistance was highly correlated, however, with increases in BMI between birth and 8 years of age. Although this dietary intervention had no impact on glucose profile at age 8 years, our findings suggest that BMI changes in early childhood can serve as an effective marker of insulin resistance.

  18. Temporal coherence effects in multiple ionization of N{sub 2} via XUV pump-probe autocorrelation

    SciTech Connect

    Jiang, Y. H.; Pfeifer, T.; Kurka, M.; Kuehnel, K. U.; Schroeter, C. D.; Moshammer, R.; Rudenko, A.; Foucar, L.; Herrwerth, O.; Lezius, M.; Kling, M. F.; Liu, X.; Ueda, K.; Duesterer, S.; Treusch, R.; Ullrich, J.

    2010-10-15

    Using a split-mirror stage combined with a reaction microscope, nonlinear autocorrelation traces of XUV pulses from the Free-electron LASer at Hamburg were recorded for N{sub 2} multiphoton-induced fragmentation into noncoincident N{sup 2+} and coincident N{sup 2+}+N{sup 2+} channels. We find a pulse duration of 40{+-}10 fs along with a sharp spike pointing to a coherence time of 4{+-}1 fs, almost twice as short as in previous observations. Both are well reproduced by a simulation based on the partial-coherence model that includes the molecular dynamics leading to an {approx}12-fs substructure in the trace.

  19. Studies in astronomical time series analysis. III - Fourier transforms, autocorrelation functions, and cross-correlation functions of unevenly spaced data

    NASA Technical Reports Server (NTRS)

    Scargle, Jeffrey D.

    1989-01-01

    This paper develops techniques to evaluate the discrete Fourier transform (DFT), the autocorrelation function (ACF), and the cross-correlation function (CCF) of time series which are not evenly sampled. The series may consist of quantized point data (e.g., yes/no processes such as photon arrival). The DFT, which can be inverted to recover the original data and the sampling, is used to compute correlation functions by means of a procedure which is effectively, but not explicitly, an interpolation. The CCF can be computed for two time series not even sampled at the same set of times. Techniques for removing the distortion of the correlation functions caused by the sampling, determining the value of a constant component to the data, and treating unequally weighted data are also discussed. FORTRAN code for the Fourier transform algorithm and numerical examples of the techniques are given.

  20. The ability of spectrum autocorrelation models to predict the lycopene concentration in foods through visible spectroscopic data.

    PubMed

    Torrecilla, José S; Fernández-Ruiz, Virginia; Cámara, Montaña; Mata, M Cortes Sánchez

    2011-10-15

    We developed a novel computerized approach based on lag-k autocorrelation coefficients (LCCs) and linear models (LMs) to estimate the concentration of lycopene in foods by the spectroscopy. The LCCs were calculated using the data obtained using whole visible scans from 400 to 600 nm (vide supra) of lycopene standards and food samples (ketchup, tomato juice and tomato sauce). The chaotic parameter (CP) was then transferred into a LM to estimate the concentration of lycopene compound. The integrated LCC/visible spectroscopy method developed can be considered as a satisfactory analytical technique able to estimate lycopene concentration in food samples in a fast accurate way, with a mean prediction error lower than 5.7% and a mean correlation coefficient higher than 0.957.

  1. Long-time tail of the velocity autocorrelation function in a two-dimensional moderately dense hard-disk fluid.

    PubMed

    Isobe, Masaharu

    2008-02-01

    Alder and Wainwright discovered the slow power decay ~t(-d/2) (d is dimension) of the velocity autocorrelation function in moderately dense hard-sphere fluids using the event-driven molecular dynamics simulations. In the two-dimensional (2D) case, the diffusion coefficient derived using the time correlation expression in linear response theory shows logarithmic divergence, which is called the "2D long-time-tail problem." We reexamined this problem to perform a large-scale, long-time simulation with 1x10(6) hard disks using a modern efficient algorithm and found that the decay of the long tail in moderately dense fluids is slightly faster than the power decay (~1/t) . We also compared our numerical data with the prediction of the self-consistent mode-coupling theory in the long-time limit [~1/(t sqrt[ln t])] .

  2. Velocity autocorrelation by quantum simulations for direct parameter-free computations of the neutron cross sections. II. Liquid deuterium

    NASA Astrophysics Data System (ADS)

    Guarini, E.; Neumann, M.; Bafile, U.; Celli, M.; Colognesi, D.; Bellissima, S.; Farhi, E.; Calzavara, Y.

    2016-06-01

    Very recently we showed that quantum centroid molecular dynamics (CMD) simulations of the velocity autocorrelation function provide, through the Gaussian approximation (GA), an appropriate representation of the single-molecule dynamic structure factor of liquid H2, as witnessed by a straightforward absolute-scale agreement between calculated and experimental values of the total neutron cross section (TCS) at thermal and epithermal incident energies. Also, a proper quantum evaluation of the self-dynamics was found to guarantee, via the simple Sköld model, a suitable account of the distinct (intermolecular) contributions that influence the neutron TCS of para-H2 for low-energy neutrons (below 10 meV). The very different role of coherent nuclear scattering in D2 makes the neutron response from this liquid much more extensively determined by the collective dynamics, even above the cold neutron range. Here we show that the Sköld approximation maintains its effectiveness in producing the correct cross section values also in the deuterium case. This confirms that the true key point for reliable computational estimates of the neutron TCS of the hydrogen liquids is, together with a good knowledge of the static structure factor, the modeling of the self part, which must take into due account quantum delocalization effects on the translational single-molecule dynamics. We demonstrate that both CMD and ring polymer molecular dynamics (RPMD) simulations provide similar results for the velocity autocorrelation function of liquid D2 and, consequently, for the neutron double differential cross section and its integrals. This second investigation completes and reinforces the validity of the proposed quantum method for the prediction of the scattering law of these cryogenic liquids, so important for cold neutron production and related condensed matter research.

  3. Construction and 1st Experiment of the 500-meter and 1000-meter DC Superconducting Power Cable in Ishikari

    NASA Astrophysics Data System (ADS)

    Yamaguchi, S.; Ivanov, Y.; Watanabe, H.; Chikumoto, N.; Koshiduka, H.; Hayashi, K.; Sawamura, T.

    Ishikari project constructs two lines. The length of the Line 1 is 500 m, and connects the photovoltaic cell to the internet-data center. The other line is 1 km length, and it is a test facility and called Line 2. The structures of the cable systems are not same to test their performance. The construction was started from 2014 in the field, the Line 1 was completed in May 2015, and it was cooled down and do the current experiment, and warmed up. The Line 2 is almost complete in October 2015. It will be tested in November and December, 2015. In order to reduce the stress of the cable induced by the thermal expansion and contraction, we adopted the way of the helical deformation of the cable. The force of the cable is reduced to 1/3 of an usual cable test. Because the cryogenic pipes are welded in the field and we cannot use the baking of the vacuum chamber of the cryogenic pipe, a new vacuum pumping method was proposed and tested for the cryogenic pipe. Since the straight pipes are used to compose the cryogenic pipe, the pressure drop of the circulation would be 1/100 of the corrugated pipe in the present condition, and it is suitable for longer cable system. The heat leak of the cryogenic pipe is ∼1.4W/m including the cable pipe's and the return pipe's. The heat leak of the current lead is ∼30W/kA in the test bench. Finally the current of 6kA/3 sec and the current of 5kA/15 min were achieved in Line 1. The reduction of heat leak will be a major subject of the longer cable system. The cost of the construction will be almost twice higher than that of the copper and aluminum over-head line with the iron tower in the present Japan. The cost construction of the over-head line is an average value, and depends on the newspaper.

  4. Volume 1, 1st Edition, Multiscale Tailoring of Highly Active and Stable Nanocomposite Catalysts, Final Technical Report

    SciTech Connect

    Veser, Goetz

    2009-08-31

    Nanomaterials have gained much attention as catalysts since the discovery of exceptional CO oxidation activity of nanoscale gold by Haruta. However, many studies avoid testing nanomaterials at the high-temperatures relevant to reactions of interest for the production of clean energy (T > 700°C). The generally poor thermal stability of catalytically active noble metals has thus far prevented significant progress in this area. We have recently overcome the poor thermal stability of nanoparticles by synthesizing a platinum barium-hexaaluminate (Pt-BHA) nanocomposite which combines the high activity of noble metal nanoparticles with the thermal stability of hexaaluminates. This Pt-BHA nanocomposite demonstrates excellent activity, selectivity, and long-term stability in CPOM. Pt-BHA is anchored onto a variety of support structures in order to improve the accessibility, safety, and reactivity of the nanocatalyst. Silica felts prove to be particularly amenable to this supporting procedure, with the resulting supported nanocatalyst proving to be as active and stable for CPOM as its unsupported counterpart. Various pre-treatment conditions are evaluated to determine their effectiveness in removing residual surfactant from the active nanoscale platinum particles. The size of these particles is measured across a wide temperature range, and the resulting “plateau” of stability from 600-900°C can be linked to a particle caging effect due to the structure of the supporting ceramic framework. The nanocomposites are used to catalyze the combustion of a dilute methane stream, and the results indicate enhanced activity for both Pt-BHA as well as ceria-doped BHA, as well as an absence of internal mass transfer limitations at the conditions tested. In water-gas shift reaction, nanocomposite Pt-BHA shows stability during prolonged WGS reaction and no signs of deactivation during start-up/shut-down of the reactor. The chemical and thermal stability, low molecular weight, and

  5. The November 1st, 1755 Tsunami in Morocco: Can Numerical Modeling Clarify the Uncertainties of Historical Reports?

    NASA Astrophysics Data System (ADS)

    Omira, R.; Baptista, M.; Mellas, S.; Leone, F.

    2010-12-01

    Coastal communities in the Atlantic marine limit of Morocco risk of inundation by regional and local tsunamis generated in the SW Iberia zone. Tsunami catalogs indicate that this area was the place of several tsunami events since historical time. Among them, the 1755 tsunami remains the largest eye witnessed historical event in the North East Atlantic area. Historical documents described, in some details, the generated waves along the coasts of Portugal, Spain and Morocco. They mentioned that the tsunami run-up has reached 15 m and the wave amplitude was as height as 26 m in some locations. However, these values of wave heights, run-up and inundated areas may were overestimated as it was revealed in the recent published critical studies of historical documents focused on the Gulf of Cadiz area. One of the coastal segments where the reported historical data, related to the 1755 event, are uncertain is the city of Mazagão, actually El-Jadida, located at the SW of Moroccan Atlantic coast. The present study seeks to numerically evaluate the tsunami impact along the El-Jadida coastal segment in order to clarify the uncertainties of the historical reports. A detailed numerical modeling of the tsunami waves evolution onshore and offshore El- Jadida site has been conducted. The digital terrain model (DTM) considered in this study is a reconstruction of the paleo-DTM of El-Jadida site in the 1750s, that we have computed from the paleo-bathymetric/topographic carts available before 1755. Earthquake scenarios of magnitude ~8.5 have been considered to represent a 1755-like event. Results in term of wave heights, maximum run-ups, high resolution inundation maps and flow limits for the study area have been presented for each candidate scenarios. Reliability of historical reports has been discussed in light of the comparison of these reports with the worst tsunami impact in El-Jadida obtained from numerical modeling. Keywords: 1755 tsunami; Morocco; tsunami modeling; historical

  6. 76 FR 78695 - Barry M. Schultz, M.D.; Decision and Order

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-19

    ... order for the emergency suspension of the Respondent's medical license (``ESO''), issued by the State of... outcome of his appeal of the ESO before the 1st District Tribunal of Appeals, State of Florida. . In the... inappropriate because the state's ESO, ``which forms the basis of the Government's integrity behind...

  7. Zero crossings properties of a narrow band process to determine the reliability of a two frequency encoding: Application to evaluating its autocorrelation envelope

    NASA Astrophysics Data System (ADS)

    Hay, J.

    1981-03-01

    A mathematical model of narrow band Gaussian noise zero crossing was developed to facilitate the calibration of electronic equipment for detecting two frequency codes on single track tape. The model makes use of the small probability that a narrow band process will have a long series of zero crossings. The model is also considered with respect to evaluating the autocorrelation envelope.

  8. Spatio-temporal autocorrelation of Neogene-Quaternary volcanic and clastic sedimentary rocks in SW Montana and SE Idaho: Relationship to Cenozoic tectonic and thermally induced extensional events

    NASA Astrophysics Data System (ADS)

    Davarpanah, A.; Babaie, H. A.; Dai, D.

    2013-12-01

    Two systems of full and half grabens have been forming since the mid-Tertiary through tectonic and thermally induced extensional events in SW Montana and neighboring SE Idaho. The earlier mid-Tertiary Basin and Range (BR) tectonic event formed the NW- and NE-striking mountains around the Snake River Plain (SRP) in Idaho and SW Montana, respectively. Since the mid-Tertiary, partially synchronous with the BR event, diachronous bulging and subsidence due to the thermally induced stress field of the Yellowstone hotspot (YHS) has produced the second system of variably-oriented grabens through faulting across the older BR fault blocks. The track of the migration of the YHS is defined by the presence of six prominent volcanic calderas along the SRP which become younger toward the present location of the YHS. Graben basins bounded by both the BR faults and thermally induced cross-faults (CF) systems are now filled with Tertiary-Quaternary clastic sedimentary and volcanic-volcaniclastic rocks. Neogene mafic and felsic lava which erupted along the SRP and clastic sedimentary units (Sixmile Creek Fm., Ts) deposited in both types of graben basins were classified based on their lithology and age, and mapped in ArcGIS 10 as polygon using a combination of MBMG and USGS databases and geological maps at scales of 1:250.000, 1:100,000, and 1:48,000. The spatio-temporal distributions of the lava polygons were then analyzed applying the Global and Local Moran`s I methods to detect any possible spatial or temporal autocorrelation relative to the track of the YHS. The results reveal the spatial autocorrelation of the lithology and age of the Neogene lavas, and suggest a spatio-temporal sequence of eruption of extrusive rocks between Miocene and late Pleistocene along the SRP. The sequence of eruptions, which progressively becomes younger toward the Yellowstone National Park, may track the migration of the YSH. The sub-parallelism of the trend of the SRP with the long axis of the

  9. Order Up

    ERIC Educational Resources Information Center

    Gibeault, Michael

    2005-01-01

    Change orders. The words can turn the stomachs of administrators. Horror stories about change orders create fear and distrust among school officials, designers and builders. Can change orders be avoided? If car manufacturers can produce millions of intricately designed vehicles, why can't the same quality control be achieved on a construction…

  10. Prominent Higher-Order Contributions to Electronic Recombination

    SciTech Connect

    Beilmann, C.; Mokler, P. H.; Bernitt, S.; Keitel, C. H.; Ullrich, J.; Lopez-Urrutia, J. R. Crespo; Harman, Z.

    2011-09-30

    Intershell higher-order (HO) electronic recombination is reported for highly charged Ar, Fe, and Kr ions, where simultaneous excitation of one K-shell electron and one or two additional L-shell electrons occurs upon resonant capture of a free electron. For the mid-Z region, HO resonance strengths grow unexpectedly strong with decreasing atomic number Z ({proportional_to}Z{sup -4}), such that, for Ar ions the 2nd-order overwhelms the 1st-order resonant recombination considerably. The experimental findings are confirmed by multiconfiguration Dirac-Fock calculations including hitherto neglected excitation pathways.

  11. HAWC 1st year catalog

    NASA Astrophysics Data System (ADS)

    Riviére, Colas; HAWC Collaboration

    2017-01-01

    The High Altitude Water Cherenkov (HAWC) Observatory was inaugurated in March 2015. With its high duty cycle and wide field of view, it observes 2/3 of the TeV sky daily. After a single year of observation, the integral sensitivity already exceeds that of the previous generation of wide field instruments by a factor of five. We will present the results of the first all sky search with a year of data of the complete HAWC detector. Some known sources as well as new TeV point and extended sources will be highlighted.

  12. Seismic Noise Auto-Correlation Function Changes Correlate with the Crustal Deformation for off-Izu Seismic Swarms

    NASA Astrophysics Data System (ADS)

    Ueno, T.; Saito, T.; Shiomi, K.; Enescu, B.; Hirose, H.

    2010-12-01

    Seismic swarms accompanied by crustal deformation have repeatedly occurred in the off-Izu peninsula region, central part of Japan. In the case of the recent 2006 and 2009 earthquake swarms, the NIED Hi-net stations detected clear accompanying tilt changes, which were interpreted as magma intrusions into the shallower crust, based on a dyke model (e.g., Okada et al., 2000). Recently, seismic noise Auto-Correlation Function (ACF) studies have been carried out intensively to detect possible temporal changes of crustal properties in regions of large earthquakes or at volcanoes (e.g., Wegler and Sens-Schonfelder, 2007). In this study we obtained ACFs by processing continuous seismic waveform data recorded by the Hi-net ITOH station, located closely to the Izu swarm area, and correlated the temporal changes of ACFs with the tilt records at the same station. We also investigated the possibility of continuous monitoring using ACFs and tilt records. We divided the continuous waveform data of 100 Hz sampling into segments of 5 minutes length, removed the mean and trend, and applied band-pass filtering and one-bit normalization, followed by auto-correlation. After that, we stacked the ACFs for a day to obtain stable ACF records. The temporal changes of ACFs versus time are analyzed by considering a reference ACF, which is the mean of ACFs for the time period without major seismic swarms. The tilt records were corrected for the tidal elements using the BAYTAP-G software (Tamura et al., 1991). After this processing, we determined the coherency between the temporal changes of ACF and tilt records. Usually the ACFs and the tilt records had separate, uncorrelated changes. The variety of changes suggests that the ACFs amplitudes and the tilt records were sensitive not only to crustal changes caused by seismic swarms or magma intrusion. However, just before the seismic swarm in December 2009, the coherency between the temporal changes of ACFs and tilt records started to be higher

  13. Levels of Salivary Enzymes of Apolygus Lucorum (Hemiptera: Miridae), From 1st Instar Nymph to Adult, and Their Potential Relation to Bug Feeding

    PubMed Central

    Tan, Xiumei; Xu, Xiuping; Gao, Yong; Yang, Qinmin; Zhu, Yunsheng; Wang, Jiqing; Wan, Fanghao; Zhou, Hongxu

    2016-01-01

    In recent years, Apolygus lucorum has caused increasing damage to cotton and fruit trees in China. The salivary enzymes secreted by A. lucorum when sucking on host plants induce a series of biochemical reactions in plants, and the pre-oral digestion benefits the bug feeding. In this study, the food intake of A. lucorum from 1st instar nymphs to adults was measured, and the corresponding salivary activity of pectinase, amylase, cellulase, protease, polyphenol oxidase and peroxidase was determined. Daily food intake varied with developmental stage, peaking in 3rd and 4th instar nymphs. Pectinase, amylase, cellulase and protease were detected in both nymphal and adult saliva of A. lucorum, while neither polyphenol oxidase nor peroxidase was detected. Protease activity varied with food intake peaking at the 3rd-4th instar, and then slightly decreasing at the 5th instar. Levels of pectinase, amylase and cellulase increased significantly with the daily feeding level until the 3rd instar, corresponding with increasing damage to host plants. The activity of both cellulase and protease had a significant linear relationship with the average daily food intake. The increasing activity of enzymes in saliva explain stage-specific impacts of A. lucorum on the host plants, and suggest that optimal management of A. lucorum would be confined to its control threshold prior to the peak of daily feeding in the 3rd instar. PMID:28002486

  14. The August 1st, 2014 ( M w 5.3) Moderate Earthquake: Evidence for an Active Thrust Fault in the Bay of Algiers (Algeria)

    NASA Astrophysics Data System (ADS)

    Benfedda, A.; Abbes, K.; Bouziane, D.; Bouhadad, Y.; Slimani, A.; Larbes, S.; Haddouche, D.; Bezzeghoud, M.

    2017-03-01

    On August 1st, 2014, a moderate-sized earthquake struck the capital city of Algiers at 05:11:17.6 (GMT+1). The earthquake caused the death of six peoples and injured 420, mainly following a panic movement among the population. Following the main shock, we surveyed the aftershock activity using a portable seismological network (short period), installed from August 2nd, 2014 to August 21st, 2015. In this work, first, we determined the main shock epicenter using the accelerograms recorded by the Algerian accelerograph network (under the coordination of the National Center of Applied Research in Earthquake Engineering-CGS). We calculated the focal mechanism of the main shock, using the inversion of the accelerograph waveforms in displacement that provides a reverse fault with a slight right-lateral component of slip and a compression axis striking NNW-SSE. The obtained scalar seismic moment ( M o = 1.25 × 1017 Nm) corresponds to a moment magnitude of M w = 5.3. Second, the analysis of the obtained aftershock swarm, of the survey, suggests an offshore ENE-WSW, trending and NNW dipping, causative active fault in the bay of Algiers, which may likely correspond to an offshore unknown segment of the Sahel active fault.

  15. Ethylene responsive element binding protein 1 (StEREBP1) from Solanum tuberosum increases tolerance to abiotic stress in transgenic potato plants.

    PubMed

    Lee, Hye Eun; Shin, Dongjin; Park, Sang Ryeol; Han, Sang-Eun; Jeong, Mi-Jeong; Kwon, Tack-Ryun; Lee, Seong-Kon; Park, Soo-Chul; Yi, Bu Young; Kwon, Hawk-Bin; Byun, Myung-Ok

    2007-02-23

    To identify components of the plant stress signal transduction cascade and response mechanisms, we screened plant genes using reverse Northern blot analysis, and chose the ethylene responsive element binding protein 1 (StEREBP1) for further characterization. To investigate its biological function in the potato, we performed Northern blot analysis and observed enhanced levels of transcription in response to several environmental stresses including low temperature. In vivo targeting experiments using a green fluorescent protein (GFP) reporter indicated that StEREBP1 localized to the nucleus of onion epidermal cells. StEREBP1 was found to bind to GCC and DRE/CRT cis-elements and both microarray and RT-PCR analyses indicated that overexpression of StEREBP1 induced expression of several GCC box-containing stress response genes. In addition, overexpression of StEREBP1 enhanced tolerance to cold and salt stress in transgenic potato plants. The results of this study suggest that StEREBP1 is a functional transcription factor that may be involved in abiotic stress responses in plants.

  16. Excerpts from the 1st international NTNU symposium on current and future clinical biomarkers of cancer: innovation and implementation, June 16th and 17th 2016, Trondheim, Norway.

    PubMed

    Robles, Ana I; Olsen, Karina Standahl; Tsui, Dana W T; Georgoulias, Vassilis; Creaney, Jenette; Dobra, Katalin; Vyberg, Mogens; Minato, Nagahiro; Anders, Robert A; Børresen-Dale, Anne-Lise; Zhou, Jianwei; Sætrom, Pål; Nielsen, Boye Schnack; Kirschner, Michaela B; Krokan, Hans E; Papadimitrakopoulou, Vassiliki; Tsamardinos, Ioannis; Røe, Oluf D

    2016-10-19

    The goal of biomarker research is to identify clinically valid markers. Despite decades of research there has been disappointingly few molecules or techniques that are in use today. The "1st International NTNU Symposium on Current and Future Clinical Biomarkers of Cancer: Innovation and Implementation", was held June 16th and 17th 2016, at the Knowledge Center of the St. Olavs Hospital in Trondheim, Norway, under the auspices of the Norwegian University of Science and Technology (NTNU) and the HUNT biobank and research center. The Symposium attracted approximately 100 attendees and invited speakers from 12 countries and 4 continents. In this Symposium original research and overviews on diagnostic, predictive and prognostic cancer biomarkers in serum, plasma, urine, pleural fluid and tumor, circulating tumor cells and bioinformatics as well as how to implement biomarkers in clinical trials were presented. Senior researchers and young investigators presented, reviewed and vividly discussed important new developments in the field of clinical biomarkers of cancer, with the goal of accelerating biomarker research and implementation. The excerpts of this symposium aim to give a cutting-edge overview and insight on some highly important aspects of clinical cancer biomarkers to-date to connect molecular innovation with clinical implementation to eventually improve patient care.

  17. Report from the 1st Cardiovascular Outcome Trial (CVOT) Summit of the Diabetes & Cardiovascular Disease (D&CVD) EASD Study Group.

    PubMed

    Schnell, Oliver; Standl, Eberhard; Catrinoiu, Doina; Genovese, Stefano; Lalic, Nebojsa; Skra, Jan; Valensi, Paul; Ceriello, Antonio

    2016-02-18

    The 1st Cardiovascular Outcome Trial (CVOT) Summit of the Diabetes & Cardiovascular Disease (D&CVD) EASD Study Group was held during the annual meeting on 30 October 2015 in Munich. This summit was organized in light of recently published and numerous ongoing CVOTs on diabetes, which have emerged in response to the FDA and the EMA Guidelines. The CVOT Summit stands as a novel conference setup, with the aim of serving as a reference meeting for all topics related to CVOTs in diabetes. Members of the steering committee of the D&CVD EASD Study Group constitute the backbone of the summit. It included presentations of key results on DPP-4 inhibitors, GLP-1-Analogues, SGLT-2 inhibitors, acarbose and insulins. Diabetologists' and cardiologists' perspective on the potential need of new study designs were also highlighted. Furthermore, panel discussions on the design of CVOTs on diabetes were included in the program. The D&CVD EASD Study Group will continue its activity. In-depth discussions and presentations of new CVOTs like LEADER, will be resumed at the 2nd CVOT on diabetes of the D&CVD EASD Study Group, which will be held from 20-22 October 2016 in Munich ( http://www.dcvd.org).

  18. Molecular cloning, functional characterization and expression of potato (Solanum tuberosum) 1-deoxy-d-xylulose 5-phosphate synthase 1 (StDXS1) in response to Phytophthora infestans.

    PubMed

    Henriquez, Maria Antonia; Soliman, Atta; Li, Genyi; Hannoufa, Abdelali; Ayele, Belay T; Daayf, Fouad

    2016-02-01

    1-Deoxy-D-xylulose 5-phosphate synthase (DXS) catalyzes the initial step of the plastidial 2C-methyl-D-erythritol-4-phosphate (DOXP-MEP) pathway involved in isoprenoid biosynthesis. In this study, we cloned the complete cDNA of potato DXS gene that was designated StDXS1. StDXS1 cDNA encodes for 719 amino acid residues, with MW of 77.8 kDa, and is present in one copy in the potato genome. Phylogenetic analysis and protein sequence alignments assigned StDXS1 to a group with DXS homologues from closely related species and exhibited homodomain identity with known DXS proteins from other plant species. Late blight symptoms occurred in parallel with a reduction in StDXS1 transcript levels, which may be associated with the levels of isoprenoids that contribute to plant protection against pathogens. Subcellular localization indicated that StDXS1 targets the chloroplasts where isoprenoids are synthesized. Arabidopsis expressing StDXS1 showed a higher accumulation of carotenoids and chlorophyll as compared to wild type controls. Lower levels of ABA and GA were detected in the transgenic DXS lines as compared to control plants, which reflected on higher germination rates of the transgenic DXS lines. No changes were detected in JA or SA contents. Selected downstream genes in the DOXP-MEP pathway, especially GGPPS genes, were up-regulated in the transgenic lines.

  19. Stable isotopic evidence for diet at the Imperial Roman coastal site of Velia (1st and 2nd centuries AD) in Southern Italy.

    PubMed

    Craig, Oliver E; Biazzo, Marco; O'Connell, Tamsin C; Garnsey, Peter; Martinez-Labarga, Cristina; Lelli, Roberta; Salvadei, Loretana; Tartaglia, Gianna; Nava, Alessia; Renò, Lorena; Fiammenghi, Antonella; Rickards, Olga; Bondioli, Luca

    2009-08-01

    Here we report on a stable isotope palaeodietary study of a Imperial Roman population interred near the port of Velia in Southern Italy during the 1st and 2nd centuries AD. Carbon and nitrogen stable isotope analyses were performed on collagen extracted from 117 adult humans as well as a range of fauna to reconstruct individual dietary histories. For the majority of individuals, we found that stable isotope data were consistent with a diet high in cereals, with relatively modest contributions of meat and only minor contributions of marine fish. However, substantial isotopic variation was found within the population, indicating that diets were not uniform. We suggest that a number of individuals, mainly but not exclusively males, had greater access to marine resources, especially high trophic level fish. However, the observed dietary variation did not correlate with burial type, number of grave goods, nor age at death. Also, individuals buried at the necropolis at Velia ate much less fish overall compared with the contemporaneous population from the necropolis of Portus at Isola Sacra, located on the coast close to Rome. Marine and riverine transport and commerce dominated the economy of Portus, and its people were in a position to supplement their own stocks of fish with imported goods in transit to Rome, whereas at Velia marine exploitation existed side-by-side with land-based economic activities.

  20. A hierarchical model of daily stream temperature using air-water temperature synchronization, autocorrelation, and time lags

    PubMed Central

    Hocking, Daniel J.; O’Neil, Kyle; Whiteley, Andrew R.; Nislow, Keith H.; O’Donnell, Matthew J.

    2016-01-01

    Water temperature is a primary driver of stream ecosystems and commonly forms the basis of stream classifications. Robust models of stream temperature are critical as the climate changes, but estimating daily stream temperature poses several important challenges. We developed a statistical model that accounts for many challenges that can make stream temperature estimation difficult. Our model identifies the yearly period when air and water temperature are synchronized, accommodates hysteresis, incorporates time lags, deals with missing data and autocorrelation and can include external drivers. In a small stream network, the model performed well (RMSE = 0.59°C), identified a clear warming trend (0.63 °C decade−1) and a widening of the synchronized period (29 d decade−1). We also carefully evaluated how missing data influenced predictions. Missing data within a year had a small effect on performance (∼0.05% average drop in RMSE with 10% fewer days with data). Missing all data for a year decreased performance (∼0.6 °C jump in RMSE), but this decrease was moderated when data were available from other streams in the network. PMID:26966662

  1. Autocorrelation analysis for the unbiased determination of power-law exponents in single-quantum-dot blinking.

    PubMed

    Houel, Julien; Doan, Quang T; Cajgfinger, Thomas; Ledoux, Gilles; Amans, David; Aubret, Antoine; Dominjon, Agnès; Ferriol, Sylvain; Barbier, Rémi; Nasilowski, Michel; Lhuillier, Emmanuel; Dubertret, Benoît; Dujardin, Christophe; Kulzer, Florian

    2015-01-27

    We present an unbiased and robust analysis method for power-law blinking statistics in the photoluminescence of single nanoemitters, allowing us to extract both the bright- and dark-state power-law exponents from the emitters' intensity autocorrelation functions. As opposed to the widely used threshold method, our technique therefore does not require discriminating the emission levels of bright and dark states in the experimental intensity timetraces. We rely on the simultaneous recording of 450 emission timetraces of single CdSe/CdS core/shell quantum dots at a frame rate of 250 Hz with single photon sensitivity. Under these conditions, our approach can determine ON and OFF power-law exponents with a precision of 3% from a comparison to numerical simulations, even for shot-noise-dominated emission signals with an average intensity below 1 photon per frame and per quantum dot. These capabilities pave the way for the unbiased, threshold-free determination of blinking power-law exponents at the microsecond time scale.

  2. Autocorrelation Analysis Combined with a Wavelet Transform Method to Detect and Remove Cosmic Rays in a Single Raman Spectrum.

    PubMed

    Maury, Augusto; Revilla, Reynier I

    2015-08-01

    Cosmic rays (CRs) occasionally affect charge-coupled device (CCD) detectors, introducing large spikes with very narrow bandwidth in the spectrum. These CR features can distort the chemical information expressed by the spectra. Consequently, we propose here an algorithm to identify and remove significant spikes in a single Raman spectrum. An autocorrelation analysis is first carried out to accentuate the CRs feature as outliers. Subsequently, with an adequate selection of the threshold, a discrete wavelet transform filter is used to identify CR spikes. Identified data points are then replaced by interpolated values using the weighted-average interpolation technique. This approach only modifies the data in a close vicinity of the CRs. Additionally, robust wavelet transform parameters are proposed (a desirable property for automation) after optimizing them with the application of the method in a great number of spectra. However, this algorithm, as well as all the single-spectrum analysis procedures, is limited to the cases in which CRs have much narrower bandwidth than the Raman bands. This might not be the case when low-resolution Raman instruments are used.

  3. Depolarized light scattering from prolate anisotropic particles: The influence of the particle shape on the field autocorrelation function.

    PubMed

    Passow, Christopher; ten Hagen, Borge; Löwen, Hartmut; Wagner, Joachim

    2015-07-28

    We provide a theoretical analysis for the intermediate scattering function typically measured in depolarized dynamic light scattering experiments. We calculate the field autocorrelation function g1(VH)(Q,t) in dependence on the wave vector Q and the time t explicitly in a vertical-horizontal scattering geometry for differently shaped solids of revolution. The shape of prolate cylinders, spherocylinders, spindles, and double cones with variable aspect ratio is expanded in rotational invariants flm(r). By Fourier transform of these expansion coefficients, a formal multipole expansion of the scattering function is obtained, which is used to calculate the weighting coefficients appearing in the depolarized scattering function. In addition to translational and rotational diffusion, especially the translational-rotational coupling of shape-anisotropic objects is considered. From the short-time behavior of the intermediate scattering function, the first cumulants Γ(Q) are calculated. In a depolarized scattering experiment, they deviate from the simple proportionality to Q(2). The coefficients flm(Q) strongly depend on the geometry and aspect ratio of the particles. The time dependence, in addition, is governed by the translational and rotational diffusion tensors, which are calculated by means of bead models for differently shaped particles in dependence on their aspect ratio. Therefore, our analysis shows how details of the particle shape--beyond their aspect ratio--can be determined by a precise scattering experiment. This is of high relevance in understanding smart materials which involve suspensions of anisotropic colloidal particles.

  4. Time-resolved imaging of magnetic vortex dynamics using holography with extended reference autocorrelation by linear differential operator.

    PubMed

    Bukin, N; McKeever, C; Burgos-Parra, E; Keatley, P S; Hicken, R J; Ogrin, F Y; Beutier, G; Dupraz, M; Popescu, H; Jaouen, N; Yakhou-Harris, F; Cavill, S A; van der Laan, G

    2016-10-31

    The magnetisation dynamics of the vortex core and Landau pattern of magnetic thin-film elements has been studied using holography with extended reference autocorrelation by linear differential operator (HERALDO). Here we present the first time-resolved x-ray measurements using this technique and investigate the structure and dynamics of the domain walls after excitation with nanosecond pulsed magnetic fields. It is shown that the average magnetisation of the domain walls has a perpendicular component that can change dynamically depending on the parameters of the pulsed excitation. In particular, we demonstrate the formation of wave bullet-like excitations, which are generated in the domain walls and can propagate inside them during the cyclic motion of the vortex core. Based on numerical simulations we also show that, besides the core, there are four singularities formed at the corners of the pattern. The polarisation of these singularities has a direct relation to the vortex core, and can be switched dynamically by the wave bullets excited with a magnetic pulse of specific parameters. The subsequent dynamics of the Landau pattern is dependent on the particular configuration of the polarisations of the core and the singularities.

  5. Preliminary evidence for the influence of physiography and scale upon the autocorrelation function of remotely sensed data

    NASA Technical Reports Server (NTRS)

    Labovitz, M. L.; Toll, D. L.; Kennard, R. E.

    1980-01-01

    Previously established results demonstrate that LANDSAT data are autocorrelated and can be described by a univariate linear stochastic process known as auto-regressive-integrated-moving-average model of degree 1, 0, 1 or ARIMA (1, 0, 1). This model has two coefficients of interest for interpretation phi(1) and theta(1). In a comparison of LANDSAT thematic mapper simulator (TMS) data and LANDSAT MSS data several results were established: (1) The form of the relatedness as described by this model is not dependent upon system look angle or pixel size. (2) The phi(1) coefficient increases with decreasing pixel size and increasing topographic complexity. (3) Changes in topography have a greater influence upon phi(1) than changes in land cover class. (4) The theta(1) seems to vary with the amount of atmospheric haze. These patterns of variation in phi(1) and theta(1) are potentially exploitable by the remote sensing community to yield stochastically independent sets of observations, characterize topography, and reduce the number of bytes needed to store remotely sensed data.

  6. Evolution of phenotype-environment associations by genetic responses to selection and phenotypic plasticity in a temporally autocorrelated environment.

    PubMed

    Michel, Matt J; Chevin, Luis-Miguel; Knouft, Jason H

    2014-05-01

    Covariation between population-mean phenotypes and environmental variables, sometimes termed a "phenotype-environment association" (PEA), can result from phenotypic plasticity, genetic responses to natural selection, or both. PEAs can potentially provide information on the evolutionary dynamics of a particular set of populations, but this requires a full theoretical characterization of PEAs and their evolution. Here, we derive formulas for the expected PEA in a temporally fluctuating environment for a quantitative trait with a linear reaction norm. We compare several biologically relevant scenarios, including constant versus evolving plasticity, and the situation in which an environment affects both development and selection but at different time periods. We find that PEAs are determined not only by biological factors (e.g., magnitude of plasticity, genetic variation), but also environmental factors, such as the association between the environments of development and of selection, and in some cases the level of temporal autocorrelation. We also describe how a PEA can be used to estimate the relationship between an optimum phenotype and an environmental variable (i.e., the environmental sensitivity of selection), an important parameter for determining the extinction risk of populations experiencing environmental change. We illustrate this ability using published data on the predator-induced morphological responses of tadpoles to predation risk.

  7. A hierarchical model of daily stream temperature using air-water temperature synchronization, autocorrelation, and time lags.

    PubMed

    Letcher, Benjamin H; Hocking, Daniel J; O'Neil, Kyle; Whiteley, Andrew R; Nislow, Keith H; O'Donnell, Matthew J

    2016-01-01

    Water temperature is a primary driver of stream ecosystems and commonly forms the basis of stream classifications. Robust models of stream temperature are critical as the climate changes, but estimating daily stream temperature poses several important challenges. We developed a statistical model that accounts for many challenges that can make stream temperature estimation difficult. Our model identifies the yearly period when air and water temperature are synchronized, accommodates hysteresis, incorporates time lags, deals with missing data and autocorrelation and can include external drivers. In a small stream network, the model performed well (RMSE = 0.59°C), identified a clear warming trend (0.63 °C decade(-1)) and a widening of the synchronized period (29 d decade(-1)). We also carefully evaluated how missing data influenced predictions. Missing data within a year had a small effect on performance (∼0.05% average drop in RMSE with 10% fewer days with data). Missing all data for a year decreased performance (∼0.6 °C jump in RMSE), but this decrease was moderated when data were available from other streams in the network.

  8. Time-resolved imaging of magnetic vortex dynamics using holography with extended reference autocorrelation by linear differential operator

    PubMed Central

    Bukin, N.; McKeever, C.; Burgos-Parra, E.; Keatley, P. S.; Hicken, R. J.; Ogrin, F. Y.; Beutier, G.; Dupraz, M.; Popescu, H.; Jaouen, N.; Yakhou-Harris, F.; Cavill, S. A.; van der Laan, G.

    2016-01-01

    The magnetisation dynamics of the vortex core and Landau pattern of magnetic thin-film elements has been studied using holography with extended reference autocorrelation by linear differential operator (HERALDO). Here we present the first time-resolved x-ray measurements using this technique and investigate the structure and dynamics of the domain walls after excitation with nanosecond pulsed magnetic fields. It is shown that the average magnetisation of the domain walls has a perpendicular component that can change dynamically depending on the parameters of the pulsed excitation. In particular, we demonstrate the formation of wave bullet-like excitations, which are generated in the domain walls and can propagate inside them during the cyclic motion of the vortex core. Based on numerical simulations we also show that, besides the core, there are four singularities formed at the corners of the pattern. The polarisation of these singularities has a direct relation to the vortex core, and can be switched dynamically by the wave bullets excited with a magnetic pulse of specific parameters. The subsequent dynamics of the Landau pattern is dependent on the particular configuration of the polarisations of the core and the singularities. PMID:27796347

  9. A hierarchical model of daily stream temperature using air-water temperature synchronization, autocorrelation, and time lags

    USGS Publications Warehouse

    Letcher, Benjamin; Hocking, Daniel; O'Neil, Kyle; Whiteley, Andrew R.; Nislow, Keith H.; O'Donnell, Matthew

    2016-01-01

    Water temperature is a primary driver of stream ecosystems and commonly forms the basis of stream classifications. Robust models of stream temperature are critical as the climate changes, but estimating daily stream temperature poses several important challenges. We developed a statistical model that accounts for many challenges that can make stream temperature estimation difficult. Our model identifies the yearly period when air and water temperature are synchronized, accommodates hysteresis, incorporates time lags, deals with missing data and autocorrelation and can include external drivers. In a small stream network, the model performed well (RMSE = 0.59°C), identified a clear warming trend (0.63 °C decade−1) and a widening of the synchronized period (29 d decade−1). We also carefully evaluated how missing data influenced predictions. Missing data within a year had a small effect on performance (∼0.05% average drop in RMSE with 10% fewer days with data). Missing all data for a year decreased performance (∼0.6 °C jump in RMSE), but this decrease was moderated when data were available from other streams in the network.

  10. Pseudo Order Kinetics Model to Predict the Adsorption Interaction of Corn-Stalk Adsorbent Surface with Metal Ion Adsorbate Cu (II) and Fe (II)

    NASA Astrophysics Data System (ADS)

    Haryanto, B.; Singh, W. B.; Barus, E. S.; Ridho, A.; Rawa, M. R.

    2017-01-01

    The adsorption process using cornstalk as adsorbent was used to remove the single metal ion such as copper ion and cadmium ion. The adsorption kinetics of each contaminant then used to predict the interaction type of metal ion on surface of corn stalk by calculating pseudo order 1st and 2nd. The identification type as chemically or physically interaction was predicted from the quality of r2 by plotting the adsorption capacity (q) and time (t). The r2 were 0.01 and 0.99 for pseudo order 1st and 2nd respectively for Fe (II). The r2 were 0.26 and 0.999 for pseudo order 1st and 2nd respectively for Cu (II). The result of adsorption interaction of metal ion and surface function of corn stalk is chemical type. SEM/EDX confirmed the Cu2+ presence on cornstalk surface.

  11. The 1st and the 2nd Italian Consensus Conferences on low-density lipoprotein-apheresis. A practical synopsis and update

    PubMed Central

    Stefanutti, Claudia

    2017-01-01

    The clinical indications and guidelines for low-density lipoprotein (LDL)-apheresis set by the 1st Italian Consensus Conference held in Ostuni in 1990 and completed in 1992, but never published, are reported schematically. In 1994, within the Project “Prevention and control of the factors of the disease (FATMA)” by the Italian National Research Council, subproject 8 “Control of cardiovascular disease”, a “Hearing on therapeutic apheresis: need for a target-oriented project” was organised. The meeting was the last scientific initiative on LDL-apheresis supported by public funds in Italy. After roughly two decades of use of LDL-apheresis, new guidelines were required based on the latest scientific evidence. In 2006, the Italian multicentre study on LDL-apheresis Working Group (IMSLDLa-WP), a scientific initiative at national level, was developed. It initially gathered together 19 Italian centres qualified for the application of lipid apheresis and LDL-apheresis (2007–2008), then 23 in 2010, located in the north, south, centre of Italy and in Sicily and Sardinia. The multicentre study aimed to validate the protocol for selecting patients and to create a network between the Italian centres. A secondary objective was the creation of a database of patients with familial hypercholesterolaemia and other severe forms of dyslipidaemia undergoing treatment with LDL-apheresis using the available techniques. Since LDL-apheresis has multidisciplinary treatment indications, the agreement on the new guidelines was reached through a panel of experts, of different medical and surgical specialties, with scientific and medical interest in the treatment indications, application and development of LDL-apheresis. The initiatives of the IMSLDLa-WP led to the 2nd Italian Consensus Conference on LDL-apheresis held in Rome in 2009. The previous and most recent guidelines are reported here synoptically. PMID:27416576

  12. Practice of use of antiemetic in patients for laparoscopic gynaecological surgery and its impact on the early (1st two hrs) postoperative period.

    PubMed

    Ismail, Samina

    2008-04-01

    There is no agreed technique for minimizing PONV (Postoperative Nausea and Vomiting) although some techniques are associated with low rate. Best practice involves identifying high risk patients and surgeries and use of prophylactic antiemetic where appropriate. Laparoscopic gynaecological surgery has high incidence of PONV (54-92%). An audit on the practice of antiemetic use in diagnostic laparoscopic gynaecological surgery was done in the department of anaesthesia of Aga Khan University Hospital from 1st January to 30th June 2006. We included all the patients scheduled for this procedure lasting less than 90 minutes. Anaesthetist involved in the audit identified the patient falling into the predetermined risk factors. The following facts about antiemetic were noted; whether the patients received any antiemetics or not, if it was prophylactic or rescue, type, dose route and timing of antiemetic. Patients were rated for any signs of nausea and vomiting (retching) after extubation in the operating room by the anaesthetist and in the recovery room or surgical day care unit (SDC) by the nurse who was briefed about it and was cross checked by the anaesthetist involved in the audit. This was done for two hours postoperatively. Our results showed that only 75% of patients with risk factors received an antiemetic. The most commonly used antiemetic was Metoclopramide. Eight percent of the patients had vomiting and all of them had received a prophylactic antiemetic. They received the same rescue antiemetic. This audit recommended institutional guidelines for the management of PONV. These should be based on evidence obtained from the published peer-reviewed studies. These guidelines could be communicated to health care workers involved in postoperative management of patients to help them achieve an optimal management strategy for this uncomfortable postoperative complication.

  13. PREFACE: 1st International Workshop on Theoretical and Computational Physics: Condensed Matter, Soft Matter and Materials Physics & 38th National Conference on Theoretical Physics

    NASA Astrophysics Data System (ADS)

    2014-09-01

    This volume contains selected papers presented at the 38th National Conference on Theoretical Physics (NCTP-38) and the 1st International Workshop on Theoretical and Computational Physics: Condensed Matter, Soft Matter and Materials Physics (IWTCP-1). Both the conference and the workshop were held from 29 July to 1 August 2013 in Pullman hotel, Da Nang, Vietnam. The IWTCP-1 was a new activity of the Vietnamese Theoretical Physics Society (VTPS) organized in association with the 38th National Conference on Theoretical Physics (NCTP-38), the most well-known annual scientific forum dedicated to the dissemination of the latest development in the field of theoretical physics within the country. The IWTCP-1 was also an External Activity of the Asia Pacific Center for Theoretical Physics (APCTP). The overriding goal of the IWTCP is to provide an international forum for scientists and engineers from academia to share ideas, problems and solution relating to the recent advances in theoretical physics as well as in computational physics. The main IWTCP motivation is to foster scientific exchanges between the Vietnamese theoretical and computational physics community and world-wide scientists as well as to promote high-standard level of research and education activities for young physicists in the country. About 110 participants coming from 10 countries participated in the conference and the workshop. 4 invited talks, 18 oral contributions and 46 posters were presented at the conference. In the workshop we had one keynote lecture and 9 invited talks presented by international experts in the fields of theoretical and computational physics, together with 14 oral and 33 poster contributions. The proceedings were edited by Nguyen Tri Lan, Trinh Xuan Hoang, and Nguyen Ai Viet. We would like to thank all invited speakers, participants and sponsors for making the conference and the workshop successful. Nguyen Ai Viet Chair of NCTP-38 and IWTCP-1

  14. Two-dimensional gratings of hexagonal holes for high order diffraction suppression.

    PubMed

    Liu, Ziwei; Shi, Lina; Pu, Tanchao; Li, Hailiang; Niu, Jiebin; Wang, Guanya; Xie, Changqing

    2017-01-23

    We propose two-dimensional gratings comprised of a large number of identical and similarly oriented hexagonal holes for the high order diffraction suppression. An analytical study of the diffraction property for such gratings, based on both square and triangle arrays, is described. The dependence of the high order diffraction property on the hole shape and size is investigated. Notably, theoretical calculation reveals that the 2nd, 3rd and 4th order diffractions adjacent to the 1st order diffraction can be completely suppressed, and the 5th order diffraction efficiency is as low as 0.01%, which will be submerged in the background noise for most practical applications. The 1st order diffraction intensity efficiency 6.93% can be achieved as the hexagonal holes along y-axis connect with each other. For the case of b=Py/3, the 1st order diffraction intensity efficiency is 3.08%. The experimental results are also presented, confirming the theoretical predictions. Especially, our two-dimensional gratings have the ability to form free-standing structures which are highly desired for the x-ray region. Comparing with the grating of the square array, the grating of the triangle array is easy to be fabricated by silicon planar process due to the large spacing between any two adjacent holes. Our results should be of great interest in a wide spectrum unscrambling from the infrared to the x-ray region.

  15. Structure of the North Anatolian Fault Zone from the Auto-Correlation of Ambient Seismic Noise Recorded at a Dense Seismometer Array

    NASA Astrophysics Data System (ADS)

    Taylor, D. G.; Rost, S.; Houseman, G.

    2015-12-01

    In recent years the technique of cross-correlating the ambient seismic noise wavefield at two seismometers to reconstruct empirical Green's Functions for the determination of Earth structure has been a powerful tool to study the Earth's interior without earthquake or man-made sources. However, far less attention has been paid to using auto-correlations of seismic noise to reveal body wave reflections from interfaces in the subsurface. In principle, the Green's functions thus derived should be comparable to the Earth's impulse response to a co-located source and receiver. We use data from a dense seismic array (Dense Array for Northern Anatolia - DANA) deployed across the northern branch of the North Anatolian Fault Zone (NAFZ) in the region of the 1999 magnitude 7.6 Izmit earthquake in western Turkey. The NAFZ is a major strike-slip system that extends ~1200 km across northern Turkey and continues to pose a high level of seismic hazard, in particular to the mega-city of Istanbul. We construct reflection images for the entire crust and upper mantle over the ~35 km by 70 km footprint of the 70-station DANA array. Using auto-correlations of vertical and horizontal components of ground motion, both P- and S-wave velocity information can be retrieved from the wavefield to constrain crustal structure further to established methods. We show that clear P-wave reflections from the crust-mantle boundary (Moho) can be retrieved using the autocorrelation technique, indicating topography on the Moho on horizontal scales of less than 10 km. Offsets in crustal structure can be identified that seem to be correlated with the surface expression of the fault zone in the region. The combined analysis of auto-correlations using vertical and horizontal components will lead to further insight into the fault zone structure throughout the crust and upper mantle.

  16. Non-Markovian spin-resolved counting statistics and an anomalous relation between autocorrelations and cross correlations in a three-terminal quantum dot

    NASA Astrophysics Data System (ADS)

    Luo, JunYan; Yan, Yiying; Huang, Yixiao; Yu, Li; He, Xiao-Ling; Jiao, HuJun

    2017-01-01

    We investigate the noise correlations of spin and charge currents through an electron spin resonance (ESR)-pumped quantum dot, which is tunnel coupled to three electrodes maintained at an equivalent chemical potential. A recursive scheme is employed with inclusion of the spin degrees of freedom to account for the spin-resolved counting statistics in the presence of non-Markovian effects due to coupling with a dissipative heat bath. For symmetric spin-up and spin-down tunneling rates, an ESR-induced spin flip mechanism generates a pure spin current without an accompanying net charge current. The stochastic tunneling of spin carriers, however, produces universal shot noises of both charge and spin currents, revealing the effective charge and spin units of quasiparticles in transport. In the case of very asymmetric tunneling rates for opposite spins, an anomalous relationship between noise autocorrelations and cross correlations is revealed, where super-Poissonian autocorrelation is observed in spite of a negative cross correlation. Remarkably, with strong dissipation strength, non-Markovian memory effects give rise to a positive cross correlation of the charge current in the absence of a super-Poissonian autocorrelation. These unique noise features may offer essential methods for exploiting internal spin dynamics and various quasiparticle tunneling processes in mesoscopic transport.

  17. Density of states and dynamical crossover in a dense fluid revealed by exponential mode analysis of the velocity autocorrelation function.

    PubMed

    Bellissima, S; Neumann, M; Guarini, E; Bafile, U; Barocchi, F

    2017-01-01

    Extending a preceding study of the velocity autocorrelation function (VAF) in a simulated Lennard-Jones fluid [Phys. Rev. E 92, 042166 (2015)PLEEE81539-375510.1103/PhysRevE.92.042166] to cover higher-density and lower-temperature states, we show that the recently demonstrated multiexponential expansion method allows for a full account and understanding of the basic dynamical processes encompassed by a fundamental quantity as the VAF. In particular, besides obtaining evidence of a persisting long-time tail, we assign specific and unambiguous physical meanings to groups of exponential modes related to the longitudinal and transverse collective dynamics, respectively. We have made this possible by consistently introducing the interpretation of the VAF frequency spectrum as a global density of states in fluids, generalizing a solid-state concept, and by giving to specific spectral components, obtained through the VAF exponential expansion, the corresponding meaning of partial densities of states relative to specific dynamical processes. The clear identification of a high-frequency oscillation of the VAF with the near-top excitation frequency in the dispersion curve of acoustic waves is a neat example of the power of the method. As for the transverse mode contribution, its analysis turns out to be particularly important, because the multiexponential expansion reveals a transition marking the onset of propagating excitations when the density is increased beyond a threshold value. While this finding agrees with the recent literature debating the issue of dynamical crossover boundaries, such as the one identified with the Frenkel line, we can add detailed information on the modes involved in this specific process in the domains of both time and frequency. This will help obtain a still missing full account of transverse dynamics, in both its nonpropagating and propagating aspects which are linked through dynamical transitions depending on both the thermodynamic states and

  18. Density of states and dynamical crossover in a dense fluid revealed by exponential mode analysis of the velocity autocorrelation function

    NASA Astrophysics Data System (ADS)

    Bellissima, S.; Neumann, M.; Guarini, E.; Bafile, U.; Barocchi, F.

    2017-01-01

    Extending a preceding study of the velocity autocorrelation function (VAF) in a simulated Lennard-Jones fluid [Phys. Rev. E 92, 042166 (2015), 10.1103/PhysRevE.92.042166] to cover higher-density and lower-temperature states, we show that the recently demonstrated multiexponential expansion method allows for a full account and understanding of the basic dynamical processes encompassed by a fundamental quantity as the VAF. In particular, besides obtaining evidence of a persisting long-time tail, we assign specific and unambiguous physical meanings to groups of exponential modes related to the longitudinal and transverse collective dynamics, respectively. We have made this possible by consistently introducing the interpretation of the VAF frequency spectrum as a global density of states in fluids, generalizing a solid-state concept, and by giving to specific spectral components, obtained through the VAF exponential expansion, the corresponding meaning of partial densities of states relative to specific dynamical processes. The clear identification of a high-frequency oscillation of the VAF with the near-top excitation frequency in the dispersion curve of acoustic waves is a neat example of the power of the method. As for the transverse mode contribution, its analysis turns out to be particularly important, because the multiexponential expansion reveals a transition marking the onset of propagating excitations when the density is increased beyond a threshold value. While this finding agrees with the recent literature debating the issue of dynamical crossover boundaries, such as the one identified with the Frenkel line, we can add detailed information on the modes involved in this specific process in the domains of both time and frequency. This will help obtain a still missing full account of transverse dynamics, in both its nonpropagating and propagating aspects which are linked through dynamical transitions depending on both the thermodynamic states and the excitation

  19. A complete theoretical description of the first-order delta-sigma modulation for analog-to-NRZ binary conversion

    NASA Astrophysics Data System (ADS)

    Siahmakoun, A.; Reeves, E.; Costanzo-Caso, P.

    2015-03-01

    A novel photonic analog-to-digital converter (ADC) based on asynchronous delta-sigma modulation (ADSM) has been investigated. The architecture utilizes an optical leaky integrator, optoelectronic bistable quantizer, and positive corrective feedback for a non-interferometric optical implementation of ADSM. The principles of the proposed 1st -order ADSM are mathematically modeled and simulated.

  20. Orthogonal Higher Order Structure and Confirmatory Factor Analysis of the French Wechsler Adult Intelligence Scale (WAIS-III)

    ERIC Educational Resources Information Center

    Golay, Philippe; Lecerf, Thierry

    2011-01-01

    According to the most widely accepted Cattell-Horn-Carroll (CHC) model of intelligence measurement, each subtest score of the Wechsler Intelligence Scale for Adults (3rd ed.; WAIS-III) should reflect both 1st- and 2nd-order factors (i.e., 4 or 5 broad abilities and 1 general factor). To disentangle the contribution of each factor, we applied a…

  1. Association between Birth Order and Emergency Room Visits and Acute Hospital Admissions following Pediatric Vaccination: A Self-Controlled Study

    PubMed Central

    Hawken, Steven; Kwong, Jeffrey C.; Deeks, Shelley L.; Crowcroft, Natasha S.; Ducharme, Robin; Manuel, Douglas G.; Wilson, Kumanan

    2013-01-01

    Objective We investigated the association between a child's birth order and emergency room (ER) visits and hospital admissions following 2-,4-,6- and 12-month pediatric vaccinations. Methods We included all children born in Ontario between April 1st, 2006 and March 31st, 2009 who received a qualifying vaccination. We identified vaccinations, ER visits and admissions using health administrative data housed at the Institute for Clinical Evaluative Sciences. We used the self-controlled case series design to compare the relative incidence (RI) of events among 1st-born and later-born children using relative incidence ratios (RIR). Results For the 2-month vaccination, the RIR for 1st-borns versus later-born children was 1.37 (95% CI: 1.19–1.57), which translates to 112 additional events/100,000 vaccinated. For the 4-month vaccination, the RIR for 1st-borns vs. later-borns was 1.70 (95% CI: 1.45–1.99), representing 157 additional events/100,000 vaccinated. At 6 months, the RIR for 1st vs. later-borns was 1.27 (95% CI: 1.09–1.48), or 77 excess events/100,000 vaccinated. At the 12-month vaccination, the RIR was 1.11 (95% CI: 1.02–1.21), or 249 excess events/100,000 vaccinated. Conclusions Birth order is associated with increased incidence of ER visits and hospitalizations following vaccination in infancy. 1st-born children had significantly higher relative incidence of events compared to later-born children. PMID:24324662

  2. The first-order giant neurons of the giant fiber system in the squid: electrophysiological and ultrastructural observations.

    PubMed

    Pozzo-Miller, L D; Moreira, J E; Llinás, R R

    1998-06-01

    The giant fiber system controlling mantle contraction used for jet propulsion in squid consists of two sets of three giant neurons organized in tandem. The somata of the 1st- and 2nd-order giant cells are located in the brain, while the perikarya of the 3rd-order giant cells are encountered in the stellate ganglia of the mantle. The somata and dendrites of one fused pair of 1st-order giant cells are thought to receive synaptic input from the eye, statocyst, skin proprioceptors, and supraesophageal lobes. To define the cellular properties for integration of such an extensive synaptic load, especially given its diversity, intracellular recordings and electron microscopic observations were performed on 1st-order giant cells in an isolated head preparation. Spontaneous bursts of action potentials and spikes evoked by extracellular stimulation of the brachial lobe were sensitive to the Na+ channel blocker TTX. Action potentials were also abolished by recording with microelectrodes containing the membrane impermeant, use dependent Na+ channel blocker QX-314. The small action potential amplitude and the abundant synaptic input imply that the spike initiation zone is remotely located from the recording site. The high spontaneous activity in the isolated head preparation, as well as the presence of synaptic junctions resembling inhibitory synapses, suggest; that afferent synapses on 1st-order giant neurons might represent the inhibitory control of the giant fiber system. The characterization of the electroresponsive properties of the 1st-order giant neurons will provide a description of the single cell integrative properties that trigger the rapid jet propulsion necessary for escape behavior in squid.

  3. Poincaré plot analysis of autocorrelation function of RR intervals in patients with acute myocardial infarction.

    PubMed

    Chuang, Shin-Shin; Wu, Kung-Tai; Lin, Chen-Yang; Lee, Steven; Chen, Gau-Yang; Kuo, Cheng-Deng

    2014-08-01

    The Poincaré plot of RR intervals (RRI) is obtained by plotting RRIn+1 against RRIn. The Pearson correlation coefficient (ρRRI), slope (SRRI), Y-intercept (YRRI), standard deviation of instantaneous beat-to-beat RRI variability (SD1RR), and standard deviation of continuous long-term RRI variability (SD2RR) can be defined to characterize the plot. Similarly, the Poincaré plot of autocorrelation function (ACF) of RRI can be obtained by plotting ACFk+1 against ACFk. The corresponding Pearson correlation coefficient (ρACF), slope (SACF), Y-intercept (YACF), SD1ACF, and SD2ACF can be defined similarly to characterize the plot. By comparing the indices of Poincaré plots of RRI and ACF between patients with acute myocardial infarction (AMI) and patients with patent coronary artery (PCA), we found that the ρACF and SACF were significantly larger, whereas the RMSSDACF/SDACF and SD1ACF/SD2ACF were significantly smaller in AMI patients. The ρACF and SACF correlated significantly and negatively with normalized high-frequency power (nHFP), and significantly and positively with normalized very low-frequency power (nVLFP) of heart rate variability in both groups of patients. On the contrary, the RMSSDACF/SDACF and SD1ACF/SD2ACF correlated significantly and positively with nHFP, and significantly and negatively with nVLFP and low-/high-frequency power ratio (LHR) in both groups of patients. We concluded that the ρACF, SACF, RMSSDACF/SDACF, and SD1ACF/SD2ACF, among many other indices of ACF Poincaré plot, can be used to differentiate between patients with AMI and patients with PCA, and that the increase in ρACF and SACF and the decrease in RMSSDACF/SDACF and SD1ACF/SD2ACF suggest an increased sympathetic and decreased vagal modulations in both groups of patients.

  4. [Marcov processes and neuronal engram formation--a model].

    PubMed

    Mager, P P

    1975-01-01

    The multivariate partial autocorrelation bases on the noncircular serial correlation matrices and is a problem of eigen values. Autoregressive oscillations of a time series and its order can be tested. MARCOV processes are 1st order processes, they are found during the conversion of short into long time memory (conditioned avoidance response).

  5. Spatial Autocorrelation Can Generate Stronger Correlations between Range Size and Climatic Niches Than the Biological Signal — A Demonstration Using Bird and Mammal Range Maps

    PubMed Central

    Boucher-Lalonde, Véronique; Currie, David J.

    2016-01-01

    Species’ geographic ranges could primarily be physiological tolerances drawn in space. Alternatively, geographic ranges could be only broadly constrained by physiological climatic tolerances: there could generally be much more proximate constraints on species’ ranges (dispersal limitation, biotic interactions, etc.) such that species often occupy a small and unpredictable subset of tolerable climates. In the literature, species’ climatic tolerances are typically estimated from the set of conditions observed within their geographic range. Using this method, studies have concluded that broader climatic niches permit larger ranges. Similarly, other studies have investigated the biological causes of incomplete range filling. But, when climatic constraints are measured directly from species’ ranges, are correlations between species’ range size and climate necessarily consistent with a causal link? We evaluated the extent to which variation in range size among 3277 bird and 1659 mammal species occurring in the Americas is statistically related to characteristics of species’ realized climatic niches. We then compared how these relationships differed from the ones expected in the absence of a causal link. We used a null model that randomizes the predictor variables (climate), while retaining their broad spatial autocorrelation structure, thereby removing any causal relationship between range size and climate. We found that, although range size is strongly positively related to climatic niche breadth, range filling and, to a lesser extent, niche position in nature, the observed relationships are not always stronger than expected from spatial autocorrelation alone. Thus, we conclude that equally strong relationships between range size and climate would result from any processes causing ranges to be highly spatially autocorrelated. PMID:27855201

  6. Spatial and Temporal Characterization of Femtosecond Pulses at High-Numerical Aperture Using Collinear, Background-Free, Third-Harmonic Autocorrelation

    SciTech Connect

    Fittinghoff, D N; der Au, J A; Squier, J A

    2004-08-09

    We show that a simple plane wave analysis can be used even under tight focusing conditions to predict the dependence of third-harmonic generation on the polarization state of the incident beam. Exploiting this fact, we then show that circularly polarized beams may be used to spatially characterize the beam focus and temporally characterize ultrashort pulses in high numerical aperture systems by experimentally demonstrating, for the first time, novel collinear, background-free, third-harmonic intensity autocorrelations in time and space in a high numerical aperture microscope. We also discuss the possibility of using third harmonic generation with circularly polarized beams for background-free collinear frequency resolved optical gating.

  7. The adaptive nature of liquidity taking in limit order books

    NASA Astrophysics Data System (ADS)

    Taranto, D. E.; Bormetti, G.; Lillo, F.

    2014-06-01

    In financial markets, the order flow, defined as the process assuming value one for buy market orders and minus one for sell market orders, displays a very slowly decaying autocorrelation function. Since orders impact prices, reconciling the persistence of the order flow with market efficiency is a subtle issue. A possible solution is provided by asymmetric liquidity, which states that the impact of a buy or sell order is inversely related to the probability of its occurrence. We empirically find that when the order flow predictability increases in one direction, the liquidity in the opposite side decreases, but the probability that a trade moves the price decreases significantly. While the last mechanism is able to counterbalance the persistence of order flow and restore efficiency and diffusivity, the first acts in the opposite direction. We introduce a statistical order book model where the persistence of the order flow is mitigated by adjusting the market order volume to the predictability of the order flow. The model reproduces the diffusive behaviour of prices at all time scales without fine-tuning the values of parameters, as well as the behaviour of most order book quantities as a function of the local predictability of the order flow.

  8. FOREWORD: 13th International Workshop on Plasma-Facing Materials and Components for Fusion Applications/1st International Conference on Fusion Energy Materials Science 13th International Workshop on Plasma-Facing Materials and Components for Fusion Applications/1st International Conference on Fusion Energy Materials Science

    NASA Astrophysics Data System (ADS)

    Jacob, Wolfgang; Linsmeier, Christian; Rubel, Marek

    2011-12-01

    The 13th International Workshop on Plasma-Facing Materials and Components (PFMC-13) jointly organized with the 1st International Conference on Fusion Energy Materials Science (FEMaS-1) was held in Rosenheim (Germany) on 9-13 May 2011. PFMC-13 is a successor of the International Workshop on Carbon Materials for Fusion Applications series. Between 1985 and 2003 ten 'Carbon Workshops' were organized in Jülich, Stockholm and Hohenkammer. Then it was time for a change and redefinition of the scope of the symposium to reflect the new requirements of ITER and the ongoing evolution in the field. Under the new name (PFMC-11), the workshop was first organized in 2006 in Greifswald, Germany and PFMC-12 took place in Jülich in 2009. Initially starting in 1985 with about 40 participants as a 1.5 day workshop, the event has continuously grown to about 220 participants at PFMC-12. Due to the joint organization with FEMaS-1, PFMC-13 set a new record with more than 280 participants. The European project Fusion Energy Materials Science, FEMaS, coordinated by the Max-Planck-Institut für Plasmaphysik (IPP), organizes and stimulates cooperative research activities which involve large-scale research facilities as well as other top-level materials characterization laboratories. Five different fields are addressed: benchmarking experiments for radiation damage modelling, the application of micro-mechanical characterization methods, synchrotron and neutron radiation-based techniques and advanced nanoscopic analysis based on transmission electron microscopy. All these fields need to be exploited further by the fusion materials community for timely materials solutions for a DEMO reactor. In order to integrate these materials research fields, FEMaS acted as a co-organizer for the 2011 workshop and successfully introduced a number of participants from research labs and universities into the PFMC community. Plasma-facing materials experience particularly hostile conditions as they are

  9. Autocorrelation standard deviation and root mean square frequency analysis of polymer electrolyte membrane fuel cell to monitor for hydrogen and air undersupply

    NASA Astrophysics Data System (ADS)

    Kim, Joo Gon; Mukherjee, Santanu; Bates, Alex; Zickel, Benjamin; Park, Sam; Son, Byung Rak; Choi, Jae Sung; Kwon, Osung; Lee, Dong Ha; Chung, Hyun-Youl

    2015-12-01

    Proton exchange membrane fuel cells are a promising energy conversion device which can help to solve urgent environmental and economic problems. Among the various types of fuel cells, the air breathing proton exchange membrane fuel cell, which minimizes the balance of plant, has drawn a lot of attention due to its superior energy density. In this study a compact, air breathing, proton exchange membrane fuel cell based on Nafion and a Pt/C membrane electrode assembly was designed. The fuel cell was tested using a Scribner Associates 850e fuel cell test station. Specifically, the hydrogen fuel and oxygen starvation of the fuel cell were accurately and systematically tested and analyzed using a frequency analysis method which can analyze the input and output frequency. The analysis of the frequency variation under a fuel starvation condition was done using RMSF (root mean square frequency) and ACSD (autocorrelation standard deviation). The study reveals two significant results: first, the fuel starvations show entirely different phenomenon in both RMSF and ACSD and second, the results of the Autocorrelation show clearer results for fuel starvation detection than the results with RMSF.

  10. Trajectory variance and autocorrelations within single-sperm tracks as population-level descriptors of sperm track complexity, predictability, and energy-generating ability.

    PubMed

    Abaigar, Teresa; Barbero, Javier; Holt, William V

    2012-01-01

    The objectives of the present study were to develop an alternative theoretical approach to the analysis of sperm motility and to develop motility parameters that would complement those more commonly used in current computer-assisted semen analysis procedures. We have defined a set of parameters and have tested them using boar spermatozoa undergoing bicarbonate-induced motility activation. The new parameters were calculated for a series of (x,y) coordinates of sperm head positions recorded at each move along the trajectory. The parameters were: mean velocity (MV), immobility ratio, fractal dimension (FD), the variance of the steplengths (VAR), and 2 autocorrelation function coefficients of the step-length time series for lags 1 and 2 (C(1) and C(2)). MV measures the average speed along the trajectory, and VAR is a measure of displacement variability that can be related to the specific mean (per step) kinetic energy of the spermatozoon. All of the parameters except MV and FD were affected by the sampling frequency (25 vs 50 Hz); inappropriately high sampling frequency in relation to magnification resulted in step-lengths between successive frames that were below the resolution threshold of the imaging system. The autocorrelation functions were especially informative; discrimination between sperm subpopulations was obvious within simple histogram formats, and complex statistical analyses were not needed for their identification.

  11. Seismic body-wave interferometry using noise autocorrelations for crustal structure and a tutorial on 3D seismic processing and imaging using Madagascar

    NASA Astrophysics Data System (ADS)

    Olejnik, Peter

    Seismic body-wave interferometry is applied to selected seismic stations from the USArray Earthscope Transportable Array (TA) by autocorrelating ambient seismic noise recordings to construct effective zero-offset reflection seismograms. The robustness of the auto-correlations of noise traces is first tested on a TA station in Nevada where body-wave reflections similar to those found in an earlier study are identified. This approach is then applied to several TA stations in the central U.S., and the results are compared with synthetic data. Different stacking time periods are then examined to find the shortest time intervals that provide stable correlation stacks. A tutorial on 3D seismic processing and imaging using the Madagascar open-source software package is next presented for educational purposes. The 3D Teapot Dome seismic data set is examined to illustrate the processing and imaging steps. A number of processing steps are applied to the data set, including amplitude gaining, muting, deconvolution, static corrections, velocity analysis, normal moveout (NMO) correction, and stacking. Post-stack time and depth migrations are then performed on the stacked data along with post-migration f-x deconvolution.

  12. The Hospital Microbiome Project: Meeting Report for the 1st Hospital Microbiome Project Workshop on sampling design and building science measurements, Chicago, USA, June 7th-8th 2012.

    PubMed

    Smith, Daniel; Alverdy, John; An, Gary; Coleman, Maureen; Garcia-Houchins, Sylvia; Green, Jessica; Keegan, Kevin; Kelley, Scott T; Kirkup, Benjamin C; Kociolek, Larry; Levin, Hal; Landon, Emily; Olsiewski, Paula; Knight, Rob; Siegel, Jeffrey; Weber, Stephen; Gilbert, Jack

    2013-04-15

    This report details the outcome of the 1st Hospital Microbiome Project workshop held on June 7th-8th, 2012 at the University of Chicago, USA. The workshop was arranged to determine the most appropriate sampling strategy and approach to building science measurement to characterize the development of a microbial community within a new hospital pavilion being built at the University of Chicago Medical Center. The workshop made several recommendations and led to the development of a full proposal to the Alfred P. Sloan Foundation as well as to the creation of the Hospital Microbiome Consortium.

  13. 78 FR 39255 - Antidumping or Countervailing Duty Order, Finding, or Suspended Investigation; Advance...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-01

    ...-570-912) (202) 482-5047 (1st Review). Raw Flexible Magnets from Jennifer Moats China (A-570-922) (1st (202) 482-5047 Review). Raw Flexible Magnets from David Goldberger Taiwan (A-583-842) (1st (202) 482... China (C-570-913) (202) 482-1391 (1st Review). Raw Flexible Magnets from Jennifer Moats China...

  14. Empirical Evidence of a Comprehensive Model of School Effectiveness: A Multilevel Study in Mathematics in the 1st Year of Junior General Education in The Netherlands

    ERIC Educational Resources Information Center

    de Jong, R.; Westerhof, K. J.; Kruiter, J. H.

    2004-01-01

    In the field of school effectiveness and school improvement, scholars as well as practitioners often complain about the absence of theory to guide their work. To fill this gap, Creemers (1994) developed a comprehensive model of educational effectiveness. In order to gain empirical evidence, we tested some of the main components of the model in…

  15. 1st, 2nd and 3rd Generation Implementations of an eLearning Design: Re-Use from Postgraduate Law to Block/Online Engineering Course

    ERIC Educational Resources Information Center

    Lambert, Sarah; Brewer, Chris

    2007-01-01

    In order to meet the demands of postgraduate students who were time poor and unable to regularly attend face-to-face classes, one lecturer in the Faculty Law at the University of Wollongong (UOW) sought the assistance of a Learning Designer to redesign the Postgraduate Practical Legal Training (PLT) program into a flexible blended learning format,…

  16. Orthogonal higher order structure and confirmatory factor analysis of the French Wechsler Adult Intelligence Scale (WAIS-III).

    PubMed

    Golay, Philippe; Lecerf, Thierry

    2011-03-01

    According to the most widely accepted Cattell-Horn-Carroll (CHC) model of intelligence measurement, each subtest score of the Wechsler Intelligence Scale for Adults (3rd ed.; WAIS-III) should reflect both 1st- and 2nd-order factors (i.e., 4 or 5 broad abilities and 1 general factor). To disentangle the contribution of each factor, we applied a Schmid-Leiman orthogonalization transformation (SLT) to the standardization data published in the French technical manual for the WAIS-III. Results showed that the general factor accounted for 63% of the common variance and that the specific contributions of the 1st-order factors were weak (4.7%-15.9%). We also addressed this issue by using confirmatory factor analysis. Results indicated that the bifactor model (with 1st-order group and general factors) better fit the data than did the traditional higher order structure. Models based on the CHC framework were also tested. Results indicated that a higher order CHC model showed a better fit than did the classical 4-factor model; however, the WAIS bifactor structure was the most adequate. We recommend that users do not discount the Full Scale IQ when interpreting the index scores of the WAIS-III because the general factor accounts for the bulk of the common variance in the French WAIS-III. The 4 index scores cannot be considered to reflect only broad ability because they include a strong contribution of the general factor.

  17. FY-2015 FES (Fusion and Energy Sciences) Joint Research Target: Final Report for the Period October 1st, 2014, through September 30th, 2015

    SciTech Connect

    Podesta, M.; Holcomb, C.; Wallace, G.; Gerhardt, S. P.; Scott, S. D.; Solomon, W.

    2015-09-30

    Annual JRT-15 Target: Conduct experiments and analysis to quantify the impact of broadened current and pressure profiles on tokamak plasma confinement and stability. Broadened pressure profiles generally improve global stability but can also affect transport and confinement, while broadened current profiles can have both beneficial and adverse impacts on confinement and stability. This research will examine a variety of heating and current drive techniques in order to validate theoretical models of both the actuator performance and the transport and global stability response to varied heating and current drive deposition.

  18. AIAA, ASME, SIAM, and APS, National Fluid Dynamics Congress, 1st, Cincinnati, OH, July 25-28, 1988, Technical Papers. Parts 1, 2, & 3

    NASA Astrophysics Data System (ADS)

    The present conference on fluid dynamics discusses the application of cellular automata to fluid dynamics problems, adaptive grid computation for inviscid compressible flows using a pressure-correction method, a stream-function formulation for the multiply-connected driven cavity Stokes flow problem, the simulation of a vortex ring, fast algorithms for vortex methods, pseudospectral solutions of separated flows, a third-order multidimensional Euler/Navier-Stokes solver, and a multigrid strategy for the investigation of highly recirculating flows. Also discussed are surface pressure fluctuations due to impinging vortical flows on an airfoil, the application of polymer drag reduction to sewer flow problems, fully developed pulsating turbulent flows, vortex-dominated slender-wing problems, a turbulence model for rotating flows, CFD on parallel processors, the order of panel methods, unsteady wing theory, radial jet reattachment flow, mode-switching in supersonic circular jets, unsteady dynamics in aeroacoustics, the gas dynamics of fission-fragment heating, Gortler vortices in supersonic boundary layers, boundary layer receptivity mechanisms, cavitation in a confined vortex, and dynamical states in thermal lensing.

  19. Application of higher order statistics/spectra in biomedical signals--a review.

    PubMed

    Chua, Kuang Chua; Chandran, Vinod; Acharya, U Rajendra; Lim, Choo Min

    2010-09-01

    For many decades correlation and power spectrum have been primary tools for digital signal processing applications in the biomedical area. The information contained in the power spectrum is essentially that of the autocorrelation sequence; which is sufficient for complete statistical descriptions of Gaussian signals of known means. However, there are practical situations where one needs to look beyond autocorrelation of a signal to extract information regarding deviation from Gaussianity and the presence of phase relations. Higher order spectra, also known as polyspectra, are spectral representations of higher order statistics, i.e. moments and cumulants of third order and beyond. HOS (higher order statistics or higher order spectra) can detect deviations from linearity, stationarity or Gaussianity in the signal. Most of the biomedical signals are non-linear, non-stationary and non-Gaussian in nature and therefore it can be more advantageous to analyze them with HOS compared to the use of second-order correlations and power spectra. In this paper we have discussed the application of HOS for different bio-signals. HOS methods of analysis are explained using a typical heart rate variability (HRV) signal and applications to other signals are reviewed.

  20. Radiosurgical treatment of uterine cervix carcinoma at the 1st Clinic of Obstetrics and Gynecology of the University of Turin, (in the period 1972-1978).

    PubMed

    Bocci, A; Sismondi, P; Sinistrero, G; Fessia, L; Zola, P; Giardina, G; Saluzzo, F; Mano, M P; Dalmassso, A

    1981-01-01

    The Authors report the results of a planned prospective study on Radiosurgical treatment of carcinoma of the cervix at stage Ia, Ib, and IIa. The protocol adopted is based on preoperative Curietherapy performed by Ir192 on a after loading technique device, hysterectomy according the Wertheim-Meigs' technique with systematic lymphadenectomy for the internal and external iliacs and obturator stations, Telecobalt therapy in cases with hystological evidence of lymphatic spread. The Authors discuss the results after three and five years in term of survival according to stage and type of treatment, the anatomosurgical examination and the histologic findings of the lymph nodes. At the end, they analysed the complications according to the stage and the kind of treatment, studying only recovered patients and performing the analysis after three years, in order to allow all complications to appear.

  1. Post waterflood CO2 miscible flood in light oil fluvial - dominated deltaic reservoirs. Technical progress report, October 1, 1994--December 30, 1994. 1st Quarter, fiscal year 1995

    SciTech Connect

    1994-01-15

    Production is averaging about 450 BOPD for the quarter. The fluctuation was primarily due to a temporary shutdown of CO{sub 2} delivery and maturing of the first WAG cycle. CO{sub 2} and water injection were reversed again in order to optimize changing yields and water cuts in the producing wells. Measured BHP was close to the anticipated value. A limited CO{sub 2} volume of 120 MMCF was injected to stimulate well Kuhn No. 6 to test the Huff-Puff process, since the well did not respond to CO{sub 2} injection from the main reservoir. The well will be placed on February 1, 1995. Total CO{sub 2} injection averaged this quarter about 8.8 MMCFD, including 3.6 MMCFD purchased CO{sub 2} from Cardox. The stratigraphy of the sand deposits is also discussed.

  2. High levels of virological failure with major genotypic resistance mutations in HIV-1-infected children after 5 years of care according to WHO-recommended 1st-line and 2nd-line antiretroviral regimens in the Central African Republic: A cross-sectional study.

    PubMed

    Mossoro-Kpinde, Christian Diamant; Gody, Jean-Chrysostome; Mboumba Bouassa, Ralph-Sydney; Mbitikon, Olivia; Jenabian, Mohammad-Ali; Robin, Leman; Matta, Mathieu; Zeitouni, Kamal; Longo, Jean De Dieu; Costiniuk, Cecilia; Grésenguet, Gérard; Touré Kane, Ndèye Coumba; Bélec, Laurent

    2017-03-01

    A large cohort of 220 HIV-1-infected children (median [range] age: 12 [4-17] years) was cared and followed up in the Central African Republic, including 198 in 1st-line and 22 in 2nd-line antiretroviral regimens. Patients were monitored clinically and biologically for HIV-1 RNA load and drug resistance mutations (DRMs) genotyping. A total of 87 (40%) study children were virological responders and 133 (60%) nonresponders. In children with detectable viral load, the majority (129; 97%) represented a virological failure. In children receiving 1st-line regimens in virological failure for whom genotypic resistance test was available, 45% displayed viruses harboring at least 1 DRM to NNRTI or NRTI, and 26% showed at least 1 major DRM to NNRTI or NRTI; more than half of children in 1st-line regimens were resistant to 1st-generation NNRTI and 24% of the children in 1st-line regimens had a major DRMs to PI. Virological failure and selection of DRMs were both associated with poor adherence. These observations demonstrate high rate of virological failure after 3 to 5 years of 1st-line or 2nd-line antiretroviral treatment, which is generally associated with DRMs and therapeutic failure. Overall, more than half (55%) of children receiving 1st-line antiretroviral treatment for a median of 3.4 years showed virological failure and antiretroviral-resistance and thus eligible to 2nd-line treatment. Furthermore, two-third (64%) of children under 2nd-line therapy were eligible to 3rd-line regimen. Taken together, these observations point the necessity to monitor antiretroviral-treated children by plasma HIV-1 RNA load to diagnose as early as possible the therapeutic failure and operate switch to a new therapeutic line.

  3. High levels of virological failure with major genotypic resistance mutations in HIV-1-infected children after 5 years of care according to WHO-recommended 1st-line and 2nd-line antiretroviral regimens in the Central African Republic

    PubMed Central

    Mossoro-Kpinde, Christian Diamant; Gody, Jean-Chrysostome; Mboumba Bouassa, Ralph-Sydney; Mbitikon, Olivia; Jenabian, Mohammad-Ali; Robin, Leman; Matta, Mathieu; Zeitouni, Kamal; Longo, Jean De Dieu; Costiniuk, Cecilia; Grésenguet, Gérard; Touré Kane, Ndèye Coumba; Bélec, Laurent

    2017-01-01

    Abstract A large cohort of 220 HIV-1-infected children (median [range] age: 12 [4–17] years) was cared and followed up in the Central African Republic, including 198 in 1st-line and 22 in 2nd-line antiretroviral regimens. Patients were monitored clinically and biologically for HIV-1 RNA load and drug resistance mutations (DRMs) genotyping. A total of 87 (40%) study children were virological responders and 133 (60%) nonresponders. In children with detectable viral load, the majority (129; 97%) represented a virological failure. In children receiving 1st-line regimens in virological failure for whom genotypic resistance test was available, 45% displayed viruses harboring at least 1 DRM to NNRTI or NRTI, and 26% showed at least 1 major DRM to NNRTI or NRTI; more than half of children in 1st-line regimens were resistant to 1st-generation NNRTI and 24% of the children in 1st-line regimens had a major DRMs to PI. Virological failure and selection of DRMs were both associated with poor adherence. These observations demonstrate high rate of virological failure after 3 to 5 years of 1st-line or 2nd-line antiretroviral treatment, which is generally associated with DRMs and therapeutic failure. Overall, more than half (55%) of children receiving 1st-line antiretroviral treatment for a median of 3.4 years showed virological failure and antiretroviral-resistance and thus eligible to 2nd-line treatment. Furthermore, two-third (64%) of children under 2nd-line therapy were eligible to 3rd-line regimen. Taken together, these observations point the necessity to monitor antiretroviral-treated children by plasma HIV-1 RNA load to diagnose as early as possible the therapeutic failure and operate switch to a new therapeutic line. PMID:28272247

  4. All Roads Lead to Rome: Exploring Human Migration to the Eternal City through Biochemistry of Skeletons from Two Imperial-Era Cemeteries (1st-3rd c AD).

    PubMed

    Killgrove, Kristina; Montgomery, Janet

    2016-01-01

    Migration within the Roman Empire occurred at multiple scales and was engaged in both voluntarily and involuntarily. Because of the lengthy tradition of classical studies, bioarchaeological analyses must be fully contextualized within the bounds of history, material culture, and epigraphy. In order to assess migration to Rome within an updated contextual framework, strontium isotope analysis was performed on 105 individuals from two cemeteries associated with Imperial Rome-Casal Bertone and Castellaccio Europarco-and oxygen and carbon isotope analyses were performed on a subset of 55 individuals. Statistical analysis and comparisons with expected local ranges found several outliers who likely immigrated to Rome from elsewhere. Demographics of the immigrants show men and children migrated, and a comparison of carbon isotopes from teeth and bone samples suggests the immigrants may have significantly changed their diet. These data represent the first physical evidence of individual migrants to Imperial Rome. This case study demonstrates the importance of employing bioarchaeology to generate a deeper understanding of a complex ancient urban center.

  5. All Roads Lead to Rome: Exploring Human Migration to the Eternal City through Biochemistry of Skeletons from Two Imperial-Era Cemeteries (1st-3rd c AD)

    PubMed Central

    Killgrove, Kristina; Montgomery, Janet

    2016-01-01

    Migration within the Roman Empire occurred at multiple scales and was engaged in both voluntarily and involuntarily. Because of the lengthy tradition of classical studies, bioarchaeological analyses must be fully contextualized within the bounds of history, material culture, and epigraphy. In order to assess migration to Rome within an updated contextual framework, strontium isotope analysis was performed on 105 individuals from two cemeteries associated with Imperial Rome—Casal Bertone and Castellaccio Europarco—and oxygen and carbon isotope analyses were performed on a subset of 55 individuals. Statistical analysis and comparisons with expected local ranges found several outliers who likely immigrated to Rome from elsewhere. Demographics of the immigrants show men and children migrated, and a comparison of carbon isotopes from teeth and bone samples suggests the immigrants may have significantly changed their diet. These data represent the first physical evidence of individual migrants to Imperial Rome. This case study demonstrates the importance of employing bioarchaeology to generate a deeper understanding of a complex ancient urban center. PMID:26863610

  6. Prevalence of ST1193 clone and IncI1/ST16 plasmid in E-coli isolates carrying blaCTX-M-55 gene from urinary tract infections patients in China

    PubMed Central

    Xia, Liang; Liu, Yang; Xia, Shu; Kudinha, Timothy; Xiao, Shu-nian; Zhong, Nan-shan; Ren, Guo-sheng; Zhuo, Chao

    2017-01-01

    To study molecular epidemiology of CTX-M-55-carrying Escherichia coli isolates from urinary tract infections (UTIs) in China. 111 blaCTX-M-55-positive E.coli isolates from UTIs patients in China were studied. Pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST) were used to analyze the homologies among the strains. Conjugation experiments, S1nuclease PFGE and PCR analysis were performed to characterize plasmids harboring blaCTX-M-55 and their genetic environment. 111 isolates were clustered into 86 individual pulsotypes and three clusters by PFGE. Fifty-five (49.5%) of the isolates belonged to 8 STs. Most of the ST1193 isolates belonged to one PFGE cluster. Transconjugants (n = 45) derived from randomly selected blaCTX-M-55 donors (n = 58), were found to contain a single 90-kb conjugative plasmid, which mainly belonged to the IncI1 groups (34, 76%). Among the IncI1 plasmids, the blaCTX-M-55/IncI1/ST16 predominated (23/34, 68%). The blaTEM-1 and aac (3′)-II genes were frequently detected on the IncI1 plasmids, and the insertion of ISEcp1 or IS26 was observed at the 48 bp or 45 bp upstream of the start codon of blaCTX-M-55 gene. The dissemination of blaCTX-M-55 gene among E. coli UTI isolates, appeared to be due to both the major clonal lineage of ST1193 and the horizontal transfer of epidemic plasmid IncI1/ST16. PMID:28338012

  7. [Dose-dependent effect of locally administered sulprostone gel on serum luteal and placental hormones in cervix priming in the 1st trimester].

    PubMed

    Rath, W; Pitzel, L; Hilgers, R; Kuhn, W

    1989-01-01

    In a prospective, randomised study 30 primigravidae were treated with 25 micrograms, 50 mu, or 100 micrograms sulprostone gel in order to soften the cervix prior to first trimester termination of pregnancy. 10 multigravidae received only the gel vehicle tylose. For objective demonstration of the priming effect, the force required for dilatation of the cervical canal was measured in Newton by a special tonometer before prostaglandin (PG) application and before operation. Serum progesterone, 17-beta-estradiol and hP1 levels were determined radioimmunologically prior to PG application and at two-hours intervals until curettage. A sonographic examination for determing the vitality of the pregnancy was performed before PG administration and immediately before the surgical intervention. There were no significant differences in the primig effect between the 50 micrograms and 100 micrograms sulprostone-treated group; the application of 25 micrograms sulprostone was significantly less effective. After 100 micrograms sulprostone gel abortion occurred in 2 patients, 6 women showed a marked decrease in hPl concentrations, progesterone levels were found to be reduced to 31.6-78.7% and 17-beta-estradiol to 10-40% of the initial values before PG application. We found a close time correlation between the occurrence of contraction-induced lower abdominal pain and the fall in hormone concentrations. No abortions occurred in any of the patients treated with 50 micrograms sulprostone gel; in 9 women without clinical symptoms no significant changes of the hormone concentrations were observed. In contrast to the previously published literature our results indicate that effective cervical ripening can be achieved by this method without disturbance of the feto-placental unit and the trophoblast respectively.

  8. Uncertainty calculation in the RIO air quality interpolation model and aggregation to yearly average and exceedance probability taking into account the temporal auto-correlation.

    NASA Astrophysics Data System (ADS)

    Maiheu, Bino; Nele, Veldeman; Janssen, Stijn; Fierens, Frans; Trimpeneers, Elke

    2010-05-01

    RIO is an operational air quality interpolation model developed by VITO and IRCEL-CELINE and produces hourly maps for different pollutant concentrations such as O3, PM10 and NO2 measured in Belgium [1]. The RIO methodology consists of residual interpolation by Ordinary Kriging of the residuals of the measured concentrations and pre-determined trend functions which express the relation between land cover information derived from the CORINE dataset and measured time-averaged concentrations [2]. RIO is an important tool for the Flemish administration and is among others used to report, as is required by each member state, on the air quality status in Flanders to the European Union. We feel that a good estimate of the uncertainty of the yearly average concentration maps and the probability of norm-exceedance are both as important as the values themselves. In this contribution we will discuss the uncertainties specific to the RIO methodology, where we have both contributions from the Ordinary Kriging technique as well as the trend functions. Especially the parameterisation of the uncertainty w.r.t. the trend functions will be the key indicator for the degree of confidence the model puts into using land cover information for spatial interpolation of pollutant concentrations. Next, we will propose a method which enables us to calculate the uncertainty on the yearly average concentrations as well as the number of exceedance days, taking into account the temporal auto-correlation of the concentration fields. It is clear that the autocorrelation will have a strong impact on the uncertainty estimation [3] of yearly averages. The method we propose is based on a Monte Carlo technique that generates an ensemble of interpolation maps with the correct temporal auto-correlation structure. From a generated ensemble, the calculation of norm-exceedance probability at each interpolation location becomes quite straightforward. A comparison with the ad-hoc method proposed in [3], where

  9. Variability of Polychaete Secondary Production in Intertidal Creek Networks along a Stream-Order Gradient

    PubMed Central

    Chu, Tianjiang; Sheng, Qiang; Wang, Sikai; Wu, Jihua

    2014-01-01

    Dendritic tidal creek networks are important habitats for sustaining biodiversity and ecosystem functioning in salt marsh wetlands. To evaluate the importance of creek heterogeneity in supporting benthic secondary production, we assess the spatial distribution and secondary production of a representative polychaete species (Dentinephtys glabra) in creek networks along a stream-order gradient in a Yangtze River estuarine marsh. Density, biomass, and secondary production of polychaetes were found to be highest in intermediate order creeks. In high order (3rd and 4th) creeks, the density and biomass of D. glabra were higher in creek edge sites than in creek bottom sites, whereas the reverse was true for low order (1st and 2nd) creeks. Secondary production was highest in 2nd order creeks (559.7 mg AFDM m−2 year−1) and was ca. 2 folds higher than in 1st and 4th order creeks. Top fitting AIC models indicated that the secondary production of D. glabra was mainly associated with geomorphological characters including cross-sectional area and bank slope. This suggests that hydrodynamic forces are essential factors influencing secondary production of macrobenthos in salt marshes. This study emphasizes the importance of microhabitat variability when evaluating secondary production and ecosystem functions. PMID:24817092

  10. EDITORIAL: Special section: Selected papers from OMS'05, the 1st Topical Meeting of the European Optical Society on Optical Microsystems (OMS)

    NASA Astrophysics Data System (ADS)

    Rendina, Ivo; Fazio, Eugenio; Ferraro, Pietro

    2006-07-01

    OMS'05 is the first international conference wholly dedicated to optical microsystems. It was organized by the European Optical Society (EOS) in the frame of its international topical meeting activity and was held in Italy, September 2005, amidst the wonderful scenery of the Island of Capri. A possible definition of an optical microsystem is a complex system, able to perform one or more sensing and actuation functions, where optical devices are integrated in a smart way with electronic, mechanical and sensing components by taking advantage of the progress in micro- and nano-technologies. The increasing interest in this field arises from the expected applications that would significantly improve the quality of life. The list of possibilities offered by the optical microsystem enabling technologies is very long and seems to increase day by day. We are not only thinking about the next generation of optical telecommunication networks and computers, but also about low-cost, compact microsystems for environmental monitoring, in order to improve safety in the avionic and automotive fields, medical diagnostics and proteomic/genomic studies, or just finding general applications in several industrial fields. The goal of the conference was to involve scientists and young researchers from the main public and private laboratories, giving them the opportunity to present new scientific results and compare their know-how in the exciting and emerging field of optical microsystems. We believe that we succeeded in this. More than 200 scientists from all over the world attended the conference. We had more than 100 oral presentations and approximately 20 from the keynote lectures and invited speeches. It was an opportunity to define the most recent progress carried out in the field and to outline the possible road-map leading to the expected results in the industrial and social fields. We strongly believe that research and technology are closely interconnected at present and cannot

  11. One- and two-point velocity distribution functions and velocity autocorrelation functions for various Reynolds numbers in decaying homogeneous isotropic turbulence

    NASA Astrophysics Data System (ADS)

    Hosokawa, Iwao

    2007-01-01

    A decaying homogeneous isotropic turbulence is treated on the combined bases of the Kolmogorov hypothesis and the cross-independence hypothesis (for a closure of the Monin-Lundgren (ML) hierarchy of many-point velocity distributions) in turbulence. Similarity solutions for one- and two-point velocity distributions are obtained in the viscous, inertial and large-scale ranges of separation distance, from which we can give a reasonable picture of longitudinal and transverse velocity autocorrelation functions for any Reynolds number, even though they are distant from exact solutions of the infinite ML hierarchy. Possibility of non-similarity solutions with other reasonable and more realistic features is unveiled within the same theoretical framework. The cross-independence hypothesis is proved to be inconsistent with the Kolmogorov [1941b. Dissipation of energy in locally isotropic turbulence. Dokl. Akad. Nauk SSSR 32, 16-18.] theory in the inertial range. This is the main factor by which our special strategy (described in Introduction) is taken for solving this problem.

  12. Calculation of the false alarm in pure frequency detection due to zero crossings of a narrow-band process - The possibility of estimating its autocorrelation envelope

    NASA Astrophysics Data System (ADS)

    Hay, J.

    Consideration is given to problems of pure frequency detection in the magnetic recording of acoustic noise in the presence of zero crossings by sinusoidal reference waves and narrow-band random processes. The principle of the partial detection of a sine wave based on isochronous zero crossings near a given coherent sequence threshold is reviewed, and a track detection criterion is introduced. A model of the signal detection process is then presented based on a probabilistic description of zero crossings which permits the definition of the normalized duration of a coherent sequence of zero crossings, and the model is validated in an experimental study of a narrow band process centered at 3240 Hz. The probability of the simultaneous detection of two channels is also calculated. The application of the model to parasitic detection in a two-frequency code is considered. Attention is then given to the relation between the isochronism of the coherent sequences of zero crossings and spectral sharpness, and a means for the direct estimation of the autocorrelation envelope of the narrowband noise process is derived.

  13. Velocity Change in the Zone of a Moderate Mw 5.0 Earthquake Revealed by Autocorrelations of Ambient Noise and by Event Spectra

    NASA Astrophysics Data System (ADS)

    von Seggern, David H.; Anderson, John G.

    2017-03-01

    A moderate Mw 5.0 earthquake occurred near Mogul, Nevada (just west of Reno, Nevada), on 26 April 2008. This mainshock was surrounded by notable foreshock and aftershock sequences. Due to the long foreshock sequence, the area was well instrumented at the time of the mainshock. We investigated the foreshock and aftershock sequences for evidence of velocity changes in the structure immediate to the hypocenter and above it in the area of observed strong ground motion. Using autocorrelations of the time periods with nearly continuous foreshocks and aftershocks, we detected a nearly 1% negative change in velocity on recordings of station MOGL which was approximately over the hypocenter of the mainshock. We also observed from these recordings a shift in the spectral peaks to lower frequency following the mainshock, again indicative of a velocity decrease. Due to the different spatial sampling of the two methods, the effects could not be attributed to the same subsurface volume. However, both results are strong evidence for coseismic velocity changes accompanying an earthquake which is very much smaller than those for which previous velocity changes have been reported. We hypothesize that these changes can be observed for even smaller earthquakes, given a fortuitous placement of observing stations.

  14. Determination of the normalized surface height autocorrelation function of a two-dimensional randomly rough dielectric surface by the inversion of light scattering data in p-polarization

    NASA Astrophysics Data System (ADS)

    Kryvi, J. B.; Simonsen, I.; Maradudin, A. A.

    2016-09-01

    The contribution to the mean differential reflection coefficient from the in-plane, co-polarized scattering of p- polarized light from a two-dimensional randomly rough dielectric surface is used to invert scattering data to obtain the normalized surface height autocorrelation function of the surface. Within phase perturbation theory this contribution to the mean differential reflection coefficient possesses singularities (poles) when the polar scattering angle θs equals +/-θB= +/- tan-1√E, where E is the dielectric constant of the dielectric medium and θB is the Brewster angle. Nevertheless, we show in this paper that if the mean differential reflection coefficient is measured only in the angular range |θs| < θB, these data can be inverted to yield accurate results for the normalized surface height correlation function for weakly rough surfaces. Several parameterized forms of this correlation function, and the minimization of a cost function with respect to the parameters defining these representations, are used in the inversion scheme. This approach also yields the rms height of the surface roughness, and the dielectric constant of the scattering medium if it is not known in advance. The input data used in this minimization procedure consist of computer simulation results for surfaces defined by exponential and Gaussian surface height correlation functions, without and with the addition of multiplicative noise. The proposed inversion scheme is computationally efficient.

  15. Computation and analysis of the transverse current autocorrelation function, Ct(k,t), for small wave vectors: A molecular-dynamics study for a Lennard-Jones fluid

    NASA Astrophysics Data System (ADS)

    Vogelsang, R.; Hoheisel, C.

    1987-02-01

    Molecular-dynamics (MD) calculations are reported for three thermodynamic states of a Lennard-Jones fluid. Systems of 2048 particles and 105 integration steps were used. The transverse current autocorrelation function, Ct(k,t), has been determined for wave vectors of the range 0.5<||k||σ<1.5. Ct(k,t) was fitted by hydrodynamic-type functions. The fits returned k-dependent decay times and shear viscosities which showed a systematic behavior as a function of k. Extrapolation to the hydrodynamic region at k=0 gave shear viscosity coefficients in good agreement with direct Green-Kubo results obtained in previous work. The two-exponential model fit for the memory function proposed by other authors does not provide a reasonable description of the MD results, as the fit parameters show no systematic wave-vector dependence, although the Ct(k,t) functions are somewhat better fitted. Similarly, the semiempirical interpolation formula for the decay time based on the viscoelastic concept proposed by Akcasu and Daniels fails to reproduce the correct k dependence for the wavelength range investigated herein.

  16. Variable Order and Distributed Order Fractional Operators

    NASA Technical Reports Server (NTRS)

    Lorenzo, Carl F.; Hartley, Tom T.

    2002-01-01

    Many physical processes appear to exhibit fractional order behavior that may vary with time or space. The continuum of order in the fractional calculus allows the order of the fractional operator to be considered as a variable. This paper develops the concept of variable and distributed order fractional operators. Definitions based on the Riemann-Liouville definitions are introduced and behavior of the operators is studied. Several time domain definitions that assign different arguments to the order q in the Riemann-Liouville definition are introduced. For each of these definitions various characteristics are determined. These include: time invariance of the operator, operator initialization, physical realization, linearity, operational transforms. and memory characteristics of the defining kernels. A measure (m2) for memory retentiveness of the order history is introduced. A generalized linear argument for the order q allows the concept of "tailored" variable order fractional operators whose a, memory may be chosen for a particular application. Memory retentiveness (m2) and order dynamic behavior are investigated and applications are shown. The concept of distributed order operators where the order of the time based operator depends on an additional independent (spatial) variable is also forwarded. Several definitions and their Laplace transforms are developed, analysis methods with these operators are demonstrated, and examples shown. Finally operators of multivariable and distributed order are defined in their various applications are outlined.

  17. Tigecycline Nonsusceptibility Occurs Exclusively in Fluoroquinolone-Resistant Escherichia coli Clinical Isolates, Including the Major Multidrug-Resistant Lineages O25b:H4-ST131-H30R and O1-ST648.

    PubMed

    Sato, Toyotaka; Suzuki, Yuuki; Shiraishi, Tsukasa; Honda, Hiroyuki; Shinagawa, Masaaki; Yamamoto, Soh; Ogasawara, Noriko; Takahashi, Hiroki; Takahashi, Satoshi; Tamura, Yutaka; Yokota, Shin-Ichi

    2017-02-01

    Tigecycline (TGC) is a last-line drug for multidrug-resistant Enterobacteriaceae We investigated the mechanism(s) underlying TGC nonsusceptibility (TGC resistant/intermediate) in Escherichia coli clinical isolates. The MIC of TGC was determined for 277 fluoroquinolone-susceptible isolates (ciprofloxacin [CIP] MIC, <0.125 mg/liter) and 194 fluoroquinolone-resistant isolates (CIP MIC, >2 mg/liter). The MIC50 and MIC90 for TGC in fluoroquinolone-resistant isolates were 2-fold higher than those in fluoroquinolone-susceptible isolates (MIC50, 0.5 mg/liter versus 0.25 mg/liter; MIC90, 1 mg/liter versus 0.5 mg/liter, respectively). Two fluoroquinolone-resistant isolates (O25b:H4-ST131-H30R and O125:H37-ST48) were TGC resistant (MICs of 4 and 16 mg/liter, respectively), and four other isolates of O25b:H4-ST131-H30R and an isolate of O1-ST648 showed an intermediate interpretation (MIC, 2 mg/liter). No TGC-resistant/intermediate strains were found among the fluoroquinolone-susceptible isolates. The TGC-resistant/intermediate isolates expressed higher levels of acrA and acrB and had lower intracellular TGC concentrations than susceptible isolates, and they possessed mutations in acrR and/or marR The MICs of acrAB-deficient mutants were markedly lower (0.25 mg/liter) than those of the parental strain. After continuous stepwise exposure to CIP in vitro, six of eight TGC-susceptible isolates had reduced TGC susceptibility. Two of them acquired TGC resistance (TGC MIC, 4 mg/liter) and exhibited expression of acrA and acrB and mutations in acrR and/or marR In conclusion, a population of fluoroquinolone-resistant E. coli isolates, including major extraintestinal pathogenic lineages O25b:H4-ST131-H30R and O1-ST648, showed reduced susceptibility to TGC due to overexpression of the efflux pump AcrAB-TolC, leading to decreased intracellular concentrations of the antibiotics that may be associated with the development of fluoroquinolone resistance.

  18. International Symposium on Polymer Electrolytes (1st)

    DTIC Science & Technology

    1987-06-01

    PULYPHOSPHAZENE-CROWN ETHERS A series of polyphosphazenes with pendant crown ethers have been prepared . A 16-crown-5 unit was attached to the poly phosphazene...linked to the low cationic transport numbers persisted, as was to be expected. We decided to prepare and test similar networks in which the ionic (or...electrolytes in battery set-up. Finally, suggestions will be put forward concerning the preparation of better ionomeric networks. REFERENCES I - P.V. WRIGHT

  19. Dewarless Logging Tool - 1st Generation

    SciTech Connect

    HENFLING,JOSEPH A.; NORMANN,RANDY A.

    2000-08-01

    This report focuses on Sandia National Laboratories' effort to create high-temperature logging tools for geothermal applications without the need for heat shielding. One of the mechanisms for failure in conventional downhole tools is temperature. They can only survive a limited number of hours in high temperature environments. For the first time since the evolution of integrated circuits, components are now commercially available that are qualified to 225 C with many continuing to work up to 300 C. These components are primarily based on Silicon-On-Insulator (SOI) technology. Sandia has developed and tested a simple data logger based on this technology that operates up to 300 C with a few limiting components operating to only 250 C without thermal protection. An actual well log to 240 C without shielding is discussed. The first prototype high-temperature tool measures pressure and temperature using a wire-line for power and communication. The tool is based around the HT83C51 microcontroller. A brief discussion of the background and status of the High Temperature Instrumentation program at Sandia, objectives, data logger development, and future project plans are given.

  20. 2014 Female Athlete Triad Coalition Consensus Statement on Treatment and Return to Play of the Female Athlete Triad: 1st International Conference held in San Francisco, California, May 2012 and 2nd International Conference held in Indianapolis, Indiana, May 2013.

    PubMed

    De Souza, Mary Jane; Nattiv, Aurelia; Joy, Elizabeth; Misra, Madhusmita; Williams, Nancy I; Mallinson, Rebecca J; Gibbs, Jenna C; Olmsted, Marion; Goolsby, Marci; Matheson, Gordon

    2014-02-01

    The Female Athlete Triad is a medical condition often observed in physically active girls and women, and involves three components: (1) low energy availability with or without disordered eating, (2) menstrual dysfunction and (3) low bone mineral density. Female athletes often present with one or more of the three Triad components, and an early intervention is essential to prevent its progression to serious endpoints that include clinical eating disorders, amenorrhoea and osteoporosis. This consensus statement represents a set of recommendations developed following the 1st (San Francisco, California, USA) and 2nd (Indianapolis, Indiana, USA) International Symposia on the Female Athlete Triad. It is intended to provide clinical guidelines for physicians, athletic trainers and other healthcare providers for the screening, diagnosis and treatment of the Female Athlete Triad and to provide clear recommendations for return to play. The 2014 Female Athlete Triad Coalition Consensus Statement on Treatment and Return to Play of the Female Athlete Triad expert panel has proposed a risk stratification point system that takes into account magnitude of risk to assist the physician in decision-making regarding sport participation, clearance and return to play. Guidelines are offered for clearance categories, management by a multidisciplinary team and implementation of treatment contracts. This consensus paper has been endorsed by the Female Athlete Triad Coalition, an International Consortium of leading Triad researchers, physicians and other healthcare professionals, the American College of Sports Medicine and the American Medical Society for Sports Medicine.

  1. [Experimental models of diabetes mellitus of the 1st and 2nd types in rats: regulation of activity of glycogen synthase by peptides of the insulin superfamily and by epidermal growth factor in skeletal muscles].

    PubMed

    Kuznetsova, L A; Chistiakova, O V

    2012-01-01

    The regulatory effect of peptides of the insulin hyperfamily--insulin, insulin-like growth factor (IGF-1), and relaxin, as well as of epidermal growth factor (EGF) on activity of glycogen synthase (GS) in rat skeletal muscles was studied in norm and in experimental diabetes mellitus of the 1st and 2nd types (DM1, DM2). In norm, peptides in vitro stimulated maximally the GS activity at a concentration of 10-8 M. The row of efficiency of the peptide action was as follows: insulin > IGF-1 > relaxin. In DM1 the basal GS activity did not change, while effect of insulin in vitro was decreased more sharply as compared with action of IGF-1 and relaxin at the 30th day of development of diabetes, i. e., the efficiency row was as follows: IGF-1 = relaxin > insulin. Administration of insulin in vivo did not restore sensitivity of the enzyme to the action of hormone in DM1. In DM2, the GS activity (both the total and active form) decreased. while the stimulatory effect ofpeptides and EGF on the enzyme was absent. Insulin introduced in vitro did not lead to restoration of the enzyme reaction. The conclusion has been made that the insulin resistance affects the basal GS activity in rat skeletal muscles as well as the regulation of the enzyme by peptides of the insulin nature and by EGF, which is more obvious in DM2, than in DM1.

  2. Highly ordered self-assembled nanoscale periodic faceting in GaAs(631) homoepitaxial growth

    NASA Astrophysics Data System (ADS)

    Cruz-Hernández, E.; Shimomura, S.; Méndez-García, V. H.

    2012-08-01

    We report on the self-assembly of large-order-correlated nanoscale faceting on GaAs(631)A substrates grown by molecular beam epitaxy. The surface morphology of the grown samples as a function of the growth temperature and the As-beam equivalent pressure was studied using atomic force microscopy. A two-dimensional autocorrelation function analysis was performed in order to quantitatively determine the uniformity of the surface corrugation. By optimizing the growth conditions, correlated faceted areas as large as 1.7 × 1.7 μm2 are obtained. The highly ordered surface corrugation discussed here provides useful insights to prepare highly ordered facet planes for the self organized growth of quantum wires.

  3. Mono-static GPR without transmitting anything for pavement damage inspection: interferometry by auto-correlation applied to mobile phone signals

    NASA Astrophysics Data System (ADS)

    Feld, R.; Slob, E. C.; Thorbecke, J.

    2015-12-01

    Creating virtual sources at locations where physical receivers have measured a response is known as seismic interferometry. A much appreciated benefit of interferometry is its independence of the actual source locations. The use of ambient noise as actual source is therefore not uncommon in this field. Ambient noise can be commercial noise, like for example mobile phone signals. For GPR this can be useful in cases where it is not possible to place a source, for instance when it is prohibited by laws and regulations. A mono-static GPR antenna can measure ambient noise. Interferometry by auto-correlation (AC) places a virtual source on this antenna's position, without actually transmitting anything. This can be used for pavement damage inspection. Earlier work showed very promising results with 2D numerical models of damaged pavement. 1D and 2D heterogeneities were compared, both modelled in a 2D pavement world. In a 1D heterogeneous model energy leaks away to the sides, whereas in a 2D heterogeneous model rays can reflect and therefore still add to the signal reconstruction (see illustration). In the first case the amount of stationary points is strictly limited, while in the other case the amount of stationary points is very large. We extend these models to a 3D world and optimise an experimental configuration. The illustration originates from the journal article under submission 'Non-destructive pavement damage inspection by mono-static GPR without transmitting anything' by R. Feld, E.C. Slob, and J.W. Thorbecke. (a) 2D heterogeneous pavement model with three irregular-shaped misalignments between the base and subbase layer (marked by arrows). Mono-antenna B-scan positions are shown schematically. (b) Ideal output: a real source at the receiver's position. The difference w.r.t. the trace found in the middle is shown. (c) AC output: a virtual source at the receiver's position. There is a clear overlap with the ideal output.

  4. A Theory for Market Impact: How Order Flow Affects Stock Price

    NASA Astrophysics Data System (ADS)

    Gerig, Austin

    2008-04-01

    It is known that the impact of transactions on stock price (market impact) is a concave function of the size of the order, but there exists little quantitative theory that suggests why this is so. I develop a quantitative theory for the market impact of hidden orders (orders that reflect the true intention of buying and selling) that matches the empirically measured result and that reproduces some of the non-trivial and universal properties of stock returns (returns are percent changes in stock price). The theory is based on a simple premise, that the stock market can be modeled in a mechanical way - as a device that translates order flow into an uncorrelated price stream. Given that order flow is highly autocorrelated, this premise requires that market impact (1) depends on past order flow and (2) is asymmetric for buying and selling. I derive the specific form for the dependence in (1) by assuming that current liquidity responds to information about all currently active hidden orders (liquidity is a measure of the price response to a transaction of a given size). This produces an equation that suggests market impact should scale logarithmically with total order size. Using data from the London Stock Exchange I empirically measure market impact and show that the result matches the theory. Also using empirical data, I qualitatively specify the asymmetry of (2). Putting all results together, I form a model for market impact that reproduces three universal properties of stock returns - that returns are uncorrelated, that returns are distributed with a power law tail, and that the magnitude of returns is highly autocorrelated (also known as clustered volatility).

  5. Reduced order modeling of aeroelasticity analysis for a wing under static deformation effect

    NASA Astrophysics Data System (ADS)

    Tamayama, Masato

    2017-01-01

    The full order analysis of aeroelasticity system, which solves the Euler or Navier Stokes equations in a time domain, is usually expensive in a sense of time consumed. To improve this situation, the Reduced Order Modeling (ROM) method has been developed. If there is a pressure difference between upper and lower surfaces of a wing, the aerodynamic forces loaded on the wing cause static deformations. The ROM, therefore, should have a capability to simulate wing vibrations under the static deformation effect. To include this effect, sequential processing of ROMs for two times is proposed in this study. The 1st step ROM predicts the flutter condition for the rigid wing. The 2nd step ROM predicts the flutter condition for the statically deformed wing under the aerodynamic load caused by the 1st step ROM flutter dynamic pressure. The accuracy of this method is verified by comparing the results with those predicted only by the full order analysis. In this study, the identification of aerodynamic forces is conducted by the Eigensystem Realization Algorithm (ERA). In the ERA, reduction of singular value matrix influences the accuracy of identification. Two methods are introduced to reduce the singular value matrix, and the flutter conditions acquired by these two methods are compared each other.

  6. 78 FR 54234 - Antidumping or Countervailing Duty Order, Finding, or Suspended Investigation; Advance...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-03

    ... Polyethylene Terephthalate (Pet) Film from Dana Mermelstein (202) Brazil (A-351-841) (1st Review). 482-1391. Polyethylene Terephthalate (Pet) Film from China Dana Mermelstein (202) (A-570-924) (1st Review). 482-1391... Terephthalate (Pet) Film from Dana Mermelstein United Arab Emirates (1st Review) (A-520-803)....

  7. Density functional theory calculations on the active site of biotin synthase: mechanism of S transfer from the Fe(2)S(2) cluster and the role of 1st and 2nd sphere residues.

    PubMed

    Rana, Atanu; Dey, Subal; Agrawal, Amita; Dey, Abhishek

    2015-10-01

    Density functional theory (DFT) calculations are performed on the active site of biotin synthase (BS) to investigate the sulfur transfer from the Fe(2)S(2) cluster to dethiobiotin (DTB). The active site is modeled to include both the 1st and 2nd sphere residues. Molecular orbital theory considerations and calculation on smaller models indicate that only an S atom (not S²⁻) transfer from an oxidized Fe(2)S(2) cluster leads to the formation of biotin from the DTB using two adenosyl radicals generated from S-adenosyl-L-methionine. The calculations on larger protein active site model indicate that a 9-monothiobiotin bound reduced cluster should be an intermediate during the S atom insertion from the Fe(2)S(2) cluster consistent with experimental data. The Arg260 bound to Fe1, being a weaker donor than cysteine bound to Fe(2), determines the geometry and the electronic structure of this intermediate. The formation of this intermediate containing the C9-S bond is estimated to have a ΔG(≠) of 17.1 kcal/mol while its decay by the formation of the 2nd C6-S bond is calculated to have a ΔG(≠) of 29.8 kcal/mol, i.e. the 2nd C-S bond formation is calculated to be the rate determining step in the cycle and it leads to the decay of the Fe(2)S(2) cluster. Significant configuration interaction (CI), present in these transition states, helps lower the barrier of these reactions by ~30-25 kcal/mol relative to a hypothetical outer-sphere reaction. The conserved Phe285 residue near the Fe(2)S(2) active site determines the stereo selectivity at the C6 center of this radical coupling reaction. Reaction mechanism of BS investigated using DFT calculations. Strong CI and the Phe285 residue control the kinetic rate and stereochemistry of the product.

  8. Results of Primary Total Hip Arthroplasty Using 36 mm Femoral Heads on 1st Generation Highly Cross Linked Polyethylene in Patients 50 Years and Less with Minimum Five Year Follow-up

    PubMed Central

    Choi, Won-Kee; Kim, Hee-soo; Nam, Jun-Ho; Chae, Seung-Bum

    2016-01-01

    Purpose We evaluated the clinical and radiographic midterm results of primary total hip arthroplasty (THA) using a 36 mm diameter femoral head on 1st generation highly cross-linked polyethylene (HXLPE) in patients 50 years and less with minimum five year follow-up. Materials and Methods We retrospectively reviewed 31 patients (41 hips) aged 50 years and less underwent primary THA with a 36 mm diameter femoral head on HXLPE between 2004 and 2010. Clinical follow-ups included specific measurements like modified Harris hip scores (HHS) and Merle d'Aubigne and Postel score. For radiologic evaluations, together with position of acetabular cup at six weeks later of postoperation, we separately calculated the penentrations of femoral head into polyethylene liners during postoperation and one year later check-ups, and during one year later check-ups and final check-ups. Results There were no major complications except for one case of dislocation. Average modified HHS at final follow-up was 88 (81-98), and Merle d'Aubigne and Postel scores were more than 15. Mean acetabular cup inclination and anteversion were 45.81°(36.33°-54.91°) and 13.26°(6.72°-27.71°), respectively. Average femoral head penetration of steady-state wear rate determined using radiographs taken at one-year postoperatively and at latest follow-up was 0.042±0.001 mm/year. Conclusion Based on minimum 5 years clinical results, we think 36 mm metal head coupling with HXLPE as the good alternate articulation surface when planning THA for patients aged 50 years and less. PMID:27536648

  9. Critical comparison of several order-book models for stock-market fluctuations

    NASA Astrophysics Data System (ADS)

    Slanina, F.

    2008-01-01

    Far-from-equilibrium models of interacting particles in one dimension are used as a basis for modelling the stock-market fluctuations. Particle types and their positions are interpreted as buy and sel orders placed on a price axis in the order book. We revisit some modifications of well-known models, starting with the Bak-Paczuski-Shubik model. We look at the four decades old Stigler model and investigate its variants. One of them is the simplified version of the Genoa artificial market. The list of studied models is completed by the models of Maslov and Daniels et al. Generically, in all cases we compare the return distribution, absolute return autocorrelation and the value of the Hurst exponent. It turns out that none of the models reproduces satisfactorily all the empirical data, but the most promising candidates for further development are the Genoa artificial market and the Maslov model with moderate order evaporation.

  10. Order Theoretical Semantic Recommendation

    SciTech Connect

    Joslyn, Cliff A.; Hogan, Emilie A.; Paulson, Patrick R.; Peterson, Elena S.; Stephan, Eric G.; Thomas, Dennis G.

    2013-07-23

    Mathematical concepts of order and ordering relations play multiple roles in semantic technologies. Discrete totally ordered data characterize both input streams and top-k rank-ordered recommendations and query output, while temporal attributes establish numerical total orders, either over time points or in the more complex case of startend temporal intervals. But also of note are the fully partially ordered data, including both lattices and non-lattices, which actually dominate the semantic strcuture of ontological systems. Scalar semantic similarities over partially-ordered semantic data are traditionally used to return rank-ordered recommendations, but these require complementation with true metrics available over partially ordered sets. In this paper we report on our work in the foundations of partial order measurement in ontologies, with application to top-k semantic recommendation in workflows.

  11. Ecosystem functional assessment based on the "optical type" concept and self-similarity patterns: An application using MODIS-NDVI time series autocorrelation

    NASA Astrophysics Data System (ADS)

    Huesca, Margarita; Merino-de-Miguel, Silvia; Eklundh, Lars; Litago, Javier; Cicuéndez, Victor; Rodríguez-Rastrero, Manuel; Ustin, Susan L.; Palacios-Orueta, Alicia

    2015-12-01

    Remote sensing (RS) time series are an excellent operative source for information about the land surface across several scales and different levels of landscape heterogeneity. Ustin and Gamon (2010) proposed the new concept of "optical types" (OT), meaning "optically distinguishable functional types", as a way to better understand remote sensing signals related to the actual functional behavior of species that share common physiognomic forms but differ in functionality. Whereas the OT approach seems to be promising and consistent with ecological theory as a way to monitor vegetation derived from RS, it received little implementation. This work presents a method for implementing the OT concept for efficient monitoring of ecosystems based on RS time series. We propose relying on an ecosystem's repetitive pattern in the temporal domain (self-similarity) to assess its dynamics. Based on this approach, our main hypothesis is that distinct dynamics are intrinsic to a specific OT. Self-similarity level in the temporal domain within a broadleaf forest class was quantitatively assessed using the auto-correlation function (ACF), from statistical time series analysis. A vector comparison classification method, spectral angle mapper, and principal component analysis were used to identify general patterns related to forest dynamics. Phenological metrics derived from MODIS NDVI time series using the TIMESAT software, together with information from the National Forest Map were used to explain the different dynamics found. Results showed significant and highly stable self-similarity patterns in OTs that corresponded to forests under non-moisture-limited environments with an adaptation strategy based on a strong phenological synchrony with climate seasonality. These forests are characterized by dense closed canopy deciduous forests associated with high productivity and low biodiversity in terms of dominant species. Forests in transitional areas were associated with patterns of less

  12. Surface Roughness and Critical Exponent Analyses of Boron-Doped Diamond Films Using Atomic Force Microscopy Imaging: Application of Autocorrelation and Power Spectral Density Functions

    NASA Astrophysics Data System (ADS)

    Gupta, S.; Vierkant, G. P.

    2014-09-01

    The evolution of the surface roughness of growing metal or semiconductor thin films provides much needed information about their growth kinetics and corresponding mechanism. While some systems show stages of nucleation, coalescence, and growth, others exhibit varying microstructures for different process conditions. In view of these classifications, we report herein detailed analyses based on atomic force microscopy (AFM) characterization to extract the surface roughness and growth kinetics exponents of relatively low boron-doped diamond (BDD) films by utilizing the analytical power spectral density (PSD) and autocorrelation function (ACF) as mathematical tools. The machining industry has applied PSD for a number of years for tool design and analysis of wear and machined surface quality. Herein, we present similar analyses at the mesoscale to study the surface morphology as well as quality of BDD films grown using the microwave plasma-assisted chemical vapor deposition technique. PSD spectra as a function of boron concentration (in gaseous phase) are compared with those for samples grown without boron. We find that relatively higher boron concentration yields higher amplitudes of the longer-wavelength power spectral lines, with amplitudes decreasing in an exponential or power-law fashion towards shorter wavelengths, determining the roughness exponent ( α ≈ 0.16 ± 0.03) and growth exponent ( β ≈ 0.54), albeit indirectly. A unique application of the ACF, which is widely used in signal processing, was also applied to one-dimensional or line analyses (i.e., along the x- and y-axes) of AFM images, revealing surface topology datasets with varying boron concentration. Here, the ACF was used to cancel random surface "noise" and identify any spatial periodicity via repetitive ACF peaks or spatially correlated noise. Periodicity at shorter spatial wavelengths was observed for no doping and low doping levels, while smaller correlations were observed for relatively

  13. Ab initio molecular dynamics study of ethylene adsorption onto Si(001) surface: short-time Fourier transform analysis of structural coordinate autocorrelation function.

    PubMed

    Lee, Yung Ting; Lin, Jyh Shing

    2013-12-05

    The reaction dynamics of ethylene adsorption onto the Si(001) surface have been studied by combining density functional theory-based molecular dynamics simulations with molecular adsorption sampling scheme for investigating all kinds of reaction pathways and corresponding populations. Based on the calculated results, three possible reaction pathways--the indirect adsorption, the direct adsorption, and the repelling reaction--have been found. First, the indirect adsorption, in which the ethylene (C2H(4(ads))) forms the π-bonded C2H(4(ads)) with the buckled-down Si atom to adsorb on the Si(001) surface and then turns into the di-σ-bonded C2H(4(ads)), is the major reaction pathway. The short-time Fourier transform analysis of structural coordinate autocorrelation function is performed to further investigate the evolution of different vibrational modes along this indirect reaction pathway. This analysis illustrates that the Infrared (IR) inactive peak of the C=C stretching mode of the π-bonded C2 H4(ads) shifts to the IR inactive peak of the C-C stretching mode of di-σ-bonded C2H(4(ads)), which is in a good agreement with the IR inactive peak of the C=C stretching mode vanished in the vibrational spectrum at 150 K (Nagao et al., J. Am. Chem. Soc. 2004, 126, 9922). Second, the direct adsorption, in which the di-σ-bonded C2H(4(ads)) is formed directly with the Si intradimer or the Si interdimer on the Si(001) surface, is the less significant reaction pathway. This reaction pathway leads to the C-C stretching mode and the C-H stretching mode of the di-σ-bonded C2H(4(ads)) appeared in the vibrational spectra at 48 and 150 K, respectively (Nagao et al., J. Am. Chem. Soc. 2004, 126, 9922). Finally, the repelling reaction, in which the C2H(4(g)) first interacts with the Si dimer and then is repelled by Si atoms, is the least important reaction pathway. Consequently, neither the π-bonded C2H(4(ads)) nor the di-σ-bonded C2H(4(ads)) is formed on the Si(001) surface.

  14. Reduced-order autoregressive modeling for center-frequency estimation.

    PubMed

    Kuc, R; Li, H

    1985-07-01

    The center frequency of a narrowband, discrete-time random process, such as a reflected ultrasound signal, is estimated from the parameter values of a reduced, second-order autoregressive (AR) model. This approach is proposed as a fast estimator that performs better than the zero-crossing count estimate for determining the center-frequency location. The parameter values are obtained through a linear prediction analysis on the correlated random process, which in this case is identical to the maximum entropy method for spectral estimation. The frequency of the maximum of the second-order model spectrum is determined from these parameters and is used as the center-frequency estimate. This estimate can be computed very efficiently, requiring only the estimates of the first three terms of the process autocorrelation function. The bias and variance properties of this estimator are determined for a random process having a Gaussian-shaped spectrum and compared to those of the ideal FM frequency discriminator, zero-crossing count estimator and a correlation estimator. It is found that the variance values for the reduced-order AR model center-frequency estimator lie between those for the ideal FM frequency discriminator and the zero-crossing count estimator.

  15. Higher-order phase shift reconstruction approach

    SciTech Connect

    Cong Wenxiang; Wang Ge

    2010-10-15

    Purpose: Biological soft tissues encountered in clinical and preclinical imaging mainly consists of atoms of light elements with low atomic numbers and their elemental composition is nearly uniform with little density variation. Hence, x-ray attenuation contrast is relatively poor and cannot achieve satisfactory sensitivity and specificity. In contrast, x-ray phase-contrast provides a new mechanism for soft tissue imaging. The x-ray phase shift of soft tissues is about a thousand times greater than the x-ray absorption over the diagnostic x-ray energy range, yielding a higher signal-to-noise ratio than the attenuation contrast counterpart. Thus, phase-contrast imaging is a promising technique to reveal detailed structural variation in soft tissues, offering a high contrast resolution between healthy and malignant tissues. Here the authors develop a novel phase retrieval method to reconstruct the phase image on the object plane from the intensity measurements. The reconstructed phase image is a projection of the phase shift induced by an object and serves as input to reconstruct the 3D refractive index distribution inside the object using a tomographic reconstruction algorithm. Such x-ray refractive index images can reveal structural features in soft tissues, with excellent resolution differentiating healthy and malignant tissues. Methods: A novel phase retrieval approach is proposed to reconstruct an x-ray phase image of an object based on the paraxial Fresnel-Kirchhoff diffraction theory. A primary advantage of the authors' approach is higher-order accuracy over that with the conventional linear approximation models, relaxing the current restriction of slow phase variation. The nonlinear terms in the autocorrelation equation of the Fresnel diffraction pattern are eliminated using intensity images measured at different distances in the Fresnel diffraction region, simplifying the phase reconstruction to a linear inverse problem. Numerical experiments are performed

  16. Minimal Orderings Revisited

    SciTech Connect

    Peyton, B.W.

    1999-07-01

    When minimum orderings proved too difficult to deal with, Rose, Tarjan, and Leuker instead studied minimal orderings and how to compute them (Algorithmic aspects of vertex elimination on graphs, SIAM J. Comput., 5:266-283, 1976). This paper introduces an algorithm that is capable of computing much better minimal orderings much more efficiently than the algorithm in Rose et al. The new insight is a way to use certain structures and concepts from modern sparse Cholesky solvers to re-express one of the basic results in Rose et al. The new algorithm begins with any initial ordering and then refines it until a minimal ordering is obtained. it is simple to obtain high-quality low-cost minimal orderings by using fill-reducing heuristic orderings as initial orderings for the algorithm. We examine several such initial orderings in some detail.

  17. First-order inflation

    SciTech Connect

    Kolb, E.W. Chicago Univ., IL . Enrico Fermi Inst.)

    1990-09-01

    In the original proposal, inflation occurred in the process of a strongly first-order phase transition. This model was soon demonstrated to be fatally flawed. Subsequent models for inflation involved phase transitions that were second-order, or perhaps weakly first-order; some even involved no phase transition at all. Recently the possibility of inflation during a strongly first-order phase transition has been revived. In this talk I will discuss some models for first-order inflation, and emphasize unique signatures that result in inflation is realized in a first-order transition. Before discussing first-order inflation, I will briefly review some of the history of inflation to demonstrate how first-order inflation differs from other models. 58 refs., 3 figs.

  18. ASDC Ordering Tool

    Atmospheric Science Data Center

    2017-02-08

    ... Ordering requires login , searching does not. Projects by science discipline: Aerosols | Clouds | Radiation Budget ... Tropospheric Composition | Field Campaigns All projects Details:  ASDC Ordering Tool ...

  19. Infants Communicate in Order to Be Understood

    ERIC Educational Resources Information Center

    Grosse, Gerlind; Behne, Tanya; Carpenter, Malinda; Tomasello, Michael

    2010-01-01

    Infants intentionally communicate with others from before their 1st birthday. But there is some question about how they understand the communicative process. Do they understand that for their request to work the recipient must both understand the request and be cooperatively disposed to fulfill it? On the basis of the study by Shwe and Markman…

  20. Infant temperament: stability by age, gender, birth order, term status, and socioeconomic status.

    PubMed

    Bornstein, Marc H; Putnick, Diane L; Gartstein, Maria A; Hahn, Chun-Shin; Auestad, Nancy; O'Connor, Deborah L

    2015-01-01

    Two complementary studies focused on stability of infant temperament across the 1st year and considered infant age, gender, birth order, term status, and socioeconomic status (SES) as moderators. Study 1 consisted of 73 mothers of firstborn term girls and boys queried at 2, 5, and 13 months of age. Study 2 consisted of 335 mothers of infants of different gender, birth order, term status, and SES queried at 6 and 12 months. Consistent positive and negative affectivity factors emerged at all time points across both studies. Infant temperament proved stable and robust across gender, birth order, term status, and SES. Stability coefficients for temperament factors and scales were medium to large for shorter (< 9 months) interassessment intervals and small to medium for longer (> 10 months) intervals.

  1. Modeling anomalous radar propagation using first-order two-state Markov chains

    NASA Astrophysics Data System (ADS)

    Haddad, B.; Adane, A.; Mesnard, F.; Sauvageot, H.

    In this paper, it is shown that radar echoes due to anomalous propagations (AP) can be modeled using Markov chains. For this purpose, images obtained in southwestern France by means of an S-band meteorological radar recorded every 5 min in 1996 were considered. The daily mean surfaces of AP appearing in these images are sorted into two states and their variations are then represented by a binary random variable. The Markov transition matrix, the 1-day-lag autocorrelation coefficient as well as the long-term probability of having each of both states are calculated on a monthly basis. The same kind of modeling was also applied to the rainfall observed in the radar dataset under study. The first-order two-state Markov chains are then found to fit the daily variations of either AP or rainfall areas very well. For each month of the year, the surfaces filled by both types of echo follow similar stochastic distributions, but their autocorrelation coefficient is different. Hence, it is suggested that this coefficient is a discriminant factor which could be used, among other criteria, to improve the identification of AP in radar images.

  2. New archaeomagnetic data recovered from the study of celtiberic remains from central Spain (Numantia and Ciadueña, 3rd-1st centuries BC). Implications on the fidelity of the Iberian paleointensity database

    NASA Astrophysics Data System (ADS)

    Osete, M. L.; Chauvin, A.; Catanzariti, G.; Jimeno, A.; Campuzano, S. A.; Benito-Batanero, J. P.; Tabernero-Galán, C.; Roperch, P.

    2016-11-01

    Variations of geomagnetic field in the Iberian Peninsula prior to roman times are poorly constrained. Here we report new archaeomagnetic results from four ceramic collections and two combustion structures recovered in two pre-roman (celtiberic) archaeological sites in central Spain. The studied materials have been dated by archaeological evidences and supported by five radiocarbon dates. Rock magnetic experiments indicate that the characteristic remanent manetization (ChRM) is carried by a low coercivity magnetic phase with Curie temperatures of 530-575 °C, most likely Ti-poor titanomagnetite/titanomaghemite. Archaeointensity determinations were carried out by using the classical Thellier-Thellier protocol including tests and corrections for magnetic anisotropy and cooling rate dependency. Two magnetic behaviours were depicted during the laboratory treatment. Black potsherds and poor heated samples from the kilns, presented two magnetization components, alterations or curved Arai plots and were therefore rejected. In contrast, well heated specimens (red ceramic fragments and well heated samples from the kilns) show one single well defined component of magnetization going through the origin and linear Arai plots providing successful archaeointensity determinations. The effect of anisotropy of the thermoremanent magnetization (ATRM) on paleointensity analysis was systematically investigated obtaining very high ATRM corrections on fine pottery specimens. In some cases, differences between the uncorrected and ATRM corrected paleointensity values reached up to 86 %. The mean intensity values obtained from three selected set of samples were 64.3 ± 5.8 μT; 56.8 ± 3.8 and 56.7 ± 4.6 μT (NUS2, CI2 and CIA, respectively), which contribute to better understand the evolution of the palaeofield intensity in central Iberia during the 3rd-1st centuries BC. The direction of the field at first century BC has also been determined from oriented samples from CIA kilns (D = 357

  3. Characterizing limit order prices

    NASA Astrophysics Data System (ADS)

    Withanawasam, R. M.; Whigham, P. A.; Crack, Timothy Falcon

    2013-11-01

    A computational model of a limit order book is used to study the effect of different limit order distribution offsets. Reference prices such as same side/contra side best market prices and last traded price are considered in combination with different price offset distributions. We show that when characterizing limit order prices, varying the offset distribution only produces different behavior when the reference price is the contra side best price. Irrespective of the underlying mechanisms used in computing the limit order prices, the shape of the price graph and the behavior of the average order book profile distribution are strikingly similar in all the considered reference prices/offset distributions. This implies that existing averaging methods can cancel variabilities in limit order book shape/attributes and may be misleading.

  4. Complete Sequence of pEC012, a Multidrug-Resistant IncI1 ST71 Plasmid Carrying bla CTX-M-65, rmtB, fosA3, floR, and oqxAB in an Avian Escherichia coli ST117 Strain.

    PubMed

    Pan, Yu-Shan; Zong, Zhi-Yong; Yuan, Li; Du, Xiang-Dang; Huang, Hui; Zhong, Xing-Hao; Hu, Gong-Zheng

    2016-01-01

    A 139,622-bp IncI1 ST71 conjugative plasmid pEC012 from an avian Escherichia coli D-ST117 strain was sequenced, which carried five IS26-bracketed resistance modules: IS26-fosA3-orf1-orf2-Δorf3-IS26, IS26-fip-ΔISEcp1-bla CTX-M-65-IS903D-iroN-IS26, IS26-ΔtnpR-bla TEM-1-rmtB-IS26, IS26-oqxAB-IS26, and IS26-floR-aac(3)-IV-IS26. The backbone of pEC012 was similar to that of several other IncI1 ST71 plasmids: pV408, pM105, and pC271, but these plasmids had different arrangements of multidrug resistance region. In addition, the novel ISEc57 element was identified, which is in the IS21 family. The stepwise emergence of multi-resistance regions demonstrated the accumulation of different resistance determinants through homologous recombination. To the best of our knowledge, this is the first study to identify a multidrug-resistant IncI1 ST71 plasmid carrying bla CTX-M-65, rmtB, fosA3, floR, and oqxAB in an avian E. coli ST117 strain.

  5. Complete Sequence of pEC012, a Multidrug-Resistant IncI1 ST71 Plasmid Carrying blaCTX-M-65, rmtB, fosA3, floR, and oqxAB in an Avian Escherichia coli ST117 Strain

    PubMed Central

    Pan, Yu-Shan; Zong, Zhi-Yong; Yuan, Li; Du, Xiang-Dang; Huang, Hui; Zhong, Xing-Hao; Hu, Gong-Zheng

    2016-01-01

    A 139,622-bp IncI1 ST71 conjugative plasmid pEC012 from an avian Escherichia coli D-ST117 strain was sequenced, which carried five IS26-bracketed resistance modules: IS26-fosA3-orf1-orf2-Δorf3-IS26, IS26-fip-ΔISEcp1-blaCTX-M-65-IS903D-iroN-IS26, IS26-ΔtnpR-blaTEM-1-rmtB-IS26, IS26-oqxAB-IS26, and IS26-floR-aac(3)-IV-IS26. The backbone of pEC012 was similar to that of several other IncI1 ST71 plasmids: pV408, pM105, and pC271, but these plasmids had different arrangements of multidrug resistance region. In addition, the novel ISEc57 element was identified, which is in the IS21 family. The stepwise emergence of multi-resistance regions demonstrated the accumulation of different resistance determinants through homologous recombination. To the best of our knowledge, this is the first study to identify a multidrug-resistant IncI1 ST71 plasmid carrying blaCTX-M-65, rmtB, fosA3, floR, and oqxAB in an avian E. coli ST117 strain. PMID:27486449

  6. Multiple ordering in magnetite.

    NASA Technical Reports Server (NTRS)

    Cullen, J. R.; Callen, E. R.

    1973-01-01

    Results of a self-consistent band calculation of the ground-state energy and charge orderings based on a tight-binding scheme in magnetite are presented. They show that below a critical (about 2.2) value of the ratio of interatomic Coulomb energy to bandwidth the lowest energy state has no order. Between this critical value and 2.5, the preferred state is multiply ordered.

  7. Narcissism and birth order.

    PubMed

    Eyring, W E; Sobelman, S

    1996-04-01

    The purpose of this investigation was to clarify the relationship between birth-order position and the development of narcissism, while refining research and theory. The relationship between birth-order status and narcissism was examined with a sample of 79 undergraduate students (55 women and 24 men). These subjects were placed in one of the four following birth-order categories of firstborn, second-born, last-born, and only children. These categories were chosen given their significance in Adlerian theory. Each subject completed the Narcissistic Personality Inventory and a demographic inventory. Based on psychodynamic theory, it was hypothesized that firstborn children were expected to score highest, but statistical significance was not found for an association between narcissism and birth order. Further research is urged to investigate personality theory as it relates to parenting style and birth order.

  8. On mechanisms triggering the levees failure along the Foenna stream on 1st January 2006 and which caused the flooding in the urban area of Sinalunga, Tuscany Region (Italy). A case study

    NASA Astrophysics Data System (ADS)

    Camici, Stefania; Moramarco, Tommaso; Brocca, Luca; Melone, Florisa; Lapenna, Vincenzo; Perrone, Angela; Loperte, Antonio

    2010-05-01

    On 1st January 2006, during an ordinary flood event, a levee failure along the Foenna stream caused the flooding in the urban area of Sinalunga, a small town located in Tuscany region (Italy). The event was monitored by a public agency with the responsibility for the control and maintenance of the natural channel networks. Long time before of flooding, people living in the surrounding area of the stream blamed the presence of wild animals and of numerous burrows along the levees. Although the numerous actions of maintenance along the levees mainly for removing the burrows, a levee seepage occurred during that flood. The presence of an outflow located on the downstream face, almost 2 m below the levee top, caused the spurt of brown water denoting the presence of sediment erosion. On the upstream face of levee, a little hole of about 30 cm at the same height of the outflow was discovered. Although the agency workers tried to close the hole by using appropriate blankets, in short time the top of the levee subsided and the overtopping flow caused a trapezoidal breach typical for an earth-fill embankment. The formation of breach was so fast that in a little more of one hour the urban area near to the Foenna stream was flooded causing high economic damages. Mechanisms triggered the levees failure are the object of this work. The analysis of the event has been first addressed to assess the state of-fact of levees conditions along the Foenna stream, thus to understand how much the activity of wild animals, in particular that of porcupine, may have affected the hydraulic safety of the embankment. At the purpose, after the event, topographical surveys of cross sections have been done along with tomographic surveys by geoelectric technique for investigating the possible presence, besides of burrows, also of tunnels dug into the levees by animals. Then, the analysis of hydrometeorological conditions of the event has allowed to better understand the evolution of the flood and

  9. ASDC Order Tools

    Atmospheric Science Data Center

    2012-04-17

    ... users to search our data holdings without logging in to the system. The user, however, must log in before ordering the data. ... Cavity Radiometer Irradiance Monitor II (ACRIM II) Total Solar Irradiance Data Global Tropospheric Experiment (GTE) data (Selected ...

  10. Court Ordered Desegregation

    ERIC Educational Resources Information Center

    Reber, Sarah J.

    2005-01-01

    The effect of the court ordered desegregation plans, on trends in segregation and white flight, are estimated. The effect of availability of school districts and other factors on the white flight across districts is also mentioned.

  11. Arguments from Developmental Order

    PubMed Central

    Stöckle-Schobel, Richard

    2016-01-01

    In this article1, I investigate a special type of argument regarding the role of development in theorizing about psychological processes and cognitive capacities. Among the issues that developmental psychologists study, discovering the ontogenetic trajectory of mechanisms or capacities underpinning our cognitive functions ranks highly. The order in which functions are developed or capacities are acquired is a matter of debate between competing psychological theories, and also philosophical conceptions of the mind – getting the role and the significance of the different steps in this order right could be seen as an important virtue of such theories. Thus, a special kind of strategy in arguments between competing philosophical or psychological theories is using developmental order in arguing for or against a given psychological claim. In this article, I will introduce an analysis of arguments from developmental order, which come in two general types: arguments emphasizing the importance of the early cognitive processes and arguments emphasizing the late cognitive processes. I will discuss their role in one of the central tools for evaluating scientific theories, namely in making inferences to the best explanation. I will argue that appeal to developmental order is, by itself, an insufficient criterion for theory choice and has to be part of an argument based on other core explanatory or empirical virtues. I will end by proposing a more concerted study of philosophical issues concerning (cognitive) development, and I will present some topics that also pertain to a full-fledged ‘philosophy of development.’ PMID:27242648

  12. Concomitant Ordering and Symmetry Lowering

    ERIC Educational Resources Information Center

    Boo, William O. J.; Mattern, Daniell L.

    2008-01-01

    Examples of concomitant ordering include magnetic ordering, Jahn-Teller cooperative ordering, electronic ordering, ionic ordering, and ordering of partially-filled sites. Concomitant ordering sets in when a crystal is cooled and always lowers the degree of symmetry of the crystal. Concomitant ordering concepts can also be productively applied to…

  13. Spatially ordered treemaps.

    PubMed

    Wood, Jo; Dykes, Jason

    2008-01-01

    Existing treemap layout algorithms suffer to some extent from poor or inconsistent mappings between data order and visual ordering in their representation, reducing their cognitive plausibility. While attempts have been made to quantify this mismatch, and algorithms proposed to minimize inconsistency, solutions provided tend to concentrate on one-dimensional ordering. We propose extensions to the existing squarified layout algorithm that exploit the two-dimensional arrangement of treemap nodes more effectively. Our proposed spatial squarified layout algorithm provides a more consistent arrangement of nodes while maintaining low aspect ratios. It is suitable for the arrangement of data with a geographic component and can be used to create tessellated cartograms for geovisualization. Locational consistency is measured and visualized and a number of layout algorithms are compared. CIELab color space and displacement vector overlays are used to assess and emphasize the spatial layout of treemap nodes. A case study involving locations of tagged photographs in the Flickr database is described.

  14. Mobile physician order entry.

    PubMed

    Ying, Alan

    2003-01-01

    Because both computerized physician order entry (CPOE) systems and mobile technologies such as handheld devices have the potential to greatly impact the industry's future, IT vendors, hospitals, and clinicians are simply merging them into a logical convergence--"CPOE on a handheld"--with an expectation of full functionality on all platforms: computer workstations, rolling laptops, tablet PCs, and handheld devices. For these trends to succeed together, however, this expectation must be revised to establish a distinct category--mobile physician order entry (MPOE)--that is different from CPOE in form, function, and implementation.

  15. Court-ordered caesareans.

    PubMed

    Prochaska, Elizabeth; Lomri, Sara

    2014-11-01

    Court-ordered caesarean sections are in the news after a number of recent legal decisions authorising surgery for women who lack mental capacity to consent. The decisions have not always been based on good evidence and they raise serious concerns about the protection of the rights of mentally ill women. The authors explain the legal process and question the wisdom of recent judgements.

  16. Land and World Order.

    ERIC Educational Resources Information Center

    Mische, Patricia, Ed.; And Others

    1982-01-01

    The papers in this publication discuss the land and how what happens to the land affects us. The publication is one in a series of monographs that examine the linkages between local and global concerns and explore alternative world futures. Examples of topics discussed in the papers follow. The paper "Land and World Order" examines…

  17. Education and World Order

    ERIC Educational Resources Information Center

    Jones, Phillip W.

    2007-01-01

    The impact on educational analysis of mainstream international relations (IR) theories is yet to realize its full potential. The problem of education in relation to the construction of world order is considered in relation to core developments in IR theory since the Second World War. In particular, the global architecture of education is seen as a…

  18. Birth Order Debate Resolved?

    ERIC Educational Resources Information Center

    Zajonc, R. B.

    2001-01-01

    Critiques Rodgers et al.'s June 2000 research on the relation between birth order and intelligence, which suggests that it is a methodological illusion. Explains how the intellectual environment and the teaching function (whereby older children tutor younger ones) contribute to the growth of intellectual maturity, the first negatively and the…

  19. The Birth Order Puzzle.

    ERIC Educational Resources Information Center

    Zajonc, R. B.; And Others

    1979-01-01

    Discusses the controversy of the relationship between birth order and intellectual performance through a detailed evaluation of the confluence model which assumes that the rate of intellectual growth is a function of the intellectual environment within the family and associated with the special circumstances of last children. (CM)

  20. Pansedik: Ordering Creative Chaos.

    ERIC Educational Resources Information Center

    Austin, Barbara L.

    1998-01-01

    Presents a case study for use in business communication classes to help students understand and learn both the context and the strategies for communication with business and management. Deals with a new human resource director's attempt to bring order to an organization and software developers' concerns over their work being hindered. Includes two…