Sample records for linking time periods

  1. Time-Varying Periodicity in Intraday Volatility

    DEFF Research Database (Denmark)

    Andersen, Torben Gustav; Thyrsgaard, Martin; Todorov, Viktor

    We develop a nonparametric test for deciding whether return volatility exhibits time-varying intraday periodicity using a long time-series of high-frequency data. Our null hypothesis, commonly adopted in work on volatility modeling, is that volatility follows a stationary process combined...... with a constant time-of-day periodic component. We first construct time-of-day volatility estimates and studentize the high-frequency returns with these periodic components. If the intraday volatility periodicity is invariant over time, then the distribution of the studentized returns should be identical across...... with estimating volatility moments through their sample counterparts. Critical values are computed via easy-to-implement simulation. In an empirical application to S&P 500 index returns, we find strong evidence for variation in the intraday volatility pattern driven in part by the current level of volatility...

  2. Forecasting with periodic autoregressive time series models

    NARCIS (Netherlands)

    Ph.H.B.F. Franses (Philip Hans); R. Paap (Richard)


    textabstractThis paper is concerned with forecasting univariate seasonal time series data using periodic autoregressive models. We show how one should account for unit roots and deterministic terms when generating out-of-sample forecasts. We illustrate the models for various quarterly UK consumption

  3. True Time API Link (real time arrival info) (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This link will take you to the site where you can create an account to access Port Authority's real time arrival information. To request access to Port Authority's...

  4. The RHIC real time data link system

    International Nuclear Information System (INIS)

    Hartmann, H.


    The RHIC Real Time Data Link (RTDL) System distributes to all locations around the RHIC ring machine parameters of general interest to accelerator systems and users. The system, along with supporting host interface, is centrally located. The RTDL System is comprised of two module types: the Encoder Module (V105) and the Input Module (V106). There is only one V105 module, but many (up to 128) Input Modules. Multiple buffered outputs are provided for use locally or for retransmission to other RHIC equipment locations. Machine parameters are generated from the V115 Waveform Generator Module (WFG) or from machine hardware and coupled directly through a fiber optic serial link to one of the V106 input channels

  5. A novel time series link prediction method: Learning automata approach (United States)

    Moradabadi, Behnaz; Meybodi, Mohammad Reza


    Link prediction is a main social network challenge that uses the network structure to predict future links. The common link prediction approaches to predict hidden links use a static graph representation where a snapshot of the network is analyzed to find hidden or future links. For example, similarity metric based link predictions are a common traditional approach that calculates the similarity metric for each non-connected link and sort the links based on their similarity metrics and label the links with higher similarity scores as the future links. Because people activities in social networks are dynamic and uncertainty, and the structure of the networks changes over time, using deterministic graphs for modeling and analysis of the social network may not be appropriate. In the time-series link prediction problem, the time series link occurrences are used to predict the future links In this paper, we propose a new time series link prediction based on learning automata. In the proposed algorithm for each link that must be predicted there is one learning automaton and each learning automaton tries to predict the existence or non-existence of the corresponding link. To predict the link occurrence in time T, there is a chain consists of stages 1 through T - 1 and the learning automaton passes from these stages to learn the existence or non-existence of the corresponding link. Our preliminary link prediction experiments with co-authorship and email networks have provided satisfactory results when time series link occurrences are considered.

  6. 7 CFR 1.603 - How are time periods computed? (United States)


    ... 7 Agriculture 1 2010-01-01 2010-01-01 false How are time periods computed? 1.603 Section 1.603... Licenses General Provisions § 1.603 How are time periods computed? (a) General. Time periods are computed as follows: (1) The day of the act or event from which the period begins to run is not included. (2...

  7. 50 CFR 221.3 - How are time periods computed? (United States)


    ... 50 Wildlife and Fisheries 7 2010-10-01 2010-10-01 false How are time periods computed? 221.3... Provisions § 221.3 How are time periods computed? (a) General. Time periods are computed as follows: (1) The day of the act or event from which the period begins to run is not included. (2) The last day of the...

  8. On periodic orbits in discrete-time cascade systems

    Directory of Open Access Journals (Sweden)

    Huimin Li


    Full Text Available We present some results on existence, minimum period, number of periodic orbits, and stability of periodic orbits in discrete-time cascade systems. Some examples are presented to illustrate these results.

  9. Rainfall measurement using cell phone links: classification of wet and dry periods using geostationary satellites

    NARCIS (Netherlands)

    van Delden, A.J.; van het Schip, T.I.; Overeem, Aart; Leijnse, Hidde; Uijlenhoet, Remko; Meirink, J.F.


    Commercial cellular telecommunication networks can be used for rainfall estimation by measur- ing the attenuation of electromagnetic signals transmitted between antennas from microwave links. However, as the received link signal may also decrease during dry periods, a method to separate wet and dry

  10. Linking age, survival, and transit time distributions (United States)

    Calabrese, Salvatore; Porporato, Amilcare


    Although the concepts of age, survival, and transit time have been widely used in many fields, including population dynamics, chemical engineering, and hydrology, a comprehensive mathematical framework is still missing. Here we discuss several relationships among these quantities by starting from the evolution equation for the joint distribution of age and survival, from which the equations for age and survival time readily follow. It also becomes apparent how the statistical dependence between age and survival is directly related to either the age dependence of the loss function or the survival-time dependence of the input function. The solution of the joint distribution equation also allows us to obtain the relationships between the age at exit (or death) and the survival time at input (or birth), as well as to stress the symmetries of the various distributions under time reversal. The transit time is then obtained as a sum of the age and survival time, and its properties are discussed along with the general relationships between their mean values. The special case of steady state case is analyzed in detail. Some examples, inspired by hydrologic applications, are presented to illustrate the theory with the specific results. This article was corrected on 11 Nov 2015. See the end of the full text for details.

  11. 43 CFR 45.3 - How are time periods computed? (United States)


    ... 43 Public Lands: Interior 1 2010-10-01 2010-10-01 false How are time periods computed? 45.3... IN FERC HYDROPOWER LICENSES General Provisions § 45.3 How are time periods computed? (a) General... run is not included. (2) The last day of the period is included. (i) If that day is a Saturday, Sunday...

  12. Infant Mortality Statistics From the 2013 Period Linked Birth/Infant Death Data Set. (United States)

    Matthews, T J; MacDorman, Marian F; Thoma, Marie E


    This report presents 2013 period infant mortality statistics from the linked birth/infant death data set (linked file) by maternal and infant characteristics. The linked file differs from the mortality file, which is based entirely on death certificate data. Descriptive tabulations of data are presented and interpreted. The U.S. infant mortality rate was 5.96 infant deaths per 1,000 live births in 2013, similar to the rate of 5.98 in 2012. The number of infant deaths was 23,446 in 2013, a decline of 208 infant deaths from 2012. From 2012 to 2013, infant mortality rates were stable for most race and Hispanic origin groups; declines were reported for two Hispanic subgroups: Cuban and Puerto Rican. Since 2005, the most recent high, the U.S. infant mortality rate has declined 13% (from 6.86), with declines in both neonatal and postneonatal mortality overall and for most groups. In 2013, infants born at 37–38 weeks of gestation (early term) had mortality rates that were 63% higher than for full-term (39–40 week) infants. For multiple births, the infant mortality rate was 25.84, 5 times the rate of 5.25 for singleton births. In 2013, 36% of infant deaths were due to preterm-related causes of death, and an additional 15% were due to causes grouped into the sudden unexpected infant death category. All material appearing in this report is in the public domain and may be reproduced or copied without permission; citation as to source, however, is appreciated.

  13. Periodic transients linked to a variation in reactivity; Transitoires de periode lies a une variation de reactivite

    Energy Technology Data Exchange (ETDEWEB)

    Furet, J; Weil, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires


    We study here the influence of the transient, linked to a variation in reactivity, on the measurement of the period, this measurement being made from the logarithmic differential of the power and being defined by 1/T 1/p(dp/dt). We show that the adjustment of the thresholds of period safety is often incompatible with the velocities of liberation of reactivity. A compromise is then necessary between the speed of response of the periodimeter and the speed with which the reactivity is liberated. This makes it necessary to have rapid security devices for the power levels in the piles in which the speeds of liberation of the reactivity are high. (author) [French] On etudie ici l'influence du transitoire lie a une variation de la reactivite sur la mesure de la periode, cette mesure etant faite a partir de la derivee logarithmique de la puissance et etant definie par 1/T 1/p(dp/dt). On montre que le reglage des seuils de securite periode est souvent incompatible avec les vitesses de liberation de reactivite. Il y a alors un compromis a faire entre la vitesse de reponse du periodemetre et la vitesse de liberation de reactivite. Ceci impose de disposer de securites rapides sur les niveaux de puissance, dans les piles ou les vitesses de liberation de reactivite sont importantes. (auteur)

  14. Direct method for the periodic amplification of a soliton in an optical fibre link with loss

    International Nuclear Information System (INIS)

    Li Lu; Xue Wenrui; Xu Zhiyong; Li Zhonghao; Zhou Guosheng


    A direct approach is applied to the periodic amplification of a soliton in an optical fibre link with loss. In a single soliton case, the adiabatic solution and first-order correction are given for the system. The apparent advantage of this direct approach is that it not only presents the slow evolution of soliton parameters, but also the perturbation-induced radiation, and can be easily used to investigate the system of dispersion management with periodically varying dispersion and other fields

  15. On positive periodic solution of periodic competition Lotka-Volterra system with time delay and diffusion

    International Nuclear Information System (INIS)

    Sun Wen; Chen Shihua; Hong Zhiming; Wang Changping


    A two-species periodic competition Lotka-Volterra system with time delay and diffusion is investigated. Some sufficient conditions of the existence of positive periodic solution are established for the system by using the continuation theorem of coincidence degree theory

  16. Finding time over time: Longitudinal links between employed mothers' work-family conflict and time profiles. (United States)

    Lee, Soomi; McHale, Susan M; Crouter, Ann C; Hammer, Leslie B; Almeida, David M


    Drawing upon the Work-Home Resources model (ten Brummelhuis & Bakker, 2012), this study examined the links between work-family conflict and employed mothers' profiles of time resources for work and parenting roles. Using a person-centered latent profile approach, we identified 3 profiles of time use and perceived time adequacy in a sample of mothers employed in the extended-care industry (N = 440): a Work-Oriented profile, characterized by spending relatively more time at work, perceiving lower time adequacy for work, spending less time with children, and perceiving lower time adequacy for children; a Parenting-Oriented profile, characterized by the opposite pattern; and a Role-Balanced profile, characterized by average levels across the 4 dimensions. Mothers in the Work-Oriented profile reported greater work-to-family conflict and family to-work conflict than those in the Role-Balanced and Parenting-Oriented profiles. Greater work-to-family conflict was linked to membership in the Work-Oriented profile, net of personal, family, and work characteristics. Longitudinal latent profile transition analysis showed that increases in work-to-family conflict across 12 months were linked to greater odds of moving toward the Work-Oriented profile (relative to staying in the same profile), whereas decreases in work-to-family conflict were linked to greater odds of moving toward the Parenting-Oriented profile. Results illuminate the heterogeneity in how employed mothers perceive and allocate time in work and parenting roles and suggest that decreasing work-to-family conflict may preserve time resources for parenting. Intervention efforts should address ways of increasing employees' family time resources and decreasing work-family conflict. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  17. Almost Periodicity in Time of Solutions of the Toda Lattice


    Binder, Ilia; Damanik, David; Lukic, Milivoje; VandenBoom, Tom


    We study an initial value problem for the Toda lattice with almost periodic initial data. We consider initial data for which the associated Jacobi operator is absolutely continuous and has a spectrum satisfying a Craig-type condition, and show the boundedness and almost periodicity in time and space of solutions.

  18. Periodic flows to chaos in time-delay systems

    CERN Document Server

    Luo, Albert C J


    This book for the first time examines periodic motions to chaos in time-delay systems, which exist extensively in engineering. For a long time, the stability of time-delay systems at equilibrium has been of great interest from the Lyapunov theory-based methods, where one cannot achieve the ideal results. Thus, time-delay discretization in time-delay systems was used for the stability of these systems. In this volume, Dr. Luo presents an accurate method based on the finite Fourier series to determine periodic motions in nonlinear time-delay systems. The stability and bifurcation of periodic motions are determined by the time-delayed system of coefficients in the Fourier series and the method for nonlinear time-delay systems is equivalent to the Laplace transformation method for linear time-delay systems. Facilitates discovery of analytical solutions of nonlinear time-delay systems; Illustrates bifurcation trees of periodic motions to chaos; Helps readers identify motion complexity and singularity; Explains pro...

  19. Relativistic helicity and link in Minkowski space-time

    International Nuclear Information System (INIS)

    Yoshida, Z.; Kawazura, Y.; Yokoyama, T.


    A relativistic helicity has been formulated in the four-dimensional Minkowski space-time. Whereas the relativistic distortion of space-time violates the conservation of the conventional helicity, the newly defined relativistic helicity conserves in a barotropic fluid or plasma, dictating a fundamental topological constraint. The relation between the helicity and the vortex-line topology has been delineated by analyzing the linking number of vortex filaments which are singular differential forms representing the pure states of Banach algebra. While the dimension of space-time is four, vortex filaments link, because vorticities are primarily 2-forms and the corresponding 2-chains link in four dimension; the relativistic helicity measures the linking number of vortex filaments that are proper-time cross-sections of the vorticity 2-chains. A thermodynamic force yields an additional term in the vorticity, by which the vortex filaments on a reference-time plane are no longer pure states. However, the vortex filaments on a proper-time plane remain to be pure states, if the thermodynamic force is exact (barotropic), thus, the linking number of vortex filaments conserves

  20. On time-periodic Navier-Stokes flows with fast spatial decay in the whole space

    Czech Academy of Sciences Publication Activity Database

    Nakatsuka, Tomoyuki


    Roč. 4, č. 1 (2018), s. 51-67 ISSN 2296-9020 Institutional support: RVO:67985840 Keywords : Navier-Stokes equation * time-periodic solution * asymptotic property Subject RIV: BA - General Mathematics OBOR OECD: Pure mathematics 1007 %2Fs41808-018-0011-8

  1. On time-periodic Navier-Stokes flows with fast spatial decay in the whole space

    Czech Academy of Sciences Publication Activity Database

    Nakatsuka, Tomoyuki


    Roč. 4, č. 1 (2018), s. 51-67 ISSN 2296-9020 Institutional support: RVO:67985840 Keywords : Navier-Stokes equation * time-periodic solution * asymptotic property Subject RIV: BA - General Mathematics OBOR OECD: Pure mathematics

  2. New serial time codes for seismic short period and long period data acquisition systems

    International Nuclear Information System (INIS)

    Kolvankar, V.G.; Rao, D.S.


    This paper discusses a new time code for time indexing multichannel short period (1 to 25 hz) seismic event data recorded on a single track of magnetic tape in digital format and discusses its usefulness in contrast to Vela time code used in continuous analog multichannel data recording system on multitrack instrumentation tape deck. This paper also discusses another time code, used for time indexing of seismic long period (DC to 2.5 seconds) multichannel data recorded on a single track of magnetic tape in digital format. The time code decoding and display system developed to provide quick access to any desired portion of the tape in both data recording and repro duce system is also discussed. (author). 7 figs

  3. Effective diffusion in time-periodic linear planar flow

    International Nuclear Information System (INIS)

    Indeikina, A.; Chang, H.


    It is shown that when a point source of solute is inserted into a time-periodic, unbounded linear planar flow, the large-time, time-average transport of the solute can be described by classical anisotropic diffusion with constant effective diffusion tensors. For a given vorticity and forcing period, elongational flow is shown to be the most dispersive followed by simple shear and rotational flow. Large-time diffusivity along the major axis of the time-average concentration ellipse, whose alignment is predicted from the theory, is shown to increase with vorticity for all flows and decrease with increasing forcing frequency for elongational flow and simple shear. For the interesting case of rotational flow, there exist discrete resonant frequencies where the time-average major diffusivity reaches local maxima equal to the time-average steady flow case with zero forcing frequency

  4. Real time control of the sawtooth period using EC launchers

    International Nuclear Information System (INIS)

    Paley, J I; Felici, F; Coda, S; Goodman, T P; Piras, F


    Tokamak plasmas operating at high performance are limited by several MHD instabilities. The sawtooth instability limits the core plasma pressure and can drive the neoclassical tearing mode unstable, but also prevents accumulation of impurities in the core. Electron cyclotron heating and current drive systems can be used to modify the local current profile and therefore tailor the sawtooth period. This paper reports on demonstrations of continuous real time feedback control of the sawtooth period by varying the EC injection angle.

  5. Time perspective: its link to personality traits, age, and gender


    Kairys, Antanas


    In Lithuania, as well as in other countries, psychological studies on time perspective are still making their first steps. Currently, no theoretical paradigm is extensive enough to serve well as a basis for further fundamental and applied research in this field. The goal of this study was to explore the link between time perspective and personality traits in different gender and age groups. To analyse time perspective and personality traits, two independent studies were carried out (N=636 in ...

  6. Period doubling phenomenon in a class of time delay equations

    International Nuclear Information System (INIS)

    Oliveira, C.R. de; Malta, C.P.


    The properties of the solution of a nonlinear time delayed differential equation (infinite dimension) as function of two parameters: the time delay tau and another parameter A (nonlinearity) are investigated. After a Hopf bifurcation period doubling may occur and is characterized by Feigenbaum's delta. A strange atractor is obtained after the period doubling cascade and the largest Lyapunov exponent is calculated indicating that the attractor has low dimension. The behaviour of this Liapunov exponent as function of tau is different from its behaviour as function of A. (Author) [pt

  7. Unsupervised action classification using space-time link analysis

    DEFF Research Database (Denmark)

    Liu, Haowei; Feris, Rogerio; Krüger, Volker


    In this paper we address the problem of unsupervised discovery of action classes in video data. Different from all existing methods thus far proposed for this task, we present a space-time link analysis approach which matches the performance of traditional unsupervised action categorization metho...

  8. 15 CFR 325.4 - Calculating time periods. (United States)


    ... 15 Commerce and Foreign Trade 2 2010-01-01 2010-01-01 false Calculating time periods. 325.4 Section 325.4 Commerce and Foreign Trade Regulations Relating to Commerce and Foreign Trade (Continued) INTERNATIONAL TRADE ADMINISTRATION, DEPARTMENT OF COMMERCE MISCELLANEOUS REGULATIONS EXPORT TRADE CERTIFICATES...

  9. Problems of Software Detection of Periodic Features in a Time ...

    African Journals Online (AJOL)

    Problems arise when attempts are made to extract automatically, visually obvious periodic features indicative of defects in a vibration time series for diagnosis using computers. Such problems may be interpretational in nature arising either from insufficient knowledge of the mechanism, or the convolution of the source signal ...

  10. Time-periodic solutions of the Benjamin-Ono equation

    Energy Technology Data Exchange (ETDEWEB)

    Ambrose , D.M.; Wilkening, Jon


    We present a spectrally accurate numerical method for finding non-trivial time-periodic solutions of non-linear partial differential equations. The method is based on minimizing a functional (of the initial condition and the period) that is positive unless the solution is periodic, in which case it is zero. We solve an adjoint PDE to compute the gradient of this functional with respect to the initial condition. We include additional terms in the functional to specify the free parameters, which, in the case of the Benjamin-Ono equation, are the mean, a spatial phase, a temporal phase and the real part of one of the Fourier modes at t = 0. We use our method to study global paths of non-trivial time-periodic solutions connecting stationary and traveling waves of the Benjamin-Ono equation. As a starting guess for each path, we compute periodic solutions of the linearized problem by solving an infinite dimensional eigenvalue problem in closed form. We then use our numerical method to continue these solutions beyond the realm of linear theory until another traveling wave is reached (or until the solution blows up). By experimentation with data fitting, we identify the analytical form of the solutions on the path connecting the one-hump stationary solution to the two-hump traveling wave. We then derive exact formulas for these solutions by explicitly solving the system of ODE's governing the evolution of solitons using the ansatz suggested by the numerical simulations.

  11. Time-periodic solutions of the Benjamin-Ono equation

    International Nuclear Information System (INIS)

    Ambrose, D.M.; Wilkening, Jon


    We present a spectrally accurate numerical method for finding non-trivial time-periodic solutions of non-linear partial differential equations. The method is based on minimizing a functional (of the initial condition and the period) that is positive unless the solution is periodic, in which case it is zero. We solve an adjoint PDE to compute the gradient of this functional with respect to the initial condition. We include additional terms in the functional to specify the free parameters, which, in the case of the Benjamin-Ono equation, are the mean, a spatial phase, a temporal phase and the real part of one of the Fourier modes at t = 0. We use our method to study global paths of non-trivial time-periodic solutions connecting stationary and traveling waves of the Benjamin-Ono equation. As a starting guess for each path, we compute periodic solutions of the linearized problem by solving an infinite dimensional eigenvalue problem in closed form. We then use our numerical method to continue these solutions beyond the realm of linear theory until another traveling wave is reached (or until the solution blows up). By experimentation with data fitting, we identify the analytical form of the solutions on the path connecting the one-hump stationary solution to the two-hump traveling wave. We then derive exact formulas for these solutions by explicitly solving the system of ODE's governing the evolution of solitons using the ansatz suggested by the numerical simulations

  12. Controlling mixing and segregation in time periodic granular flows (United States)

    Bhattacharya, Tathagata

    Segregation is a major problem for many solids processing industries. Differences in particle size or density can lead to flow-induced segregation. In the present work, we employ the discrete element method (DEM)---one type of particle dynamics (PD) technique---to investigate the mixing and segregation of granular material in some prototypical solid handling devices, such as a rotating drum and chute. In DEM, one calculates the trajectories of individual particles based on Newton's laws of motion by employing suitable contact force models and a collision detection algorithm. Recently, it has been suggested that segregation in particle mixers can be thwarted if the particle flow is inverted at a rate above a critical forcing frequency. Further, it has been hypothesized that, for a rotating drum, the effectiveness of this technique can be linked to the probability distribution of the number of times a particle passes through the flowing layer per rotation of the drum. In the first portion of this work, various configurations of solid mixers are numerically and experimentally studied to investigate the conditions for improved mixing in light of these hypotheses. Besides rotating drums, many studies of granular flow have focused on gravity driven chute flows owing to its practical importance in granular transportation and to the fact that the relative simplicity of this type of flow allows for development and testing of new theories. In this part of the work, we observe the deposition behavior of both mono-sized and polydisperse dry granular materials in an inclined chute flow. The effects of different parameters such as chute angle, particle size, falling height and charge amount on the mass fraction distribution of granular materials after deposition are investigated. The simulation results obtained using DEM are compared with the experimental findings and a high degree of agreement is observed. Tuning of the underlying contact force parameters allows the achievement

  13. Unstable Periodic Orbit Analysis of Histograms of Chaotic Time Series

    International Nuclear Information System (INIS)

    Zoldi, S.M.


    Using the Lorenz equations, we have investigated whether unstable periodic orbits (UPOs) associated with a strange attractor may predict the occurrence of the robust sharp peaks in histograms of some experimental chaotic time series. Histograms with sharp peaks occur for the Lorenz parameter value r=60.0 but not for r=28.0 , and the sharp peaks for r=60.0 do not correspond to a histogram derived from any single UPO. However, we show that histograms derived from the time series of a non-Axiom-A chaotic system can be accurately predicted by an escape-time weighting of UPO histograms. copyright 1998 The American Physical Society

  14. Time analysis in astronomy: Tools for periodicity searches

    International Nuclear Information System (INIS)

    Buccheri, R.; Sacco, B.


    The authors discuss periodicity searches in radio and gamma-ray astronomy with special considerations for pulsar searches. The basic methodologies of fast Fourier transform, Rayleigh test, and epoch folding are reviewed with the main objective to compare cost and sensitivities in different applications. It is found that FFT procedures are convenient in unbiased searches for periodicity in radio astronomy, while in spark chamber gamma-ray astronomy, where the measurements are spread over a long integration time, unbiased searches are very difficult with the existing computing facilities and analyses with a-priori knowledge on the period values to look for are better done using the Rayleigh test with harmonics folding (Z /sub n/ test)

  15. Computing return times or return periods with rare event algorithms (United States)

    Lestang, Thibault; Ragone, Francesco; Bréhier, Charles-Edouard; Herbert, Corentin; Bouchet, Freddy


    The average time between two occurrences of the same event, referred to as its return time (or return period), is a useful statistical concept for practical applications. For instance insurances or public agencies may be interested by the return time of a 10 m flood of the Seine river in Paris. However, due to their scarcity, reliably estimating return times for rare events is very difficult using either observational data or direct numerical simulations. For rare events, an estimator for return times can be built from the extrema of the observable on trajectory blocks. Here, we show that this estimator can be improved to remain accurate for return times of the order of the block size. More importantly, we show that this approach can be generalised to estimate return times from numerical algorithms specifically designed to sample rare events. So far those algorithms often compute probabilities, rather than return times. The approach we propose provides a computationally extremely efficient way to estimate numerically the return times of rare events for a dynamical system, gaining several orders of magnitude of computational costs. We illustrate the method on two kinds of observables, instantaneous and time-averaged, using two different rare event algorithms, for a simple stochastic process, the Ornstein–Uhlenbeck process. As an example of realistic applications to complex systems, we finally discuss extreme values of the drag on an object in a turbulent flow.

  16. Mimicking Nonequilibrium Steady States with Time-Periodic Driving (United States)


    construction does not require the solution of any differential equations , only linear algebraic equations . By contrast, a mapping in the opposite...set of algebraic linear equations . The mapping between NESS and SP presented above was not intended as a set of operational instructions for... differential equations with time-periodic parameters. Typically, this can only be done numerically. In some applications, transition rates are constrained by

  17. Periodic solutions in reaction–diffusion equations with time delay

    International Nuclear Information System (INIS)

    Li, Li


    Spatial diffusion and time delay are two main factors in biological and chemical systems. However, the combined effects of them on diffusion systems are not well studied. As a result, we investigate a nonlinear diffusion system with delay and obtain the existence of the periodic solutions using coincidence degree theory. Moreover, two numerical examples confirm our theoretical results. The obtained results can also be applied in other related fields

  18. A homomorphism between link and XXZ modules over the periodic Temperley–Lieb algebra

    International Nuclear Information System (INIS)

    Morin-Duchesne, Alexi; Saint-Aubin, Yvan


    We study finite loop models on a lattice wrapped around a cylinder. A section of the cylinder has N sites. We use a family of link modules over the periodic Temperley–Lieb algebra EPTL N (β,α) introduced by Martin and Saleur, and Graham and Lehrer. These are labeled by the numbers of sites N and of defects d, and extend the standard modules of the original Temperley–Lieb algebra. Besides the defining parameters β = u 2 + u −2 with u = e iλ/2 (weight of contractible loops) and α (weight of non-contractible loops), this family also depends on a twist parameter v that keeps track of how the defects wind around the cylinder. The transfer matrix T N (λ, ν) depends on the anisotropy ν and the spectral parameter λ that fixes the model. (The thermodynamic limit of T N is believed to describe conformal field theory of central charge c = 1 − 6λ 2 /(π(λ − π)).) The family of periodic XXZ Hamiltonians is extended to depend on this new parameter v, and the relationship between this family and the loop models is established. The Gram determinant for the natural bilinear form on these link modules is shown to factorize in terms of an intertwiner i-tilde N d between these link representations and the eigenspaces of S z of the XXZ models. This map is shown to be an isomorphism for generic values of u and v, and the critical curves in the plane of these parameters for which i-tilde N d fails to be an isomorphism are given. (paper)

  19. Periodicity and stability for variable-time impulsive neural networks. (United States)

    Li, Hongfei; Li, Chuandong; Huang, Tingwen


    The paper considers a general neural networks model with variable-time impulses. It is shown that each solution of the system intersects with every discontinuous surface exactly once via several new well-proposed assumptions. Moreover, based on the comparison principle, this paper shows that neural networks with variable-time impulse can be reduced to the corresponding neural network with fixed-time impulses under well-selected conditions. Meanwhile, the fixed-time impulsive systems can be regarded as the comparison system of the variable-time impulsive neural networks. Furthermore, a series of sufficient criteria are derived to ensure the existence and global exponential stability of periodic solution of variable-time impulsive neural networks, and to illustrate the same stability properties between variable-time impulsive neural networks and the fixed-time ones. The new criteria are established by applying Schaefer's fixed point theorem combined with the use of inequality technique. Finally, a numerical example is presented to show the effectiveness of the proposed results. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Space-time reference with an optical link

    International Nuclear Information System (INIS)

    Berceau, P; Hollberg, L; Taylor, M; Kahn, J


    We describe a concept for realizing a high performance space-time reference using a stable atomic clock in a precisely defined orbit and synchronizing the orbiting clock to high-accuracy atomic clocks on the ground. The synchronization would be accomplished using a two-way lasercom link between ground and space. The basic approach is to take advantage of the highest-performance cold-atom atomic clocks at national standards laboratories on the ground and to transfer that performance to an orbiting clock that has good stability and that serves as a ‘frequency-flywheel’ over time-scales of a few hours. The two-way lasercom link would also provide precise range information and thus precise orbit determination. With a well-defined orbit and a synchronized clock, the satellite could serve as a high-accuracy space-time reference, providing precise time worldwide, a valuable reference frame for geodesy, and independent high-accuracy measurements of GNSS clocks. Under reasonable assumptions, a practical system would be able to deliver picosecond timing worldwide and millimeter orbit determination, and could serve as an enabling subsystem for other proposed space-gravity missions, which are briefly reviewed. (paper)

  1. Relativistic Time Transfer for Inter-satellite Links

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Yi, E-mail: [Department of Astronomy, School of Astronomy and Space Sciences, Nanjing University, Nanjing (China); Shanghai Key Laboratory of Space Navigation and Position Techniques, Shanghai (China); Key Laboratory of Modern Astronomy and Astrophysics, Nanjing University, Ministry of Education, Nanjing (China)


    Inter-Satellite links (ISLs) will be an important technique for a global navigation satellite system (GNSS) in the future. Based on the principles of general relativity, the time transfer in an ISL is modeled and the algorithm for onboard computation is described. It is found, in general, satellites with circular orbits and identical semi-major axes can benefit inter-satellite time transfer by canceling out terms associated with the transformations between the proper times and the Geocentric Coordinate Time. For a GPS-like GNSS, the Shapiro delay is as large as 0.1 ns when the ISL passes at the limb of the Earth. However, in more realistic cases, this value will decrease to about 50 ps.

  2. Transient habitats limit development time for periodical cicadas. (United States)

    Karban, Richard


    Periodical cicadas (Magicicada spp.) mature in 13 or 17 years, the longest development times for any non-diapausing insects. Selection may favor prolonged development since nymphs experience little mortality and individuals taking 17 years have been shown to have greater fecundity than those taking 13 years. Why don't periodical cicadas take even longer to develop? Nymphs feed on root xylem fluid and move little. Ovipositing females prefer fast-growing trees at forest edges. I hypothesized that (1) adults emerging at edges would be heavier than those from forest interiors and (2) habitat changes could limit development time. I collected newly eclosed females that had neither fed as adults nor moved from their site of development. For M. septendecim, females from edges were 4.9% heavier than those from the interior. I assumed that emergence density indicated habitat quality and measured density at eight sites in 1979, 1996, and 2013. Over three generations, variation in densities was great; densities at two sites crashed, and at one site they exploded to 579/m2 Habitat transience may limit development time because only adults can reassess habitats and reposition offspring. In conclusion, cicadas are affected by habitat characteristics, habitats change over 17 years, and cicadas may emerge, mate, and redistribute their offspring to track habitat dynamics.

  3. Lagrangian structures in time-periodic vortical flows

    Directory of Open Access Journals (Sweden)

    S. V. Kostrykin


    Full Text Available The Lagrangian trajectories of fluid particles are experimentally studied in an oscillating four-vortex velocity field. The oscillations occur due to a loss of stability of a steady flow and result in a regular reclosure of streamlines between the vortices of the same sign. The Eulerian velocity field is visualized by tracer displacements over a short time period. The obtained data on tracer motions during a number of oscillation periods show that the Lagrangian trajectories form quasi-regular structures. The destruction of these structures is determined by two characteristic time scales: the tracers are redistributed sufficiently fast between the vortices of the same sign and much more slowly transported into the vortices of opposite sign. The observed behavior of the Lagrangian trajectories is quantitatively reproduced in a new numerical experiment with two-dimensional model of the velocity field with a small number of spatial harmonics. A qualitative interpretation of phenomena observed on the basis of the theory of adiabatic chaos in the Hamiltonian systems is given. The Lagrangian trajectories are numerically simulated under varying flow parameters. It is shown that the spatial-temporal characteristics of the Lagrangian structures depend on the properties of temporal change in the streamlines topology and on the adiabatic parameter corresponding to the flow. The condition for the occurrence of traps (the regions where the Lagrangian particles reside for a long time is obtained.

  4. Links between Patagonian Ice Sheet fluctuations and Antarctic dust variability during the last glacial period (MIS 4-2) (United States)

    Kaiser, Jérôme; Lamy, Frank


    Antarctic and Greenland ice-core records reveal large fluctuations of dust input on both orbital and millennial time-scales with potential global climate implications. At least during glacial periods, the Antarctic dust fluctuations appear to be largely controlled by environmental changes in southern South America. We compare dust flux records from two Antarctic ice-cores to variations in the composition of the terrigenous supply at ODP Site 1233 located off southern Chile and known to record fluctuations in the extent of the northern part of the Patagonian ice-sheet (NPIS) during the last glacial period (Marine Isotope Stage, MIS, 4 to 2). Within age uncertainties, millennial-scale glacial advances (retreats) of the NPIS correlate to Antarctic dust maxima (minima). In turn, NPIS fluctuations were closely related to offshore sea surface temperature (SST) changes. This pattern suggests a causal link involving changes in temperature, in rock flour availability, in latitudinal extensions of the westerly winds and in foehn winds in the southern Pampas and Patagonia. We further suggest that the long-term trend of dust accumulation is partly linked to the sea-level related changes in the size if the Patagonian source area due to the particular morphology of the Argentine shelf. We suggest that sea-level drops at the beginning of MIS 4 and MIS 2 were important for long-term dust increases, while changes in the Patagonian dust source regions primarily control the early dust decrease during the MIS 4/3 transition and Termination 1.

  5. A seesaw in Mediterranean precipitation during the Roman Period linked to millennial-scale changes in the North Atlantic (United States)

    Dermody, B. J.; de Boer, H. J.; Bierkens, M. F. P.; Weber, S. L.; Wassen, M. J.; Dekker, S. C.


    We present a reconstruction of the change in climatic humidity around the Mediterranean between 3000-1000 yr BP. Using a range of proxy archives and model simulations we demonstrate that climate during this period was typified by a millennial-scale seesaw in climatic humidity between Spain and Israel on one side and the Central Mediterranean and Turkey on the other, similar to precipitation anomalies associated with the East Atlantic/West Russia pattern in current climate. We find that changes in the position and intensity of the jet stream indicated by our analysis correlate with millennial changes in North Atlantic sea surface temperature. A model simulation indicates the proxies of climatic humidity used in our analysis were unlikely to be influenced by climatic aridification caused by deforestation during the Roman Period. That finding is supported by an analysis of the distribution of archaeological sites in the Eastern Mediterranean which exhibits no evidence that human habitation distribution changed since ancient times as a result of climatic aridification. Therefore we conclude that changes in climatic humidity over the Mediterranean during the Roman Period were primarily caused by a modification of the jet stream linked to sea surface temperature change in the North Atlantic. Based on our findings, we propose that ocean-atmosphere coupling may have contributed to regulating Atlantic Meridional Overturning Circulation intensity during the period of analysis.

  6. Unsupervised Ensemble Anomaly Detection Using Time-Periodic Packet Sampling (United States)

    Uchida, Masato; Nawata, Shuichi; Gu, Yu; Tsuru, Masato; Oie, Yuji

    We propose an anomaly detection method for finding patterns in network traffic that do not conform to legitimate (i.e., normal) behavior. The proposed method trains a baseline model describing the normal behavior of network traffic without using manually labeled traffic data. The trained baseline model is used as the basis for comparison with the audit network traffic. This anomaly detection works in an unsupervised manner through the use of time-periodic packet sampling, which is used in a manner that differs from its intended purpose — the lossy nature of packet sampling is used to extract normal packets from the unlabeled original traffic data. Evaluation using actual traffic traces showed that the proposed method has false positive and false negative rates in the detection of anomalies regarding TCP SYN packets comparable to those of a conventional method that uses manually labeled traffic data to train the baseline model. Performance variation due to the probabilistic nature of sampled traffic data is mitigated by using ensemble anomaly detection that collectively exploits multiple baseline models in parallel. Alarm sensitivity is adjusted for the intended use by using maximum- and minimum-based anomaly detection that effectively take advantage of the performance variations among the multiple baseline models. Testing using actual traffic traces showed that the proposed anomaly detection method performs as well as one using manually labeled traffic data and better than one using randomly sampled (unlabeled) traffic data.

  7. Urban Link Travel Time Prediction Based on a Gradient Boosting Method Considering Spatiotemporal Correlations

    Directory of Open Access Journals (Sweden)

    Faming Zhang


    Full Text Available The prediction of travel times is challenging because of the sparseness of real-time traffic data and the intrinsic uncertainty of travel on congested urban road networks. We propose a new gradient–boosted regression tree method to accurately predict travel times. This model accounts for spatiotemporal correlations extracted from historical and real-time traffic data for adjacent and target links. This method can deliver high prediction accuracy by combining simple regression trees with poor performance. It corrects the error found in existing models for improved prediction accuracy. Our spatiotemporal gradient–boosted regression tree model was verified in experiments. The training data were obtained from big data reflecting historic traffic conditions collected by probe vehicles in Wuhan from January to May 2014. Real-time data were extracted from 11 weeks of GPS records collected in Wuhan from 5 May 2014 to 20 July 2014. Based on these data, we predicted link travel time for the period from 21 July 2014 to 25 July 2014. Experiments showed that our proposed spatiotemporal gradient–boosted regression tree model obtained better results than gradient boosting, random forest, or autoregressive integrated moving average approaches. Furthermore, these results indicate the advantages of our model for urban link travel time prediction.

  8. Sextant: Visualizing time-evolving linked geospatial data

    NARCIS (Netherlands)

    C. Nikolaou (Charalampos); K. Dogani (Kallirroi); K. Bereta (Konstantina); G. Garbis (George); M. Karpathiotakis (Manos); K. Kyzirakos (Konstantinos); M. Koubarakis (Manolis)


    textabstractThe linked open data cloud is constantly evolving as datasets get continuously updated with newer versions. As a result, representing, querying, and visualizing the temporal dimension of linked data is crucial. This is especially important for geospatial datasets that form the backbone

  9. Real-time method of powder diffraction for non-periodic and nearly periodic materials

    International Nuclear Information System (INIS)

    Egami, T.; Toby, B.H.; Dmowski, T.W.; Jorgensen, J.D.


    The use of high-energy neutrons from pulsed or hot sources allows the method of atomic pair distribution analysis to be applied to the structural determination of crystalline as well as amorphous solids. This method complements the standard crystallographic methods in studying non-periodic aspects of solids with or without long range order. 14 refs., 3 figs

  10. Magnet Cycles and Stability Periods of the CMS Structures from 2008 to 2013 as Observed by the Link Alignment System

    International Nuclear Information System (INIS)

    Arce, P.; Barcala, J.M.; Calvo, E.; Ferrando, A.; Josa, M.I.; Molinero, A.; Navarrete, J.; Oller, J.C.


    In this document Magnet Cycles and Stability Periods of the CMS Experiment are studied with the recorded Alignment Link System data along the 2008 to 2013 years of operation. The motions of the mechanical structures due to the magnetic field forces are studied including an in-depth analysis of the relative distance between the endcap structures and the central Tracker body during the Stability Periods to verify the mechanical stability of the detector during the physics data taking.

  11. Long-time correlations of periodic, area-preserving maps

    International Nuclear Information System (INIS)

    Meiss, J.D.; Cary, J.R.; Grebogi, C.; Crawford, J.D.; Kaufman, A.N.; Abarbanel, H.D.I.


    A simple analytical decay law for correlation functions of periodic, area-preserving maps is obtained. This law is compared with numerical experiments on the standard map. The agreement between experiment and theory is good when islands are absent, but poor when islands are present. When islands are present, the correlations have a long, slowly decaying tail

  12. Logic Model Checking of Time-Periodic Real-Time Systems (United States)

    Florian, Mihai; Gamble, Ed; Holzmann, Gerard


    In this paper we report on the work we performed to extend the logic model checker SPIN with built-in support for the verification of periodic, real-time embedded software systems, as commonly used in aircraft, automobiles, and spacecraft. We first extended the SPIN verification algorithms to model priority based scheduling policies. Next, we added a library to support the modeling of periodic tasks. This library was used in a recent application of the SPIN model checker to verify the engine control software of an automobile, to study the feasibility of software triggers for unintended acceleration events.

  13. Periodic capacity management under a lead-time performance constraint

    NARCIS (Netherlands)

    Büyükkaramikli, N.C.; Bertrand, J.W.M.; Ooijen, van H.P.G.


    In this paper, we study a production system that operates under a lead-time performance constraint which guarantees the completion of an order before a pre-determined lead-time with a certain probability. The demand arrival times and the service requirements for the orders are random. To reduce the

  14. Multiresource allocation and scheduling for periodic soft real-time applications (United States)

    Gopalan, Kartik; Chiueh, Tzi-cker


    Real-time applications that utilize multiple system resources, such as CPU, disks, and network links, require coordinated scheduling of these resources in order to meet their end-to-end performance requirements. Most state-of-the-art operating systems support independent resource allocation and deadline-driven scheduling but lack coordination among multiple heterogeneous resources. This paper describes the design and implementation of an Integrated Real-time Resource Scheduler (IRS) that performs coordinated allocation and scheduling of multiple heterogeneous resources on the same machine for periodic soft real-time application. The principal feature of IRS is a heuristic multi-resource allocation algorithm that reserves multiple resources for real-time applications in a manner that can maximize the number of applications admitted into the system in the long run. At run-time, a global scheduler dispatches the tasks of the soft real-time application to individual resource schedulers according to the precedence constraints between tasks. The individual resource schedulers, which could be any deadline based schedulers, can make scheduling decisions locally and yet collectively satisfy a real-time application's performance requirements. The tightness of overall timing guarantees is ultimately determined by the properties of individual resource schedulers. However, IRS maximizes overall system resource utilization efficiency by coordinating deadline assignment across multiple tasks in a soft real-time application.

  15. Time-delayed feedback technique for suppressing instabilities in time-periodic flow (United States)

    Shaabani-Ardali, Léopold; Sipp, Denis; Lesshafft, Lutz


    A numerical method is presented that allows to compute time-periodic flow states, even in the presence of hydrodynamic instabilities. The method is based on filtering nonharmonic components by way of delayed feedback control, as introduced by Pyragas [Phys. Lett. A 170, 421 (1992), 10.1016/0375-9601(92)90745-8]. Its use in flow problems is demonstrated here for the case of a periodically forced laminar jet, subject to a subharmonic instability that gives rise to vortex pairing. The optimal choice of the filter gain, which is a free parameter in the stabilization procedure, is investigated in the context of a low-dimensional model problem, and it is shown that this model predicts well the filter performance in the high-dimensional flow system. Vortex pairing in the jet is efficiently suppressed, so that the unstable periodic flow state in response to harmonic forcing is accurately retrieved. The procedure is straightforward to implement inside any standard flow solver. Memory requirements for the delayed feedback control can be significantly reduced by means of time interpolation between checkpoints. Finally, the method is extended for the treatment of periodic problems where the frequency is not known a priori. This procedure is demonstrated for a three-dimensional cubic lid-driven cavity in supercritical conditions.

  16. Using travel times to simulate multi-dimensional bioreactive transport in time-periodic flows. (United States)

    Sanz-Prat, Alicia; Lu, Chuanhe; Finkel, Michael; Cirpka, Olaf A


    In travel-time models, the spatially explicit description of reactive transport is replaced by associating reactive-species concentrations with the travel time or groundwater age at all locations. These models have been shown adequate for reactive transport in river-bank filtration under steady-state flow conditions. Dynamic hydrological conditions, however, can lead to fluctuations of infiltration velocities, putting the validity of travel-time models into question. In transient flow, the local travel-time distributions change with time. We show that a modified version of travel-time based reactive transport models is valid if only the magnitude of the velocity fluctuates, whereas its spatial orientation remains constant. We simulate nonlinear, one-dimensional, bioreactive transport involving oxygen, nitrate, dissolved organic carbon, aerobic and denitrifying bacteria, considering periodic fluctuations of velocity. These fluctuations make the bioreactive system pulsate: The aerobic zone decreases at times of low velocity and increases at those of high velocity. For the case of diurnal fluctuations, the biomass concentrations cannot follow the hydrological fluctuations and a transition zone containing both aerobic and obligatory denitrifying bacteria is established, whereas a clear separation of the two types of bacteria prevails in the case of seasonal velocity fluctuations. We map the 1-D results to a heterogeneous, two-dimensional domain by means of the mean groundwater age for steady-state flow in both domains. The mapped results are compared to simulation results of spatially explicit, two-dimensional, advective-dispersive-bioreactive transport subject to the same relative fluctuations of velocity as in the one-dimensional model. The agreement between the mapped 1-D and the explicit 2-D results is excellent. We conclude that travel-time models of nonlinear bioreactive transport are adequate in systems of time-periodic flow if the flow direction does not change

  17. Invisible Bridges: Wireless Technology Links Minds over Space and Time (United States)

    Lambert, Lori


    Eight years after Chief Sitting Bull, prophetic chief of the Great Sioux Nation, was assassinated in 1890, Guglielmo Marconi transmitted the first wireless telegraph signals across the Atlantic to England. Although these two events seem unrelated, the names of these two men of vision are linked together today by Marconi's wireless invention. Data,…

  18. Wet periods in northeastern Brazil over the past 210 kyr linked to distant climate anomalies. (United States)

    Wang, Xianfeng; Auler, Augusto S; Edwards, R Lawrence; Cheng, Hai; Cristalli, Patricia S; Smart, Peter L; Richards, David A; Shen, Chuan-Chou


    The tropics are the main source of the atmosphere's sensible and latent heat, and water vapour, and are therefore important for reconstructions of past climate. But long, accurately dated records of southern tropical palaeoclimate, which would allow the establishment of climatic connections to distant regions, have not been available. Here we present a 210,000-year (210-kyr) record of wet periods in tropical northeastern Brazil--a region that is currently semi-arid. The record is obtained from speleothems and travertine deposits that are accurately dated using the U/Th method. We find wet periods that are synchronous with periods of weak East Asian summer monsoons, cold periods in Greenland, Heinrich events in the North Atlantic and periods of decreased river runoff to the Cariaco basin. We infer that the wet periods may be explained with a southward displacement of the Intertropical Convergence Zone. This widespread synchroneity of climate anomalies suggests a relatively rapid global reorganization of the ocean-atmosphere system. We conclude that the wet periods probably affected rainforest distribution, as plant fossils show that forest expansion occurred during these intermittent wet intervals, and opened a forest corridor between the Amazonian and Atlantic rainforests.

  19. Predictability of Landslide Timing From Quasi-Periodic Precursory Earthquakes (United States)

    Bell, Andrew F.


    Accelerating rates of geophysical signals are observed before a range of material failure phenomena. They provide insights into the physical processes controlling failure and the basis for failure forecasts. However, examples of accelerating seismicity before landslides are rare, and their behavior and forecasting potential are largely unknown. Here I use a Bayesian methodology to apply a novel gamma point process model to investigate a sequence of quasiperiodic repeating earthquakes preceding a large landslide at Nuugaatsiaq in Greenland in June 2017. The evolution in earthquake rate is best explained by an inverse power law increase with time toward failure, as predicted by material failure theory. However, the commonly accepted power law exponent value of 1.0 is inconsistent with the data. Instead, the mean posterior value of 0.71 indicates a particularly rapid acceleration toward failure and suggests that only relatively short warning times may be possible for similar landslides in future.

  20. Network Organization Unfolds over Time during Periods of Anxious Anticipation


    McMenamin, Brenton W.; Langeslag, Sandra J.E.; Sirbu, Mihai; Padmala, Srikanth; Pessoa, Luiz


    Entering a state of anxious anticipation triggers widespread changes across large-scale networks in the brain. The temporal aspects of this transition into an anxious state are poorly understood. To address this question, an instructed threat of shock paradigm was used while recording functional MRI in humans to measure how activation and functional connectivity change over time across the salience, executive, and task-negative networks and how they interact with key regions implicated in emo...

  1. [Obesity and complementary feeding time: a period at risk]. (United States)

    Vidailhet, M


    Relation between rapid growth during the first months of life and secondary risk of excessive adiposity is well demonstrated. Many works have indicated a birth feeding effect on weight gain during the first year of life and a protective effect towards later childhood and adult obesity. However all these studies are observational and several works denied this protective effect. Concerning complementary feeding, 3 interventional, randomized, studies achieved between 4 and 6 months of age, showed a good regulation of caloric intake and no weight gain modification due to complementary foods. Most of others studies are observational and don't show any relation between time of introduction of complementary foods and later fat mass. However 3 recent studies indicate, respectively at 7, 10 and 42 years of age, an increased adiposity, suggesting the possibility of a programmed excessive fat gain induced by an early complementary foods introduction. Very few studies have evaluated, besides the time of weaning, the kind, quantity and caloric density of foods used as complements, whereas other recent studies show the importance of appetite differences since the first months of life and the importance of genetic influence on these variations. Others works have emphasized the possible role of an excessive protein intake during the first 2 years of life. So, it appears that it may be necessary to pay attention not only on the date, but also on the kind and quantity of complementary foods, particularly in infants at risk for obesity, because of parental obesity, rapid weight growth or an excessive appetite. Copyright © 2010 Elsevier Masson SAS. All rights reserved.

  2. Enhanced diffusion with abnormal temperature dependence in underdamped space-periodic systems subject to time-periodic driving (United States)

    Marchenko, I. G.; Marchenko, I. I.; Zhiglo, A. V.


    We present a study of the diffusion enhancement of underdamped Brownian particles in a one-dimensional symmetric space-periodic potential due to external symmetric time-periodic driving with zero mean. We show that the diffusivity can be enhanced by many orders of magnitude at an appropriate choice of the driving amplitude and frequency. The diffusivity demonstrates abnormal (decreasing) temperature dependence at the driving amplitudes exceeding a certain value. At any fixed driving frequency Ω normal temperature dependence of the diffusivity is restored at low enough temperatures, T oscillation frequency at the potential minimum, the diffusivity is shown to decrease with Ω according to a power law, with the exponent related to the transient superdiffusion exponent. This behavior is found similar for the cases of sinusoidal in time and piecewise constant periodic ("square") driving.

  3. Biological causal links on physiological and evolutionary time scales. (United States)

    Karmon, Amit; Pilpel, Yitzhak


    Correlation does not imply causation. If two variables, say A and B, are correlated, it could be because A causes B, or that B causes A, or because a third factor affects them both. We suggest that in many cases in biology, the causal link might be bi-directional: A causes B through a fast-acting physiological process, while B causes A through a slowly accumulating evolutionary process. Furthermore, many trained biologists tend to consistently focus at first on the fast-acting direction, and overlook the slower process in the opposite direction. We analyse several examples from modern biology that demonstrate this bias (codon usage optimality and gene expression, gene duplication and genetic dispensability, stem cell division and cancer risk, and the microbiome and host metabolism) and also discuss an example from linguistics. These examples demonstrate mutual effects between the fast physiological processes and the slow evolutionary ones. We believe that building awareness of inference biases among biologists who tend to prefer one causal direction over another could improve scientific reasoning.

  4. A Space-Time Periodic Task Model for Recommendation of Remote Sensing Images

    Directory of Open Access Journals (Sweden)

    Xiuhong Zhang


    Full Text Available With the rapid development of remote sensing technology, the quantity and variety of remote sensing images are growing so quickly that proactive and personalized access to data has become an inevitable trend. One of the active approaches is remote sensing image recommendation, which can offer related image products to users according to their preference. Although multiple studies on remote sensing retrieval and recommendation have been performed, most of these studies model the user profiles only from the perspective of spatial area or image features. In this paper, we propose a spatiotemporal recommendation method for remote sensing data based on the probabilistic latent topic model, which is named the Space-Time Periodic Task model (STPT. User retrieval behaviors of remote sensing images are represented as mixtures of latent tasks, which act as links between users and images. Each task is associated with the joint probability distribution of space, time and image characteristics. Meanwhile, the von Mises distribution is introduced to fit the distribution of tasks over time. Then, we adopt Gibbs sampling to learn the random variables and parameters and present the inference algorithm for our model. Experiments show that the proposed STPT model can improve the capability and efficiency of remote sensing image data services.

  5. Periodic analysis of solar activity and its link with the Arctic oscillation phenomenon

    Energy Technology Data Exchange (ETDEWEB)

    Qu, Weizheng; Li, Chun; Du, Ling; Huang, Fei [Ocean University of China, 14-1' -601, 2117 Jinshui Road, Qingdao 266100 (China); Li, Yanfang, E-mail: [Yantai Institute of Coastal Zone Research Chinese Academy of Sciences (China)


    Based on spectrum analysis, we provide the arithmetic expressions of the quasi 11 yr cycle, 110 yr century cycle of relative sunspot numbers, and quasi 22 yr cycle of solar magnetic field polarity. Based on a comparative analysis of the monthly average geopotential height, geopotential height anomaly, and temperature anomaly of the northern hemisphere at locations with an air pressure of 500 HPa during the positive and negative phases of AO (Arctic Oscillation), one can see that the abnormal warming period in the Arctic region corresponds to the negative phase of AO, while the anomalous cold period corresponds to its positive phase. This shows that the abnormal change in the Arctic region is an important factor in determining the anomalies of AO. In accordance with the analysis performed using the successive filtering method, one can see that the AO phenomenon occurring in January shows a clear quasi 88 yr century cycle and quasi 22 yr decadal cycle, which are closely related to solar activities. The results of our comparative analysis show that there is a close inverse relationship between the solar activities (especially the solar magnetic field index changes) and the changes in the 22 yr cycle of the AO occurring in January, and that the two trends are basically opposite of each other. That is to say, in most cases after the solar magnetic index MI rises from the lowest value, the solar magnetic field turns from north to south, and the high-energy particle flow entering the Earth's magnetosphere increases to heat the polar atmosphere, thus causing the AO to drop from the highest value; after the solar magnetic index MI drops from the highest value, the solar magnetic field turns from south to north, and the solar high-energy particle flow passes through the top of the Earth's magnetosphere rather than entering it to heat the polar atmosphere. Thus the polar temperature drops, causing the AO to rise from the lowest value. In summary, the variance

  6. Natural convection in square enclosure induced by inner circular cylinder with time-periodic pulsating temperature

    KAUST Repository

    Huang, Zhu; Zhang, Wei; Xi, Guang


    The periodic unsteady natural convection flow and heat transfer in a square enclosure containing a concentric circular cylinder is numerically studied. The temperature of the inner circular cylinder fluctuates periodically with time at higher

  7. Third party bargaining and contract terms: a link over time? (United States)

    Brooks, John M; Doucette, William R; Sorofman, Bernard A


    To evaluate whether prior pharmacy bargaining process strategies and pharmacy dependence on third parties affect the bargaining power of pharmacies in price negotiations with third parties. One-time survey. Random sample of 900 independent and small chain pharmacies in nine states: Colorado, Connecticut, Georgia, Kentucky, Minnesota, Oklahoma, Oregon, Pennsylvania, and Wisconsin. Two hundred sixteen of the returned surveys contained sufficient responses for this analysis. Survey data on pharmacy bargaining power and prior pharmacy bargaining strategies, pharmacy dependence, and market characteristics were analyzed using multiple regression in a previously developed and modified provider/third party bargaining model. Pharmacy bargaining power. Pharmacy bargaining power varied across our sample. Pharmacy bargaining power was positively related to whether a pharmacy previously bargained with the third parties, negatively related to prior requests for contract changes, and negatively related to the pharmacy's dependence on third parties in total. Pharmacy bargaining power is related to the bargaining strategies employed by pharmacies during the previous year and the dependence of pharmacies on third party payers in total. With the prevalence of "take-it-or-leave-it" contracts from third parties, prior pharmacy bargaining behavior may affect the initial terms of the contracts that pharmacies are offered.

  8. Finite-Difference Time-Domain Simulation of Light Propagation in 2D Periodic and Quasi-Periodic Photonic Structures

    Directory of Open Access Journals (Sweden)

    N. Dadashzadeh


    Full Text Available Ultra-short pulse is a promising technology for achieving ultra-high data rate transmission which is required to follow the increased demand of data transport over an optical communication system. Therefore, the propagation of such type of pulses and the effects that it may suffer during its transmission through an optical waveguide has received a great deal of attention in the recent years. We provide an overview of recent theoretical developments in a numerical modeling of Maxwell's equations to analyze the propagation of short laser pulses in photonic structures. The process of short light pulse propagation through 2D periodic and quasi-periodic photonic structures is simulated based on Finite-Difference Time-Domain calculations of Maxwell’s equations.

  9. Space Network Time Distribution and Synchronization Protocol Development for Mars Proximity Link (United States)

    Woo, Simon S.; Gao, Jay L.; Mills, David


    Time distribution and synchronization in deep space network are challenging due to long propagation delays, spacecraft movements, and relativistic effects. Further, the Network Time Protocol (NTP) designed for terrestrial networks may not work properly in space. In this work, we consider the time distribution protocol based on time message exchanges similar to Network Time Protocol (NTP). We present the Proximity-1 Space Link Interleaved Time Synchronization (PITS) algorithm that can work with the CCSDS Proximity-1 Space Data Link Protocol. The PITS algorithm provides faster time synchronization via two-way time transfer over proximity links, improves scalability as the number of spacecraft increase, lowers storage space requirement for collecting time samples, and is robust against packet loss and duplication which underlying protocol mechanisms provide.

  10. Structure and dating errors in the geologic time scale and periodicity in mass extinctions (United States)

    Stothers, Richard B.


    Structure in the geologic time scale reflects a partly paleontological origin. As a result, ages of Cenozoic and Mesozoic stage boundaries exhibit a weak 28-Myr periodicity that is similar to the strong 26-Myr periodicity detected in mass extinctions of marine life by Raup and Sepkoski. Radiometric dating errors in the geologic time scale, to which the mass extinctions are stratigraphically tied, do not necessarily lessen the likelihood of a significant periodicity in mass extinctions, but do spread the acceptable values of the period over the range 25-27 Myr for the Harland et al. time scale or 25-30 Myr for the DNAG time scale. If the Odin time scale is adopted, acceptable periods fall between 24 and 33 Myr, but are not robust against dating errors. Some indirect evidence from independently-dated flood-basalt volcanic horizons tends to favor the Odin time scale.

  11. Time-periodic solution of a 2D fourth-order nonlinear parabolic ...

    Indian Academy of Sciences (India)

    appropriate function space for the initial boundary value problem. ... time discretizations which allow much larger time steps than those of a standard implicit– explicit approach. ... set of ω-periodic X-valued measurable functions on R such that.

  12. Smith predictor-based multiple periodic disturbance compensation for long dead-time processes (United States)

    Tan, Fang; Li, Han-Xiong; Shen, Ping


    Many disturbance rejection methods have been proposed for processes with dead-time, while these existing methods may not work well under multiple periodic disturbances. In this paper, a multiple periodic disturbance rejection is proposed under the Smith predictor configuration for processes with long dead-time. One feedback loop is added to compensate periodic disturbance while retaining the advantage of the Smith predictor. With information of the disturbance spectrum, the added feedback loop can remove multiple periodic disturbances effectively. The robust stability can be easily maintained through the rigorous analysis. Finally, simulation examples demonstrate the effectiveness and robustness of the proposed method for processes with long dead-time.

  13. Software Modules for the Proximity-1 Space Link Interleaved Time Synchronization (PITS) Protocol (United States)

    Woo, Simon S.; Veregge, John R.; Gao, Jay L.; Clare, Loren P.; Mills, David


    The Proximity-1 Space Link Interleaved Time Synchronization (PITS) protocol provides time distribution and synchronization services for space systems. A software prototype implementation of the PITS algorithm has been developed that also provides the test harness to evaluate the key functionalities of PITS with simulated data source and sink. PITS integrates time synchronization functionality into the link layer of the CCSDS Proximity-1 Space Link Protocol. The software prototype implements the network packet format, data structures, and transmit- and receive-timestamp function for a time server and a client. The software also simulates the transmit and receive-time stamp exchanges via UDP (User Datagram Protocol) socket between a time server and a time client, and produces relative time offsets and delay estimates.

  14. A deterministic, gigabit serial timing, synchronization and data link for the RHIC LLRF

    International Nuclear Information System (INIS)

    Hayes, T.; Smith, K.S.; Severino, F.


    A critical capability of the new RHIC low level rf (LLRF) system is the ability to synchronize signals across multiple locations. The 'Update Link' provides this functionality. The 'Update Link' is a deterministic serial data link based on the Xilinx RocketIO protocol that is broadcast over fiber optic cable at 1 gigabit per second (Gbps). The link provides timing events and data packets as well as time stamp information for synchronizing diagnostic data from multiple sources. The new RHIC LLRF was designed to be a flexible, modular system. The system is constructed of numerous independent RF Controller chassis. To provide synchronization among all of these chassis, the Update Link system was designed. The Update Link system provides a low latency, deterministic data path to broadcast information to all receivers in the system. The Update Link system is based on a central hub, the Update Link Master (ULM), which generates the data stream that is distributed via fiber optic links. Downstream chassis have non-deterministic connections back to the ULM that allow any chassis to provide data that is broadcast globally.

  15. 12 CFR 516.10 - How does OTS compute time periods under this part? (United States)


    ... 12 Banks and Banking 5 2010-01-01 2010-01-01 false How does OTS compute time periods under this part? 516.10 Section 516.10 Banks and Banking OFFICE OF THRIFT SUPERVISION, DEPARTMENT OF THE TREASURY APPLICATION PROCESSING PROCEDURES § 516.10 How does OTS compute time periods under this part? In computing...

  16. 19 CFR 351.524 - Allocation of benefit to a particular time period. (United States)


    ... 19 Customs Duties 3 2010-04-01 2010-04-01 false Allocation of benefit to a particular time period. 351.524 Section 351.524 Customs Duties INTERNATIONAL TRADE ADMINISTRATION, DEPARTMENT OF COMMERCE... Allocation of benefit to a particular time period. Unless otherwise specified in §§ 351.504-351.523, the...

  17. 17 CFR 260.7a-24 - Words relating to periods of time in the past. (United States)


    ... 17 Commodity and Securities Exchanges 3 2010-04-01 2010-04-01 false Words relating to periods of time in the past. 260.7a-24 Section 260.7a-24 Commodity and Securities Exchanges SECURITIES AND... Requirements As to Contents § 260.7a-24 Words relating to periods of time in the past. Unless the context...

  18. Data-linked pilot reply time on controller workload and communication in a simulated terminal option (United States)


    This report describes an analysis of air traffic control communication and workload in a simulated terminal radar approach : control environment. The objective of this study was to investigate how pilot-to-controller data-link acknowledgment time : m...

  19. Modal Vibration Control in Periodic Time-Varying Structures with Focus on Rotor Blade Systems

    DEFF Research Database (Denmark)

    Christensen, Rene Hardam; Santos, Ilmar


    of active modal controllers. The main aim is to reduce vibrations in periodic time-varying structures. Special emphasis is given to vibration control of coupled bladed rotor systems. A state feedback modal control law is developed based on modal analysis in periodic time-varying structures. The first step...... in the procedure is a transformation of the model into a time-invariant modal form by applying the modal matrices, which are also periodic time-variant. Due to coupled rotor and blade motions complex vibration modes occur in the modal transformed state space model. This implies that the modal transformed model...

  20. Scattering analysis of periodic structures using finite-difference time-domain

    CERN Document Server

    ElMahgoub, Khaled; Elsherbeni, Atef Z


    Periodic structures are of great importance in electromagnetics due to their wide range of applications such as frequency selective surfaces (FSS), electromagnetic band gap (EBG) structures, periodic absorbers, meta-materials, and many others. The aim of this book is to develop efficient computational algorithms to analyze the scattering properties of various electromagnetic periodic structures using the finite-difference time-domain periodic boundary condition (FDTD/PBC) method. A new FDTD/PBC-based algorithm is introduced to analyze general skewed grid periodic structures while another algor

  1. The existence and global attractivity of almost periodic sequence solution of discrete-time neural networks

    International Nuclear Information System (INIS)

    Huang Zhenkun; Wang Xinghua; Gao Feng


    In this Letter, we discuss discrete-time analogue of a continuous-time cellular neural network. Sufficient conditions are obtained for the existence of a unique almost periodic sequence solution which is globally attractive. Our results demonstrate dynamics of the formulated discrete-time analogue as mathematical models for the continuous-time cellular neural network in almost periodic case. Finally, a computer simulation illustrates the suitability of our discrete-time analogue as numerical algorithms in simulating the continuous-time cellular neural network conveniently

  2. Period, epoch, and prediction errors of ephemerides from continuous sets of timing measurements (United States)

    Deeg, H. J.


    Space missions such as Kepler and CoRoT have led to large numbers of eclipse or transit measurements in nearly continuous time series. This paper shows how to obtain the period error in such measurements from a basic linear least-squares fit, and how to correctly derive the timing error in the prediction of future transit or eclipse events. Assuming strict periodicity, a formula for the period error of these time series is derived, σP = σT (12 / (N3-N))1 / 2, where σP is the period error, σT the timing error of a single measurement, and N the number of measurements. Compared to the iterative method for period error estimation by Mighell & Plavchan (2013), this much simpler formula leads to smaller period errors, whose correctness has been verified through simulations. For the prediction of times of future periodic events, usual linear ephemeris were epoch errors are quoted for the first time measurement, are prone to an overestimation of the error of that prediction. This may be avoided by a correction for the duration of the time series. An alternative is the derivation of ephemerides whose reference epoch and epoch error are given for the centre of the time series. For long continuous or near-continuous time series whose acquisition is completed, such central epochs should be the preferred way for the quotation of linear ephemerides. While this work was motivated from the analysis of eclipse timing measures in space-based light curves, it should be applicable to any other problem with an uninterrupted sequence of discrete timings for which the determination of a zero point, of a constant period and of the associated errors is needed.

  3. Switched periodic systems in discrete time: stability and input-output norms (United States)

    Bolzern, Paolo; Colaneri, Patrizio


    This paper deals with the analysis of stability and the characterisation of input-output norms for discrete-time periodic switched linear systems. Such systems consist of a network of time-periodic linear subsystems sharing the same state vector and an exogenous switching signal that triggers the jumps between the subsystems. The overall system exhibits a complex dynamic behaviour due to the interplay between the time periodicity of the subsystem parameters and the switching signal. Both arbitrary switching signals and signals satisfying a dwell-time constraint are considered. Linear matrix inequality conditions for stability and guaranteed H2 and H∞ performances are provided. The results heavily rely on the merge of the theory of linear periodic systems and recent developments on switched linear time-invariant systems.

  4. Decomposing the effects of time on the social acceptability of biotechnology using age-period-cohort-country models. (United States)

    Rousselière, Damien; Rousselière, Samira


    The study of European attitudes toward biotechnologies underlines a situation that is relatively contrasting in Europe. However, as different effects of time can influence the social attitudes (a life-cycle effect, a generational effect, and an exogenous temporal effect potentially affecting the entire population), an appropriate methodology should be used. To this end, age-period-cohort-country models have thus been estimated based on Eurobarometer data from 1991 onward. Applied to different data subsets, these models give similar results underlining the importance of the life-cycle effects as well as the heterogeneity of the link between political affiliation and biotechnologies attitudes across the European countries.

  5. 46 CFR 167.60-5 - Period of time for which valid. (United States)


    ... SCHOOL SHIPS Certificates of Inspection § 167.60-5 Period of time for which valid. A certificate of inspection for any period less than one year shall not be issued, but nothing herein shall be construed as preventing the revocation or suspension of a certificate of inspection in case such process is authorized by...

  6. Positive Almost Periodic Solutions for a Time-Varying Fishing Model with Delay

    Directory of Open Access Journals (Sweden)

    Xia Li


    Full Text Available This paper is concerned with a time-varying fishing model with delay. By means of the continuation theorem of coincidence degree theory, we prove that it has at least one positive almost periodic solution.

  7. Stability and periodicity of solutions for delay dynamic systems on time scales

    Directory of Open Access Journals (Sweden)

    Zhi-Qiang Zhu


    Full Text Available This article concerns the stability and periodicity of solutions to the delay dynamic system $$ x^{\\triangle}(t=A(t x(t + F(t, x(t, x(g(t+C(t $$ on a time scale. By the inequality technique for vectors, we obtain some stability criteria for the above system. Then, by using the Horn fixed point theorem, we present some conditions under which our system is asymptotically periodic and its periodic solution is unique. In particular, the periodic solution is positive under proper assumptions.

  8. Real time data acquisition of a countrywide commercial microwave link network (United States)

    Chwala, Christian; Keis, Felix; Kunstmann, Harald


    Research in recent years has shown that data from commercial microwave link networks can provide very valuable precipitation information. Since these networks comprise the backbone of the cell phone network, they provide countrywide coverage. However acquiring the necessary data from the network operators is still difficult. Data is usually made available for researchers with a large time delay and often at irregular basis. This of course hinders the exploitation of commercial microwave link data in operational applications like QPE forecasts running at national meteorological services. To overcome this, we have developed a custom software in joint cooperation with our industry partner Ericsson. The software is installed on a dedicated server at Ericsson and is capable of acquiring data from the countrywide microwave link network in Germany. In its current first operational testing phase, data from several hundred microwave links in southern Germany is recorded. All data is instantaneously sent to our server where it is stored and organized in an emerging database. Time resolution for the Ericsson data is one minute. The custom acquisition software, however, is capable of processing higher sampling rates. Additionally we acquire and manage 1 Hz data from four microwave links operated by the skiing resort in Garmisch-Partenkirchen. We will present the concept of the data acquisition and show details of the custom-built software. Additionally we will showcase the accessibility and basic processing of real time microwave link data via our database web frontend.

  9. White Rabbit Precision Time Protocol on Long-Distance Fiber Links. (United States)

    Dierikx, Erik F; Wallin, Anders E; Fordell, Thomas; Myyry, Jani; Koponen, Petri; Merimaa, Mikko; Pinkert, Tjeerd J; Koelemeij, Jeroen C J; Peek, Henk Z; Smets, Rob


    The application of White Rabbit precision time protocol (WR-PTP) in long-distance optical fiber links has been investigated. WR-PTP is an implementation of PTP in synchronous Ethernet optical fiber networks, originally intended for synchronization of equipment within a range of 10 km. This paper discusses the results and limitations of two implementations of WR-PTP in the existing communication fiber networks. A 950-km WR-PTP link was realized using unidirectional paths in a fiber pair between Espoo and Kajaani, Finland. The time transfer on this link was compared (after initial calibration) against a clock comparison by GPS precise point positioning (PPP). The agreement between the two methods remained within [Formula: see text] over three months of measurements. Another WR-PTP implementation was realized between Delft and Amsterdam, the Netherlands, by cascading two links of 137 km each. In this case, the WR links were realized as bidirectional paths in single fibers. The measured time offset between the starting and end points of the link was within 5 ns with an uncertainty of 8 ns, mainly due to the estimated delay asymmetry caused by chromatic dispersion.

  10. Wuchereria bancrofti in Tanzania: microfilarial periodicity and effect of blood sampling time on microfilarial intensities

    DEFF Research Database (Denmark)

    Simonsen, Poul Erik; Niemann, L.; Meyrowitsch, Dan Wolf


    The circadian periodicity of Wuchereria bancrofti microfilarial (mf) intensities in peripheral blood was analysed in a group of infected individuals from an endemic community in north-eastern Tanzania. The mf density was quantified at two-hourly intervals for 24 hours. A clear nocturnal periodic...... of blood sampling before peak time is discussed, and the importance of taking sampling time into consideration when analysing data from epidemiological studies is emphasized. A simple method is devised which can be used to adjust for the influence of time on mf intensities, in studies where accurate...... information on mf intensities is necessary, and where it is impossible to obtain all samples at peak time....

  11. Existence of time-periodic weak solutions to the stochastic Navier-Stokes equations around a moving body

    International Nuclear Information System (INIS)

    Chen, Feng; Han, Yuecai


    The existence of time-periodic stochastic motions of an incompressible fluid is obtained. Here the fluid is subject to a time-periodic body force and an additional time-periodic stochastic force that is produced by a rigid body moves periodically stochastically with the same period in the fluid

  12. Existence of time-periodic weak solutions to the stochastic Navier-Stokes equations around a moving body

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Feng, E-mail:, E-mail:; Han, Yuecai, E-mail:, E-mail: [School of Mathematics, Jilin University, Changchun 130012 (China)


    The existence of time-periodic stochastic motions of an incompressible fluid is obtained. Here the fluid is subject to a time-periodic body force and an additional time-periodic stochastic force that is produced by a rigid body moves periodically stochastically with the same period in the fluid.

  13. Occupant Time Period of Thermal Adaption to Change of Outdoor Air Temperature in Naturally Ventilated Buildings

    DEFF Research Database (Denmark)

    liu, weiwei; Wargocki, Pawel; Xiong, Jing


    The present work proposed a method to determine time period of thermal adaption of occupants in naturally ventilated building, based on the relationship between their neutral temperatures and running mean outdoor air temperature. Based on the data of the field investigation, the subjects’ time...

  14. Investigation of unstable periodic space-time states in distributed active system with supercritical current

    International Nuclear Information System (INIS)

    Koronovskij, A.A.; Rempen, I.S.; Khramov, A.E.


    The set of the unstable periodic space-time states, characterizing the chaotic space-time dynamics of the electron beam with the supercritical current in the Pierce diode is discussed. The Lyapunov indicators of the revealed instable space-time states of the chaotic dynamics of the distributed self-excited system are calculated. It is shown that change in the set of the unstable periodic states in dependence on the Pierce parameter is determined by change in the various orbits stability, which is demonstrated by the values of senior Lyapunov unstable state index [ru

  15. Sensitivity of Hurst parameter estimation to periodic signals in time series and filtering approaches (United States)

    Marković, D.; Koch, M.


    The influence of the periodic signals in time series on the Hurst parameter estimate is investigated with temporal, spectral and time-scale methods. The Hurst parameter estimates of the simulated periodic time series with a white noise background show a high sensitivity on the signal to noise ratio and for some methods, also on the data length used. The analysis is then carried on to the investigation of extreme monthly river flows of the Elbe River (Dresden) and of the Rhine River (Kaub). Effects of removing the periodic components employing different filtering approaches are discussed and it is shown that such procedures are a prerequisite for an unbiased estimation of H. In summary, our results imply that the first step in a time series long-correlation study should be the separation of the deterministic components from the stochastic ones. Otherwise wrong conclusions concerning possible memory effects may be drawn.

  16. Life time calculations for LCF loading combined with tensional hold periods

    International Nuclear Information System (INIS)

    Bocek, M.; Armas, A.; Piel, D.


    The life time in high amplitude strain cycling with tensional hold periods is analysed presuming that creep failure damage is life determining. The life fraction rule (LFR) is used to calculate the life time consumpted during the dwell period in strain controlled tests as well as during tensional hold time stress cycles. It follows from the present investigation that stress relaxation occurring during the strain hold periods plays the dominant influence upon the relationship between life and dwell time. For strong stress relaxation (e.g. high temperature) less damage is accumulated as compared to suppressed relaxation (low temperature). The damage in stress relaxation is calculated by means of the LFR and the results are compared to experiments conducted on Zircaloy-4 and the austenitic stainless stell Type AISI 304. From the very good agreement between both it is concluded that under the loading conditions considered, creep failure damage is the main life determining damage contribution. (orig.)

  17. Depression in the US population during the time periods surrounding the great recession. (United States)

    Mehta, Kaushal; Kramer, Holly; Durazo-Arvizu, Ramon; Cao, Guichan; Tong, Liping; Rao, Murali


    To determine whether the time periods surrounding the 2008 US economic downturn were accompanied by an increase in prevalence of depression in the US adult population. We used data from the 24,182 adults aged ≥ 18 years who participated in the National Health and Nutrition Examination Survey during 2005-2012. A cross-sectional analysis was performed at each time period to determine prevalence of major and other depression as assessed by standardized questionnaires based on 9 criteria for major depressive episodes defined by DSM-IV. The demographic characteristics of the US population were similar across time periods except for the percentage of adults living in poverty, which increased from 26.43% during 2005-2006 to 33.46% during 2011-2012. The prevalence of major depression increased from 2.33% (95% CI, 1.64%-3.01%) during 2005-2006 to 3.49% (95% CI, 2.84%-4.03%) in 2009-2010 to 3.79% (95% CI, 3.01%-4.57%) in 2011-2012. Prevalence of other depression increased from 4.10% (95% CI, 3.37%-4.88%) in 2005-2006 to 4.79% (95% CI, 4.10%-5.44%) in the 2009-2010 period but then declined to 3.68% (95% CI, 2.84%-4.48%) in the 2011-2012 time period (P = .4). After adjustment for the distribution of age, sex, race/ethnicity, education, insurance status, and poverty status in the US adult noninstitutionalized population, each 2-year period after the 2005-2006 time period was associated with a 0.4% increase in major depression prevalence (P depression prevalence were noted by time period (P = .6). The time periods surrounding the recent economic recession were accompanied by a significant and sustained increase in major depression prevalence in the US population. It is plausible that the recession, given its strong, persistent, and negative effects on employment, job and housing security, and stock investments, contributed to the sustained increase in prevalence of major depression in the US population, but other factors associated with the recession time period could have

  18. Almost Periodic Solution for Memristive Neural Networks with Time-Varying Delays

    Directory of Open Access Journals (Sweden)

    Huaiqin Wu


    Full Text Available This paper is concerned with the dynamical stability analysis for almost periodic solution of memristive neural networks with time-varying delays. Under the framework of Filippov solutions, by applying the inequality analysis techniques, the existence and asymptotically almost periodic behavior of solutions are discussed. Based on the differential inclusions theory and Lyapunov functional approach, the stability issues of almost periodic solution are investigated, and a sufficient condition for the existence, uniqueness, and global exponential stability of the almost periodic solution is established. Moreover, as a special case, the condition which ensures the global exponential stability of a unique periodic solution is also presented for the considered memristive neural networks. Two examples are given to illustrate the validity of the theoretical results.

  19. The Sensitivity of Income Polarization - Time, length of accounting periods, equivalence scales, and income definitions

    DEFF Research Database (Denmark)

    Azhar, Hussain

    This study looks at polarization and its components’ sensitivity to assumptions about equivalence scales, income definition, ethical income distribution parameters, and the income accounting period. A representative sample of Danish individual incomes from 1984 to 2002 is utilised. Results show...... that polarization has increased over time, regardless of the applied measure, when the last part of the period is compared to the first part of the period. Primary causes being increased inequality (alienation) and faster income growth among high incomes relative to those in the middle of the distribution....... Increasing the accounting period confirms the reduction in inequality found for shorter periods, but polarization is virtually unchanged, because income group identification increases. Applying different equivalence scales does not change polarization ranking for different years, but identification ranks...

  20. Finding hidden periodic signals in time series - an application to stock prices (United States)

    O'Shea, Michael


    Data in the form of time series appear in many areas of science. In cases where the periodicity is apparent and the only other contribution to the time series is stochastic in origin, the data can be `folded' to improve signal to noise and this has been done for light curves of variable stars with the folding resulting in a cleaner light curve signal. Stock index prices versus time are classic examples of time series. Repeating patterns have been claimed by many workers and include unusually large returns on small-cap stocks during the month of January, and small returns on the Dow Jones Industrial average (DJIA) in the months June through September compared to the rest of the year. Such observations imply that these prices have a periodic component. We investigate this for the DJIA. If such a component exists it is hidden in a large non-periodic variation and a large stochastic variation. We show how to extract this periodic component and for the first time reveal its yearly (averaged) shape. This periodic component leads directly to the `Sell in May and buy at Halloween' adage. We also drill down and show that this yearly variation emerges from approximately half of the underlying stocks making up the DJIA index.

  1. Boundedness and almost Periodicity in Time of Solutions of Evolutionary Variational Inequalities (United States)

    Pankov, A. A.


    In this paper existence theorems are obtained for the solutions of abstract parabolic variational inequalities, which are bounded with respect to time (in the Stepanov and L^\\infty norms). The regularity and almost periodicity properties of such solutions are studied. Theorems are also established concerning their solvability in spaces of Besicovitch almost periodic functions. The majority of the results are obtained without any compactness assumptions. Bibliography: 30 titles.

  2. Practitioners' Perceptions of the Soccer Extra-Time Period: Implications for Future Research


    Harper, Liam D.; Fothergill, Melissa; West, Daniel J.; Stevenson, Emma; Russell, Mark


    Qualitative research investigating soccer practitioners’ perceptions can allow researchers to create practical research investigations. The extra-time period of soccer is understudied compared to other areas of soccer research. Using an open-ended online survey containing eleven main and nine sub questions, we gathered the perceptions of extra-time from 46 soccer practitioners, all working for different professional soccer clubs. Questions related to current practices, views on extra-time reg...

  3. Rank One Strange Attractors in Periodically Kicked Predator-Prey System with Time-Delay (United States)

    Yang, Wenjie; Lin, Yiping; Dai, Yunxian; Zhao, Huitao


    This paper is devoted to the study of the problem of rank one strange attractor in a periodically kicked predator-prey system with time-delay. Our discussion is based on the theory of rank one maps formulated by Wang and Young. Firstly, we develop the rank one chaotic theory to delayed systems. It is shown that strange attractors occur when the delayed system undergoes a Hopf bifurcation and encounters an external periodic force. Then we use the theory to the periodically kicked predator-prey system with delay, deriving the conditions for Hopf bifurcation and rank one chaos along with the results of numerical simulations.

  4. Detecting method for crude oil price fluctuation mechanism under different periodic time series

    International Nuclear Information System (INIS)

    Gao, Xiangyun; Fang, Wei; An, Feng; Wang, Yue


    Highlights: • We proposed the concept of autoregressive modes to indicate the fluctuation patterns. • We constructed transmission networks for studying the fluctuation mechanism. • There are different fluctuation mechanism under different periodic time series. • Only a few types of autoregressive modes control the fluctuations in crude oil price. • There are cluster effects during the fluctuation mechanism of autoregressive modes. - Abstract: Current existing literatures can characterize the long-term fluctuation of crude oil price time series, however, it is difficult to detect the fluctuation mechanism specifically under short term. Because each fluctuation pattern for one short period contained in a long-term crude oil price time series have dynamic characteristics of diversity; in other words, there exhibit various fluctuation patterns in different short periods and transmit to each other, which reflects the reputedly complicate and chaotic oil market. Thus, we proposed an incorporated method to detect the fluctuation mechanism, which is the evolution of the different fluctuation patterns over time from the complex network perspective. We divided crude oil price time series into segments using sliding time windows, and defined autoregressive modes based on regression models to indicate the fluctuation patterns of each segment. Hence, the transmissions between different types of autoregressive modes over time form a transmission network that contains rich dynamic information. We then capture transmission characteristics of autoregressive modes under different periodic time series through the structure features of the transmission networks. The results indicate that there are various autoregressive modes with significantly different statistical characteristics under different periodic time series. However, only a few types of autoregressive modes and transmission patterns play a major role in the fluctuation mechanism of the crude oil price, and these

  5. Socioecological factors are linked to changes in prevalence of contempt over time. (United States)

    Varnum, Michael E W; Grossmann, Igor


    Gervais & Fessler argue that the perceived legitimacy of contempt has declined over time in the United States, citing evidence of a decrease in the frequency of its use in the American English corpus. We argue that this decline in contempt, as reflected in cultural products, is linked to shifts in key socioecological features previously associated with other forms of cultural change.

  6. White Rabbit Precision Time Protocol on Long-Distance Fiber Links

    NARCIS (Netherlands)

    Dierikx, E.F.; Dierikx, A.E.; Fordell, T.; Myyry, J.; Koponen, P.; Merimaa, M.; Pinkert, T.J.; Koelemeij, J.C.J.; Peek, H.Z.; Smets, R.


    The application of White Rabbit precision time protocol (WR-PTP) in long-distance optical fiber links has been investigated. WR-PTP is an implementation of PTP in synchronous Ethernet optical fiber networks, originally intended for synchronization of equipment within a range of 10 km. This paper

  7. The AMIDA automatic content linking device: Just-in-time document retrieval in meetings

    NARCIS (Netherlands)

    Popescu-Belis, A.; Boertjes, E.M.; Kilgour, J.; Poller, P.; Castronovo, S.; Wilson, T.; Jaimes, A.; Carletta, J.


    The AMIDA Automatic Content Linking Device (ACLD) is a just-in-time document retrieval system for meeting environments. The ACLD listens to a meeting and displays information about the documents from the group's history that are most relevant to what is being said. Participants can view an outline

  8. Attention Biases to Threat Link Behavioral Inhibition to Social Withdrawal over Time in Very Young Children (United States)

    Perez-Edgar, Koraly; Reeb-Sutherland, Bethany C.; McDermott, Jennifer Martin; White, Lauren K.; Henderson, Heather A.; Degnan, Kathryn A.; Hane, Amie A.; Pine, Daniel S.; Fox, Nathan A.


    Behaviorally inhibited children display a temperamental profile characterized by social withdrawal and anxious behaviors. Previous research, focused largely on adolescents, suggests that attention biases to threat may sustain high levels of behavioral inhibition (BI) over time, helping link early temperament to social outcomes. However, no prior…

  9. Exact dynamics of a one dimensional Bose gas in a periodic time-dependent harmonic trap (United States)

    Scopa, Stefano; Unterberger, Jéremie; Karevski, Dragi


    We study the unitary dynamics of a 1D gas of hard-core bosons trapped into a harmonic potential which varies periodically in time with frequency . Such periodic systems can be classified into orbits of different monodromies corresponding to two different physical situations, namely the case in which the bosonic cloud remains stable during the time-evolution and the case where it turns out to be unstable. In the present work we derive in the large particle number limit exact results for the stroboscopic evolution of the energy and particle densities in both physical situations.

  10. A Time-Delayed Mathematical Model for Tumor Growth with the Effect of a Periodic Therapy. (United States)

    Xu, Shihe; Wei, Xiangqing; Zhang, Fangwei


    A time-delayed mathematical model for tumor growth with the effect of periodic therapy is studied. The establishment of the model is based on the reaction-diffusion dynamics and mass conservation law and is considered with a time delay in cell proliferation process. Sufficient conditions for the global stability of tumor free equilibrium are given. We also prove that if external concentration of nutrients is large the tumor will not disappear and the conditions under which there exist periodic solutions to the model are also determined. Results are illustrated by computer simulations.

  11. A Time-Delayed Mathematical Model for Tumor Growth with the Effect of a Periodic Therapy

    Directory of Open Access Journals (Sweden)

    Shihe Xu


    Full Text Available A time-delayed mathematical model for tumor growth with the effect of periodic therapy is studied. The establishment of the model is based on the reaction-diffusion dynamics and mass conservation law and is considered with a time delay in cell proliferation process. Sufficient conditions for the global stability of tumor free equilibrium are given. We also prove that if external concentration of nutrients is large the tumor will not disappear and the conditions under which there exist periodic solutions to the model are also determined. Results are illustrated by computer simulations.

  12. Periodic review inventory policy for non-instantaneous deteriorating items with time dependent deterioration rate

    Directory of Open Access Journals (Sweden)

    Anwesha Samanta


    Full Text Available The paper studies a periodic review inventory model with no shortages and different demand rates during pre- and post- deterioration periods . Deterioration of units start after a fixed time interval, and the deterioration rate is time dependent. The model determines the optimal reorder interval and the optimal order quantity so as to minimize the total cost per unit length of an inventory cycle. An extension of the model to include price discount has been further considered. Numerical examples are presented to illustrate the model and a sensitivity analysis is also reported.

  13. Teleducation : Linking Continents Across Time and Space Through Live, Real-Time Interactive Classes (United States)

    Macko, S. A.; Szuba, T.; Swap, R.; Annegarn, H.; Marjanovic, B.; Vieira, F.; Brito, R.


    International education is a natural extension of global economies, global environmental concerns, and global science. While faculty and student exchanges between geographic areas permit for educational experiences and cultural exchanges for the privileged few, distance learning offers opportunities for educational exchanges under any circumstance where time, expense, or location otherwise inhibit offering or taking a particular course of study. However, there are severe pedagogical limitations to traditional Web-based courses that suffer from a lack of personalized, spontaneous exchange between instructor and student. The technology to establish a real time, interactive teleducation program exists, but to our knowledge is relatively untested in a science classroom situation, especially internationally over great distances. In a project to evaluate this type of linkage, we offered a real-time, interactive class at three separate universities, which communicated instantaneously across an ocean at a distance of greater than 8,000 miles and seven time zones. The course, 'Seminar on the Ecology of African Savannas', consisted of a series of 11 lectures originating in either Mozambique (University of Eduardo Mondlane), South Africa (University of the Witwatersrand) or the United States (University of Virginia). We combined ISDN, internet and satellite linkages to facilitate the lectures and real time discussions between instructors and approximately 200 university students in the three countries. Although numerous technical, logistical, and pedagogical issues - both expected and unexpected - arose throughout the pilot year, the project can be viewed as overwhelmingly successful and certainly serves as proof-of-concept for future initiatives, both internationally and locally. This review of our experience will help to prepare other students, faculty, and institutions interested in establishing or developing international education initiatives

  14. The Improved Adaptive Silence Period Algorithm over Time-Variant Channels in the Cognitive Radio System

    Directory of Open Access Journals (Sweden)

    Jingbo Zhang


    Full Text Available In the field of cognitive radio spectrum sensing, the adaptive silence period management mechanism (ASPM has improved the problem of the low time-resource utilization rate of the traditional silence period management mechanism (TSPM. However, in the case of the low signal-to-noise ratio (SNR, the ASPM algorithm will increase the probability of missed detection for the primary user (PU. Focusing on this problem, this paper proposes an improved adaptive silence period management (IA-SPM algorithm which can adaptively adjust the sensing parameters of the current period in combination with the feedback information from the data communication with the sensing results of the previous period. The feedback information in the channel is achieved with frequency resources rather than time resources in order to adapt to the parameter change in the time-varying channel. The Monte Carlo simulation results show that the detection probability of the IA-SPM is 10–15% higher than that of the ASPM under low SNR conditions.

  15. Monostable traveling waves for a time-periodic and delayed nonlocal reaction-diffusion equation (United States)

    Li, Panxiao; Wu, Shi-Liang


    This paper is concerned with a time-periodic and delayed nonlocal reaction-diffusion population model with monostable nonlinearity. Under quasi-monotone or non-quasi-monotone assumptions, it is known that there exists a critical wave speed c_*>0 such that a periodic traveling wave exists if and only if the wave speed is above c_*. In this paper, we first prove the uniqueness of non-critical periodic traveling waves regardless of whether the model is quasi-monotone or not. Further, in the quasi-monotone case, we establish the exponential stability of non-critical periodic traveling fronts. Finally, we illustrate the main results by discussing two types of death and birth functions arising from population biology.

  16. Money Now, Money Later: Linking Time Discounting and Criminal Convictions in the Cambridge Study in Delinquent Development. (United States)

    Piquero, Alex R; Farrington, David P; Jennings, Wesley G


    Two prominent criminological theories offer time discounting, or the preference for an immediate reward over a later one, as a central part of understanding involvement in criminal activity. Yet, there exist only a few studies investigating this issue, and they are limited in a few respects. The current study extends prior work in this area by using multiple measures of time discounting collected at three different periods of the life course to examine the link to criminal offending into late middle adulthood in the Cambridge Study in Delinquent Development. Results show that greater time discounting is positively related to a higher number of criminal convictions by late middle adulthood, and this effect remains after controlling for early life-course individual and environmental risk in a multivariate framework. Study limitations and implications are also discussed.

  17. Manifold-splitting regularization, self-linking, twisting, writhing numbers of space-time ribbons

    International Nuclear Information System (INIS)

    Tze, C.H.


    The authors present an alternative formulation of Polyakov's regularization of Gauss' integral formula for a single closed Feynman path. A key element in his proof of the D = 3 fermi-bose transmutations induced by topological gauge fields, this regularization is linked here with the existence and properties of a nontrivial topological invariant for a closed space ribbon. This self-linking coefficient, an integer, is the sum of two differential characteristics of the ribbon, its twisting and writhing numbers. These invariants form the basis for a physical interpretation of our regularization. Their connection to Polyakov's spinorization is discussed. The authors further generalize their construction to the self-linking, twisting and writhing of higher dimensional d = eta(odd) submanifolds in D = (2eta + 1) space-time

  18. A Gaussian Process Based Online Change Detection Algorithm for Monitoring Periodic Time Series

    Energy Technology Data Exchange (ETDEWEB)

    Chandola, Varun [ORNL; Vatsavai, Raju [ORNL


    Online time series change detection is a critical component of many monitoring systems, such as space and air-borne remote sensing instruments, cardiac monitors, and network traffic profilers, which continuously analyze observations recorded by sensors. Data collected by such sensors typically has a periodic (seasonal) component. Most existing time series change detection methods are not directly applicable to handle such data, either because they are not designed to handle periodic time series or because they cannot operate in an online mode. We propose an online change detection algorithm which can handle periodic time series. The algorithm uses a Gaussian process based non-parametric time series prediction model and monitors the difference between the predictions and actual observations within a statistically principled control chart framework to identify changes. A key challenge in using Gaussian process in an online mode is the need to solve a large system of equations involving the associated covariance matrix which grows with every time step. The proposed algorithm exploits the special structure of the covariance matrix and can analyze a time series of length T in O(T^2) time while maintaining a O(T) memory footprint, compared to O(T^4) time and O(T^2) memory requirement of standard matrix manipulation methods. We experimentally demonstrate the superiority of the proposed algorithm over several existing time series change detection algorithms on a set of synthetic and real time series. Finally, we illustrate the effectiveness of the proposed algorithm for identifying land use land cover changes using Normalized Difference Vegetation Index (NDVI) data collected for an agricultural region in Iowa state, USA. Our algorithm is able to detect different types of changes in a NDVI validation data set (with ~80% accuracy) which occur due to crop type changes as well as disruptive changes (e.g., natural disasters).

  19. Practitioners' Perceptions of the Soccer Extra-Time Period: Implications for Future Research.

    Directory of Open Access Journals (Sweden)

    Liam D Harper

    Full Text Available Qualitative research investigating soccer practitioners' perceptions can allow researchers to create practical research investigations. The extra-time period of soccer is understudied compared to other areas of soccer research. Using an open-ended online survey containing eleven main and nine sub questions, we gathered the perceptions of extra-time from 46 soccer practitioners, all working for different professional soccer clubs. Questions related to current practices, views on extra-time regulations, and ideas for future research. Using inductive content analysis, the following general dimensions were identified: 'importance of extra-time', 'rule changes', 'efficacy of extra-time hydro-nutritional provision', 'nutritional timing', 'future research directions', 'preparatory modulations' and 'recovery'. The majority of practitioners (63% either agreed or strongly agreed that extra-time is an important period for determining success in knockout football match-play. When asked if a fourth substitution should be permitted in extra-time, 67% agreed. The use of hydro-nutritional strategies prior to extra-time was predominately considered important or very important. However; only 41% of practitioners felt that it was the most important time point for the use of nutritional products. A similar number of practitioners account (50% and do not (50% account for the potential of extra-time when training and preparing players and 89% of practitioners stated that extra-time influences recovery practices following matches. In the five minute break prior to extra-time, the following practices (in order of priority were advocated to players: hydration, energy provision, massage, and tactical preparations. Additionally, 87% of practitioners advocate a particular nutritional supplementation strategy prior to extra-time. In order of importance, practitioners see the following as future research areas: nutritional interventions, fatigue responses, acute injury risk

  20. Practitioners' Perceptions of the Soccer Extra-Time Period: Implications for Future Research. (United States)

    Harper, Liam D; Fothergill, Melissa; West, Daniel J; Stevenson, Emma; Russell, Mark


    Qualitative research investigating soccer practitioners' perceptions can allow researchers to create practical research investigations. The extra-time period of soccer is understudied compared to other areas of soccer research. Using an open-ended online survey containing eleven main and nine sub questions, we gathered the perceptions of extra-time from 46 soccer practitioners, all working for different professional soccer clubs. Questions related to current practices, views on extra-time regulations, and ideas for future research. Using inductive content analysis, the following general dimensions were identified: 'importance of extra-time', 'rule changes', 'efficacy of extra-time hydro-nutritional provision', 'nutritional timing', 'future research directions', 'preparatory modulations' and 'recovery'. The majority of practitioners (63%) either agreed or strongly agreed that extra-time is an important period for determining success in knockout football match-play. When asked if a fourth substitution should be permitted in extra-time, 67% agreed. The use of hydro-nutritional strategies prior to extra-time was predominately considered important or very important. However; only 41% of practitioners felt that it was the most important time point for the use of nutritional products. A similar number of practitioners account (50%) and do not (50%) account for the potential of extra-time when training and preparing players and 89% of practitioners stated that extra-time influences recovery practices following matches. In the five minute break prior to extra-time, the following practices (in order of priority) were advocated to players: hydration, energy provision, massage, and tactical preparations. Additionally, 87% of practitioners advocate a particular nutritional supplementation strategy prior to extra-time. In order of importance, practitioners see the following as future research areas: nutritional interventions, fatigue responses, acute injury risk, recovery

  1. Four positive periodic solutions of a discrete time Lotka-Volterra competitive system with harvesting terms

    Directory of Open Access Journals (Sweden)

    Xinggui Liu


    Full Text Available In this paper, by using Mawhin's continuation theorem of coincidence degree theory, we establish the existence of at least four positive periodic solutions for a discrete time Lotka-Volterra competitive system with harvesting terms. An example is given to illustrate the effectiveness of our results.

  2. Reliability of fitness tests using methods and time periods common in sport and occupational management. (United States)

    Burnstein, Bryan D; Steele, Russell J; Shrier, Ian


    Fitness testing is used frequently in many areas of physical activity, but the reliability of these measurements under real-world, practical conditions is unknown. To evaluate the reliability of specific fitness tests using the methods and time periods used in the context of real-world sport and occupational management. Cohort study. Eighteen different Cirque du Soleil shows. Cirque du Soleil physical performers who completed 4 consecutive tests (6-month intervals) and were free of injury or illness at each session (n = 238 of 701 physical performers). Performers completed 6 fitness tests on each assessment date: dynamic balance, Harvard step test, handgrip, vertical jump, pull-ups, and 60-second jump test. We calculated the intraclass coefficient (ICC) and limits of agreement between baseline and each time point and the ICC over all 4 time points combined. Reliability was acceptable (ICC > 0.6) over an 18-month time period for all pairwise comparisons and all time points together for the handgrip, vertical jump, and pull-up assessments. The Harvard step test and 60-second jump test had poor reliability (ICC < 0.6) between baseline and other time points. When we excluded the baseline data and calculated the ICC for 6-month, 12-month, and 18-month time points, both the Harvard step test and 60-second jump test demonstrated acceptable reliability. Dynamic balance was unreliable in all contexts. Limit-of-agreement analysis demonstrated considerable intraindividual variability for some tests and a learning effect by administrators on others. Five of the 6 tests in this battery had acceptable reliability over an 18-month time frame, but the values for certain individuals may vary considerably from time to time for some tests. Specific tests may require a learning period for administrators.

  3. Modelling the time-variant dietary exposure of PCBs in China over the period 1930 to 2100. (United States)

    Zhao, Shizhen; Breivik, Knut; Jones, Kevin C; Sweetman, Andrew J


    This study aimed for the first time to reconstruct historical exposure profiles for PCBs to the Chinese population, by examining the combined effect of changing temporal emissions and dietary transition. A long-term (1930-2100) dynamic simulation of human exposure using realistic emission scenarios, including primary emissions, unintentional emissions and emissions from e-waste, combined with dietary transition trends was conducted by a multimedia fate model (BETR-Global) linked to a bioaccumulation model (ACC-HUMAN). The model predicted an approximate 30-year delay of peak body burden for PCB-153 in a 30-year-old Chinese female, compared to their European counterpart. This was mainly attributed to a combination of change in diet and divergent emission patterns in China. A fish-based diet was predicted to result in up to 8 times higher body burden than a vegetable-based diet (2010-2100). During the production period, a worst-case scenario assuming only consumption of imported food from a region with more extensive production and usage of PCBs would result in up to 4 times higher body burden compared to consumption of only locally produced food. However, such differences gradually diminished after cessation of production. Therefore, emission reductions in China alone may not be sufficient to protect human health for PCB-like chemicals, particularly during the period of mass production. The results from this study illustrate that human exposure is also likely to be dictated by inflows of PCBs via the environment, waste and food.

  4. The link between response time and preference, variance and processing heterogeneity in stated choice experiments

    DEFF Research Database (Denmark)

    Campbell, Danny; Mørkbak, Morten Raun; Olsen, Søren Bøye


    In this article we utilize the time respondents require to answer a self-administered online stated preference survey. While the effects of response time have been previously explored, this article proposes a different approach that explicitly recognizes the highly equivocal relationship between ...... between response time and utility coefficients, error variance and processing strategies. Our results thus emphasize the importance of considering response time when modeling stated choice data....... response time and respondents' choices. In particular, we attempt to disentangle preference, variance and processing heterogeneity and explore whether response time helps to explain these three types of heterogeneity. For this, we divide the data (ordered by response time) into approximately equal......-sized subsets, and then derive different class membership probabilities for each subset. We estimate a large number of candidate models and subsequently conduct a frequentist-based model averaging approach using information criteria to derive weights of evidence for each model. Our findings show a clear link...

  5. Efficient Fourier-based algorithms for time-periodic unsteady problems (United States)

    Gopinath, Arathi Kamath


    This dissertation work proposes two algorithms for the simulation of time-periodic unsteady problems via the solution of Unsteady Reynolds-Averaged Navier-Stokes (URANS) equations. These algorithms use a Fourier representation in time and hence solve for the periodic state directly without resolving transients (which consume most of the resources in a time-accurate scheme). In contrast to conventional Fourier-based techniques which solve the governing equations in frequency space, the new algorithms perform all the calculations in the time domain, and hence require minimal modifications to an existing solver. The complete space-time solution is obtained by iterating in a fifth pseudo-time dimension. Various time-periodic problems such as helicopter rotors, wind turbines, turbomachinery and flapping-wings can be simulated using the Time Spectral method. The algorithm is first validated using pitching airfoil/wing test cases. The method is further extended to turbomachinery problems, and computational results verified by comparison with a time-accurate calculation. The technique can be very memory intensive for large problems, since the solution is computed (and hence stored) simultaneously at all time levels. Often, the blade counts of a turbomachine are rescaled such that a periodic fraction of the annulus can be solved. This approximation enables the solution to be obtained at a fraction of the cost of a full-scale time-accurate solution. For a viscous computation over a three-dimensional single-stage rescaled compressor, an order of magnitude savings is achieved. The second algorithm, the reduced-order Harmonic Balance method is applicable only to turbomachinery flows, and offers even larger computational savings than the Time Spectral method. It simulates the true geometry of the turbomachine using only one blade passage per blade row as the computational domain. In each blade row of the turbomachine, only the dominant frequencies are resolved, namely

  6. Effects of combined linear and nonlinear periodic training on physical fitness and competition times in finswimmers. (United States)

    Yu, Kyung-Hun; Suk, Min-Hwa; Kang, Shin-Woo; Shin, Yun-A


    The purpose of this study was to investigate the effect of combined linear and nonlinear periodic training on physical fitness and competition times in finswimmers. The linear resistance training model (6 days/week) and nonlinear underwater training (4 days/week) were applied to 12 finswimmers (age, 16.08± 1.44 yr; career, 3.78± 1.90 yr) for 12 weeks. Body composition measures included weight, body mass index (BMI), percent fat, and fat-free mass. Physical fitness measures included trunk flexion forward, trunk extension backward, sargent jump, 1-repetition-maximum (1 RM) squat, 1 RM dead lift, knee extension, knee flexion, trunk extension, trunk flexion, and competition times. Body composition and physical fitness were improved after the 12-week periodic training program. Weight, BMI, and percent fat were significantly decreased, and trunk flexion forward, trunk extension backward, sargent jump, 1 RM squat, 1 RM dead lift, and knee extension (right) were significantly increased. The 50- and 100-m times significantly decreased in all 12 athletes. After 12 weeks of training, all finswimmers who participated in this study improved their times in a public competition. These data indicate that combined linear and nonlinear periodic training enhanced the physical fitness and competition times in finswimmers.

  7. Time to reach a given level of number of neutrons is stochastic analog of reactor period

    International Nuclear Information System (INIS)

    Ryazanov, V.V.


    In theory and in practice the operation of nuclear reactors to control the safety of the reactor is widely used deterministic value - the period of the reactor. It is proposed along with the period of the reactor using a stochastic analogue of this magnitude - a random amount of time to achieve a given level of a random process for the number of neutrons in the reactor. The paper discusses various features of the behavior of the mean and variance of time to achieve a specified level. This kind of features can be associated with impaired behavior of the reactor system. Introduced the value of time required to reach the level can be used to monitor and improve the safety of nuclear power plants

  8. Periodic Solution of Second-Order Hamiltonian Systems with a Change Sign Potential on Time Scales

    Directory of Open Access Journals (Sweden)

    You-Hui Su


    Full Text Available This paper is concerned with the second-order Hamiltonian system on time scales 𝕋 of the form uΔΔ(ρ(t+μb(t|u(t|μ−2u(t+∇¯H(t,u(t=0, Δ-a.e. t∈[0,T]𝕋 , u(0−u(T=uΔ(ρ(0−uΔ(ρ(T=0, where 0,T∈𝕋. By using the minimax methods in critical theory, an existence theorem of periodic solution for the above system is established. As an application, an example is given to illustrate the result. This is probably the first time the existence of periodic solutions for second-order Hamiltonian system on time scales has been studied by critical theory.

  9. Passive magnetic bearing systems stabilizer/bearing utilizing time-averaging of a periodic magnetic field (United States)

    Post, Richard F.


    A high-stiffness stabilizer/bearings for passive magnetic bearing systems is provide where the key to its operation resides in the fact that when the frequency of variation of the repelling forces of the periodic magnet array is large compared to the reciprocal of the growth time of the unstable motion, the rotating system will feel only the time-averaged value of the force. When the time-averaged value of the force is radially repelling by the choice of the geometry of the periodic magnet array, the Earnshaw-related unstable hit motion that would occur at zero rotational speed is suppressed when the system is rotating at operating speeds.

  10. Storing quantum information in XXZ spin rings with periodically time-controlled interactions

    International Nuclear Information System (INIS)

    Giampaolo, S M; Illuminati, F; Mazzarella, G


    We introduce a general scheme to realize massive quantum memories in simple systems of interacting qubits. Such systems are described by spin rings with XXZ intersite couplings of suitably time-periodically controlled amplitudes. We show that initially localized excitations undergo perfect periodic revivals, allowing for the simultaneous storage of arbitrary sets of different local states. This novel approach to the problem of storing quantum information hints at a new way to control and suppress the effect of decoherence on a quantum computer realized in a system with nonvanishing interactions between the constituent qubits

  11. Storing quantum information in XXZ spin rings with periodically time-controlled interactions

    Energy Technology Data Exchange (ETDEWEB)

    Giampaolo, S M; Illuminati, F; Mazzarella, G [Dipartimento di Fisica ' E. R. Caianiello' , Universita di Salerno, INFM UdR di Salerno, INFN Sezione di Napoli, Gruppo Collegato di Salerno, Via S. Allende, 84081 Baronissi, SA (Italy)


    We introduce a general scheme to realize massive quantum memories in simple systems of interacting qubits. Such systems are described by spin rings with XXZ intersite couplings of suitably time-periodically controlled amplitudes. We show that initially localized excitations undergo perfect periodic revivals, allowing for the simultaneous storage of arbitrary sets of different local states. This novel approach to the problem of storing quantum information hints at a new way to control and suppress the effect of decoherence on a quantum computer realized in a system with nonvanishing interactions between the constituent qubits.

  12. Plasticity of the intrinsic period of the human circadian timing system.

    Directory of Open Access Journals (Sweden)

    Frank A J L Scheer


    Full Text Available Human expeditions to Mars will require adaptation to the 24.65-h Martian solar day-night cycle (sol, which is outside the range of entrainment of the human circadian pacemaker under lighting intensities to which astronauts are typically exposed. Failure to entrain the circadian time-keeping system to the desired rest-activity cycle disturbs sleep and impairs cognitive function. Furthermore, differences between the intrinsic circadian period and Earth's 24-h light-dark cycle underlie human circadian rhythm sleep disorders, such as advanced sleep phase disorder and non-24-hour sleep-wake disorders. Therefore, first, we tested whether exposure to a model-based lighting regimen would entrain the human circadian pacemaker at a normal phase angle to the 24.65-h Martian sol and to the 23.5-h day length often required of astronauts during short duration space exploration. Second, we tested here whether such prior entrainment to non-24-h light-dark cycles would lead to subsequent modification of the intrinsic period of the human circadian timing system. Here we show that exposure to moderately bright light ( approximately 450 lux; approximately 1.2 W/m(2 for the second or first half of the scheduled wake episode is effective for entraining individuals to the 24.65-h Martian sol and a 23.5-h day length, respectively. Estimations of the circadian periods of plasma melatonin, plasma cortisol, and core body temperature rhythms collected under forced desynchrony protocols revealed that the intrinsic circadian period of the human circadian pacemaker was significantly longer following entrainment to the Martian sol as compared to following entrainment to the 23.5-h day. The latter finding of after-effects of entrainment reveals for the first time plasticity of the period of the human circadian timing system. Both findings have important implications for the treatment of circadian rhythm sleep disorders and human space exploration.

  13. Cryogenic digital data links for the liquid argon time projection chamber

    International Nuclear Information System (INIS)

    Liu, T; Gong, D; Liu, C; Xiang, A C; Ye, J; Hou, S; Su, D-S; Teng, P-K


    In this paper we present the cryogenic functionality of the components of data links for the Liquid Argon Time Projection Chamber (LArTPC), a potential far site detector technology of the Long-Baseline Neutrino Experiment (LBNE). We have confirmed that an LVDS driver can drive a 20-meter CAT5E twisted pair up to 1 gigabit per second at the liquid nitrogen temperature (77 K). We have verified that a commercial-off-the-shelf (COTS) serializer, a laser diode driver, laser diodes, optical fibers and connectors, and field-programming gate arrays (FPGA's) continue to function at 77 K. A variety of COTS resistors and capacitors have been tested at 77 K. All tests we have conducted show that the cryogenic digital data links for the liquid argon time projection chamber are promising.

  14. Copper, nickel and lead in lichen and tree bark transplants over different periods of time

    Energy Technology Data Exchange (ETDEWEB)

    Baptista, Mafalda S. [CIIMAR, Rua dos Bragas, 289, 4050-123 Porto (Portugal)], E-mail:; Vasconcelos, M. Teresa S.D. [CIIMAR, Rua dos Bragas, 289, 4050-123 Porto (Portugal); Chemistry Department, Faculty of Sciences, University of Porto, Rua do Campo Alegre, 687, 4169-071 Porto (Portugal)], E-mail:; Cabral, Joao Paulo [CIIMAR, Rua dos Bragas, 289, 4050-123 Porto (Portugal); Botany Department, Faculty of Sciences, University of Porto, Rua do Campo Alegre, 1191, 4150-181 Porto (Portugal)], E-mail:; Freitas, M. Carmo [ITN - Technological and Nuclear Institute, Reactor E.N. 10, 2686-953 Sacavem (Portugal)], E-mail:; Pacheco, Adriano M.G. [CVRM-IST - Technical University of Lisbon, Avenida Rovisco Pais, 1, 1049-001 Lisbon (Portugal)], E-mail:


    This work aimed at comparing the dynamics of atmospheric metal accumulation by the lichen Flavoparmelia caperata and bark of Platanus hybrida over different periods of time. Transplants were exposed in three Portuguese coastal cities. Samples were retrieved (1) every 2 months (discontinuous exposure), or (2) after 2-, 4-, 6-, 8- and 10-month periods (continuous exposure), and analysed for Cu, Ni and Pb. Airborne accumulation of metals was essentially independent of climatic factors. For both biomonitors [Pb] > [Ni] > [Cu] but Pb was the only element for which a consistent pattern of accumulation was observed, with the bark outperforming the lichen. The longest exposure periods hardly ever corresponded to the highest accumulation. This might have been partly because the biomonitors bound and released metals throughout the exposure, each with its own dynamics of accumulation, but both according to the environmental metal availability. - Lichen and tree bark have distinct dynamics of airborne metal accumulation.

  15. Copper, nickel and lead in lichen and tree bark transplants over different periods of time

    International Nuclear Information System (INIS)

    Baptista, Mafalda S.; Vasconcelos, M. Teresa S.D.; Cabral, Joao Paulo; Freitas, M. Carmo; Pacheco, Adriano M.G.


    This work aimed at comparing the dynamics of atmospheric metal accumulation by the lichen Flavoparmelia caperata and bark of Platanus hybrida over different periods of time. Transplants were exposed in three Portuguese coastal cities. Samples were retrieved (1) every 2 months (discontinuous exposure), or (2) after 2-, 4-, 6-, 8- and 10-month periods (continuous exposure), and analysed for Cu, Ni and Pb. Airborne accumulation of metals was essentially independent of climatic factors. For both biomonitors [Pb] > [Ni] > [Cu] but Pb was the only element for which a consistent pattern of accumulation was observed, with the bark outperforming the lichen. The longest exposure periods hardly ever corresponded to the highest accumulation. This might have been partly because the biomonitors bound and released metals throughout the exposure, each with its own dynamics of accumulation, but both according to the environmental metal availability. - Lichen and tree bark have distinct dynamics of airborne metal accumulation

  16. Nonequilibrium steady states and resonant tunneling in time-periodically driven systems with interactions (United States)

    Qin, Tao; Hofstetter, Walter


    Time-periodically driven systems are a versatile toolbox for realizing interesting effective Hamiltonians. Heating, caused by excitations to high-energy states, is a challenge for experiments. While most setups so far address the relatively weakly interacting regime, it is of general interest to study heating in strongly correlated systems. Using Floquet dynamical mean-field theory, we study nonequilibrium steady states (NESS) in the Falicov-Kimball model, with time-periodically driven kinetic energy or interaction. We systematically investigate the nonequilibrium properties of the NESS. For a driven kinetic energy, we show that resonant tunneling, where the interaction is an integer multiple of the driving frequency, plays an important role in the heating. In the strongly correlated regime, we show that this can be well understood using Fermi's golden rule and the Schrieffer-Wolff transformation for a time-periodically driven system. We furthermore demonstrate that resonant tunneling can be used to control the population of Floquet states to achieve "photodoping." For driven interactions introduced by an oscillating magnetic field near a widely adopted Feshbach resonance, we find that the double occupancy is strongly modulated. Our calculations apply to shaken ultracold-atom systems and to solid-state systems in a spatially uniform but time-dependent electric field. They are also closely related to lattice modulation spectroscopy. Our calculations are helpful to understand the latest experiments on strongly correlated Floquet systems.

  17. Abundant spontaneous VLFE activities in Cascadia during ETS and inter-ETS time periods (United States)

    Ghosh, A.; Hutchison, A. A.; Hawthorne, J.


    Very low frequency earthquakes (VLFEs) are discrete seismic events associated with episodic tremor and slip (ETS) events. They are rich in 20-50s energy and depleted in higher frequencies compared to regular local earthquakes of similar magnitudes. VLFEs can be as large as Mw 4.0, and potentially release much more seismic moment than the tremor/LFE activities, making them a critical event determining stress evolution during slow earthquakes [Ghosh et al., 2015]. Their underlying physics and relationship with tremor/LFE, however, are still unclear. In Cascadia, the majority of the VLFEs found so far are clustered near the areas of high geodetic slip during ETS events [Ghosh et al., 2015; Hutchison and Ghosh, 2016]. Interestingly, we found VLFE activity has its own dynamics and can occur independent of tremor/LFE activity. For example, during the 2014 ETS event in northern Cascadia, VLFEs are found to be asynchronous with tremor activity, both in space and time [Hutchison and Ghosh, 2016]. We use a matched filter technique to detect thousands of VLFEs over an ETS-cycle, and perhaps more interestingly, even between ETS events. VLFE activities peak during ETS events, but significant VLFE activity is detected during the inter-ETS time period. Analyses of strainmeter data near the VLFE locations suggest statistically significant strain rate increases during VLFE time periods compared to the background. We suggest that VLFE is a distinct type of seismic radiation different from tremor/LFE, and can operate independently from tremor activities. This is in contrast to a model suggesting that VLFE signals may be a result of many LFE signals arriving at seismic stations in a short time period [Gomberg et al., 2016]. We are making a consistent catalog of VLFE in Cascadia for longer time period. Systematic study of VLFEs is going to provide new insights into the mechanism of slow earthquakes and its relationship with tremor/LFE and slow slip.

  18. Stability of horizontal viscous fluid layers in a vertical arbitrary time periodic electric field (United States)

    Bandopadhyay, Aditya; Hardt, Steffen


    The stability of a horizontal interface between two viscous fluids, one of which is conducting and the other is dielectric, acted upon by a vertical time-periodic electric field is considered theoretically. The two fluids are bounded by electrodes separated by a finite distance. For an applied ac electric field, the unstable interface deforms in a time periodic manner, owing to the time dependent Maxwell stress, and is characterized by the oscillation frequency which may or may not be the same as the frequency of the ac electric field. The stability curve, which relates the critical voltage, manifested through the Mason number—the ratio of normal electric stress and viscous stress, and the instability wavenumber at the onset of the instability, is obtained by means of the Floquet theory for a general arbitrary time periodic electric field. The limit of vanishing viscosities is shown to be in excellent agreement with the marginal stability curves predicted by means of a Mathieu equation. The influence of finite viscosity and electrode separation is discussed in relation to the ideal case of inviscid fluids. The methodology to obtain the marginal stability curves developed here is applicable to any arbitrary but time periodic signal, as demonstrated for the case of a signal with two different frequencies, and four different frequencies with a dc offset. The mode coupling in the interfacial normal stress leads to appearance of harmonic and subharmonic modes, characterized by the frequency of the oscillating interface at an integral or half-integral multiple of the applied frequency, respectively. This is in contrast to the application of a voltage with a single frequency which always leads to a harmonic mode oscillation of the interface. Whether a harmonic or subharmonic mode is the most unstable one depends on details of the excitation signal.

  19. Time with friends and physical activity as mechanisms linking obesity and television viewing among youth. (United States)

    Vandewater, Elizabeth A; Park, Seoung Eun; Hébert, Emily T; Cummings, Hope M


    Though bivariate relationships between childhood obesity, physical activity, friendships and television viewing are well documented, empirical assessment of the extent to which links between obesity and television may be mediated by these factors is scarce. This study examines the possibility that time with friends and physical activity are potential mechanisms linking overweight/obesity to television viewing in youth. Data were drawn from children ages 10-18 years old (M = 13.81, SD = 2.55) participating in the 2002 wave of Child Development Supplement (CDS) to the Panel Study of Income Dynamics (PSID) (n = 1,545). Data were collected both directly and via self-report from children and their parents. Path analysis was employed to examine a model whereby the relationships between youth overweight/obesity and television viewing were mediated by time spent with friends and moderate-to-vigorous physical activity (MVPA). Overweight/obesity was directly related to less time spent with friends, but not to MVPA. Time spent with friends was directly and positively related to MVPA, and directly and negatively related to time spent watching television without friends. In turn, MVPA was directly and negatively related to watching television without friends. There were significant indirect effects of both overweight/obesity and time with friends on television viewing through MVPA, and of overweight/obesity on MVPA through time with friends. Net of any indirect effects, the direct effect of overweight/obesity on television viewing remained. The final model fit the data extremely well (χ2 = 5.77, df = 5, ptelevision viewing in youth. These findings highlight the importance of moving from examinations of bivariate relationships between weight status and television viewing to more nuanced explanatory models which attempt to identify and unpack the possible mechanisms linking them.

  20. Stochastic resonance in a time-delayed asymmetric bistable system with mixed periodic signal

    International Nuclear Information System (INIS)

    Yong-Feng, Guo; Wei, Xu; Liang, Wang


    This paper studies the phenomenon of stochastic resonance in an asymmetric bistable system with time-delayed feedback and mixed periodic signal by using the theory of signal-to-noise ratio in the adiabatic limit. A general approximate Fokker–Planck equation and the expression of the signal-to-noise ratio are derived through the small time delay approximation at both fundamental harmonics and mixed harmonics. The effects of the additive noise intensity Q, multiplicative noise intensity D, static asymmetry r and delay time τ on the signal-to-noise ratio are discussed. It is found that the higher mixed harmonics and the static asymmetry r can restrain stochastic resonance, and the delay time τ can enhance stochastic resonance. Moreover, the longer the delay time τ is, the larger the additive noise intensity Q and the multiplicative noise intensity D are, when the stochastic resonance appears. (general)

  1. Stochastic model stationarization by eliminating the periodic term and its effect on time series prediction (United States)

    Moeeni, Hamid; Bonakdari, Hossein; Fatemi, Seyed Ehsan


    Because time series stationarization has a key role in stochastic modeling results, three methods are analyzed in this study. The methods are seasonal differencing, seasonal standardization and spectral analysis to eliminate the periodic effect on time series stationarity. First, six time series including 4 streamflow series and 2 water temperature series are stationarized. The stochastic term for these series obtained with ARIMA is subsequently modeled. For the analysis, 9228 models are introduced. It is observed that seasonal standardization and spectral analysis eliminate the periodic term completely, while seasonal differencing maintains seasonal correlation structures. The obtained results indicate that all three methods present acceptable performance overall. However, model accuracy in monthly streamflow prediction is higher with seasonal differencing than with the other two methods. Another advantage of seasonal differencing over the other methods is that the monthly streamflow is never estimated as negative. Standardization is the best method for predicting monthly water temperature although it is quite similar to seasonal differencing, while spectral analysis performed the weakest in all cases. It is concluded that for each monthly seasonal series, seasonal differencing is the best stationarization method in terms of periodic effect elimination. Moreover, the monthly water temperature is predicted with more accuracy than monthly streamflow. The criteria of the average stochastic term divided by the amplitude of the periodic term obtained for monthly streamflow and monthly water temperature were 0.19 and 0.30, 0.21 and 0.13, and 0.07 and 0.04 respectively. As a result, the periodic term is more dominant than the stochastic term for water temperature in the monthly water temperature series compared to streamflow series.

  2. Primate enamel evinces long period biological timing and regulation of life history. (United States)

    Bromage, Timothy G; Hogg, Russell T; Lacruz, Rodrigo S; Hou, Chen


    The factor(s) regulating the combination of traits that define the overall life history matrix of mammalian species, comprising attributes such as brain and body weight, age at sexual maturity, lifespan and others, remains a complete mystery. The principal objectives of the present research are (1) to provide evidence for a key variable effecting life history integration and (2) to provide a model for how one would go about investigating the metabolic mechanisms responsible for this rhythm. We suggest here that a biological rhythm with a period greater than the circadian rhythm is responsible for observed variation in primate life history. Evidence for this rhythm derives from studies of tooth enamel formation. Enamel contains an enigmatic periodicity in its microstructure called the striae of Retzius, which develops at species specific intervals in units of whole days. We refer to this enamel rhythm as the repeat interval (RI). For primates, we identify statistically significant relationships between RI and all common life history traits. Importantly, RI also correlates with basal and specific metabolic rates. With the exception of estrous cyclicity, all relationships share a dependence upon body mass. This dependence on body mass informs us that some aspect of metabolism is responsible for periodic energy allocations at RI timescales, regulating cell proliferation rates and growth, thus controlling the pace, patterning, and co-variation of life history traits. Estrous cyclicity relates to the long period rhythm in a body mass-independent manner. The mass-dependency and -independency of life history relationships with RI periodicity align with hypothalamic-mediated neurosecretory anterior and posterior pituitary outputs. We term this period the Havers-Halberg Oscillation (HHO), in reference to Clopton Havers, a 17th Century hard tissue anatomist, and Franz Halberg, a long-time explorer of long-period rhythms. We propose a mathematical model that may help elucidate

  3. Natural convection in square enclosure induced by inner circular cylinder with time-periodic pulsating temperature

    KAUST Repository

    Huang, Zhu


    The periodic unsteady natural convection flow and heat transfer in a square enclosure containing a concentric circular cylinder is numerically studied. The temperature of the inner circular cylinder fluctuates periodically with time at higher averaged value while the temperature of the enclosure keeps lower constant, and the natural convection is driven by the temperature difference. The two-dimensional natural convection is simulated with high accuracy temporal spectral method and local radial basis functions method. The Rayleigh number is studied in the range 103 ≤ Ra ≤ 106, the temperature pulsating period ranges from 0.01 to 100 and the temperature pulsating amplitudes are a = 0.5, 1.0 and 1.5. Numerical results reveal that the fluid flow and heat transfer is strongly dependent on the pulsating temperature of inner cylinder. Comparing with the steady state natural convection, the heat transfer is enhanced generally for the time-periodic unsteady natural convection, and the local maximum heat transfer rate is observed for Ra = 105 and 106. Moreover, the phenomenon of backward heat transfer is discussed quantitatively. Also, the influence of pulsating temperature on the unsteady fluid flow and heat transfer are discussed and analyzed.

  4. Tracing temperature in a nanometer size region in a picosecond time period. (United States)

    Nakajima, Kaoru; Kitayama, Takumi; Hayashi, Hiroaki; Matsuda, Makoto; Sataka, Masao; Tsujimoto, Masahiko; Toulemonde, Marcel; Bouffard, Serge; Kimura, Kenji


    Irradiation of materials with either swift heavy ions or slow highly charged ions leads to ultrafast heating on a timescale of several picosecond in a region of several nanometer. This ultrafast local heating result in formation of nanostructures, which provide a number of potential applications in nanotechnologies. These nanostructures are believed to be formed when the local temperature rises beyond the melting or boiling point of the material. Conventional techniques, however, are not applicable to measure temperature in such a localized region in a short time period. Here, we propose a novel method for tracing temperature in a nanometer region in a picosecond time period by utilizing desorption of gold nanoparticles around the ion impact position. The feasibility is examined by comparing with the temperature evolution predicted by a theoretical model.

  5. The effect of rinsing time periods on wettability of elastomeric impression materials: in vitro study

    Directory of Open Access Journals (Sweden)

    Özlem Acar


    Full Text Available OBJECTIVE: The aim of this study was to determine whether different rinsing time periods affected the wettability of polymerized elastomeric impression materials. MATERIALS AND METHOD: Panasil Contact Plus (PCP, Panasil Contact Non-Surfactant (PCNS, Panasil Initial Contact (PIC, Express (EXP and Impregum (IMP impression materials were tested. Standardized samples were rinsed with water for 10 s, 15 s or 20 s, and the wettability was determined by contact angle measurement through an evaluation period of 60 seconds (n=7. Non-rinsed groups were used as control. Measurements were made at 5 time points (at 0, 6, 15, 30 and 60 seconds. Kruskal Wallis test and Conover’s multiple comparison tests were used for all multiple comparisons. Bonferroni adjustment was applied for controlling Type I error (p0.002. CONCLUSION: Rinsing the surfactant-containing polyvinylsiloxane impression materials decreased their wettability, whereas no such effect was seen for the surfactant free polyvinylsiloxane and polyether impression materials.

  6. Periodic solution for state-dependent impulsive shunting inhibitory CNNs with time-varying delays. (United States)

    Şaylı, Mustafa; Yılmaz, Enes


    In this paper, we consider existence and global exponential stability of periodic solution for state-dependent impulsive shunting inhibitory cellular neural networks with time-varying delays. By means of B-equivalence method, we reduce these state-dependent impulsive neural networks system to an equivalent fix time impulsive neural networks system. Further, by using Mawhin's continuation theorem of coincide degree theory and employing a suitable Lyapunov function some new sufficient conditions for existence and global exponential stability of periodic solution are obtained. Previous results are improved and extended. Finally, we give an illustrative example with numerical simulations to demonstrate the effectiveness of our theoretical results. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Observed variations in U.S. frost timing linked to atmospheric circulation patterns. (United States)

    Strong, Courtenay; McCabe, Gregory J


    Several studies document lengthening of the frost-free season within the conterminous United States (U.S.) over the past century, and report trends in spring and fall frost timing that could stem from hemispheric warming. In the absence of warming, theory and case studies link anomalous frost timing to atmospheric circulation anomalies. However, recent efforts to relate a century of observed changes in U.S. frost timing to various atmospheric circulations yielded only modest correlations, leaving the relative importance of circulation and warming unclear. Here, we objectively partition the U.S. into four regions and uncover atmospheric circulations that account for 25-48% of spring and fall-frost timing. These circulations appear responsive to historical warming, and they consistently account for more frost timing variability than hemispheric or regional temperature indices. Reliable projections of future variations in growing season length depend on the fidelity of these circulation patterns in global climate models.

  8. CMOS continuous-time adaptive equalizers for high-speed serial links

    CERN Document Server

    Gimeno Gasca, Cecilia; Aldea Chagoyen, Concepción


    This book introduces readers to the design of adaptive equalization solutions integrated in standard CMOS technology for high-speed serial links. Since continuous-time equalizers offer various advantages as an alternative to discrete-time equalizers at multi-gigabit rates, this book provides a detailed description of continuous-time adaptive equalizers design - both at transistor and system levels-, their main characteristics and performances. The authors begin with a complete review and analysis of the state of the art of equalizers for wireline applications, describing why they are necessary, their types, and their main applications. Next, theoretical fundamentals of continuous-time adaptive equalizers are explored. Then, new structures are proposed to implement the different building blocks of the adaptive equalizer: line equalizer, loop-filters, power comparator, etc.  The authors demonstrate the design of a complete low-power, low-voltage, high-speed, continuous-time adaptive equalizer. Finally, a cost-...

  9. Mimicking Nonequilibrium Steady States with Time-Periodic Driving (Open Source) (United States)


    construction does not require the solution of any differential equations , only linear algebraic equations . By contrast, a mapping in the opposite...set of algebraic linear equations . The mapping between NESS and SP presented above was not intended as a set of operational instructions for... differential equations with time-periodic parameters. Typically, this can only be done numerically. In some applications, transition rates are constrained by


    International Nuclear Information System (INIS)

    Mikadze, I.; Namchevadze, T.; Gobiani, I.


    There is proposed a generalized mathematical model of the queuing system with time redundancy without preliminary checking of the queuing system at transition from the free state into the engaged one. The model accounts for various failures of the queuing system detected by continuous instrument control, periodic control, control during recovery and the failures revealed immediately after accumulation of a certain number of failures. The generating function of queue length in both stationary and nonstationary modes was determined. (author)

  11. Timing of millennial-scale climate change in Antarctica and Greenland during the last glacial period

    DEFF Research Database (Denmark)

    Blunier, T; Brook, E J


    A precise relative chronology for Greenland and West Antarctic paleotemperature is extended to 90,000 years ago, based on correlation of atmospheric methane records from the Greenland Ice Sheet Project 2 and Byrd ice cores. Over this period, the onset of seven major millennial-scale warmings in A....... This pattern provides further evidence for the operation of a "bipolar see-saw" in air temperatures and an oceanic teleconnection between the hemispheres on millennial time scales....

  12. Numerical detection of unstable periodic orbits in continuous-time dynamical systems with chaotic behaviors

    Directory of Open Access Journals (Sweden)

    Y. Saiki


    Full Text Available An infinite number of unstable periodic orbits (UPOs are embedded in a chaotic system which models some complex phenomenon. Several algorithms which extract UPOs numerically from continuous-time chaotic systems have been proposed. In this article the damped Newton-Raphson-Mees algorithm is reviewed, and some important techniques and remarks concerning the practical numerical computations are exemplified by employing the Lorenz system.

  13. Period-doubling bifurcation and chaos control in a discrete-time mosquito model

    Directory of Open Access Journals (Sweden)

    Qamar Din


    Full Text Available This article deals with the study of some qualitative properties of a discrete-time mosquito Model. It is shown that there exists period-doubling bifurcation for wide range of bifurcation parameter for the unique positive steady-state of given system. In order to control the bifurcation we introduced a feedback strategy. For further confirmation of complexity and chaotic behavior largest Lyapunov exponents are plotted.

  14. Time-varying singular value decomposition for periodic transient identification in bearing fault diagnosis (United States)

    Zhang, Shangbin; Lu, Siliang; He, Qingbo; Kong, Fanrang


    For rotating machines, the defective faults of bearings generally are represented as periodic transient impulses in acquired signals. The extraction of transient features from signals has been a key issue for fault diagnosis. However, the background noise reduces identification performance of periodic faults in practice. This paper proposes a time-varying singular value decomposition (TSVD) method to enhance the identification of periodic faults. The proposed method is inspired by the sliding window method. By applying singular value decomposition (SVD) to the signal under a sliding window, we can obtain a time-varying singular value matrix (TSVM). Each column in the TSVM is occupied by the singular values of the corresponding sliding window, and each row represents the intrinsic structure of the raw signal, namely time-singular-value-sequence (TSVS). Theoretical and experimental analyses show that the frequency of TSVS is exactly twice that of the corresponding intrinsic structure. Moreover, the signal-to-noise ratio (SNR) of TSVS is improved significantly in comparison with the raw signal. The proposed method takes advantages of the TSVS in noise suppression and feature extraction to enhance fault frequency for diagnosis. The effectiveness of the TSVD is verified by means of simulation studies and applications to diagnosis of bearing faults. Results indicate that the proposed method is superior to traditional methods for bearing fault diagnosis.

  15. Algorithm for determining two-periodic steady-states in AC machines directly in time domain

    Directory of Open Access Journals (Sweden)

    Sobczyk Tadeusz J.


    Full Text Available This paper describes an algorithm for finding steady states in AC machines for the cases of their two-periodic nature. The algorithm enables to specify the steady-state solution identified directly in time domain despite of the fact that two-periodic waveforms are not repeated in any finite time interval. The basis for such an algorithm is a discrete differential operator that specifies the temporary values of the derivative of the two-periodic function in the selected set of points on the basis of the values of that function in the same set of points. It allows to develop algebraic equations defining the steady state solution reached in a chosen point set for the nonlinear differential equations describing the AC machines when electrical and mechanical equations should be solved together. That set of those values allows determining the steady state solution at any time instant up to infinity. The algorithm described in this paper is competitive with respect to the one known in literature an approach based on the harmonic balance method operated in frequency domain.

  16. Improved long-term outcomes after resection of pancreatic adenocarcinoma: a comparison between two time periods. (United States)

    Serrano, Pablo E; Cleary, Sean P; Dhani, Neesha; Kim, Peter T W; Greig, Paul D; Leung, Kenneth; Moulton, Carol-Anne; Gallinger, Steven; Wei, Alice C


    Despite reduced perioperative mortality and routine use of adjuvant therapy following pancreatectomy for pancreatic ductal adenocarcinoma (PDAC), improvement in long-term outcome has been difficult to ascertain. This study compares outcomes in patients undergoing resection for PDAC within a single, high-volume academic institution over two sequential time periods. Retrospective review of patients with resected PDAC, in two cohorts: period 1 (P1), 1991-2000; and period 2 (P2), 2001-2010. Univariate and multivariate analyses using the Cox proportional hazards model were performed to determine prognostic factors associated with long-term survival. Survival was evaluated using Kaplan-Meier analyses. A total of 179 pancreatectomies were performed during P1 and 310 during P2. Perioperative mortality was 6.7 % (12/179) in P1 and 1.6 % (5/310) in P2 (p = 0.003). P2 had a greater number of lymph nodes resected (17 [0-50] vs. 7 [0-31]; p P2 (p P2 (p < 0.001). Factors associated with improved long-term survival remain comparable over time. Short- and long-term survival for patients with resected PDAC has improved over time due to decreased perioperative mortality and increased use of adjuvant therapy, although the proportion of 5-year survivors remains small.

  17. Evaluation of 'period-generated' control laws for the time-optimal control of reactor power

    International Nuclear Information System (INIS)

    Bernard, J.A.


    Time-Optimal control of neutronic power has recently been achieved by developing control laws that determine the actuator mechanism velocity necessary to produce a specified reactor period. These laws are designated as the 'MIT-SNL Period-Generated Minimum Time Control Laws'. Relative to time-optimal response, they function by altering the rate of change of reactivity so that the instantaneous period is stepped from infinity to its minimum allowed value, held at that value until the desired power level is attained, and then stepped back to infinity. The results of a systematic evaluation of these laws are presented. The behavior of each term in the control laws is shown and the capability of these laws to control properly the reactor power is demonstrated. Factors affecting the implementation of these laws, such as the prompt neutron lifetime and the differential reactivity worth of the actuators, are discussed. Finally, the results of an experimental study in which these laws were used to adjust the power of the 5 MWt MIT Research Reactor are shown. The information presented should be of interest to those designing high performance control systems for test, spacecraft, or, in certain instances, commercial reactors

  18. A technique to detect periodic and non-periodic ultra-rapid flux time variations with standard radio-astronomical data (United States)

    Borra, Ermanno F.; Romney, Jonathan D.; Trottier, Eric


    We demonstrate that extremely rapid and weak periodic and non-periodic signals can easily be detected by using the autocorrelation of intensity as a function of time. We use standard radio-astronomical observations that have artificial periodic and non-periodic signals generated by the electronics of terrestrial origin. The autocorrelation detects weak signals that have small amplitudes because it averages over long integration times. Another advantage is that it allows a direct visualization of the shape of the signals, while it is difficult to see the shape with a Fourier transform. Although Fourier transforms can also detect periodic signals, a novelty of this work is that we demonstrate another major advantage of the autocorrelation, that it can detect non-periodic signals while the Fourier transform cannot. Another major novelty of our work is that we use electric fields taken in a standard format with standard instrumentation at a radio observatory and therefore no specialized instrumentation is needed. Because the electric fields are sampled every 15.625 ns, they therefore allow detection of very rapid time variations. Notwithstanding the long integration times, the autocorrelation detects very rapid intensity variations as a function of time. The autocorrelation could also detect messages from Extraterrestrial Intelligence as non-periodic signals.

  19. Self-publishing of Lithuanian cultural periodicals in Soviet and contemporary times

    Directory of Open Access Journals (Sweden)

    Asta Urbanaviciute


    Full Text Available The aim of this article is to analyse self-publishing trends of Lithuanian cultural periodicals focusing on the historical and contemporary contexts. The article provides an overview of the reasons for historical cultural periodical self-published texts, known as samizdats, to appear, as well as their publishing and circulation trends in Lithuania. It also analyses what contemporary cultural self-publishing is: whether it is a completely independent, logical consequence of the digital age, which emerged under favourable circumstances, or if it can be characterized as having something in common with the past experiences. The most active years of the periodical underground press publishing in Soviet Lithuanian self-publishing development were between 1975 and 1981. Self-published texts ideologically diverged into three main directions: religious, civic, and cultural-artistic. A total of 22 publications were being published for a longer or shorter period of time. While analysing contemporary cultural self-publishing topics, the report focuses only on online cultural texts, irrespective of the printed ones. Survey method was used to find out how much and in what aspect modern Internet users perceive historical periodical self-publishing, and how and in what aspect they value modern cultural self-published texts. The results show that 18-35-year-old respondents have not acquired the skills necessary to analyse samizdat publishing. They associate the word self-publishing with digital texts only, which due to favourable conditions spread easily through social networks and blogs. In the era of advancing computer technologies and the Internet, every person who has the time and desire may become a developer, an author, or at least a disseminator of information: this tradition is becoming more and more topical and quite frequently – an almost self-evident phenomenon.

  20. Impaired Representation of Time in Schizophrenia Is Linked to Positive Symptoms and Cognitive Demand.

    Directory of Open Access Journals (Sweden)

    Jutta Peterburs

    Full Text Available Time processing critically relies on the mesencephalic dopamine system and striato-prefrontal projections and has thus been suggested to play a key role in schizophrenia. Previous studies have provided evidence for an acceleration of the internal clock in schizophrenia that may be linked to dopaminergic pathology. The present study aimed to assess the relationship between altered time processing in schizophrenia and symptom manifestation in 22 patients and 22 controls. Subjects were required to estimate the time needed for a visual stimulus to complete a horizontal movement towards a target position on trials of varying cognitive demand. It was hypothesized that patients - compared to controls - would be less accurate at estimating the movement time, and that this effect would be modulated by symptom manifestation and task difficulty. In line with the notion of an accelerated internal clock due to dopaminergic dysregulation, particularly patients with severe positive symptoms were expected to underestimate movement time. However, if altered time perception in schizophrenia was better explained in terms of cognitive deficits, patients with severe negative symptoms should be specifically impaired, while generally, task performance should correlate with measures of processing speed and cognitive flexibility. Patients underestimated movement time on more demanding trials, although there was no link to disease-related cognitive dysfunction. Task performance was modulated by symptom manifestation. Impaired estimation of movement time was significantly correlated with PANSS positive symptom scores, with higher positive symptom scores associated with stronger underestimation of movement time. The present data thus support the notion of a deficit in anticipatory and predictive mechanisms in schizophrenia that is modulated both by symptom manifestation and by cognitive demand.

  1. mtDNA from the early Bronze Age to the Roman period suggests a genetic link between the Indian subcontinent and Mesopotamian cradle of civilization.

    Directory of Open Access Journals (Sweden)

    Henryk W Witas

    Full Text Available Ancient DNA methodology was applied to analyse sequences extracted from freshly unearthed remains (teeth of 4 individuals deeply deposited in slightly alkaline soil of the Tell Ashara (ancient Terqa and Tell Masaikh (ancient Kar-Assurnasirpal Syrian archaeological sites, both in the middle Euphrates valley. Dated to the period between 2.5 Kyrs BC and 0.5 Kyrs AD the studied individuals carried mtDNA haplotypes corresponding to the M4b1, M49 and/or M61 haplogroups, which are believed to have arisen in the area of the Indian subcontinent during the Upper Paleolithic and are absent in people living today in Syria. However, they are present in people inhabiting today's Tibet, Himalayas, India and Pakistan. We anticipate that the analysed remains from Mesopotamia belonged to people with genetic affinity to the Indian subcontinent since the distribution of identified ancient haplotypes indicates solid link with populations from the region of South Asia-Tibet (Trans-Himalaya. They may have been descendants of migrants from much earlier times, spreading the clades of the macrohaplogroup M throughout Eurasia and founding regional Mesopotamian groups like that of Terqa or just merchants moving along trade routes passing near or through the region. None of the successfully identified nuclear alleles turned out to be ΔF508 CFTR, LCT-13910T or Δ32 CCR5.

  2. Severe combined immunodeficiency in Greek children over a 20-year period: rarity of γc-chain deficiency (X-linked) type. (United States)

    Michos, Athanasios; Tzanoudaki, Marianna; Villa, Anna; Giliani, Silvia; Chrousos, George; Kanariou, Maria


    Severe combined immunodeficiencies (SCID) are a heterogeneous group of genetic disorders characterized by a blockade or impairment of both cellular and humoral immunity. Several epidemiological studies in different geographic areas have shown that the most common type of SCID affecting almost half of these patients is the X-linked common γ-chain (γ(c)) deficiency. The objective of the study was to document the incidence and types of SCID in our area. We conducted a retrospective analysis of patients who were diagnosed with SCID in the major immunology center in Greece for a 20-year period. During the study period, 30 children from 27 unrelated families with final diagnosis of SCID were identified. The incidence of SCID in Greece is estimated at 1.7 cases per 100,000 live births. Out of 30 children, 19 were boys (63.3%) and 26 (86.7%) had Greek maternal origin. Lymphocyte immunophenotypes that were identified were T(-)B(-)NK(+) in 12 (40%) children, T(-)B(+)NK(-) in six (20%), T(-)B(+)NK(+) in three (10%), T(-)B(-)NK(-) in two (6.7%) and T(+)B(+/-)NK(+) in seven (23.4%) (among them, four [13.4%] females with Omenn's syndrome). Molecular diagnosis was available for 12 children: γ(c) (2) with non Greek maternal origin, Jak3 (2), Rag1 (2), Artemis (3), ADA deficiency (2), PNP deficiency (1). Out of the 26 children of Greek maternal origin diagnosed with SCID representing 23 distinct families, only two (8.7%) had lymphocyte immunophenotype compatible with γ(c)-chain gene mutation (no molecular testing or enough DNA was available for them at the time of diagnosis). Findings of the present study suggest that, for unknown reasons, mutations of the γ(c) chain of several cytokine receptors have a rare occurrence in our area.

  3. Time development in the early history of social networks: link stabilization, group dynamics, and segregation. (United States)

    Bruun, Jesper; Bearden, Ian G


    Studies of the time development of empirical networks usually investigate late stages where lasting connections have already stabilized. Empirical data on early network history are rare but needed for a better understanding of how social network topology develops in real life. Studying students who are beginning their studies at a university with no or few prior connections to each other offers a unique opportunity to investigate the formation and early development of link patterns and community structure in social networks. During a nine week introductory physics course, first year physics students were asked to identify those with whom they communicated about problem solving in physics during the preceding week. We use these students' self reports to produce time dependent student interaction networks. We investigate these networks to elucidate possible effects of different student attributes in early network formation. Changes in the weekly number of links show that while roughly half of all links change from week to week, students also reestablish a growing number of links as they progress through their first weeks of study. Using the Infomap community detection algorithm, we show that the networks exhibit community structure, and we use non-network student attributes, such as gender and end-of-course grade to characterize communities during their formation. Specifically, we develop a segregation measure and show that students structure themselves according to gender and pre-organized sections (in which students engage in problem solving and laboratory work), but not according to end-of-coure grade. Alluvial diagrams of consecutive weeks' communities show that while student movement between groups are erratic in the beginning of their studies, they stabilize somewhat towards the end of the course. Taken together, the analyses imply that student interaction networks stabilize quickly and that students establish collaborations based on who is immediately

  4. An Internet-Based Real-Time Audiovisual Link for Dual MEG Recordings.

    Directory of Open Access Journals (Sweden)

    Andrey Zhdanov

    Full Text Available Most neuroimaging studies of human social cognition have focused on brain activity of single subjects. More recently, "two-person neuroimaging" has been introduced, with simultaneous recordings of brain signals from two subjects involved in social interaction. These simultaneous "hyperscanning" recordings have already been carried out with a spectrum of neuroimaging modalities, such as functional magnetic resonance imaging (fMRI, electroencephalography (EEG, and functional near-infrared spectroscopy (fNIRS.We have recently developed a setup for simultaneous magnetoencephalographic (MEG recordings of two subjects that communicate in real time over an audio link between two geographically separated MEG laboratories. Here we present an extended version of the setup, where we have added a video connection and replaced the telephone-landline-based link with an Internet connection. Our setup enabled transmission of video and audio streams between the sites with a one-way communication latency of about 130 ms. Our software that allows reproducing the setup is publicly available.We demonstrate that the audiovisual Internet-based link can mediate real-time interaction between two subjects who try to mirror each others' hand movements that they can see via the video link. All the nine pairs were able to synchronize their behavior. In addition to the video, we captured the subjects' movements with accelerometers attached to their index fingers; we determined from these signals that the average synchronization accuracy was 215 ms. In one subject pair we demonstrate inter-subject coherence patterns of the MEG signals that peak over the sensorimotor areas contralateral to the hand used in the task.

  5. On an nth-order infinitesimal generator and time-dependent operator differential equation with a strongly almost periodic solution

    Directory of Open Access Journals (Sweden)

    Aribindi Satyanarayan Rao


    Full Text Available In a Banach space, if u is a Stepanov almost periodic solution of a certain nth-order infinitesimal generator and time-dependent operator differential equation with a Stepanov almost periodic forcing function, then u,u′,…,u (n−2 are all strongly almost periodic and u (n−1 is weakly almost periodic.

  6. Dynamic effective properties of heterogeneous geological formations with spherical inclusions under periodic time variations (United States)

    Rabinovich, A.; Dagan, G.; Miloh, T.


    In unsteady groundwater flow (or similar processes of heat/electrical conduction), the heterogeneous medium structure is characterized by two random properties, the conductivity K and the specific storativity S. The average head field ⟨H ⟩and the associated effective properties Kef, Sef are determined for a layer with a periodic head drop between boundaries, such that H is periodic in time, and a medium made up of a matrix with a dilute concentration of spherical inclusions. In the common quasi-steady approximation, Kef is equal to the classical steady solution while Sef = SA, the arithmetic mean. We derive expressions for the frequency dependent Kef, Sef, which are generally complex, i.e., dynamic. The main result is the delineation of the ranges of the parameters: dimensionless frequency (ω) and contrasts of conductivity (κ) and storativity (s) between the matrix and the inclusions, for which dynamic effects are significant.

  7. Current density waves in open mesoscopic rings driven by time-periodic magnetic fluxes

    International Nuclear Information System (INIS)

    Yan Conghua; Wei Lianfu


    Quantum coherent transport through open mesoscopic Aharonov-Bohm rings (driven by static fluxes) have been studied extensively. Here, by using quantum waveguide theory and the Floquet theorem we investigate the quantum transport of electrons along an open mesoscopic ring threaded by a time-periodic magnetic flux. We predicate that current density waves could be excited along such an open ring. As a consequence, a net current could be generated along the lead with only one reservoir, if the lead additionally connects to such a normal-metal loop driven by the time-dependent flux. These phenomena could be explained by photon-assisted processes, due to the interaction between the transported electrons and the applied oscillating external fields. We also discuss how the time-average currents (along the ring and the lead) depend on the amplitude and frequency of the applied oscillating fluxes.

  8. Prefrontal activity during response inhibition decreases over time in the postpartum period. (United States)

    Bannbers, Elin; Gingnell, Malin; Engman, Jonas; Morell, Arvid; Sylvén, Sara; Skalkidou, Alkistis; Kask, Kristiina; Bäckström, Torbjörn; Wikström, Johan; Poromaa, Inger Sundström


    The postpartum period is characterized by complex hormonal changes, but human imaging studies in the postpartum period have thus far predominantly focused on the neural correlates of maternal behavior or postpartum depression, whereas longitudinal studies on neural correlates of cognitive function across the postpartum period in healthy women are lacking. The aim of this study was to longitudinally examine response inhibition, as a measure of executive function, during the postpartum period and its neural correlates in healthy postpartum women and non-postpartum controls. Thirteen healthy postpartum women underwent event-related functional magnetic resonance imaging while performing a Go/NoGo task. The first assessment was made within 48 h of delivery, and the second at 4-7 weeks postpartum. In addition, 13 healthy women examined twice during the menstrual cycle were included as non-postpartum controls. In postpartum women region of interest analyses revealed task-related decreased activations in the right inferior frontal gyrus, right anterior cingulate, and bilateral precentral gyri at the late postpartum assessment. Generally, postpartum women displayed lower activity during response inhibition in the bilateral inferior frontal gyri and precentral gyri compared to non-postpartum controls. No differences in performance on the Go/NoGo task were found between time-points or between groups. In conclusion, this study has discovered that brain activity in prefrontal areas during a response inhibition task decreases throughout the course of the first postpartum weeks and is lower than in non-postpartum controls. Further studies on the normal adaptive brain activity changes that occur during the postpartum period are warranted. Copyright © 2012 Elsevier B.V. All rights reserved.

  9. Identifying Time Periods of Minimal Thermal Gradient for Temperature-Driven Structural Health Monitoring

    Directory of Open Access Journals (Sweden)

    John Reilly


    Full Text Available Temperature changes play a large role in the day to day structural behavior of structures, but a smaller direct role in most contemporary Structural Health Monitoring (SHM analyses. Temperature-Driven SHM will consider temperature as the principal driving force in SHM, relating a measurable input temperature to measurable output generalized strain (strain, curvature, etc. and generalized displacement (deflection, rotation, etc. to create three-dimensional signatures descriptive of the structural behavior. Identifying time periods of minimal thermal gradient provides the foundation for the formulation of the temperature–deformation–displacement model. Thermal gradients in a structure can cause curvature in multiple directions, as well as non-linear strain and stress distributions within the cross-sections, which significantly complicates data analysis and interpretation, distorts the signatures, and may lead to unreliable conclusions regarding structural behavior and condition. These adverse effects can be minimized if the signatures are evaluated at times when thermal gradients in the structure are minimal. This paper proposes two classes of methods based on the following two metrics: (i the range of raw temperatures on the structure, and (ii the distribution of the local thermal gradients, for identifying time periods of minimal thermal gradient on a structure with the ability to vary the tolerance of acceptable thermal gradients. The methods are tested and validated with data collected from the Streicker Bridge on campus at Princeton University.

  10. Identifying Time Periods of Minimal Thermal Gradient for Temperature-Driven Structural Health Monitoring. (United States)

    Reilly, John; Glisic, Branko


    Temperature changes play a large role in the day to day structural behavior of structures, but a smaller direct role in most contemporary Structural Health Monitoring (SHM) analyses. Temperature-Driven SHM will consider temperature as the principal driving force in SHM, relating a measurable input temperature to measurable output generalized strain (strain, curvature, etc.) and generalized displacement (deflection, rotation, etc.) to create three-dimensional signatures descriptive of the structural behavior. Identifying time periods of minimal thermal gradient provides the foundation for the formulation of the temperature-deformation-displacement model. Thermal gradients in a structure can cause curvature in multiple directions, as well as non-linear strain and stress distributions within the cross-sections, which significantly complicates data analysis and interpretation, distorts the signatures, and may lead to unreliable conclusions regarding structural behavior and condition. These adverse effects can be minimized if the signatures are evaluated at times when thermal gradients in the structure are minimal. This paper proposes two classes of methods based on the following two metrics: (i) the range of raw temperatures on the structure, and (ii) the distribution of the local thermal gradients, for identifying time periods of minimal thermal gradient on a structure with the ability to vary the tolerance of acceptable thermal gradients. The methods are tested and validated with data collected from the Streicker Bridge on campus at Princeton University.

  11. Variation of Time Domain Failure Probabilities of Jack-up with Wave Return Periods (United States)

    Idris, Ahmad; Harahap, Indra S. H.; Ali, Montassir Osman Ahmed


    This study evaluated failure probabilities of jack up units on the framework of time dependent reliability analysis using uncertainty from different sea states representing different return period of the design wave. Surface elevation for each sea state was represented by Karhunen-Loeve expansion method using the eigenfunctions of prolate spheroidal wave functions in order to obtain the wave load. The stochastic wave load was propagated on a simplified jack up model developed in commercial software to obtain the structural response due to the wave loading. Analysis of the stochastic response to determine the failure probability in excessive deck displacement in the framework of time dependent reliability analysis was performed by developing Matlab codes in a personal computer. Results from the study indicated that the failure probability increases with increase in the severity of the sea state representing a longer return period. Although the results obtained are in agreement with the results of a study of similar jack up model using time independent method at higher values of maximum allowable deck displacement, it is in contrast at lower values of the criteria where the study reported that failure probability decreases with increase in the severity of the sea state.

  12. Multiple Time Series Forecasting Using Quasi-Randomized Functional Link Neural Networks

    Directory of Open Access Journals (Sweden)

    Thierry Moudiki


    Full Text Available We are interested in obtaining forecasts for multiple time series, by taking into account the potential nonlinear relationships between their observations. For this purpose, we use a specific type of regression model on an augmented dataset of lagged time series. Our model is inspired by dynamic regression models (Pankratz 2012, with the response variable’s lags included as predictors, and is known as Random Vector Functional Link (RVFL neural networks. The RVFL neural networks have been successfully applied in the past, to solving regression and classification problems. The novelty of our approach is to apply an RVFL model to multivariate time series, under two separate regularization constraints on the regression parameters.

  13. Summary of the CDFE nuclear data activity for 2011 - 2012 period of time, Progress report

    International Nuclear Information System (INIS)

    Varlamov, V.V.; Komarov, S.Yu.; Peskov, N.N.; Stepanov, M.E.


    This report contains the short review of the main fields of nuclear data activity of the Centre for Photonuclear Experiments Data (Centr Dannykh Fotoyadernykh Eksperimentov - CDFE) of Skobeltsyn Institute of Nuclear Physics of Lomonosov Moscow State University and main results obtained. All works were carried out in close co-operation with the Nuclear Science Section in the frame of the IAEA Nuclear Reaction Data Centres Network for the period of time from the IAEA Technical Meeting on the International Network of Nuclear Reaction Data Centers' (23 - 24 May 2011, IAEA, Vienna, Austria) till the spring of 2012. (author)

  14. The Iterative Solution to Discrete-Time H∞ Control Problems for Periodic Systems

    Directory of Open Access Journals (Sweden)

    Ivan G. Ivanov


    Full Text Available This paper addresses the problem of solving discrete-time H ∞ control problems for periodic systems. The approach for solving such a type of equations is well known in the literature. However, the focus of our research is set on the numerical computation of the stabilizing solution. In particular, two effective methods for practical realization of the known iterative processes are described. Furthermore, a new iterative approach is investigated and applied. On the basis of numerical experiments, we compare the presented methods. A major conclusion is that the new iterative approach is faster than rest of the methods and it uses less RAM memory than other methods.

  15. Dynamical stability for finite quantum spin chains against a time-periodic inhomogeneous perturbation

    International Nuclear Information System (INIS)

    Kudo, Kazue; Nakamura, Katsuhiro


    We investigate dynamical stability of the ground state against a time-periodic and spatially-inhomogeneous magnetic field for finite quantum XXZ spin chains. We use the survival probability as a measure of stability and demonstrate that it decays as P(t) ∝ t -1/2 under a certain condition. The dynamical properties should also be related to the level statistics of the XXZ spin chains with a constant spatially-inhomogeneous magnetic field. The level statistics depends on the anisotropy parameter and the field strength. We show how the survival probability depends on the anisotropy parameter, the strength and frequency of the field.

  16. A seesaw in Mediterranean precipitation during the Roman Period linked to millennial-scale changes in the North Atlantic

    NARCIS (Netherlands)

    Dermody, B.; Boer, H.J. de; Bierkens, M.F.P.; Weber, S.L.; Wassen, M.J.; Dekker, S.C.


    We present a reconstruction of the change in climatic humidity around the Mediterranean between 3000– 1000 yr BP. Using a range of proxy archives and model simulations we demonstrate that climate during this period was typified by a millennial-scale seesaw in climatic humidity between Spain and

  17. Linking Time and Space Scales in Distributed Hydrological Modelling - a case study for the VIC model (United States)

    Melsen, Lieke; Teuling, Adriaan; Torfs, Paul; Zappa, Massimiliano; Mizukami, Naoki; Clark, Martyn; Uijlenhoet, Remko


    One of the famous paradoxes of the Greek philosopher Zeno of Elea (~450 BC) is the one with the arrow: If one shoots an arrow, and cuts its motion into such small time steps that at every step the arrow is standing still, the arrow is motionless, because a concatenation of non-moving parts does not create motion. Nowadays, this reasoning can be refuted easily, because we know that motion is a change in space over time, which thus by definition depends on both time and space. If one disregards time by cutting it into infinite small steps, motion is also excluded. This example shows that time and space are linked and therefore hard to evaluate separately. As hydrologists we want to understand and predict the motion of water, which means we have to look both in space and in time. In hydrological models we can account for space by using spatially explicit models. With increasing computational power and increased data availability from e.g. satellites, it has become easier to apply models at a higher spatial resolution. Increasing the resolution of hydrological models is also labelled as one of the 'Grand Challenges' in hydrology by Wood et al. (2011) and Bierkens et al. (2014), who call for global modelling at hyperresolution (~1 km and smaller). A literature survey on 242 peer-viewed articles in which the Variable Infiltration Capacity (VIC) model was used, showed that the spatial resolution at which the model is applied has decreased over the past 17 years: From 0.5 to 2 degrees when the model was just developed, to 1/8 and even 1/32 degree nowadays. On the other hand the literature survey showed that the time step at which the model is calibrated and/or validated remained the same over the last 17 years; mainly daily or monthly. Klemeš (1983) stresses the fact that space and time scales are connected, and therefore downscaling the spatial scale would also imply downscaling of the temporal scale. Is it worth the effort of downscaling your model from 1 degree to 1

  18. Time series modelling of increased soil temperature anomalies during long period (United States)

    Shirvani, Amin; Moradi, Farzad; Moosavi, Ali Akbar


    Soil temperature just beneath the soil surface is highly dynamic and has a direct impact on plant seed germination and is probably the most distinct and recognisable factor governing emergence. Autoregressive integrated moving average as a stochastic model was developed to predict the weekly soil temperature anomalies at 10 cm depth, one of the most important soil parameters. The weekly soil temperature anomalies for the periods of January1986-December 2011 and January 2012-December 2013 were taken into consideration to construct and test autoregressive integrated moving average models. The proposed model autoregressive integrated moving average (2,1,1) had a minimum value of Akaike information criterion and its estimated coefficients were different from zero at 5% significance level. The prediction of the weekly soil temperature anomalies during the test period using this proposed model indicated a high correlation coefficient between the observed and predicted data - that was 0.99 for lead time 1 week. Linear trend analysis indicated that the soil temperature anomalies warmed up significantly by 1.8°C during the period of 1986-2011.

  19. Detection of Quasi-Periodic Pulsations in Solar EUV Time Series (United States)

    Dominique, M.; Zhukov, A. N.; Dolla, L.; Inglis, A.; Lapenta, G.


    Quasi-periodic pulsations (QPPs) are intrinsically connected to the mechanism of solar flares. They are regularly observed in the impulsive phase of flares since the 1970s. In the past years, the studies of QPPs regained interest with the advent of a new generation of soft X-ray/extreme ultraviolet radiometers that pave the way for statistical surveys. Since the amplitude of QPPs in these wavelengths is rather small, detecting them implies that the overall trend of the time series needs to be removed before applying any Fourier or wavelet transform. This detrending process is known to produce artificial detection of periods that must then be distinguished from real ones. In this paper, we propose a set of criteria to help identify real periods and discard artifacts. We apply these criteria to data taken by the Extreme Ultraviolet Variability Experiment (EVE)/ESP onboard the Solar Dynamics Observatory (SDO) and the Large Yield Radiometer (LYRA) onboard the PRoject for On-Board Autonomy 2 (PROBA2) to search for QPPs in flares stronger than M5.0 that occurred during Solar Cycle 24.

  20. Prompt-period measurement of the Annular Core Research Reactor prompt neutron generation time

    International Nuclear Information System (INIS)

    Coats, R.L.; Talley, D.G.; Trowbridge, F.R.


    The prompt neutron generation time for the Annular Core Research Reactor was experimentally determined using a prompt-period technique. The resultant value of 25.5 μs agreed well with the analytically determined value of 24 μs. The three different methods of reactivity insertion determination yielded ±5% agreement in the experimental values of the prompt neutron generation time. Discrepancies observed in reactivity insertion values determined by the three methods used (transient rod position, relative delayed critical control rod positions, and relative transient rod and control rod positions) were investigated to a limited extent. Rod-shadowing and low power fuel/coolant heat-up were addressed as possible causes of the discrepancies

  1. Rapid Acquisition of Choice and Timing and the Provenance of the Terminal-Link Effect (United States)

    Kyonka, Elizabeth G. E.; Grace, Randolph C.


    Eight pigeons responded in a concurrent-chains procedure in which terminal-link schedules changed pseudorandomly across sessions. Pairs of terminal-link delays either summed to 15 s or to 45 s. Across sessions, the location of the shorter terminal link changed according to a pseudorandom binary sequence. On some terminal links, food was withheld…

  2. Evaluation of cytotoxicity and degree of conversion of orthodontic adhesives over different time periods

    Directory of Open Access Journals (Sweden)

    Matheus Melo Pithon


    Full Text Available As new orthodontic resin adhesives continue to be marketed, rapid and sensitive tests for examining their toxic effects at the ' cell and tissue level ' are needed because patient safety has been identifi ed as a legal concept. The objective of the present study was to evaluate the cytotoxicity and degree of monomer conversion of orthodontic adhesives over different time periods. Seven adhesives: Transbond® XT, Transbond® Color Change, Quick Cure, EagleBond, Orthobond®, Fill Mágic® and Biofix® were evaluated for their cytotoxicity in L929 fibroblastic cells and for their degree of monomer conversion over different time periods. Three control groups were also analysed: Positive control (C+, consisting of Tween 80 cell detergent; Negative control (C-, consisting of PBS; and cell control (CC, consisting of cells exposed to any material. The dye-uptake technique that involves the absorption of a neutral red dye in viable cells was used for the cytotoxicity evaluation and the degree of conversion was evaluated using spectroscopy with infrared. The results showed the cytotoxicity of the adhesives at 24, 48, 72 and 168 hours. At these times, the viability values presented for these materials were statistically different from the groups CC and C- (p 0.05. In the monomer conversions there was a percentage increase of monomer conversion from 24 to 72 hours. A direct correlation could be observed between cytotoxicity and monomer conversions. From this work it can be concluded that all adhesives evaluated are cytotoxic at the times of 24, 48 and 72 hours. Monomers continued conversion even after photopolymerization had stopped.

  3. Motives for early retirement of self-employed GPs in the Netherlands: a comparison of two time periods.

    NARCIS (Netherlands)

    Greuningen, M. van; Heiligers, P.J.M.; Velden, L.F.J. van der


    Background: The high cost of training and the relatively long period of training for physicians make it beneficial to stimulate physicians to retire later. Therefore, a better understanding of the link between the factors influencing the decision to retire and actual turnover would benefit policies

  4. Understanding the Link Between Pubertal Timing in Girls and the Development of Depressive Symptoms: The Role of Sexual Harassment. (United States)

    Skoog, Therése; Bayram Özdemir, Sevgi; Stattin, Håkan


    The link between sexual maturation, or pubertal timing, in girls and adolescent depressive symptoms is well-documented, but the underlying processes remain unclear. We examined whether sexual harassment, which has previously been linked to both pubertal timing and depressive symptoms, mediates this link, using a two-wave longitudinal study including 454 girls in 7th (M age  = 13.42, SD = .53) and 8th grade (M age  = 14.42, SD = .55). Pubertal timing was linked to depressive symptoms in both age groups, and predicted an increase in depressive symptoms among the 7th graders. Sexual harassment significantly mediated the link between pubertal timing and depressive symptoms among the 7th, but not the 8th grade girls. Together, our findings suggest that one way to prevent depressive symptoms among early-maturing girls could be to address sexual harassment in preventive intervention in early adolescence.

  5. Prediction of in-service time period of three differently stabilized single base propellants

    Energy Technology Data Exchange (ETDEWEB)

    Bohn, Manfred A. [Fraunhofer-Institut fuer Chemische Technologie (ICT), Pfinztal-Berghausen (Germany)


    Three nitrocellulose-based propellants for use in micro gas generators equipped with different stabilizing systems have been investigated to assess the stabilization capability with regard to in-service time, whereby strong time-temperature profiles have been applied. The three stabilizing systems have been (i) 0.74 mass-% diphenylamine (DPA) and 0.48 mass-% Akardite II (Ak II); (ii) 1.25 mass-% Ak II; (iii) 2.04 mass-% Ak II. Several profiles were considered. Two simulate the heating at sun exposure in hot areas, others consider environmental temperatures in hot-humid and hot-dry areas. They were evaluated according to the load and finally one was chosen for the assessment. The contents of stabilizers were determined by high performance liquid chromatography after Soxhlet type extraction. To describe stabilizer consumption, the most suitable kinetic model was taken. Therewith a prediction was made using the chosen time-temperature profile named 'Phoenix', designed for temperatures at the steering wheel. The objective was to reach with this profile 15 years until the consumption of primary stabilizer content. This is conservative, because with the stabilizing action of the consecutive products of the stabilizers longer times are possible. (Abstract Copyright [2009], Wiley Periodicals, Inc.)

  6. Evolution of illustrations in anatomy: a study from the classical period in Europe to modern times. (United States)

    Ghosh, Sanjib Kumar


    Illustrations constitute an essential element of learning anatomy in modern times. However it required a significant evolutionary process spread over centuries, for illustrations to achieve the present status in the subject of anatomy. This review article attempts to outline the evolutionary process by highlighting on the works of esteemed anatomists in a chronological manner. Available literature suggests that illustrations were not used in anatomy during the classical period when the subject was dominated by the descriptive text of Galen. Guido da Vigevano was first to use illustrations in anatomy during the Late Middle Ages and this concept developed further during the Renaissance period when Andreas Vesalius pioneered in illustrations becoming an indispensable tool in conveying anatomical details. Toward later stages of the Renaissance period, Fabricius ab Aquapendente endeavored to restrict dramatization of anatomical illustrations which was a prevalent trend in early Renaissance. During the 18th century, anatomical artwork was characterized by the individual styles of prominent anatomists leading to suppression of anatomical details. In the 19th century, Henry Gray used illustrations in his anatomical masterpiece that focused on depicting anatomical structures and were free from any artistic style. From early part of the 20th century medical images and photographs started to complement traditional handmade anatomical illustrations. Computer technology and advanced software systems played a key role in the evolution of anatomical illustrations during the late 20th century resulting in new generation 3D image datasets that are being used in the 21st century in innovative formats for teaching and learning anatomy. © 2014 American Association of Anatomists.

  7. Cross-Linked Fluorescent Supramolecular Nanoparticles as Finite Tattoo Pigments with Controllable Intradermal Retention Times. (United States)

    Choi, Jin-Sil; Zhu, Yazhen; Li, Hongsheng; Peyda, Parham; Nguyen, Thuy Tien; Shen, Mo Yuan; Yang, Yang Michael; Zhu, Jingyi; Liu, Mei; Lee, Mandy M; Sun, Shih-Sheng; Yang, Yang; Yu, Hsiao-Hua; Chen, Kai; Chuang, Gary S; Tseng, Hsian-Rong


    Tattooing has been utilized by the medical community for precisely demarcating anatomic landmarks. This practice is especially important for identifying biopsy sites of nonmelanoma skin cancer (NMSC) due to the long interval (i.e., up to 3 months) between the initial diagnostic biopsy and surgical treatment. Commercially available tattoo pigments possess several issues, which include causing poor cosmesis, being mistaken for a melanocytic lesion, requiring additional removal procedures when no longer desired, and potentially inducing inflammatory responses. The ideal tattoo pigment for labeling of skin biopsy sites for NMSC requires (i) invisibility under ambient light, (ii) fluorescence under a selective light source, (iii) a finite intradermal retention time (ca. 3 months), and (iv) biocompatibility. Herein, we introduce cross-linked fluorescent supramolecular nanoparticles (c-FSNPs) as a "finite tattoo" pigment, with optimized photophysical properties and intradermal retention time to achieve successful in vivo finite tattooing. Fluorescent supramolecular nanoparticles encapsulate a fluorescent conjugated polymer, poly[5-methoxy-2-(3-sulfopropoxy)-1,4-phenylenevinylene] (MPS-PPV), into a core via a supramolecular synthetic approach. FSNPs which possess fluorescent properties superior to those of the free MPS-PPV are obtained through a combinatorial screening process. Covalent cross-linking of FSNPs results in micrometer-sized c-FSNPs, which exhibit a size-dependent intradermal retention. The 1456 nm sized c-FSNPs display an ideal intradermal retention time (ca. 3 months) for NMSC lesion labeling, as observed in an in vivo tattoo study. In addition, the c-FSNPs induce undetectable inflammatory responses after tattooing. We believe that the c-FSNPs can serve as a "finite tattoo" pigment to label potential malignant NMSC lesions.

  8. Development of potential map for landslides by comparing instability indices of various time periods (United States)

    Chiang, Jie-Lun; Tian, Yu-Qing; Chen, Yie-Ruey; Tsai, Kuang-Jung


    In recent years, extreme rainfall events occur frequently and induced serious landslides and debris flow disasters in Taiwan. The instability indices will differ when using landslide maps of different time periods. We analyzed the landslide records during the period year, 2008 2012, the landslide area contributed 0.42% 2.94% of the total watershed area, the 2.94% was caused by the typhoon Morakot in August, 2009, which brought massive rainfall in which the cumulative maximum rainfall was up to 2900 mm. We analyzed the instability factors including elevation, slope, aspect, soil, and geology. And comparing the instability indices by using individual landslide map of 2008 2012, the landslide maps of the union of the five years, and interaction of the five years. The landslide area from union of the five years contributed 3.71%,the landslide area from interaction of the five years contributed 0.14%. In this study, Kriging was used to establish the susceptibility map in selected watershed. From interaction of the five years, we found the instability index above 4.3 can correspond to those landslide records. The potential landslide area of the selected watershed, where collapses occur more likely, belongs to high level and medium-high level; the area is 13.43% and 3.04% respectively.

  9. Dynamical generalized Hurst exponent as a tool to monitor unstable periods in financial time series (United States)

    Morales, Raffaello; Di Matteo, T.; Gramatica, Ruggero; Aste, Tomaso


    We investigate the use of the Hurst exponent, dynamically computed over a weighted moving time-window, to evaluate the level of stability/instability of financial firms. Financial firms bailed-out as a consequence of the 2007-2008 credit crisis show a neat increase with time of the generalized Hurst exponent in the period preceding the unfolding of the crisis. Conversely, firms belonging to other market sectors, which suffered the least throughout the crisis, show opposite behaviors. We find that the multifractality of the bailed-out firms increase at the crisis suggesting that the multi fractal properties of the time series are changing. These findings suggest the possibility of using the scaling behavior as a tool to track the level of stability of a firm. In this paper, we introduce a method to compute the generalized Hurst exponent which assigns larger weights to more recent events with respect to older ones. In this way large fluctuations in the remote past are less likely to influence the recent past. We also investigate the scaling associated with the tails of the log-returns distributions and compare this scaling with the scaling associated with the Hurst exponent, observing that the processes underlying the price dynamics of these firms are truly multi-scaling.

  10. Motor and linguistic linking of space and time in the cerebellum. (United States)

    Oliveri, Massimiliano; Bonnì, Sonia; Turriziani, Patrizia; Koch, Giacomo; Lo Gerfo, Emanuele; Torriero, Sara; Vicario, Carmelo Mario; Petrosini, Laura; Caltagirone, Carlo


    Recent literature documented the presence of spatial-temporal interactions in the human brain. The aim of the present study was to verify whether representation of past and future is also mapped onto spatial representations and whether the cerebellum may be a neural substrate for linking space and time in the linguistic domain. We asked whether processing of the tense of a verb is influenced by the space where response takes place and by the semantics of the verb. Responses to past tense were facilitated in the left space while responses to future tense were facilitated in the right space. Repetitive transcranial magnetic stimulation (rTMS) of the right cerebellum selectively slowed down responses to future tense of action verbs; rTMS of both cerebellar hemispheres decreased accuracy of responses to past tense in the left space and to future tense in the right space for non-verbs, and to future tense in the right space for state verbs. The results suggest that representation of past and future is mapped onto spatial formats and that motor action could represent the link between spatial and temporal dimensions. Right cerebellar, left motor brain networks could be part of the prospective brain, whose primary function is to use past experiences to anticipate future events. Both cerebellar hemispheres could play a role in establishing the grammatical rules for verb conjugation.

  11. Periodic input of dust over the Eastern Carpathians during the Holocene linked with Saharan desertification and human impact (United States)

    Longman, Jack; Veres, Daniel; Ersek, Vasile; Salzmann, Ulrich; Hubay, Katalin; Bormann, Marc; Wennrich, Volker; Schäbitz, Frank


    Reconstructions of dust flux have been used to produce valuable global records of changes in atmospheric circulation and aridity. These studies have highlighted the importance of atmospheric dust in marine and terrestrial biogeochemistry and nutrient cycling. By investigating a 10 800-year-long paleoclimate archive from the Eastern Carpathians (Romania) we present the first peat record of changing dust deposition over the Holocene for the Carpathian-Balkan region. Using qualitative (X-ray fluorescence (XRF) core scanning) and quantitative inductively coupled plasma optical emission spectrometer(ICP-OES) measurements of lithogenic (K, Si, Ti) elements, we identify 10 periods of major dust deposition between 9500-9200, 8400-8100, 7720-7250, 6350-5950, 5450-5050, 4130-3770, 3450-2850, 2000-1450, 800-620, and 60 cal yr BP to present. In addition, we used testate amoeba assemblages preserved within the peat to infer local palaeohydroclimatic conditions. Our record highlights several discrepancies between eastern and western European dust depositional records and the impact of highly complex hydrological regimes in the Carpathian region. Since 6100 cal yr BP, we find that the geochemical indicators of dust flux have become uncoupled from the local hydrology. This coincides with the appearance of millennial-scale cycles in the dust input and changes in geochemical composition of dust. We suggest that this is indicative of a shift in dust provenance from local-regional (likely loess-related) to distal (Saharan) sources, which coincide with the end of the African Humid Period and the onset of Saharan desertification.

  12. Generation of a quantum integrable class of discrete-time or relativistic periodic Toda chains

    International Nuclear Information System (INIS)

    Kundu, Anjan


    A new integrable class of quantum models representing a family of different discrete-time or relativistic generalisations of the periodic Toda chain (TC), including that of a recently proposed classical model close to TC [Lett. Math. Phys. 29 (1993) 165] is presented. All such models are shown to be obtainable from a single ancestor model at different realisations of the underlying quantised algebra. As a consequence the 2x2 Lax operators and the associated quantum R-matrices for these models are easily derived ensuring their quantum integrability. It is shown that the functional Bethe ansatz developed for the quantum TC is trivially generalised to achieve separation of variables also for the present models. ((orig.))

  13. Hydromagnetic natural convection flow between vertical parallel plates with time-periodic boundary conditions

    International Nuclear Information System (INIS)

    Adesanya, S.O.; Oluwadare, E.O.; Falade, J.A.; Makinde, O.D.


    In this paper, the free convective flow of magnetohydrodynamic fluid through a channel with time periodic boundary condition is investigated by taking the effects of Joule dissipation into consideration. Based on simplifying assumptions, the coupled governing equations are reduced to a set of nonlinear boundary valued problem. Approximate solutions are obtained by using semi-analytical Adomian decomposition method. The effect of pertinent parameters on the fluid velocity, temperature distribution, Nusselt number and skin friction are presented graphically and discussed. The result of the computation shows that an increase in the magnetic field intensity has significant influence on the fluid flow. - Highlights: • The influence of magnetic field on the free convective fluid flow is considered. • The coupled equations are solved by using Adomian decomposition method. • The Adomian series solution agreed with previously obtained result. • Magnetic field decreases the velocity maximum but enhances temperature field

  14. Multiple periodic solutions for a discrete time model of plankton allelopathy


    Zhang Jianbao; Fang Hui


    We study a discrete time model of the growth of two species of plankton with competitive and allelopathic effects on each other N1(k+1) = N1(k)exp{r1(k)-a11(k)N1(k)-a12(k)N2(k)-b1(k)N1(k)N2(k)}, N2(k+1) = N2(k)exp{r2(k)-a21(k)N2(k)-b2(k)N1(k)N1(k)N2(k)}. A set of sufficient conditions is obtained for the existence of multiple positive periodic solutions for this model. The approach is based on Mawhin's continuation theorem of coincidence degree theory as well as some a priori estimates. Some...

  15. Removing tidal-period variations from time-series data using low-pass digital filters (United States)

    Walters, Roy A.; Heston, Cynthia


    Several low-pass, digital filters are examined for their ability to remove tidal Period Variations from a time-series of water surface elevation for San Francisco Bay. The most efficient filter is the one which is applied to the Fourier coefficients of the transformed data, and the filtered data recovered through an inverse transform. The ability of the filters to remove the tidal components increased in the following order: 1) cosine-Lanczos filter, 2) cosine-Lanczos squared filter; 3) Godin filter; and 4) a transform fitter. The Godin fitter is not sufficiently sharp to prevent severe attenuation of 2–3 day variations in surface elevation resulting from weather events.

  16. Crossing rule for a PT-symmetric two-level time-periodic system

    International Nuclear Information System (INIS)

    Moiseyev, Nimrod


    For a two-level system in a time-periodic field we show that in the non-Hermitian PT case the level crossing is of two quasistationary states that have the same dynamical symmetry property. At the field's parameters where the two levels which have the same dynamical symmetry cross, the corresponding quasienergy states coalesce and a self-orthogonal state is obtained. This situation is very different from the Hermitian case where a crossing of two quasienergy levels happens only when the corresponding two quasistationary states have different dynamical symmetry properties and, unlike the situation in the non-Hermitian case, the spectrum remains complete also when the two levels cross.

  17. Influence of the harvesting time, temperature and drying period on basil (Ocimum basilicum L. essential oil

    Directory of Open Access Journals (Sweden)

    José Luiz S. Carvalho Filho

    Full Text Available Ocimum basilicum L. essential oil with high concentration of linalool is valuable in international business. O. basilicum essential oil is widely used as seasoning and in cosmetic industry. To assure proper essential oil yield and quality, it is crucial to determine which environmental and processing factors are affecting its composition. The goal of our work is to evaluate the effects of harvesting time, temperature, and drying period on the yield and chemical composition of O. basilicum essential oil. Harvestings were performed 40 and 93 days after seedling transplantation. Harvesting performed at 8:00 h and 12:00 h provided higher essential oil yield. After five days drying, the concentration of linalool raised from 45.18% to 86.80%. O. basilicum should be harvested during morning and the biomass dried at 40ºC for five days to obtain linalool rich essential oil.

  18. Links Between Education and Age at Marriage among Palestinian Women in Israel: Changes Over Time. (United States)

    Sabbah-Karkaby, Maha; Stier, Haya


    This study focuses on the link between education and marriage timing among Israeli-Palestinian women. Theoretical discussions on marriage timing center on the effect of the time women spend in educational institutions on their age at marriage, and on the change in the desirable traits of women in the marriage market. But most of these arguments overlook situations where significant changes in education take place alongside retention of traditional patriarchal values. Based on data from three population censuses - in 1983, 1995 and 2008-our results suggest that staying longer in schooling delays marriage, so women with less education are more likely to marry earlier than others. While young age is still considered an important characteristic in the Israeli-Palestinian marriage market, and women who delay marriage face a greater risk of remaining single, education becomes more important over the years so that postponing marriage becomes especially problematic for low-educated women. Our findings suggest that traditional norms and structural conditions together shape marriage timing. © 2017 The Population Council, Inc.

  19. Investigation of the effects of time periodic pressure and engpotential gradients on viscoelastic fluid flow in circular narrow confinements

    DEFF Research Database (Denmark)

    Nguyen, Trieu; van der Meer, Devaraj; van den Berg, Albert


    -Boltzmann equation, together with the incompressible Cauchy momentum equation under no-slip boundary conditions for viscoelastic fluid in the case of a combination of time periodic pressure-driven and electro-osmotic flow. The resulting solutions allow us to predict the electrical current and solution flow rate...... conversion applications. We also found that time periodic electro-osmotic flow in many cases is much stronger enhanced than time periodic pressure-driven flow when comparing the flow profiles of oscillating PDF and EOF in micro-and nanochannels. The findings advance our understanding of time periodic......In this paper we present an in-depth analysis and analytical solution for time periodic hydrodynamic flow (driven by a time-dependent pressure gradient and electric field) of viscoelastic fluid through cylindrical micro-and nanochannels. Particularly, we solve the linearized Poisson...

  20. Links between sex-typed time use in middle childhood and gender development in early adolescence. (United States)

    McHale, Susan M; Kim, Ji-Yeon; Whiteman, Shawn; Crouter, Ann C


    The authors studied sex-typing in the kinds (e.g., sports, handicrafts) and social contexts (same- vs. other-sex companions) of children's free time activities, and the links between sex-typed activities and gender development over 2 years. Participants were 200 White, working- and middle-class children (103 girls, 97 boys; mean age = 10.86 years). In annual home interviews, children rated their self-esteem, gender role attitudes and sex-typed personality qualities, academic interests, and school grades. During 7 nightly phone interviews each year, children reported on their activities. Boys were more sex-typed than girls in their peer activities, and children were least sex-typed in their activities with siblings. Sex-typed activities in middle childhood predicted individual differences in gender development in early adolescence. Copyright 2004 American Psychological Association

  1. Time trends, improvements and national auditing of rectal cancer management over an 18-year period. (United States)

    Kodeda, K; Johansson, R; Zar, N; Birgisson, H; Dahlberg, M; Skullman, S; Lindmark, G; Glimelius, B; Påhlman, L; Martling, A


    The main aims were to explore time trends in the management and outcome of patients with rectal cancer in a national cohort and to evaluate the possible impact of national auditing on overall outcomes. A secondary aim was to provide population-based data for appraisal of external validity in selected patient series. Data from the Swedish ColoRectal Cancer Registry with virtually complete national coverage were utilized in this cohort study on 29 925 patients with rectal cancer diagnosed between 1995 and 2012. Of eligible patients, nine were excluded. During the study period, overall, relative and disease-free survival increased. Postoperative mortality after 30 and 90 days decreased to 1.7% and 2.9%. The 5-year local recurrence rate dropped to 5.0%. Resection margins improved, as did peri-operative blood loss despite more multivisceral resections being performed. Fewer patients underwent palliative resection and the proportion of non-operated patients increased. The proportions of temporary and permanent stoma formation increased. Preoperative radiotherapy and chemoradiotherapy became more common as did multidisciplinary team conferences. Variability in rectal cancer management between healthcare regions diminished over time when new aspects of patient care were audited. There have been substantial changes over time in the management of patients with rectal cancer, reflected in improved outcome. Much indirect evidence indicates that auditing matters, but without a control group it is not possible to draw firm conclusions regarding the possible impact of a quality control registry on faster shifts in time trends, decreased variability and improvements. Registry data were made available for reference. Colorectal Disease © 2015 The Association of Coloproctology of Great Britain and Ireland.

  2. Periodic fluctuations in correlation-based connectivity density time series: Application to wind speed-monitoring network in Switzerland (United States)

    Laib, Mohamed; Telesca, Luciano; Kanevski, Mikhail


    In this paper, we study the periodic fluctuations of connectivity density time series of a wind speed-monitoring network in Switzerland. By using the correlogram-based robust periodogram annual periodic oscillations were found in the correlation-based network. The intensity of such annual periodic oscillations is larger for lower correlation thresholds and smaller for higher. The annual periodicity in the connectivity density seems reasonably consistent with the seasonal meteo-climatic cycle.

  3. Hydrometeorological aspects of the Real-Time Ultrafinescale Forecast Support during the Special Observing Period of the MAP*

    Directory of Open Access Journals (Sweden)

    R. Benoit


    Full Text Available During the Special Observation Period (SOP, 7 September–15 November, 1999 of the Mesoscale Alpine Programme (MAP, the Canadian Mesoscale Compressible Community Model (MC2 was run in real time at a horizontal resolution of 3 km on a computational domain of 350☓300☓50 grid points, covering the whole of the Alpine region. The WATFLOOD model was passively coupled to the MC2; the former is an integrated set of computer programs to forecast flood flows, using all available data, for catchments with response times ranging from one hour to several weeks. The unique aspect of this contribution is the operational application of numerical weather prediction data to forecast flows over a very large, multinational domain. An overview of the system performance from the hydrometeorological aspect is presented, mostly for the real-time results, but also from subsequent analyses. A streamflow validation of the precipitation is included for large basins covering upper parts of the Rhine and the Rhone, and parts of the Po and of the Danube. In general, the MC2/WATFLOOD model underestimated the total runoff because of the under-prediction of precipitation by MC2 during the MAP SOP. After the field experiment, a coding error in the cloud microphysics scheme of MC2 explains this underestimation to a large extent. A sensitivity study revealed that the simulated flows reproduce the major features of the observed flow record for most of the flow stations. The experiment was considered successful because two out of three possible flood events in the Swiss-Italian border region were predicted correctly by data from the numerical weather models linked to the hydrological model and no flow events were missed. This study has demonstrated that a flow forecast from a coupled atmospheric-hydrological model can serve as a useful first alert and quantitative forecast. Keywords: mesoscale atmospheric model, hydrological model, flood forecasting, Alps

  4. Radiation exposure of ventilated trauma patients in intensive care: a retrospective study comparing two time periods. (United States)

    Yee, Micaela V; Barron, Rochelle A; Knobloch, Tom A; Pandey, Umesh; Twyford, Catherine; Freebairn, Ross C


    To describe the cumulative effective dose of radiation that was received during the initial Emergency Department assessment and ICU stay of patients admitted with trauma, who required mechanical ventilation, during two time periods. A retrospective analysis of radiological and clinical data, set in a regional nonurban ICU. Two cohorts (starting 1 January 2004 and 1 January 2009), each comprising 45 adult patients admitted with trauma who were mechanically ventilated in intensive care, were studied. Frequency and type of radiological examinations, demographic information, and clinical data were collated from the radiological database, hospital admission record and Australian Outcomes Research Tool for Intensive Care database. Cumulative effective doses were calculated and expressed as a total dose and average daily dose for each cohort. The median cumulative effective dose per patient (in milliSieverts) increased from 34.59 [interquartile range (IQR) 9.08-43.91] in 2004 to 40.51 (IQR 22.01-48.87) in 2009, P=0.045. An increased number of computed tomography examinations per patient was also observed over the same interval from an average of 2.11 (median 2, IQR 1-3) in 2004 to an average of 2.62 (2, 2-4) in 2009, P=0.046. The radiation exposure of mechanically ventilated trauma patients in intensive care has increased over time. Radiation exposure should be prospectively monitored and staff should be aware of the increased risk resulting from this change in practice.

  5. Acute effect of different time periods of passive static stretching on the hamstring flexibility. (United States)

    Cini, Anelize; de Vasconcelos, Gabriela Souza; Lima, Claudia Silveira


    Several factors are associated with the presence of chronic low back pain; one of them is the flexibility of the hamstring muscles that influences the posture of the pelvic spine. Investigate the influence of two different time periods of passive static stretching on the flexibility of the hamstring. Forty-six physiotherapy students were divided into two groups performing stretching exercises: 30 s and 60 s duration. The collections consisted of: (1) pre-test: evaluation of the flexibility of the hip and knee, using a manual goniometer by means of the following tests: Straight Leg Raise Test (SLR), Passive Hip Flexion Test (PHFT) and Modified Knee Extension Test (MKET), (2) intervention: stretching with different runtimes, (3) post-test: reappraisal of flexibility, conducted immediately after the intervention. Significant difference was observed intra groups, group that did stretching exercises lasting 30 seconds (G30) (SLR p = 0.000. PHFT p = 0.003 and MKET p = 0.000) and group that did stretching exercises lasting 60 seconds (G60) (SLR p = 0.000. PHFT p = 0.001 and MKET p = 0.002). Comparing the groups, no significant difference was found (SLR p = 0.307; PHFT p = 0.904; MKET p = 0.132). Thus it can be inferred that 30 seconds are sufficient for increased flexibility of young women. Therefore the time-treatment sessions can be optimized. Only the acute effect of stretching was observed; further investigation of the long-term effect is required.

  6. Estimating interevent time distributions from finite observation periods in communication networks (United States)

    Kivelä, Mikko; Porter, Mason A.


    A diverse variety of processes—including recurrent disease episodes, neuron firing, and communication patterns among humans—can be described using interevent time (IET) distributions. Many such processes are ongoing, although event sequences are only available during a finite observation window. Because the observation time window is more likely to begin or end during long IETs than during short ones, the analysis of such data is susceptible to a bias induced by the finite observation period. In this paper, we illustrate how this length bias is born and how it can be corrected without assuming any particular shape for the IET distribution. To do this, we model event sequences using stationary renewal processes, and we formulate simple heuristics for determining the severity of the bias. To illustrate our results, we focus on the example of empirical communication networks, which are temporal networks that are constructed from communication events. The IET distributions of such systems guide efforts to build models of human behavior, and the variance of IETs is very important for estimating the spreading rate of information in networks of temporal interactions. We analyze several well-known data sets from the literature, and we find that the resulting bias can lead to systematic underestimates of the variance in the IET distributions and that correcting for the bias can lead to qualitatively different results for the tails of the IET distributions.

  7. Relationships between rumination time, metabolic conditions, and health status in dairy cows during the transition period. (United States)

    Soriani, N; Trevisi, E; Calamari, L


    The main objective of this experiment was to monitor the rumination pattern during the transition period in primiparous (PR) and pluriparous (PL) dairy cows and to investigate its relationships with metabolic conditions, milk yield, and health status. The study was carried out in an experimental free-stall barn and involved 32 Italian Friesian cows (9 PR and 23 PL) during the transition phase. The rumination time (RT) was recorded with an automatic system (HR-Tag), and data were calculated and summarized in 2-h intervals. Blood samples were collected during the transition phase to assess biochemical variables related to energy, protein, and mineral metabolism, as well as markers of inflammatory conditions and some enzyme activity. Daily milk yield, BW, nutritional condition, and health status were also recorded. The average RT before calving (-20 to -6 d) was 463 min/d in PR (range 270 to 620) and 522 min/d in PL (range 411 to 640). In the early lactation [15 to 40 d in milk (DIM)], the average RT was 504 min/d in PR (range 400 to 585) and 562 min/d in PL (range 414 to 685) and was positively correlated with milk yield (r = 0.36; P Cows with reduced RT before calving maintained reduced RT after calving and suffered a greater frequency of disease than cows with greater RT in late pregnancy. Moreover, cows characterized by mild inflammatory conditions and without health disorders or only mild health disorders during the puerperium showed a greater average rumination time (over 520 min/d) during the first 10 d of lactation. Conversely, the decreased RT (450 min/d) during the first few days of lactation was observed in cows with subclinical diseases or health disorders. Cows affected by clinical mastitis during the trial showed a reduction of RT and a change in its variability already some days before the drug treatment. Our results suggest that the automatic measurement of RT is useful to predict calving time and to quickly obtain information on health status of the

  8. 40 CFR 80.305 - How are credits generated during the time period 2000 through 2003? (United States)


    ... averaging period. Va = Total volume of gasoline produced during the averaging period at the refinery (or for a foreign refinery, the total volume of gasoline produced during the averaging period at the... level, calculated in accordance with the provisions of § 80.205, for gasoline produced during the...

  9. Categorization of ber varieties in relation to blooming period, fruit setting and harvesting time

    International Nuclear Information System (INIS)

    Sharif, N.; Abbas, M.M.; Ishfaq, M.; Memon, N.U.N.


    Thirty four local Ber varieties were evaluated at Horticultural Research Institute AARI, Faisalabad, Horticultural Research Station Bahawalpur (Punjab) and Jujube Research Station, Tandojam (Sindh). Traits viz. total period of blooming (dates), peak period of blooming (dates), total period of fruit set (dates), peak period of fruit set (dates), total period of fruit harvest (dates), peak period of fruit harvest (dates), total flowering days, peak flowering days, total fruit setting days, peak fruit setting days, total harvesting days and peak harvesting days were studied. The results revealed significant differences in parameters studied except total period of blooming under Tandojam, Sindh conditions. Varieties were classified as early, mid and late season for both provinces. Local varieties had potential for further manipulation in terms of variety improvement to attract growers for extensive ber cultivations under changing global climatic scenario. (author)

  10. Linking the Timing of Career and Technical Education Coursetaking with High School Dropout and College-Going Behavior (United States)

    Gottfried, Michael A.; Plasman, Jay Stratte


    While prior studies have examined the efficacy of career and technical education (CTE) courses on high school students' outcomes, there is little knowledge on timing of these courses and a potential link to student outcomes. We asked if the timing of these courses predicted differences in the likelihood of dropout and on-time high school…

  11. The Chern-Simons current in time series of knots and links in proteins (United States)

    Capozziello, Salvatore; Pincak, Richard


    A superspace model of knots and links for DNA time series data is proposed to take into account the feedback loop from docking to undocking state of protein-protein interactions. In particular, the direction of interactions between the 8 hidden states of DNA is considered. It is a E8 ×E8 unified spin model where the genotype, from active and inactive side of DNA time data series, can be considered for any living organism. The mathematical model is borrowed from loop-quantum gravity and adapted to biology. It is used to derive equations for gene expression describing transitions from ground to excited states, and for the 8 coupling states between geneon and anti-geneon transposon and retrotransposon in trash DNA. Specifically, we adopt a modified Grothendieck cohomology and a modified Khovanov cohomology for biology. The result is a Chern-Simons current in (8 + 3) extradimensions of a given unoriented supermanifold with ghost fields of protein structures. The 8 dimensions come from the 8 hidden states of spinor field of genetic code. The extradimensions come from the 3 types of principle fiber bundle in the secondary protein.

  12. Estimating return periods of extreme values from relatively short time series of winds (United States)

    Jonasson, Kristjan; Agustsson, Halfdan; Rognvaldsson, Olafur; Arfeuille, Gilles


    An important factor for determining the prospect of individual wind farm sites is the frequency of extreme winds at hub height. Here, extreme winds are defined as the value of the highest 10 minutes averaged wind speed with a 50 year return period, i.e. annual exceeding probability of 2% (Rodrigo, 2010). A frequently applied method to estimate winds in the lowest few hundred meters above ground is to extrapolate observed 10-meter winds logarithmically to higher altitudes. Recent study by Drechsel et al. (2012) showed however that this methodology is not as accurate as interpolating simulated results from the global ECMWF numerical weather prediction (NWP) model to the desired height. Observations of persistent low level jets near Colima in SW-Mexico also show that the logarithmic approach can give highly inaccurate results for some regions (Arfeuille et al., 2012). To address these shortcomings of limited, and/or poorly representative, observations and extrapolations of winds one can use NWP models to dynamically scale down relatively coarse resolution atmospheric analysis. In the case of limited computing resources one has typically to make a compromise between spatial resolution and the duration of the simulated period, both of which can limit the quality of the wind farm siting. A common method to estimate maximum winds is to fit an extreme value distribution (e.g. Gumbel, gev or Pareto) to the maximum values of each year of available data, or the tail of these values. If data are only available for a short period, e.g. 10 or 15 years, then this will give a rather inaccurate estimate. It is possible to deal with this problem by utilizing monthly or weekly maxima, but this introduces new problems: seasonal variation, autocorrelation of neighboring values, and increased discrepancy between data and fitted distribution. We introduce a new method to estimate return periods of extreme values of winds at hub height from relatively short time series of winds, simulated

  13. [The effect of breast massage at different time in the early period after cesarean section]. (United States)

    Chu, J Y; Zhang, L; Zhang, Y J; Yang, M J; Li, X W; Sun, L L


    Objective: To evaluate the effect of breast massage at different time in the early period on maternal lactation after cesarean section. Methods: 80 women delivered by cesarean section were randomly selected from maternity ward of a hospital in Shandong province during Jan. 2013 to Jan. 2015; which were divided into four groups, with 20 patients in each. Three groups received 3 times of breast massage every 24 hoursbeginning from 2, 12 and 24 h after cesarean section, respectively. The control group didn't receive any breast massage. The starting time and status of lactation were observed and recorded after cesarean section. 5 ml venous blood sample was drawn from each patient respectively at 2 h before cesarean, 6, 12, 24, 48 and 72 h after cesarean to test the level of serum prolactin. The lactation status of each group was compared. Results: The P (50) ( P (25)- P (75)) of starting time of lactation of the three massage groups and control group were 3 (2-6) h, 4 (2-8) h, 4 (3-12) h and 4 (2-12) h, respectively, whose differences showed no statistical significance ( H =3.32, P= 0.345).The number of delivered women with adequate lactation 24 hours after cesarean was 10 in the group who received massage beginning from 2 h after cesarean; while the number was only 2 in the control group. The number of delivered women with adequate lactation 48 hours after cesarean was 18 in the group who received massage beginning from 2 h after cesarean; while the number was 8 in the control group. The differences showed statistical significances ( P values were 0.021 and 0.008, respectively). The serum prolactin level in the group of delivered women who received massage from 2 h after cesarean was separately (195.9±78.5), (176.0±96.5), (216.4±110.0), (190.0±56.8) and (184.8±69.6) μg/L at 2, 12, 24, 48 and 72 h after cesarean, which were significantly higher than those in the control group (which were (128.8±40.6), (127.3±66.8), (162.2±58.8), (145.1±64.7) and (141.7±49

  14. Generational and time period differences in American adolescents' religious orientation, 1966-2014.

    Directory of Open Access Journals (Sweden)

    Jean M Twenge

    Full Text Available In four large, nationally representative surveys (N = 11.2 million, American adolescents and emerging adults in the 2010s (Millennials were significantly less religious than previous generations (Boomers, Generation X at the same age. The data are from the Monitoring the Future studies of 12th graders (1976-2013, 8th and 10th graders (1991-2013, and the American Freshman survey of entering college students (1966-2014. Although the majority of adolescents and emerging adults are still religiously involved, twice as many 12th graders and college students, and 20%-40% more 8th and 10th graders, never attend religious services. Twice as many 12th graders and entering college students in the 2010s (vs. the 1960s-70s give their religious affiliation as "none," as do 40%-50% more 8th and 10th graders. Recent birth cohorts report less approval of religious organizations, are less likely to say that religion is important in their lives, report being less spiritual, and spend less time praying or meditating. Thus, declines in religious orientation reach beyond affiliation to religious participation and religiosity, suggesting a movement toward secularism among a growing minority. The declines are larger among girls, Whites, lower-SES individuals, and in the Northeastern U.S., very small among Blacks, and non-existent among political conservatives. Religious affiliation is lower in years with more income inequality, higher median family income, higher materialism, more positive self-views, and lower social support. Overall, these results suggest that the lower religious orientation of Millennials is due to time period or generation, and not to age.

  15. A simple derivation for amplitude and time period of charged particles in an electrostatic bathtub potential

    International Nuclear Information System (INIS)

    Prathap Reddy, K


    An ‘electrostatic bathtub potential’ is defined and analytical expressions for the time period and amplitude of charged particles in this potential are obtained and compared with simulations. These kinds of potentials are encountered in linear electrostatic ion traps, where the potential along the axis appears like a bathtub. Ion traps are used in basic physics research and mass spectrometry to store ions; these stored ions make oscillatory motion within the confined volume of the trap. Usually these traps are designed and studied using ion optical software, but in this work the bathtub potential is reproduced by making two simple modifications to the harmonic oscillator potential. The addition of a linear ‘ k 1 | x |’ potential makes the simple harmonic potential curve steeper with a sharper turn at the origin, while the introduction of a finite-length zero potential region at the centre reproduces the flat region of the bathtub curve. This whole exercise of modelling a practical experimental situation in terms of a well-known simple physics problem may generate interest among readers. (paper)

  16. Evaluating the efficiency of a zakat institution over a period of time using data envelopment analysis (United States)

    Krishnan, Anath Rau; Hamzah, Ahmad Aizuddin


    It is crucial for a zakat institution to evaluate and understand how efficiently they have operated in the past, thus ideal strategies could be developed for future improvement. However, evaluating the efficiency of a zakat institution is actually a challenging process as it involves the presence of multiple inputs or/and outputs. This paper proposes a step-by-step procedure comprising two data envelopment analysis models, namely dual Charnes-Cooper-Rhodes and slack-based model to quantitatively measure the overall efficiency of a zakat institution over a period of time. The applicability of the proposed procedure was demonstrated by evaluating the efficiency of Pusat Zakat Sabah, Malaysia from the year of 2007 up to 2015 by treating each year as a decision making unit. Two inputs (i.e. number of staff and number of branches) and two outputs (i.e. total collection and total distribution) were used to measure the overall efficiency achieved each year. The causes of inefficiency and strategy for future improvement were discussed based on the results.

  17. Homicides with direct and indirect links to the night-time economy. (United States)

    Tomsen, Stephen


    Alcohol use and homicide are a wide community concern with particular interest in understanding and preventing attacks (e.g. 'one punch' male on male attacks) in commercial nightlife settings with high levels of collective drinking. There is insufficient knowledge of the long-term patterns in this violence or the relationship between public drinking and flow on violence in other social settings. Alcohol-related homicides were those in which alcohol consumption was a contributing factor. Those also linked to purchase or consumption in locations where alcohol is sold after dark were classified as night-time economy related. The study comprised a first-hand analysis of files in the archive of the Australian National Homicide Monitoring Program in 2 years with a decade gap (1998/1999-2007/2008), and it classified 73 of all 238 alcohol-related incidents by direct or indirect relation to public nightlife settings. Related homicides in these years were not highly concentrated in developed night-time economies, but more spread outside major nightlife zones. Indirectly related killings were even more dispersed and included more women victims killed in domestic settings. There is a consistent though dispersed relationship between heavy public drinking at night and homicide. Concerns about homicide and night-time drinking leisure with mostly male victims attacked in well-known areas of busy city nightlife, must also consider the broader gendered patterns of 'flow on' nightlife-related incidents, including fatal semi-private and domestic violence that is indirectly but importantly related to drinking and alcohol purchase in public commercial nightlife. © 2018 Australasian Professional Society on Alcohol and other Drugs.

  18. Typical Periods for Two-Stage Synthesis by Time-Series Aggregation with Bounded Error in Objective Function

    Energy Technology Data Exchange (ETDEWEB)

    Bahl, Björn; Söhler, Theo; Hennen, Maike; Bardow, André, E-mail: [Institute of Technical Thermodynamics, RWTH Aachen University, Aachen (Germany)


    Two-stage synthesis problems simultaneously consider here-and-now decisions (e.g., optimal investment) and wait-and-see decisions (e.g., optimal operation). The optimal synthesis of energy systems reveals such a two-stage character. The synthesis of energy systems involves multiple large time series such as energy demands and energy prices. Since problem size increases with the size of the time series, synthesis of energy systems leads to complex optimization problems. To reduce the problem size without loosing solution quality, we propose a method for time-series aggregation to identify typical periods. Typical periods retain the chronology of time steps, which enables modeling of energy systems, e.g., with storage units or start-up cost. The aim of the proposed method is to obtain few typical periods with few time steps per period, while accurately representing the objective function of the full time series, e.g., cost. Thus, we determine the error of time-series aggregation as the cost difference between operating the optimal design for the aggregated time series and for the full time series. Thereby, we rigorously bound the maximum performance loss of the optimal energy system design. In an initial step, the proposed method identifies the best length of typical periods by autocorrelation analysis. Subsequently, an adaptive procedure determines aggregated typical periods employing the clustering algorithm k-medoids, which groups similar periods into clusters and selects one representative period per cluster. Moreover, the number of time steps per period is aggregated by a novel clustering algorithm maintaining chronology of the time steps in the periods. The method is iteratively repeated until the error falls below a threshold value. A case study based on a real-world synthesis problem of an energy system shows that time-series aggregation from 8,760 time steps to 2 typical periods with each 2 time steps results in an error smaller than the optimality gap of

  19. Time-scale calibration by U-Pb geochronology: Examples from the Triassic Period (United States)

    Mundil, R.


    U-Pb zircon geochronology, pioneered by Tom Krogh, is a cornerstone for the calibration of the time scale. Before Krogh's innovations, U-Pb geochronology was essentially limited by laboratory blank Pb (typically hundreds of nanograms) inherent in the then existing zircon dissolution and purification methods. The introduction of high pressure HF dissolution combined with miniature ion exchange columns (1) reduced the blank by orders of magnitude and allowed mass-spectrometric analyses of minute amounts of material (picograms of Pb and U). Krogh also recognized the need for minimizing the effects of Pb loss, and the introduction of the air-abrasion technique was the method of choice for two decades (2), until the development of the combined annealing and chemical abrasion technique resulted in essentially closed system zircons (3). These are the prerequisite for obtaining precise (permil-level) and accurate radio-isotopic ages of individual zircons contained in primary volcanic ash deposits, which are primary targets for the calibration of the time scale if they occur within fossil bearing sediments. A prime example is the calibration of the Triassic time scale which improved significantly using these techniques. The ages for the base and the top of the Triassic are constrained by U-Pb ages to 252.3 (4) and 201.5 Ma (5), respectively. These dates also constrain the ages of major extinction events at the Permian-Triassic and Triassic-Jurassic boundaries, and are statistically indistinguishable from ages obtained for the Siberian Traps and volcanic products from the Central Atlantic Magmatic Province, respectively, suggesting a causal link. Ages for these continental volcanics, however, are mostly from the K-Ar (40Ar/39Ar) system which requires accounting and correcting for a systematic bias of ca 1 % between U-Pb and 40Ar/39Ar isotopic ages (the 40Ar/39Ar ages being younger) (6). Robust U-Pb age constraints also exist for the Induan- Olenekian boundary (251.2 Ma, (7

  20. Feedback effect of human physical and psychological adaption on time period of thermal adaption in naturally ventilated building

    DEFF Research Database (Denmark)

    liu, weiwei; Huangfu, Hao; Xiong, Jing


    This study proposed a method to determine time period of thermal adaption for occupants in naturally ventilated building, and analyzed the synergistic and separate feedback effect of the physical and psychological adaption modes on the time period of thermal adaption. Using the method, the values...... of the time period of thermal adaption were obtained on the basis of the data from a long-term field survey conducted in two typical naturally ventilated offices located in Changsha, China. The results showed that the occupants need to take 4.25 days to fully adapt to a step-change in outdoor air temperature...

  1. Role of aging and hippocampus in Time-Place Learning: link to episodic-like memory?

    Directory of Open Access Journals (Sweden)

    Cornelis Kees Mulder


    Full Text Available Introduction: with time-place learning (TPL, animals link an event with the spatial location and the time of day. The what-where-when TPL components make the task putatively episodic-like in nature. Animals use an internal sense of time to master TPL, which is circadian system based. Finding indications for a role of the hippocampus and (early aging-sensitivity in TPL would strengthen the episodic-like memory nature of the paradigm. Methods: previously, we used C57Bl/6 mice for our TPL research. Here, we used CD1 mice which are less hippocampal-driven and age faster compared to C57Bl/6 mice. To demonstrate the low degree of hippocampal-driven performance in CD1 mice, a cross maze was used. The spontaneous alternation test was used to score spatial working memory in CD1 mice at four different age categories (young (3-6 months, middle-aged (7-11 months, aged (12-18 months and old (>19 months. TPL performance of middle-aged and aged CD1 mice was tested in a setup with either two or three time points per day (2-arm or 3-arm TPL task. Immunostainings was applied on brains of young and middle-aged C57Bl/6 mice that had successfully mastered the 3-arm TPL task. Results: in contrast to C57Bl/6 mice, middle-aged and aged CD1 mice were less hippocampus-driven and failed to master the 3-arm TPL task. They could, however, master the 2-arm TPL task primarily via an ordinal (non-circadian timing system. c-Fos, CRY2, vasopressin (AVP, and pCREB were investigated. We found no differences at the level of the suprachiasmatic nucleus (SCN; circadian master clock, whereas CRY2 expression was increased in the hippocampal dentate gyrus. The most pronounced difference between TPL trained and control mice was found in c-Fos expression in the paraventricular thalamic nucleus, a circadian system relay station. Conclusions: These results further indicate a key role of CRY proteins in TPL and confirm the limited role of the SCN in TPL. Based on the poor TPL performance of

  2. Out of time: a possible link between mirror neurons, autism and electromagnetic radiation. (United States)

    Thornton, Ian M


    Recent evidence suggests a link between autism and the human mirror neuron system. In this paper, I argue that temporal disruption from the environment may play an important role in the observed mirror neuron dysfunction, leading in turn to the pattern of deficits associated with autism. I suggest that the developing nervous system of an infant may be particularly prone to temporal noise that can interfere with the initial calibration of brain networks such as the mirror neuron system. The most likely source of temporal noise in the environment is artificially generated electromagnetic radiation. To date, there has been little evidence that electromagnetic radiation poses a direct biological hazard. It is clear, however, that time-varying electromagnetic waves have the potential to temporally modulate the nervous system, particularly when populations of neurons are required to act together. This modulation may be completely harmless for the fully developed nervous system of an adult. For an infant, this same temporal disruption might act to severely delay or disrupt vital calibration processes.

  3. Two new fern chloroplasts and decelerated evolution linked to the long generation time in tree ferns. (United States)

    Zhong, Bojian; Fong, Richard; Collins, Lesley J; McLenachan, Patricia A; Penny, David


    We report the chloroplast genomes of a tree fern (Dicksonia squarrosa) and a "fern ally" (Tmesipteris elongata), and show that the phylogeny of early land plants is basically as expected, and the estimates of divergence time are largely unaffected after removing the fastest evolving sites. The tree fern shows the major reduction in the rate of evolution, and there has been a major slowdown in the rate of mutation in both families of tree ferns. We suggest that this is related to a generation time effect; if there is a long time period between generations, then this is probably incompatible with a high mutation rate because otherwise nearly every propagule would probably have several lethal mutations. This effect will be especially strong in organisms that have large numbers of cell divisions between generations. This shows the necessity of going beyond phylogeny and integrating its study with other properties of organisms. © The Author(s) 2014. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  4. Parasitism of The Rice Brown Planthopper Eggs in Various Periods of Time of The Day

    Directory of Open Access Journals (Sweden)

    Siti Haryati


    Full Text Available The rice brown planthopper, Nilaparvata lugens (Hemiptera: Delphacidae is an important pest of rice. Since at the early stage, this pest is infested by parasitoids, but most cultural practices do not consider the existences of parasitoids in rice ecosystem. This study was aimed to determine the level of parasitism on N. lugens with regard to the time of the day. This information would be useful to minimize the effect of insecticide application to the parasitoids. Trapping  of  egg parasitoids in rice ecosystem was conducted every two hours from 05.00 a.m. until 04.00 p.m. Parasitism occured as early as at 05.00 a.m. (12.26% of the total parasitoid found, reached the peak abundance at 11.00 a.m. (36.13%, and decreased at 01.00 p.m. The parasitism level varied from 1.12 to 8.51% at 66 days after planting. The highest number of parasitoids and the highest parasitism level occured when trapping was conducted between 11.00 a.m.−01.00 p.m.. Before and after this period of time, the number of parasitoid emerged and parasitism were low. This suggest that if insecticide is necessary, it should be applied in the early morning or late afternoon.   INTISARI Wereng batang padi cokelat, Nilaparvata lugens (Hemiptera: Delphacidae, merupakan salah satu hama penting padi. Praktik budidaya pertanian padi belum memperhatikan aktivitas parasitoid dalam ekosistem. Tujuan dari penelitian ini yaitu untuk mengetahui tingkat parasitasi telur N. lugens pada beberapa waktu dalam sehari. Informasi ini akan bermanfaat untuk mengurangi dampak aplikasi insektisida terhadap parasitoid. Pemerangkapan parasitoid telur N. lugens di lahan padi dilakukan setiap dua jam yang dimulai pada pukul 05.00 sampai pukul 16.00. Parasitoid telur N. lugens mulai aktif pada pukul 05.00 (12,26%, mencapai puncaknya pukul 11.00 (36,13%, dan mulai mengalami penurunan pada pukul 13.00. Tingkat parasitasi pada tanaman padi umur 66 hari setelah tanam berkisar mulai 1,12−8,51%. Hasil

  5. Global Exponential Stability of Positive Almost Periodic Solutions for a Fishing Model with a Time-Varying Delay

    Directory of Open Access Journals (Sweden)

    Hong Zhang


    Full Text Available This paper is concerned with a nonautonomous fishing model with a time-varying delay. Under proper conditions, we employ a novel argument to establish a criterion on the global exponential stability of positive almost periodic solutions of the model with almost periodic coefficients and delays. Moreover, an example and its numerical simulation are given to illustrate the main results.

  6. On scattering diagnostics with periodically pulsed lasers to follow the continuous evolution of time dependent plasma parameters

    International Nuclear Information System (INIS)

    Hellermann, M. von; Hirsch, K.; Doeble, H.F.


    The possibilities to use periodically pulsed lasers for plasma scattering diagnostics are discussed. An experiment with succesful application of a periodically pulsed frequency-doubled Nd:YAG laser is described and results are given. Application of the method to monitor continuously, with millisecond time resolution, parameters of Tokamak type plasmas, is considered. (orig.) [de

  7. Optimal base-stock policy for the inventory system with periodic review, backorders and sequential lead times

    DEFF Research Database (Denmark)

    Johansen, Søren Glud; Thorstenson, Anders


    We extend well-known formulae for the optimal base stock of the inventory system with continuous review and constant lead time to the case with periodic review and stochastic, sequential lead times. Our extension uses the notion of the 'extended lead time'. The derived performance measures...

  8. Magnetic cycles and rotation periods of late-type stars from photometric time series (United States)

    Suárez Mascareño, A.; Rebolo, R.; González Hernández, J. I.


    Aims: We investigate the photometric modulation induced by magnetic activity cycles and study the relationship between rotation period and activity cycle(s) in late-type (FGKM) stars. Methods: We analysed light curves, spanning up to nine years, of 125 nearby stars provided by the All Sky Automated Survey (ASAS). The sample is mainly composed of low-activity, main-sequence late-A to mid-M-type stars. We performed a search for short (days) and long-term (years) periodic variations in the photometry. We modelled the light curves with combinations of sinusoids to measure the properties of these periodic signals. To provide a better statistical interpretation of our results, we complement our new results with results from previous similar works. Results: We have been able to measure long-term photometric cycles of 47 stars, out of which 39 have been derived with false alarm probabilities (FAP) of less than 0.1 per cent. Rotational modulation was also detected and rotational periods were measured in 36 stars. For 28 stars we have simultaneous measurements of activity cycles and rotational periods, 17 of which are M-type stars. We measured both photometric amplitudes and periods from sinusoidal fits. The measured cycle periods range from 2 to 14 yr with photometric amplitudes in the range of 5-20 mmag. We found that the distribution of cycle lengths for the different spectral types is similar, as the mean cycle is 9.5 yr for F-type stars, 6.7 yr for G-type stars, 8.5 yr for K-type stars, 6.0 yr for early M-type stars, and 7.1 yr for mid-M-type stars. On the other hand, the distribution of rotation periods is completely different, trending to longer periods for later type stars, from a mean rotation of 8.6 days for F-type stars to 85.4 days in mid-M-type stars. The amplitudes induced by magnetic cycles and rotation show a clear correlation. A trend of photometric amplitudes with rotation period is also outlined in the data. The amplitudes of the photometric variability

  9. Delay-Dependent Stability Criteria of Uncertain Periodic Switched Recurrent Neural Networks with Time-Varying Delays

    Directory of Open Access Journals (Sweden)

    Xing Yin


    uncertain periodic switched recurrent neural networks with time-varying delays. When uncertain discrete-time recurrent neural network is a periodic system, it is expressed as switched neural network for the finite switching state. Based on the switched quadratic Lyapunov functional approach (SQLF and free-weighting matrix approach (FWM, some linear matrix inequality criteria are found to guarantee the delay-dependent asymptotical stability of these systems. Two examples illustrate the exactness of the proposed criteria.

  10. Landing periodicity of the mosquito Aedes aegypti in Trinidad in relation to the timing of insecticidal space-spraying. (United States)

    Chadee, D D


    Diel landing periodicity (biting cycle) of domestic Aedes aegypti (L.) in Trinidad, West Indies, was monitored using human bait during January-August 1980. The periodicity of females was predominantly diurnal (95.2% arriving during daylight or twilight) and bimodal, with consistent peaks at 06.00-07.00 and 17.00-18.00 hours. The diel periodicities at indoor and outdoor sites were virtually identical. Larger numbers of adults were collected outside than inside houses. It is recommended that the time of insecticidal ULV adulticiding should coincide with peaks in landing periodicity of the Ae.aegypti adults.

  11. Links between personality, time perspective, and intention to practice physical activity during cancer treatment: an exploratory study. (United States)

    Villaron, Charlène; Marqueste, Tanguy; Eisinger, François; Cappiello, Maria-Antonietta; Therme, Pierre; Cury, François


    The purpose of the study was to analyze links between personality, time perspective, and intention to practice physical activity during cancer treatment. One hundred forty-three patients participated in survey by questionnaire. Intention to practice physical activity, time perspective using Zimbardo Time Perspective Inventory, and personality with the Big Five Inventory were measured. Structural equation models using Lisrel were developed to examine hypothetical links between the variables. The adjusted model evidenced an excellent fit (comparative fit index = 0.92; root-mean-square error of approximation = 0.076; P = .014). Results showed that intention to practice exercise was positively linked with openness to experience and negatively with present fatalist time perspective. Moreover, conscientiousness and neuroticism were found to be linked with future time perspective, which was positively related with intention to practice physical activity. The present exploratory study with patients suffering from cancer underlined the importance of considering jointly time perspective dimensions and personality factors for health behavior recommendations. Based on our results, we propose some reflections on practice to help nurses and physicians increase patient's motivation to be physically active. Taking into account patients' personality and time perspective, we would be able to propose specific awareness messages and offer short interventions to have an impact on patients' motivation to practice. Copyright © 2016 John Wiley & Sons, Ltd.

  12. Changes in the American Interventional Radiology Literature: Comparison over a 10-Year Time Period

    International Nuclear Information System (INIS)

    Ray, Charles E.; Gupta, Rajan; Blackwell, John


    Purpose. To determine the changes that occurred regarding interventional radiologic research in the major American radiology journals between 1992-1993 and 2002-2003. Methods. Articles published in three major American radiology journals (Journal of Vascular and Interventional Radiology, American Journal of Roentgenology, and Radiology) during two distinct 24-month time periods (1992-1993 and 2002-2003) were evaluated. All articles judged to be pertinent to the interventional radiologic community were included. Investigations included in journal subheadings other than 'interventional' or 'vascular radiology' were included if the emphasis of the article was on a vascular imaging modality or peripheral intervention. Exclusions included: case reports, technical reports, letters to the editor, breast interventions, and primary neurointerventions. Data were collected regarding the affiliations of the primary author (nationality, hospital type, department); primary category of interest of the investigation; funding information; and study design variables. Two-by-two chi-squared statistical analyses were performed comparing the variables from the early and late data sets. Results. A total of 405 articles met the inclusion criteria for the early data set (1992-1993); 488 articles met the inclusion criteria for the late data set (2002-2003). Variables that demonstrated a statistically significant decrease from the early data set to the late data set included: articles in which the primary author was from a department of radiology (91.1% vs. 86.3%; p < 0.025); articles written by a primary author who was American (69.4% vs. 44.6%; p < 0.001); and articles with a primary category of investigation that had a nonvascular intervention focus (22.7% vs. 11.9%; p < 0.001). Variables that demonstrated a statistically significant increase from the early data set to the late data set included primary authors from Western Europe (18.0% vs. 30.1%; p < 0.001) and Asia (6.6% vs. 18.4%; p

  13. The calculation of collective energies from periodic time-dependent Hartree-Fock solutions

    International Nuclear Information System (INIS)

    Zahed, I.; Baranger, M.


    A periodic TDHF solution is used as the reference state for a diagrammatic expansion of the propagator. A discrete Fourier transform leads to a function of energy, whose poles are the corresponding energy levels. Limiting the expansion to first-order diagrams leads to a new derivation of the Bohr-Sommerfeld-like quantization rule for collective states

  14. Note: Optimal base-stock policy for the inventory system with periodic review, backorders and sequential lead times

    DEFF Research Database (Denmark)

    Johansen, Søren Glud; Thorstenson, Anders

    We show that well-known textbook formulae for determining the optimal base stock of the inventory system with continuous review and constant lead time can easily be extended to the case with periodic review and stochastic, sequential lead times. The provided performance measures and conditions...

  15. Time domain phenomena of wave propagation in rapidly created plasma of periodic distribution

    International Nuclear Information System (INIS)

    Kuo, S P


    Theories, experiments and numerical simulations on the interaction of electromagnetic waves with rapidly created unmagnetized plasmas are presented. In the case that plasma is created uniformly, the frequency of a propagating electromagnetic wave is upshifted. An opposite propagation wave of the same frequency is also generated. In addition, a static current supporting a wiggler magnetic field is also produced in the plasma. When a spatially periodic structure is introduced to the rapidly created plasma, the theory and numerical simulation results show that both frequency-upshifted and downshifted waves are generated. If the plasma has a large but finite dimension in the incident wave propagation direction and is created rapidly rather than instantaneously, the frequency downshifted waves are found to be trapped by the plasma when the plasma frequency is larger than the wave frequency. The wave trapping results in accumulating the frequency-downshifted waves during the finite transient period of plasma creation. Indeed, in the experimental observations the frequency downshifted signals were detected repetitively with considerably enhanced spectral intensities, confirming the results of the numerical simulations. The missing of frequency upshifted signals in the experimental observations is explained by the modal field distributions in the periodic structure, indicating that the frequency upshifted modes experience heavier collisional damping of the plasma than the frequency downshifted modes

  16. Confidence in Phase Definition for Periodicity in Genes Expression Time Series. (United States)

    El Anbari, Mohammed; Fadda, Abeer; Ptitsyn, Andrey


    Circadian oscillation in baseline gene expression plays an important role in the regulation of multiple cellular processes. Most of the knowledge of circadian gene expression is based on studies measuring gene expression over time. Our ability to dissect molecular events in time is determined by the sampling frequency of such experiments. However, the real peaks of gene activity can be at any time on or between the time points at which samples are collected. Thus, some genes with a peak activity near the observation point have their phase of oscillation detected with better precision then those which peak between observation time points. Separating genes for which we can confidently identify peak activity from ambiguous genes can improve the analysis of time series gene expression. In this study we propose a new statistical method to quantify the phase confidence of circadian genes. The numerical performance of the proposed method has been tested using three real gene expression data sets.

  17. On the automation of periodic hard real-time processes: a graph-theoretical approach


    Boode, Antoon Hendrik


    Summary In certain single-core mono-processor configurations, e.g. embedded control systems like robotic applications comprising many short processes, process context switches may consume a considerable amount of the available processing power. Reducing the number of context switches decreases the execution time and thereby increases the performance of the application. Furthermore, the end-to-end processing time suffers from the idle time of the processor, because, for example, processes have...

  18. Exploring Mediating and Moderating Influences on the Links between Cycle Time, Proficiency in Entry Timing and New Product Profitability

    NARCIS (Netherlands)

    Langerak, F.; Hultink, E.J.; Griffin, A.


    Development cycle time is the elapsed time from the beginning of idea generation to the moment that the new product is ready for market introduction. Market entry timing is contingent upon the new product’s cycle time. Only when the product is completed can a firm decide whether and when to enter

  19. Automatic content linking: Speech-based just-in-time retrieval for multimedia archives

    NARCIS (Netherlands)

    Popescu-Belis, A.; Kilgour, J.; Poller, P.; Nanchen, A.; Boertjes, E.; Wit, J. de


    The Automatic Content Linking Device monitors a conversation and uses automatically recognized words to retrieve documents that are of potential use to the participants. The document set includes project related reports or emails, transcribed snippets of past meetings, and websites. Retrieval

  20. An analysis of periodic solutions of bi-directional associative memory networks with time-varying delays

    International Nuclear Information System (INIS)

    Cao Jinde; Jiang Qiuhao


    In this Letter, several sufficient conditions are derived for the existence and uniqueness of periodic oscillatory solution for bi-directional associative memory (BAM) networks with time-varying delays by employing a new Lyapunov functional and an elementary inequality, and all other solutions of the BAM networks converge exponentially to the unique periodic solution. These criteria are presented in terms of system parameters and have important leading significance in the design and applications of periodic neural circuits for delayed BAM. As an illustration, two numerical examples are worked out using the results obtained

  1. Stability of Almost Periodic Solution for a General Class of Discontinuous Neural Networks with Mixed Time-Varying Delays

    Directory of Open Access Journals (Sweden)

    Yingwei Li


    Full Text Available The global exponential stability issues are considered for almost periodic solution of the neural networks with mixed time-varying delays and discontinuous neuron activations. Some sufficient conditions for the existence, uniqueness, and global exponential stability of almost periodic solution are achieved in terms of certain linear matrix inequalities (LMIs, by applying differential inclusions theory, matrix inequality analysis technique, and generalized Lyapunov functional approach. In addition, the existence and asymptotically almost periodic behavior of the solution of the neural networks are also investigated under the framework of the solution in the sense of Filippov. Two simulation examples are given to illustrate the validity of the theoretical results.

  2. Framing Health Messages for Adolescents: Should We Use Objective Time Periods, Temporal Benchmarks, or Both? (United States)

    McKay, Michael T.; Cole, Jon C.; Sumnall, Harry R.; Goudie, Andrew J.


    Time perspective is a cognitive-motivational construct, which has been shown to be related to decision-making, motivation and adjustment. The majority of research into time perspective has been conducted in college students and/or general population samples. Focus groups were held as part of a larger investigation into the relationship between…

  3. Advantages and Drawbacks of Applying Periodic Time-Variant Modal Analysis to Spur Gear Dynamics

    DEFF Research Database (Denmark)

    Pedersen, Rune; Santos, Ilmar; Hede, Ivan Arthur


    to ensure sufficient accuracy of the results. The method of time-variant modal analysis is applied, and the changes in the fundamental and the parametric resonance frequencies as a function of the rotational speed of the gears, are found. By obtaining the stationary and parametric parts of the time...... of applying the methodology to wind turbine gearboxes are addressed and elucidated....

  4. Decay heat measurement of 235U in the time period from 10 to 1000 seconds

    International Nuclear Information System (INIS)

    Baumung, K.


    During the report period, the experimental facility was installed at the FR2 reactor. A delay was caused by the fact, that the supplying with water for the cooling loop of the pneumatic transfer system as well as discharge of exhaust gas into the halogeneventilation system of the reactor could not be performed as planned before. Therefore a cooling system was provided and tested and the efficiency of special halogene filters belonging to the experimental facility was verified. Now the apparatus is assembled and first cold tests have been performed. (orig.) [de

  5. Existence and global exponential stability of periodic solutions for n-dimensional neutral dynamic equations on time scales. (United States)

    Li, Bing; Li, Yongkun; Zhang, Xuemei


    In this paper, by using the existence of the exponential dichotomy of linear dynamic equations on time scales and the theory of calculus on time scales, we study the existence and global exponential stability of periodic solutions for a class of n-dimensional neutral dynamic equations on time scales. We also present an example to illustrate the feasibility of our results. The results of this paper are completely new and complementary to the previously known results even in both the case of differential equations (time scale [Formula: see text]) and the case of difference equations (time scale [Formula: see text]).

  6. A delay time model for a mission-based system subject to periodic and random inspection and postponed replacement

    International Nuclear Information System (INIS)

    Yang, Li; Ma, Xiaobing; Zhai, Qingqing; Zhao, Yu


    We propose an inspection and replacement policy for a single component system that successively executes missions with random durations. The failure process of the system can be divided into two states, namely, normal and defective, following the delay time concept. Inspections are carried out periodically and immediately after the completion of each mission (random inspections). The failed state is always identified immediately, whereas the defective state can only be revealed by an inspection. If the system fails or is defective at a periodic inspection, then replacement is immediate. If, however, the system is defective at a random inspection, then replacement will be postponed if the time to the subsequent periodic inspection is shorter than a pre-determined threshold, and immediate otherwise. We derive the long run expected cost per unit time and then investigate the optimal periodic inspection interval and postponement threshold. A numerical example is presented to demonstrate the applicability of the proposed maintenance policy. - Highlights: • A delay time model of inspection is introduced for mission-based systems. • Periodic and random inspections are performed to check the state. • Replacement of the defective system at a random inspection can be postponed.

  7. Growth and nutritional status of preschool children in India: a study of two recent time periods. (United States)

    Sen, Pronab; Bharati, Susmita; Som, Suparna; Pal, Manoranjan; Bharati, Premananda


    Preschool children call for focused attention in India because India has the highest percentage of undernourished children in the world. To compare the growth and nutritional status of Indian preschool children for the periods 1998/99 and 2005/06, Using data on weight and length/height as well as the sociodemographic background of preschool children from the National Family Health Surveys (NFHS) from 1998/99 and 2005/06, we determined the distribution of weight and length/height and their association with sociodemographic variables. The distributions of weight and length/height around the mean remained remarkably stable over age but were much greater in India than the international norms. The rates of growth of mean weight and length/ height were far lower in India than the international norms up to the age of 2 years. The temporal trend indicates declines in the percentages of undernourished (low weight-for-age) and stunted (low height-for-age) children over the 7-year period, although the degree of improvement was far better for stunting than for underweight. Mother's educational status is the only variable that has been found to influence child nutrition. The level of mothers' education needs urgent attention with top priority to reduce the prevalence of underweight and stunting of children. This also implies that, for future benefit, girls should be given more facilities for better education. Breastfeeding and weaning practices also need special attention.

  8. Full-Time versus Part-Time Employees: Understanding the Links between Work Status, the Psychological Contract, and Attitudes. (United States)

    Conway, Neil; Briner, Rob B.


    Analysis of psychological contract variables (affective and continuance commitment, intention to quit, well-being, job satisfaction, organizational citizenship behavior)was conducted on two samples: 1,608 banking employees (71% part time) and 366 supermarket employees (65% part time). Part- and full-time workers had different attitudes; fulfilment…

  9. A dynamical systems analysis of the kinematics of time-periodic vortex shedding past a circular cylinder (United States)

    Ottino, Julio M.


    Computer flow simulation aided by dynamical systems analysis is used to investigate the kinematics of time-periodic vortex shedding past a two-dimensional circular cylinder in the context of the following general questions: (1) Is a dynamical systems viewpoint useful in the understanding of this and similar problems involving time-periodic shedding behind bluff bodies; and (2) Is it indeed possible, by adopting such a point of view, to complement previous analyses or to understand kinematical aspects of the vortex shedding process that somehow remained hidden in previous approaches. We argue that the answers to these questions are positive. Results are described.

  10. The Perception of Time: Basic Research and Some Potential Links to the Study of Language (United States)

    Wearden, J. H.


    The article first discusses some recent work in time perception--in particular the distinction among prospective timing, retrospective timing, and passage of time judgments. The history and application of an "internal clock" model as an explanation of prospective timing performance is reviewed and contrasted with the different mechanisms needed…

  11. Measuring small time periods in earth sciences by uranium series disequilibrium

    International Nuclear Information System (INIS)

    Choudhary, A.K.


    During the last three decades mass spectrometry in India has seen its application in almost every field of science. In particular, TIMS has revolutionized geological sciences by taking it from a mainly descriptive to modern quantitative Earth Sciences. It has largely contributed in measurement of precise time scales of geological processes. During the last decade, focus has primarily been on measurement of time scales of these fundamental processes. Some of the radiometric methods initially developed for measuring shorter time-scales have their own problems. The intermediate nuclides in the uranium and thorium decay series having much shorter half lives compared to their parents, provide a useful tool to measure intermediate time scales. These isotopes had earlier been ignored due to analytical difficulties associated with their measurement. The development of new generation mass spectrometers with very high abundance sensitivity has now made it possible to measure these isotopic ratios. Consequently U-series isotopic measurements have put unique and at times the only quantitative constraints on the processes taking place in the interior of the Earth. Since such mass spectrometers have recently been installed in some of the laboratories in India, scientific investigation may now be taken up in some of the unexplored areas of Earth Sciences in our country

  12. Chinese wood frame buildings and the changing dimensions of their structural components in different time periods

    Directory of Open Access Journals (Sweden)

    Nujaba Binte Kabir


    Full Text Available The Features of the Chinese wood frame buildings are same in character from dynasty to dynasty. The study concentrates on 9 Chinese wood frame buildings from Tang to Yuan dynasty and tries to relate these buildings with the text described in a building manual book published in Song dynasty Yingzao fashi. The features of some buildings match with the text described in the book some do not. But on the other hand Liang Sicheng, scholar of Chinese architecture in his book claimed that Chinese wood frame architecture has a unique system of characteristics (Liang, 1984. The system of wood frame Chinese architecture did not change but the proportion of the features has changed in different dynasty. The aim of the paper is to compare the features of the buildings those have been studied according to Yingzao fashi with Liang's observation on the change of building style in different periods.

  13. Reply to 'Comment on 'Almost-periodic time observables for bound quantum systems''

    International Nuclear Information System (INIS)

    Hall, Michael J W


    In a recent paper (Hall 2008 J. Phys. A: Math. Gen. 41 255301), I made several critical remarks on a 'Hermitian time operator' proposed by Galapon (2002 Proc. R. Soc. A 458 2671). Galapon has correctly pointed out that remarks pertaining to 'denseness' of the commutator domain are wrong (Galapon 2008 J. Phys. A: Math. Theor. 42 018001). However, the other remarks still apply, and it is further noted that a given quantum system can be a member of this domain only at a set of times of total measure zero. (reply)

  14. Motives for early retirement of self-employed GPs in the Netherlands: a comparison of two time periods

    Directory of Open Access Journals (Sweden)

    Van Greuningen Malou


    Full Text Available Abstract Background The high cost of training and the relatively long period of training for physicians make it beneficial to stimulate physicians to retire later. Therefore, a better understanding of the link between the factors influencing the decision to retire and actual turnover would benefit policies designed to encourage later retirement. This study focuses on actual GP turnover and the determining factors for this in the Netherlands. The period 2003–2007 saw fewer GPs retiring from general practice than the period 1998–2002. In addition, GPs’ retirement age was higher in 2003–2007. For these two periods, we analysed work perception, objective workload and reasons for leaving, and related these with the probability that GPs would leave general practice at an early age. Methods In 2003, a first retrospective survey was sent to 520 self-employed GPs who had retired between 1998 and 2002. In 2008, the same survey was sent to 405 GPs who had retired between 2003 and 2007. The response rates were 60% and 54%, respectively. Analyses were done to compare work perception, objective workload, external factors and personal reasons for retiring. Results For both male and female GPs, work perception was different in the periods under scrutiny: both groups reported greater job satisfaction and a lower degree of emotional exhaustion in the later period, although there was no notable difference in subjective workload. The objective workload was lower in the second period. Moreover, most external factors and personal reasons that may contribute to the decision to retire were reported as less important in the second period. There was a stronger decrease in the probability that female GPs leave general practice within one year than for male GPs. This underscores the gender differences and the need for disaggregated data collection. Conclusions The results of this study suggest that the decrease in the probability of GPs leaving general practice

  15. Multi-Period Mean-Variance Portfolio Selection with Uncertain Time Horizon When Returns Are Serially Correlated

    Directory of Open Access Journals (Sweden)

    Ling Zhang


    Full Text Available We study a multi-period mean-variance portfolio selection problem with an uncertain time horizon and serial correlations. Firstly, we embed the nonseparable multi-period optimization problem into a separable quadratic optimization problem with uncertain exit time by employing the embedding technique of Li and Ng (2000. Then we convert the later into an optimization problem with deterministic exit time. Finally, using the dynamic programming approach, we explicitly derive the optimal strategy and the efficient frontier for the dynamic mean-variance optimization problem. A numerical example with AR(1 return process is also presented, which shows that both the uncertainty of exit time and the serial correlations of returns have significant impacts on the optimal strategy and the efficient frontier.

  16. Changes in Leisure-Time Physical Activity From the Prepregnancy to the Postpartum Period: 2004 Pelotas (Brazil) Birth Cohort Study. (United States)

    Coll, Carolina; Domingues, Marlos; Santos, Iná; Matijasevich, Alicia; Horta, Bernardo Lessa; Hallal, Pedro C


    The aim of this study was to evaluate changes in leisure-time physical activity (LTPA) and its correlates from prepregnancy to the postpartum period in mothers enrolled in a Brazilian birth cohort study. Our hypothesis was that LTPA would decline considerably during pregnancy. Maternal LTPA in the 3 months before pregnancy and during each trimester of pregnancy was assessed soon after delivery. A follow-up visit was conducted 3 months later. Weekly frequency and duration of each session of LTPA in a typical week were assessed for each period and a cut-off point of 150 minutes per week was used to classify women as active or not. The proportion of women active in leisure time declined from 11.3% in the prepregnancy to 2.3% in pregnancy and 0.1% in the postpartum period (P for trend benefits of LTPA prepregnancy, during, and postpregnancy.

  17. A study of mandibular fractures over a 5-year period of time: A retrospective study

    Directory of Open Access Journals (Sweden)

    Ashish Vyas


    Full Text Available Objective: This study aims to evaluate and compare with the existing literature on the etiology, pattern, gender, and anatomical distribution of mandibular fractures. Materials and Methods: The data of 225 cases were analyzed over a period of 5 years between March 2009 and November 2013. Of this 110 were unilateral, 23 bilateral, 18 symphysis and 74 multiple fractures. Results: Males are more affected than females.The peak incidence rate is occurring in 30-35 years of age group. The most common fracture site is parasymphysis and least common site is ramus of mandible. The most common etiological factor is road traffic accident (RTA (45.3% followed by falls (42.6%, assaults (8.9%, sport injuries (2.2%, and gunshot wounds (0.89%. Conclusion: Thus, we conclude that RTA is the leading cause of mandibular fractures and males are more affected. The most common site is parasymphysis fracture in association with angle fracture. We observed that gender was significantly associated with body and angle fracture (P = 0.04 and significant relationship between etiology with multiple site fracture such as (parasymphysis-angle, (body-condyle, (body-angle, and (symphysis-condyle was observed (P ≤ 0.05.

  18. The Inverse Contagion Problem (ICP) vs.. Predicting site contagion in real time, when network links are not observable (United States)

    Mushkin, I.; Solomon, S.


    We study the inverse contagion problem (ICP). As opposed to the direct contagion problem, in which the network structure is known and the question is when each node will be contaminated, in the inverse problem the links of the network are unknown but a sequence of contagion histories (the times when each node was contaminated) is observed. We consider two versions of the ICP: The strong problem (SICP), which is the reconstruction of the network and has been studied before, and the weak problem (WICP), which requires "only" the prediction (at each time step) of the nodes that will be contaminated at the next time step (this is often the real life situation in which a contagion is observed and predictions are made in real time). Moreover, our focus is on analyzing the increasing accuracy of the solution, as a function of the number of contagion histories already observed. For simplicity, we discuss the simplest (deterministic and synchronous) contagion dynamics and the simplest solution algorithm, which we have applied to different network types. The main result of this paper is that the complex problem of the convergence of the ICP for a network can be reduced to an individual property of pairs of nodes: the "false link difficulty". By definition, given a pair of unlinked nodes i and j, the difficulty of the false link (i,j) is the probability that in a random contagion history, the nodes i and j are not contaminated at the same time step (or at consecutive time steps). In other words, the "false link difficulty" of a non-existing network link is the probability that the observations during a random contagion history would not rule out that link. This probability is relatively straightforward to calculate, and in most instances relies only on the relative positions of the two nodes (i,j) and not on the entire network structure. We have observed the distribution of false link difficulty for various network types, estimated it theoretically and confronted it

  19. Spectral Analysis on Time-Course Expression Data: Detecting Periodic Genes Using a Real-Valued Iterative Adaptive Approach

    Directory of Open Access Journals (Sweden)

    Kwadwo S. Agyepong


    Full Text Available Time-course expression profiles and methods for spectrum analysis have been applied for detecting transcriptional periodicities, which are valuable patterns to unravel genes associated with cell cycle and circadian rhythm regulation. However, most of the proposed methods suffer from restrictions and large false positives to a certain extent. Additionally, in some experiments, arbitrarily irregular sampling times as well as the presence of high noise and small sample sizes make accurate detection a challenging task. A novel scheme for detecting periodicities in time-course expression data is proposed, in which a real-valued iterative adaptive approach (RIAA, originally proposed for signal processing, is applied for periodogram estimation. The inferred spectrum is then analyzed using Fisher’s hypothesis test. With a proper -value threshold, periodic genes can be detected. A periodic signal, two nonperiodic signals, and four sampling strategies were considered in the simulations, including both bursts and drops. In addition, two yeast real datasets were applied for validation. The simulations and real data analysis reveal that RIAA can perform competitively with the existing algorithms. The advantage of RIAA is manifested when the expression data are highly irregularly sampled, and when the number of cycles covered by the sampling time points is very reduced.

  20. Care of pediatric tracheostomy in the immediate postoperative period and timing of first tube change. (United States)

    Lippert, Dylan; Hoffman, Matthew R; Dang, Phat; McMurray, J Scott; Heatley, Diane; Kille, Tony


    To analyze the safety of a standardized pediatric tracheostomy care protocol in the immediate postoperative period and its impact on tracheostomy related complications. Retrospective case series. Pediatric patients undergoing tracheotomy from February 2010-February 2014. In 2012, a standardized protocol was established regarding postoperative pediatric tracheostomy care. This protocol included securing newly placed tracheostomy tubes using a foam strap with hook and loop fastener rather than twill ties, placing a fresh drain sponge around the tracheostomy tube daily, and performing the first tracheostomy tube change on postoperative day 3 or 4. Outcome measures included rate of skin breakdown and presence of a mature stoma allowing for a safe first tracheostomy tube change. Two types of tracheotomy were performed based on patient age: standard pediatric tracheotomy and adult-style tracheotomy with a Bjork flap. Patients were analyzed separately based on age and the type of tracheotomy performed. Thirty-seven patients in the pre-protocol group and 35 in the post-protocol group were analyzed. The rate of skin breakdown was significantly lower in the post-protocol group (standard: p=0.0048; Bjork flap: p=0.0003). In the post-protocol group, all tube changes were safely accomplished on postoperative day three or four, and the stomas were deemed to be adequately matured to do so in all cases. A standardized postoperative pediatric tracheostomy care protocol resulted in decreased rates of skin breakdown and demonstrated that pediatric tracheostomy tubes can be safely changed as early as 3 days postoperatively. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  1. One-dimensional, time dependent simulation of the planetary boundary layer over a 48-hour period

    International Nuclear Information System (INIS)

    Haschke, D.; Gassmann, F.; Rudin, F.


    Results of a one-dimensional, time dependent simulation of the planetary boundary layer are given. First, a description of the mathematical model used is given and its approximations are discussed. Then a description of the initial and boundary conditions used for the simulation is given. Results are discussed with respect to their agreement with observed data and their precision. It can be demonstrated that a simulation of the planetary boundary layer is possible with satisfactory precision. The incompleteness of observed data gives, however, problems with their use and thus introduces uncertainties into the simulation. As a consequence, the report tries to point to the inherent limitations of such a simulation. (Auth.)

  2. Periodization of the european union’s immigration policy: from the beginning to modern times

    Directory of Open Access Journals (Sweden)

    K. Y. Fogel


    The main conclusion of the article is that, on the one hand, immigration has become a relevant issue in all the EU countries. On the other hand, as a consequence of different timing of immigration, different socio-economic contexts and varying governmental migration and integration policies, different forms of migration, with different governmental policies of migration and integration, and with different types of migrants have evolved. Such different starting positions should be taken into account when studying the consequences of the immigration and the presence of migrants in society.

  3. Simultaneously precise frequency transfer and time synchronization using feed-forward compensation technique via 120 km fiber link. (United States)

    Chen, Xing; Lu, Jinlong; Cui, Yifan; Zhang, Jian; Lu, Xing; Tian, Xusheng; Ci, Cheng; Liu, Bo; Wu, Hong; Tang, Tingsong; Shi, Kebin; Zhang, Zhigang


    Precision time synchronization between two remote sites is desired in many applications such as global positioning satellite systems, long-baseline interferometry, coherent radar detection and fundamental physics constant measurements. The recently developed frequency dissemination technologies based on optical fiber link have improved the transfer instability to the level of 10(-19)/day at remote location. Therefore it is possible to keep clock oscillation at remote locations continuously corrected, or to reproduce a "virtual" clock on the remote location. However the initial alignment and the correction of 1 pps timing signal from time to time are still required, besides the highly stabilized clock frequency transfer between distant locations. Here we demonstrate a time synchronization based on an ultra-stable frequency transfer system via 120-km commercial fiber link by transferring an optical frequency comb. Both the phase noise compensation in frequency dissemination and temporal basis alignment in time synchronization were implemented by a feed-forward digital compensation (FFDC) technique. The fractional frequency instability was measured to be 6.18 × 10(-20) at 2000 s. The timing deviation of time synchronization was measured to be 0.6 ps in 1500 s. This technique also can be applied in multi-node fiber network topology.

  4. Simulation and Analysis of Autonomous Time Synchronization Based on Asynchronism Two-way Inter-satellite Link (United States)

    Fang, L.; Yang, X. H.; Sun, B. Q.; Qin, W. J.; Kong, Y.


    The measurement of the inter-satellite link is one of the key techniques in the autonomous operation of satellite navigation system. Based on the asynchronism inter-satellite two-way measurement mode in GPS constellation, the reduction formula of the inter-satellite time synchronization is built in this paper. Moreover, the corrective method of main systematic errors is proposed. Inter-satellite two-way time synchronization is simulated on the basis of IGS (International GNSS Service) precise ephemeris. The impacts of the epoch domestication of asynchronism inter-satellite link pseudo-range, the initial orbit, and the main systematic errors on satellite time synchronization are analyzed. Furthermore, the broadcast clock error of each satellite is calculated by the ``centralized'' inter-satellite autonomous time synchronization. Simulation results show that the epoch domestication of asynchronism inter-satellite link pseudo-range and the initial orbit have little impact on the satellite clock errors, and thus they needn't be taken into account. The errors caused by the relativistic effect and the asymmetry of path travel have large impact on the satellite clock errors. These should be corrected with theoretical formula. Compared with the IGS precise clock error, the root mean square of the broadcast clock error of each satellite is about 0.4 ns.

  5. Frequency decoding of periodically timed action potentials through distinct activity patterns in a random neural network

    International Nuclear Information System (INIS)

    Reichenbach, Tobias; Hudspeth, A J


    Frequency discrimination is a fundamental task of the auditory system. The mammalian inner ear, or cochlea, provides a place code in which different frequencies are detected at different spatial locations. However, a temporal code based on spike timing is also available: action potentials evoked in an auditory-nerve fiber by a low-frequency tone occur at a preferred phase of the stimulus—they exhibit phase locking—and thus provide temporal information about the tone's frequency. Humans employ this temporal information for discrimination of low frequencies. How might such temporal information be read out in the brain? Here we employ statistical and numerical methods to demonstrate that recurrent random neural networks in which connections between neurons introduce characteristic time delays, and in which neurons require temporally coinciding inputs for spike initiation, can perform sharp frequency discrimination when stimulated with phase-locked inputs. Although the frequency resolution achieved by such networks is limited by the noise in phase locking, the resolution for realistic values reaches the tiny frequency difference of 0.2% that has been measured in humans. (paper)

  6. Arterial link travel time estimation using loop detector data : phase 1 (United States)


    The envisioned operational tests of Advanced Traveler Information Systems (ATIS) and Advanced Traffic Management Systems (ATMS) in the Minneapolis/St. Paul area call for the provision of timely and reliable travel times over an entire rod network. Un...

  7. Tracking of Physical Activity with Accelerometers Over a Two-year Time Period

    DEFF Research Database (Denmark)

    Dencker, Magnus; Tanha, Tina; Wollmer, Per


    BACKGROUND: Limited data exists of tracking and changes in accelerometer measured physical activity in children. METHODS: Physical activity was assessed by accelerometers for four days in 167 children (boys n=90, girls n=77), aged 9.8±0.6 years. Follow-up measurement was made 2.0±0.1 yrs later...... (range 1.9-2.1 yrs). General physical activity (GPA) was defined as mean count/minute. Minutes of inactivity, light- moderate- and vigorous physical activity (LMVPA), moderate and vigorous physical activity (MVPA) and vigorous physical activity (VPA) per day were calculated both as absolute values...... and as percentage of total registration time. RESULTS: Spearman rank order correlation indicated low tracking of MVPA and VPA in girls (r=0.25-0.33, P...

  8. Examining job tenure and lost-time claim rates in Ontario, Canada, over a 10-year period, 1999-2008. (United States)

    Morassaei, Sara; Breslin, F Curtis; Shen, Min; Smith, Peter M


    We sought to examine the association between job tenure and lost-time claim rates over a 10-year period in Ontario, Canada. Data were obtained from workers' compensation records and labour force survey data from 1999 to 2008. Claim rates were calculated for gender, age, industry, occupation, year and job tenure group. A multivariate analysis and examination of effect modification were performed. Differences in injury event and source of injury were also examined by job tenure. Lost-time claim rates were significantly higher for workers with shorter job tenure, regardless of other factors. Claim rates for new workers differed by gender, age and industry, but remained relatively constant at an elevated rate over the observed time period. This study is the first to examine lost-time claim rates by job tenure over a time period during which overall claim rates generally declined. Claim rates did not show a convergence by job tenure. Findings highlight that new workers are still at elevated risk, and suggest the need for improved training, reducing exposures among new workers, promoting permanent employment, and monitoring work injury trends and risk factors.

  9. Novel criteria for global exponential periodicity and stability of recurrent neural networks with time-varying delays

    International Nuclear Information System (INIS)

    Song Qiankun


    In this paper, the global exponential periodicity and stability of recurrent neural networks with time-varying delays are investigated by applying the idea of vector Lyapunov function, M-matrix theory and inequality technique. We assume neither the global Lipschitz conditions on these activation functions nor the differentiability on these time-varying delays, which were needed in other papers. Several novel criteria are found to ascertain the existence, uniqueness and global exponential stability of periodic solution for recurrent neural network with time-varying delays. Moreover, the exponential convergence rate index is estimated, which depends on the system parameters. Some previous results are improved and generalized, and an example is given to show the effectiveness of our method

  10. Estimation of Bimodal Urban Link Travel Time Distribution and Its Applications in Traffic Analysis

    Directory of Open Access Journals (Sweden)

    Yuxiong Ji


    Full Text Available Vehicles travelling on urban streets are heavily influenced by traffic signal controls, pedestrian crossings, and conflicting traffic from cross streets, which would result in bimodal travel time distributions, with one mode corresponding to travels without delays and the other travels with delays. A hierarchical Bayesian bimodal travel time model is proposed to capture the interrupted nature of urban traffic flows. The travel time distributions obtained from the proposed model are then considered to analyze traffic operations and estimate travel time distribution in real time. The advantage of the proposed bimodal model is demonstrated using empirical data, and the results are encouraging.

  11. Parental Control of the Time Preadolescents Spend on Social Media: Links with Preadolescents' Social Media Appearance Comparisons and Mental Health. (United States)

    Fardouly, Jasmine; Magson, Natasha R; Johnco, Carly J; Oar, Ella L; Rapee, Ronald M


    Time spent on social media and making online comparisons with others may influence users' mental health. This study examined links between parental control over the time their child spends on social media, preadolescents' time spent browsing social media, preadolescents' appearance comparisons on social media, and preadolescents' appearance satisfaction, depressive symptoms, and life satisfaction. Preadolescent social media users (N = 284, 49.1% female; aged 10-12) and one of their parents completed online surveys. Preadolescents, whose parents reported greater control over their child's time on social media, reported better mental health. This relationship was mediated by preadolescents spending less time browsing and making fewer appearance comparisons on social media. Parental control over time spent on social media may be associated with benefits for mental health among preadolescents.

  12. Models and synchronization of time-delayed complex dynamical networks with multi-links based on adaptive control

    International Nuclear Information System (INIS)

    Peng Haipeng; Wei Nan; Li Lixiang; Xie Weisheng; Yang Yixian


    In this Letter, time-delay has been introduced in to split the networks, upon which a model of complex dynamical networks with multi-links has been constructed. Moreover, based on Lyapunov stability theory and some hypotheses, we achieve synchronization between two complex networks with different structures by designing effective controllers. The validity of the results was proved through numerical simulations of this Letter.

  13. Experimental Results for Minimum-Time Trajectory Tracking of a Direct-Drive Three-Link Planar Arm

    Energy Technology Data Exchange (ETDEWEB)



    This work is an experimental investigation of the ability of a real three-link direct-drive arm to track model-based minimum-time trajectories that have been found off-line. Sufficiently large velocity gains in the computed torque control law were not achievable with the velocity sensors described herein. This indicates the critical importance of the velocity sensing when attempting to track trajectories that push the envelope of the system's torque capabilities.

  14. Maintaining high precision of isotope ratio analysis over extended periods of time. (United States)

    Brand, Willi A


    Stable isotope ratios are reliable and long lasting process tracers. In order to compare data from different locations or different sampling times at a high level of precision, a measurement strategy must include reliable traceability to an international stable isotope scale via a reference material (RM). Since these international RMs are available in low quantities only, we have developed our own analysis schemes involving laboratory working RM. In addition, quality assurance RMs are used to control the long-term performance of the delta-value assignments. The analysis schemes allow the construction of quality assurance performance charts over years of operation. In this contribution, the performance of three typical techniques established in IsoLab at the MPI-BGC in Jena is discussed. The techniques are (1) isotope ratio mass spectrometry with an elemental analyser for delta(15)N and delta(13)C analysis of bulk (organic) material, (2) high precision delta(13)C and delta(18)O analysis of CO(2) in clean-air samples, and (3) stable isotope analysis of water samples using a high-temperature reaction with carbon. In addition, reference strategies on a laser ablation system for high spatial resolution delta(13)C analysis in tree rings is exemplified briefly.

  15. Time dependent unavailability analysis of nuclear safety systems considering periodically tested components

    International Nuclear Information System (INIS)

    Goes, Alexandre Gromann de Araujo


    It is of utmost importance to have a computer code in order to analyze how different parameters (like test duration time) affect the unavailability of safety systems of nuclear. In this context, a study was performed in order to evaluate the model employed by the FRANTIC computer code, which performs detailed calculations on the contribution to the system unavailability originated by hardware failures, component tests and repairs, aiming at considering the influence of different test schemes on the system unavailability. It was shown, by means of the results attained that the numerical model used by the FRANTIC code and the analytical model proposed by APOSTOLAKIS and CHU (4) give unavailability values much similar when the component tests are supposed to be perfect. When a test is supposed to be imperfect (that is, when it may induce a test is supposed to be imperfect (that is, when it may induce a failure on the component being tested), the analytical model presents more conservative results. (author)

  16. Time resolved FTIR study of the catalytic CO oxidation under periodic variation of the reactant concentration

    Energy Technology Data Exchange (ETDEWEB)

    Kritzenberger, J; Wokaun, A [Paul Scherrer Inst. (PSI), Villigen (Switzerland)


    Oxidation of CO over palladium/zirconia catalyst obtained from an amorphous Pd{sub 25}Zr{sub 75} precursor was investigated by time resolved FTIR spectroscopy. Sine wave shaped modulation of the reactant concentration, i.e. variation of CO or O{sub 2} partial pressure, was used to induce variations of the IR signals of product (CO{sub 2}) and unconverted reactant (CO), which were detected in a multi-pass absorption cell. The phase shift {phi} between external perturbation and variation of the CO{sub 2} signal was examined in dependence on temperature (100{sup o}C{<=}T{<=}350{sup o}C) and modulation frequency (1.39x10{sup -4}Hz{<=}{omega}{<=}6.67x10{sup -2}Hz). From the phase shift values, a simple Eley-Rideal mechanism is excluded, and the rate limiting step of the Langmuir-Hinshelwood mechanism for the CO oxidation may be identified. Adsorption and possible surface movement of CO to the actual reaction site determine the rate of the CO oxidation on the palladium/zirconia catalyst used in our study. The introduction of an external perturbation is a first step towards the application of two-dimensional infrared spectroscopy to heterogeneous catalyzed reactions. (author) 3 figs., 4 refs.

  17. Exploring What Determines the Use of Forecasts of Varying Time Periods in Guanacaste, Costa Rica (United States)

    Babcock, M.; Wong-Parodi, G.; Grossmann, I.; Small, M. J.


    Weather and climate forecasts are promoted as ways to improve water management, especially in the face of changing environmental conditions. However, studies indicate many stakeholders who may benefit from such information do not use it. This study sought to better understand which personal factors (e.g., trust in forecast sources, perceptions of accuracy) were important determinants of the use of 4-day, 3-month, and 12-month rainfall forecasts by stakeholders in water management-related sectors in the seasonally dry province of Guanacaste, Costa Rica. From August to October 2015, we surveyed 87 stakeholders from a mix of government agencies, local water committees, large farms, tourist businesses, environmental NGO's, and the public. The result of an exploratory factor analysis suggests that trust in "informal" forecast sources (traditional methods, family advice) and in "formal" sources (government, university and private company science) are independent of each other. The result of logistic regression analyses suggest that 1) greater understanding of forecasts is associated with a greater probability of 4-day and 3-month forecast use, but not 12-month forecast use, 2) a greater probability of 3-month forecast use is associated with a lower level of trust in "informal" sources, and 3), feeling less secure about water resources, and regularly using many sources of information (and specifically formal meetings and reports) are each associated with a greater probability of using 12-month forecasts. While limited by the sample size, and affected by the factoring method and regression model assumptions, these results do appear to suggest that while forecasts of all times scales are used to some extent, local decision makers' decisions to use 4-day and 3-month forecasts appear to be more intrinsically motivated (based on their level of understanding and trust) and the use of 12-month forecasts seems to be more motivated by a sense of requirement or mandate.

  18. Five Fallacies Used to Link Black Holes to Einstein's Relativistic Space-Time

    Directory of Open Access Journals (Sweden)

    Weller D. L.


    Full Text Available For a particle falling radially toward a compact mass, the Schwarzschild metric maps local time to coordinate time based on radial locations reached by the particle. The mapping shows the particle will not cross a critical radius regardless of the coordinate used to measure time. Herein are discussed five fallacies that have been used to make it appear the particle can cross the critical radius.

  19. Five Fallacies Used to Link Black Holes to Einstein’s Relativistic Space-Time

    Directory of Open Access Journals (Sweden)

    Weller D. L.


    Full Text Available For a particle falling radially toward a compact mass, the Schwarzschild metric maps local time to coordinate time based on radial locations reached by the particle. The mapping shows the particle will not cross a critical radius regardless of the coordinate used to measure time. Herein are discussed five fallacies that have been used to make it appear the particle can cross the critical radius.

  20. Testing Time and Frequency Fiber-Optic Link Transfer by Hardware Emulation of Acoustic-Band Optical Noise

    Directory of Open Access Journals (Sweden)

    Lipiński Marcin


    Full Text Available The low-frequency optical-signal phase noise induced by mechanical vibration of the base occurs in field-deployed fibers. Typical telecommunication data transfer is insensitive to this type of noise but the phenomenon may influence links dedicated to precise Time and Frequency (T&F fiber-optic transfer that exploit the idea of stabilization of phase or propagation delay of the link. To measure effectiveness of suppression of acoustic noise in such a link, a dedicated measurement setup is necessary. The setup should enable to introduce a low-frequency phase corruption to the optical signal in a controllable way. In the paper, a concept of a setup in which the mechanically induced acoustic-band optical signal phase corruption is described and its own features and measured parameters are presented. Next, the experimental measurement results of the T&F transfer TFTS-2 system’s immunity as a function of the fibre-optic length vs. the acoustic-band noise are presented. Then, the dependency of the system immunity on the location of a noise source along the link is also pointed out.

  1. A Simple Time Domain Collocation Method to Precisely Search for the Periodic Orbits of Satellite Relative Motion

    Directory of Open Access Journals (Sweden)

    Xiaokui Yue


    Full Text Available A numerical approach for obtaining periodic orbits of satellite relative motion is proposed, based on using the time domain collocation (TDC method to search for the periodic solutions of an exact J2 nonlinear relative model. The initial conditions for periodic relative orbits of the Clohessy-Wiltshire (C-W equations or Tschauner-Hempel (T-H equations can be refined with this approach to generate nearly bounded orbits. With these orbits, a method based on the least-squares principle is then proposed to generate projected closed orbit (PCO, which is a reference for the relative motion control. Numerical simulations reveal that the presented TDC searching scheme is effective and simple, and the projected closed orbit is very fuel saving.

  2. High-order fuzzy time-series based on multi-period adaptation model for forecasting stock markets (United States)

    Chen, Tai-Liang; Cheng, Ching-Hsue; Teoh, Hia-Jong


    Stock investors usually make their short-term investment decisions according to recent stock information such as the late market news, technical analysis reports, and price fluctuations. To reflect these short-term factors which impact stock price, this paper proposes a comprehensive fuzzy time-series, which factors linear relationships between recent periods of stock prices and fuzzy logical relationships (nonlinear relationships) mined from time-series into forecasting processes. In empirical analysis, the TAIEX (Taiwan Stock Exchange Capitalization Weighted Stock Index) and HSI (Heng Seng Index) are employed as experimental datasets, and four recent fuzzy time-series models, Chen’s (1996), Yu’s (2005), Cheng’s (2006) and Chen’s (2007), are used as comparison models. Besides, to compare with conventional statistic method, the method of least squares is utilized to estimate the auto-regressive models of the testing periods within the databases. From analysis results, the performance comparisons indicate that the multi-period adaptation model, proposed in this paper, can effectively improve the forecasting performance of conventional fuzzy time-series models which only factor fuzzy logical relationships in forecasting processes. From the empirical study, the traditional statistic method and the proposed model both reveal that stock price patterns in the Taiwan stock and Hong Kong stock markets are short-term.

  3. Near-optimality of special periodic protocols for fluid models of single server switched networks with switchover times (United States)

    Matveev, A. S.; Ishchenko, R.


    We consider a generic deterministic time-invariant fluid model of a single server switched network, which consists of finitely many infinite size buffers (queues) and receives constant rate inflows of jobs from the outside. Any flow undergoes a multi-phase service, entering a specific buffer after every phase, and ultimately leaves the network; the route of the flow over the buffers is pre-specified, and flows may merge inside the network. They share a common source of service, which can serve at most one buffer at a time and has to switch among buffers from time to time; any switch consumes a nonzero switchover period. With respect to the long-run maximal scaled wip (work in progress) performance metric, near-optimality of periodic scheduling and service protocols is established: the deepest optimum (that is over all feasible processes in the network, irrespective of the initial state) is furnished by such a protocol up to as small error as desired. Moreover, this can be achieved with a special periodic protocol introduced in the paper. It is also shown that the exhaustive policy is optimal for any buffer whose service at the maximal rate does not cause growth of the scaled wip.

  4. Time perspective and socioeconomic status: a link to socioeconomic disparities in health? (United States)

    Guthrie, Lori C; Butler, Stephen C; Ward, Michael M


    Time perspective is a measure of the degree to which one's thinking is motivated by considerations of the future, present, or past. Time perspective has been proposed as a potential mediator of socioeconomic disparities in health because it has been associated with health behaviors and is presumed to vary with socioeconomic status. In this cross-sectional community-based survey of respondents recruited from hair salons and barber shops in a suburb of Washington DC, we examined the association between time perspective and both education level and occupation. We asked participants (N=525) to complete a questionnaire that included three subscales (future, present-fatalistic, and present-hedonistic) of the Zimbardo Time Perspective Inventory. Participants with more formal education and those with professional occupations had higher scores on the future time perspective subscale, and lower scores on the present-fatalistic subscale, than participants with less formal education or a non-professional occupation. Present-fatalistic scores were also higher among participants whose parents had less formal education. Present-hedonistic scores were not associated with either education level or professional occupation. Time perspective scores were not independently associated with the likelihood of obesity, smoking, or exercise. In this community sample, future time perspective was associated with current socioeconomic status, and past-fatalistic time perspective was associated with both current and childhood socioeconomic status.

  5. Rapid supersensitive laser-semiconductor monitoring system. Time period covered: Dec. 15, 1993 - Dec. 15, 1994

    International Nuclear Information System (INIS)

    Pugatch, V.M.


    The creation of the rapid and sensitive system for the determination of the Alpha-radioactivity in the Environmental samples has been determined as the main goal of the Research Contract No. 7200RO/RB. As a result of the first stage of the research accomplished in the year 1993, the prototype of the system based on the combination of the laser photoionization mass spectrometry and many-channel alpha-spectrometer has been built and tested. To improve the sensitivity it was proposed to add one more stage to the laser photoionization mass-spectrometer. To develop the high position sensitivity of the system it was proposed to include into the alpha-radiometer SI strip-detector with submicron position sensitivity. Hardware and software for the laser-semiconductor monitoring system of alpha-radionuclides in the environment have been further developed and tested in frames of the IAEA Research Contract No. 7200/R1/RB. Optimization of the sample evaporation with one more stage of photoionization has been successfully performed in the laser photoionization mass-spectrometer. The automatization of the measurement procedure is under way by means of the IBM PC-386 and specially designed electronic units. The evaluated sensitivity of the new set-up is in the range of 1.0 Bq/kg. A bulk measurement of the alpha-radioactivity concentration in soil samples from the Chernobyl region (100 km) have been performed by means of thick samples method and built under this contract alpha-radiometer with large area SI semiconductor detectors. The lowest detectable level was in the range 100 Bq/kg without any radiochemical separation. Comparison with the data obtained for the same probes by means of the thin sample (with radiochemical separation) has shown higher Pu-concentration values obtained by means of the thick samples. For the first time the Sl-strip-detector with 128 channels has been applied for the alpha-radiometry purposes. Different read-out electronics (including the most

  6. Social contact patterns of school-age children in Taiwan: comparison of the term time and holiday periods. (United States)

    Chen, S-C; You, Z-S


    School closure is one of the most common interventions in the early weeks of an influenza pandemic. Few studies have investigated social contact patterns and compared individual student contact characteristics during the school term and holiday periods in Taiwan. Here, we conducted a well-used questionnaire survey in a junior high school (grades 7-8) in June 2013. All 150 diary-based effective questionnaires covering conversation and skin-to-skin contact behaviour were surveyed. Two questionnaires for each participant were designed to investigate the individual-level difference of contact numbers per day during the two periods. The questionnaire response rate was 44%. The average number of contacts during term time (20·0 contacts per day) and holiday periods (12·6 contacts per day) were significantly different (P holiday periods, the number of contacts decreased by 40%. This study is the first research to investigate the contact numbers and contact characteristics for school-age children during the school term and a holiday period in Taiwan. With regard to public health, this study could provide the basic contact information and database for modelling influenza epidemics for minimizing the spread of influenza that depends on personal contacts for transmission.

  7. Effects of age, time period, and birth cohort on the prevalence of diabetes and obesity in Korean men. (United States)

    Kwon, Jin-Won; Song, Yun-mi; Park, Hye soon; Sung, Joohon; Kim, Ho; Cho, Sung-il


    We examined changes in the prevalence of diabetes, obesity, and overweight in 412,881 Korean men in birth cohorts from 1933 to 1972 over 8 years from 1992 to 2000 and separately analyzed the effects of age, time period, and birth cohort. The study included male employees of Korean government organizations and schools who were between 20 and 59 years of age in 1992. Diabetes was diagnosed on the basis of self-reports in 1992 or fasting blood glucose levels (>or=126 mg/ml, 7.0 mmol/l). The age-period-cohort model was used to estimate the effects of age, time period, and birth cohort. In Korean male birth cohorts from 1933 to 1972, the age-specific prevalence of diabetes, obesity, and overweight in men aged 28-59 years increased annually by 0.41% (3.03 to 6.29%), 0.18% (0.70 to 2.16%), and 1.49% (23.48 to 35.41%), respectively, from 1992 to 2000. The relative change in diabetes was largest among the younger cohorts (>400% increase over 8 years) and corresponded to the change in obesity. Apart from the contribution of age, clear cohort and period effects were evident for diabetes, although the magnitude of the effect was slightly less than that for obesity. Prevention of diabetes through the control of obesity, particularly in young men, clearly needs to be emphasized.

  8. Time spent in housework and leisure: links with parents' physiological recovery from work. (United States)

    Saxbe, Darby E; Repetti, Rena L; Graesch, Anthony P


    Spouses' balancing of housework and leisure activities at home may affect their recovery from work. This paper reports on a study of everyday family life in which 30 dual-earner couples were tracked around their homes by researchers who recorded their locations and activities every 10 min. For women, the most frequently pursued activities at home were housework, communication, and leisure; husbands spent the most time in leisure activities, followed by communication and housework. Spouses differed in their total time at home and their proportion of time devoted to leisure and housework activities, with wives observed more often in housework and husbands observed more often in leisure activities. Both wives and husbands who devoted more time to housework had higher levels of evening cortisol and weaker afternoon-to-evening recovery. For wives, husbands' increased housework time also predicted stronger evening cortisol recovery. When both spouses' activities were entered in the same model, leisure predicted husbands' evening cortisol, such that husbands who apportioned more time to leisure, and whose wives apportioned less time to leisure, showed stronger after-work recovery. These results suggest that the division of labor within couples may have implications for physical health.

  9. Output-only modal analysis of linear time-periodic systems with application to wind turbine simulation data

    DEFF Research Database (Denmark)

    Allen, Matthew S.; Sracic, Michael W.; Chauhan, Shashank


    to interrogate simulated measurements from a rotating wind turbine. The measurements were simulated for a 5 MW turbine modeled in the HAWC2 simulation code, which includes both structural dynamic and aerodynamic effects. This simulated system identification provides insights into the test and measurement......Many important systems, such as wind turbines, helicopters and turbomachinery, must be modeled with linear time-periodic equations of motion to correctly predict resonance phenomena. Time periodic effects in wind turbines might arise due to blade-to-blade manufacturing variations, stratification...... in the velocity of the wind with height and changes in the aerodynamics of the blades as they pass the tower. These effects may cause parametric resonance or other unexpected phenomena, so it is important to properly characterize them so that these machines can be designed to achieve high reliability, safety...

  10. The strain effect on the Dirac electrons tunneling through the time-periodic scalar and vector barriers

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Weixian, E-mail:


    The tunneling of the massless and massive Dirac particle through the strained barriers driven by the time-periodic scalar potentials and the static vector potentials is investigated, where the interrelationships among the strain, the incidence angle, the dynamic scalar potential, the magnetic field and the transmission of the Dirac particle have been discussed. In either massless or massive case, the intersection angle between the obliquely incident Dirac particle and strain determines the extent of deviation of the tunneling profiles from the strainless case. The time-periodic scalar potentials can enhance the capability of the Dirac particle to surmount the energy gap induced by the mass, reflecting quantum nature of the photon-assisted tunneling. When the magnetic field is switched on, the transmission overall presents a remarkably different profile, and decreases with the increase of the magnetic fields due to the conservation of the transverse momentum, which reduces the number of the side-band channels for tunneling.

  11. A new criterion to global exponential periodicity for discrete-time BAM neural network with infinite delays

    International Nuclear Information System (INIS)

    Zhou Tiejun; Liu Yuehua; Li Xiaoping; Liu Yirong


    The discrete-time bidirectional associative memory neural network with periodic coefficients and infinite delays is studied. And not by employing the continuation theorem of coincidence degree theory as other literatures, but by constructing suitable Liapunov function, using fixed point theorem and some analysis techniques, a sufficient criterion is obtained which ensures the existence and global exponential stability of periodic solution for the type of discrete-time BAM neural network. The obtained result is less restrictive to the BAM neural networks than previously known criteria. Furthermore, it can be applied to the BAM neural network which signal transfer functions are neither bounded nor differentiable. In addition, an example and its numerical simulation are given to illustrate the effectiveness of the obtained result

  12. Stability of small-amplitude periodic solutions near Hopf bifurcations in time-delayed fully-connected PLL networks (United States)

    Ferruzzo Correa, Diego P.; Bueno, Átila M.; Castilho Piqueira, José R.


    In this paper we investigate stability conditions for small-amplitude periodic solutions emerging near symmetry-preserving Hopf bifurcations in a time-delayed fully-connected N-node PLL network. The study of this type of systems which includes the time delay between connections has attracted much attention among researchers mainly because the delayed coupling between nodes emerges almost naturally in mathematical modeling in many areas of science such as neurobiology, population dynamics, physiology and engineering. In a previous work it has been shown that symmetry breaking and symmetry preserving Hopf bifurcations can emerge in the parameter space. We analyze the stability along branches of periodic solutions near fully-synchronized Hopf bifurcations in the fixed-point space, based on the reduction of the infinite-dimensional space onto a two-dimensional center manifold in normal form. Numerical results are also presented in order to confirm our analytical results.

  13. Time trends of esophageal and gastric cancer mortality in China, 1991?2009: an age-period-cohort analysis


    Li, Mengmeng; Wan, Xia; Wang, Yanhong; Sun, Yuanyuan; Yang, Gonghuan; Wang, Li


    Esophageal and gastric cancers share some risk factors. This study aimed to compare the long-term trends in mortality rates of esophageal and gastric cancers in China to provide evidence for cancer prevention and control. Mortality data were derived from 103 continuous points of the Disease Surveillance Points system during 1991?2009, stratified by gender and urban-rural locations. Age-period-cohort models were used to disentangle the time trends of esophageal and gastric cancer mortality. Th...

  14. Linking melodic expectation to expressive performance timing and perceived musical tension. (United States)

    Gingras, Bruno; Pearce, Marcus T; Goodchild, Meghan; Dean, Roger T; Wiggins, Geraint; McAdams, Stephen


    This research explored the relations between the predictability of musical structure, expressive timing in performance, and listeners' perceived musical tension. Studies analyzing the influence of expressive timing on listeners' affective responses have been constrained by the fact that, in most pieces, the notated durations limit performers' interpretive freedom. To circumvent this issue, we focused on the unmeasured prelude, a semi-improvisatory genre without notated durations. In Experiment 1, 12 professional harpsichordists recorded an unmeasured prelude on a harpsichord equipped with a MIDI console. Melodic expectation was assessed using a probabilistic model (IDyOM [Information Dynamics of Music]) whose expectations have been previously shown to match closely those of human listeners. Performance timing information was extracted from the MIDI data using a score-performance matching algorithm. Time-series analyses showed that, in a piece with unspecified note durations, the predictability of melodic structure measurably influenced tempo fluctuations in performance. In Experiment 2, another 10 harpsichordists, 20 nonharpsichordist musicians, and 20 nonmusicians listened to the recordings from Experiment 1 and rated the perceived tension continuously. Granger causality analyses were conducted to investigate predictive relations among melodic expectation, expressive timing, and perceived tension. Although melodic expectation, as modeled by IDyOM, modestly predicted perceived tension for all participant groups, neither of its components, information content or entropy, was Granger causal. In contrast, expressive timing was a strong predictor and was Granger causal. However, because melodic expectation was also predictive of expressive timing, our results outline a complete chain of influence from predictability of melodic structure via expressive performance timing to perceived musical tension. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  15. A statistical method linking geological and historical eruption time series for volcanic hazard estimations: Applications to active polygenetic volcanoes (United States)

    Mendoza-Rosas, Ana Teresa; De la Cruz-Reyna, Servando


    The probabilistic analysis of volcanic eruption time series is an essential step for the assessment of volcanic hazard and risk. Such series describe complex processes involving different types of eruptions over different time scales. A statistical method linking geological and historical eruption time series is proposed for calculating the probabilities of future eruptions. The first step of the analysis is to characterize the eruptions by their magnitudes. As is the case in most natural phenomena, lower magnitude events are more frequent, and the behavior of the eruption series may be biased by such events. On the other hand, eruptive series are commonly studied using conventional statistics and treated as homogeneous Poisson processes. However, time-dependent series, or sequences including rare or extreme events, represented by very few data of large eruptions require special methods of analysis, such as the extreme-value theory applied to non-homogeneous Poisson processes. Here we propose a general methodology for analyzing such processes attempting to obtain better estimates of the volcanic hazard. This is done in three steps: Firstly, the historical eruptive series is complemented with the available geological eruption data. The linking of these series is done assuming an inverse relationship between the eruption magnitudes and the occurrence rate of each magnitude class. Secondly, we perform a Weibull analysis of the distribution of repose time between successive eruptions. Thirdly, the linked eruption series are analyzed as a non-homogeneous Poisson process with a generalized Pareto distribution as intensity function. As an application, the method is tested on the eruption series of five active polygenetic Mexican volcanoes: Colima, Citlaltépetl, Nevado de Toluca, Popocatépetl and El Chichón, to obtain hazard estimates.

  16. Time trends in upper gastrointestinal diseases and Helicobacter pylori infection in a multiracial Asian population--a 20-year experience over three time periods. (United States)

    Leow, A H-R; Lim, Y-Y; Liew, W-C; Goh, K-L


    Marked epidemiological changes in upper gastrointestinal diseases and Helicobacter pylori infection have taken place in the Asian Pacific region. In particular, differences with respect to race in the multiracial Asian population in Malaysia have been important and interesting. A time trend study of upper gastrointestinal disease and H. pylori infection in three time periods: 1989-1990, 1999-2000 and 2009-2010 spanning a period of 20 years was carried out. Consecutive first time gastroscopies carried out on patients attending the University of Malaya Medical Center were studied. Diagnoses and H. pylori infection status were carefully recorded. A steady decline in prevalence of duodenal ulcer (DU) and gastric ulcer (GU) from 21.1% to 9.5% to 5.0% and from 11.9% to 9.4% to 9.9% while an increase in erosive oesophagitis (EO) from 2.0% to 8.4% to 9.5% (chi-square for trend; P Chinese and Indians but the difference over time was most marked in Malays. There was a steady decline in the proportion of patients with gastric and oesophageal cancers. Peptic ulcers have declined significantly over a 20-year period together with a decline in H. pylori infection. In contrast, a steady increase in erosive oesophagitis was observed. Gastric and oesophageal squamous cell cancers have declined to low levels. © 2016 John Wiley & Sons Ltd.

  17. Periodic protein adsorption at the gold/biotin aqueous solution interface: evidence of kinetics with time delay (United States)

    Neff, H.; Laborde, H. M.; Lima, A. M. N.


    An oscillatory molecular adsorption pattern of the protein neutravidin from aqueous solution onto gold, in presence of a pre-deposited self assembled mono-molecular biotin film, is reported. Real time surface Plasmon resonance sensing was utilized for evaluation of the adsorption kinetics. Two different fractions were identified: in the initial phase, protein molecules attach irreversibly onto the Biotin ligands beneath towards the jamming limit, forming a neutravidin-biotin fraction. Afterwards, the growth rate exhibits distinct, albeit damped adsorption-desorption oscillations over an extended time span, assigned to a quasi reversibly bound fraction. These findings agree with, and firstly confirm a previously published model, proposing macro-molecular adsorption with time delay. The non-linear dynamic model is applicable to and also resembles non-damped oscillatory binding features of the hetero-catalytic oxidation of carbon monoxide molecules on platinum in the gas phase. An associated surface residence time can be linked to the dynamics and time scale required for self-organization.

  18. Analysis of Quasi-periodic Oscillations and Time Lag in Ultraluminous X-Ray Sources with XMM-Newton

    Energy Technology Data Exchange (ETDEWEB)

    Li, Zi-Jian; Xiao, Guang-Cheng; Zhang, Shu; Ma, Xiang; Yan, Lin-Li; Qu, Jin-Lu [Key Laboratory for Particle Astrophysics, Institute of High Energy Physics, Chinese Academy of Sciences, 19B Yuquan Road, Beijing 100049 (China); Chen, Li; Bu, Qing-Cui; Zhang, Liang, E-mail:, E-mail: [Department of Astronomy, Beijing Normal University, Beijing 100875 (China)


    We investigated the power density spectrum (PDS) and time lag of ultraluminous X-ray sources (ULXs) observed by XMM-Newton . We determined the PDSs for each ULX and found that five of them show intrinsic variability due to obvious quasi-periodic oscillations (QPOs) of mHz–1 Hz, consistent with previous reports. We further investigated these five ULXs to determine their possible time lag. The ULX QPOs exhibit a soft time lag that is linearly related to the QPO frequency. We discuss the likelihood of the ULX QPOs being type-C QPO analogs, and the time lag models. The ULXs might harbor intermediate-mass black holes if their QPOs are type-C QPO analogs. We suggest that the soft lag and the linearity may be due to reverberation.

  19. Real time 1.55 μm VCSEL-based coherent detection link

    DEFF Research Database (Denmark)

    Rodes Lopez, Roberto; Parekh, D.; Jensen, Jesper Bevensee


    This paper presents an experimental demonstration of VCSEL-based PON with simplified real-time coherent receiver at 2.5 Gbps. Receiver sensitivity of −37 dBm is achieved proving splitting ratio up to 2048 after 17 km fiber transmission.......This paper presents an experimental demonstration of VCSEL-based PON with simplified real-time coherent receiver at 2.5 Gbps. Receiver sensitivity of −37 dBm is achieved proving splitting ratio up to 2048 after 17 km fiber transmission....

  20. Possible Link between Medical Students' Motivation for Academic Work and Time Engaged in Physical Exercise (United States)

    Aung, Myo Nyein; Somboonwong, Juraiporn; Jaroonvanichkul, Vorapol; Wannakrairot, Pongsak


    Physical exercise results in an active well-being. It is likely that students' engagement in physical exercise keeps them motivated to perform academic endeavors. This study aimed to assess the relation of time engaged in physical exercise with medical students' motivation for academic work. Prospectively, 296 second-year medical students…

  1. 12 CFR 204.134 - Linked time deposits and transaction accounts. (United States)


    ... RESERVE SYSTEM RESERVE REQUIREMENTS OF DEPOSITORY INSTITUTIONS (REGULATION D) Interpretations § 204.134...) establishes general reserve requirements on transaction accounts and nonpersonal time deposits. Under section... other than to allow the payment of higher interest through the avoidance of reserve requirements. As the...

  2. Linking the fractional derivative and the Lomnitz creep law to non-Newtonian time-varying viscosity (United States)

    Pandey, Vikash; Holm, Sverre


    Many of the most interesting complex media are non-Newtonian and exhibit time-dependent behavior of thixotropy and rheopecty. They may also have temporal responses described by power laws. The material behavior is represented by the relaxation modulus and the creep compliance. On the one hand, it is shown that in the special case of a Maxwell model characterized by a linearly time-varying viscosity, the medium's relaxation modulus is a power law which is similar to that of a fractional derivative element often called a springpot. On the other hand, the creep compliance of the time-varying Maxwell model is identified as Lomnitz's logarithmic creep law, making this possibly its first direct derivation. In this way both fractional derivatives and Lomnitz's creep law are linked to time-varying viscosity. A mechanism which yields fractional viscoelasticity and logarithmic creep behavior has therefore been found. Further, as a result of this linking, the curve-fitting parameters involved in the fractional viscoelastic modeling, and the Lomnitz law gain physical interpretation.

  3. Constrained choices? Linking employees' and spouses' work time to health behaviors. (United States)

    Fan, Wen; Lam, Jack; Moen, Phyllis; Kelly, Erin; King, Rosalind; McHale, Susan


    There are extensive literatures on work conditions and health and on family contexts and health, but less research asking how a spouse or partners' work conditions may affect health behaviors. Drawing on the constrained choices framework, we theorized health behaviors as a product of one's own time and spouses' work time as well as gender expectations. We examined fast food consumption and exercise behaviors using survey data from 429 employees in an Information Technology (IT) division of a U.S. Fortune 500 firm and from their spouses. We found fast food consumption is affected by men's work hours-both male employees' own work hours and the hours worked by husbands of women respondents-in a nonlinear way. The groups most likely to eat fast food are men working 50 h/week and women whose husbands work 45-50 h/week. Second, exercise is better explained if work time is conceptualized at the couple, rather than individual, level. In particular, neo-traditional arrangements (where husbands work longer than their wives) constrain women's ability to engage in exercise but increase odds of men exercising. Women in couples where both partners are working long hours have the highest odds of exercise. In addition, women working long hours with high schedule control are more apt to exercise and men working long hours whose wives have high schedule flexibility are as well. Our findings suggest different health behaviors may have distinct antecedents but gendered work-family expectations shape time allocations in ways that promote men's and constrain women's health behaviors. They also suggest the need to expand the constrained choices framework to recognize that long hours may encourage exercise if both partners are looking to sustain long work hours and that work resources, specifically schedule control, of one partner may expand the choices of the other. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. PET System Synchronization and Timing Resolution Using High-Speed Data Links


    Aliaga Varea, Ramón José; Monzó Ferrer, José María; SPAGGIARI, MICHELE; Ferrando Jódar, Néstor; Gadea Gironés, Rafael; Colom Palero, Ricardo José


    Current PET systems with fully digital trigger rely on early digitization of detector signals and the use of digital processors, usually FPGAs, for recognition of valid gamma events on single detectors. Timestamps are assigned and later used for coincidence analysis. In order to maintain a decent timing resolution for events detected on different acquisition boards, it is necessary that local timestamps on different FPGAs be synchronized. Sub-nanosecond accuracy is mandatory if we want this e...

  5. Fusion Approaches for Land Cover Map Production Using High Resolution Image Time Series without Reference Data of the Corresponding Period

    Directory of Open Access Journals (Sweden)

    Benjamin Tardy


    Full Text Available Optical sensor time series images allow one to produce land cover maps at a large scale. The supervised classification algorithms have been shown to be the best to produce maps automatically with good accuracy. The main drawback of these methods is the need for reference data, the collection of which can introduce important production delays. Therefore, the maps are often available too late for some applications. Domain adaptation methods seem to be efficient for using past data for land cover map production. According to this idea, the main goal of this study is to propose several simple past data fusion schemes to override the current land cover map production delays. A single classifier approach and three voting rules are considered to produce maps without reference data of the corresponding period. These four approaches reach an overall accuracy of around 80% with a 17-class nomenclature using Formosat-2 image time series. A study of the impact of the number of past periods used is also done. It shows that the overall accuracy increases with the number of periods used. The proposed methods require at least two or three previous years to be used.

  6. What time periods of the day are concerning for parents of children with attention deficit hyperactivity disorder?

    Directory of Open Access Journals (Sweden)

    Masahide Usami

    Full Text Available BACKGROUND/AIM: The questionnaire-children with difficulties (QCD is a parent-assessed questionnaire designed to evaluate a child's difficulties in functioning during specific time periods of the day. In this study, the QCD was applied to determine the time periods of the day that are concerning for the parents of children with attention deficit hyperactivity disorder (ADHD. The results were compared with those for a community sample. METHODS: Elementary and junior high school students with ADHD (243 boys, 55 girls and a community sample of children (518 boys, 618 girls were enrolled in this study. Their behaviors were assessed by the QCD, the ADHD-rating scale (ADHD-RS, and the Oppositional Defiant Behavior Inventory (ODBI. The effects of gender (boy/girl and diagnosis (ADHD/community sample on the total QCD score were analyzed across each school grade (elementary/junior high school. Correlation coefficients between QCD and ADHD-RS/ODBI scores were analyzed. RESULTS: The QCD score for the ADHD group was significantly lower than that for the community sample (P 0.41, P 0.40, P < 0.001. CONCLUSIONS: Parents reported that children with ADHD faced greater difficulties in completing basic daily activities compared with the community controls, particularly in the evening. Furthermore, these difficulties were related to the severity of ADHD symptoms. The parents' perceptions depended on the gender, ADHD and oppositional symptoms, and the time period of the day. This study determined that children with ADHD face greater difficulties in daily functioning compared with community sample children, that these difficulties are time-dependent, and that these difficulties were particularly experienced in the evening.

  7. Existence and global exponential stability of periodic solution of memristor-based BAM neural networks with time-varying delays. (United States)

    Li, Hongfei; Jiang, Haijun; Hu, Cheng


    In this paper, we investigate a class of memristor-based BAM neural networks with time-varying delays. Under the framework of Filippov solutions, boundedness and ultimate boundedness of solutions of memristor-based BAM neural networks are guaranteed by Chain rule and inequalities technique. Moreover, a new method involving Yoshizawa-like theorem is favorably employed to acquire the existence of periodic solution. By applying the theory of set-valued maps and functional differential inclusions, an available Lyapunov functional and some new testable algebraic criteria are derived for ensuring the uniqueness and global exponential stability of periodic solution of memristor-based BAM neural networks. The obtained results expand and complement some previous work on memristor-based BAM neural networks. Finally, a numerical example is provided to show the applicability and effectiveness of our theoretical results. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Identification of five time periods on the Indonesian stock exchange index historical data since 1997 to 2016 (United States)

    Riveli, N.; Suroto, B. J.


    We are investigating the behavioural changes of the Indonesian financial systems in the last 20 years. Changes in the financial system behaviour were indicated by differences in the statistical properties of the daily log return distribution in two adjacent time windows. To measure how likely two distributions are differ, the Kolmogorov-Smirnov (KS) Test was applied. We have found that we can divide our time series data into five segments, where the KS probability values between two adjacent segments are maximum. This finding can be used to study the effect on the financial system imposed by, for example, the socio-economy and political policy by the government, by studying the changes in such factors in the identified time periods.

  9. Modelling regional variation of first-time births in Denmark 1980-1994 by an age-period-cohort model

    DEFF Research Database (Denmark)

    Thygesen, Lau Caspar; Knudsen, Lisbeth B.; Keiding, Niels


    Despite the small size of Denmark, there have traditionally been rather consistent regional differences in fertility rates. We apply the statistical age-period-cohort model to include the effect of these three time-related factors thereby concisely illuminating the regional differences of first......-time births in Denmark. From the Fertility of Women and Couples Dataset we obtain data on number of births by nulliparous women by year (1980-1994), age (15-45) and county of residence. We show that the APC-model describes the fertility rates of nulliparous women satisfactorily. To catch the regional...... variation an interaction parameter between age and county is necessary, which provides a surprisingly good description suggesting that the county-specific age-distributions of first-time fertility rates differ. Our results are in general agreement with the 'moral geography' concepts of Tonboe (2001)....

  10. Modelling regional variation of first-time births in Denmark 1980-1994 by an age-period-cohort model

    Directory of Open Access Journals (Sweden)

    Lisbeth B. Knudsen


    Full Text Available Despite the small size of Denmark, there have traditionally been rather consistent regional differences in fertility rates. We apply the statistical age-period-cohort model to include the effect of these three time-related factors thereby concisely illuminating the regional differences of first-time births in Denmark. From the Fertility of Women and Couples Dataset we obtain data on number of births by nulliparous women by year (1980-1994, age (15-45 and county of residence. We show that the APC-model describes the fertility rates of nulliparous women satisfactorily. To catch the regional variation an interaction parameter between age and county is necessary, which provides a surprisingly good description suggesting that the county-specific age-distributions of first-time fertility rates differ. Our results are in general agreement with the 'moral geography' concepts of Tonboe (2001.

  11. Spatial distribution of triazine residues in a shallow alluvial aquifer linked to groundwater residence time. (United States)

    Sassine, Lara; Le Gal La Salle, Corinne; Khaska, Mahmoud; Verdoux, Patrick; Meffre, Patrick; Benfodda, Zohra; Roig, Benoît


    At present, some triazine herbicides occurrence in European groundwater, 13 years after their use ban in the European Union, remains of great concern and raises the question of their persistence in groundwater systems due to several factors such as storage and remobilization from soil and unsaturated zone, limited or absence of degradation, sorption in saturated zones, or to continuing illegal applications. In order to address this problem and to determine triazine distribution in the saturated zone, their occurrence is investigated in the light of the aquifer hydrodynamic on the basis of a geochemical approach using groundwater dating tracers ( 3 H/ 3 He). In this study, atrazine, simazine, terbuthylazine, deethylatrazine, deisopropylatrazine, and deethylterbuthylazine are measured in 66 samples collected between 2011 and 2013 from 21 sampling points, on the Vistrenque shallow alluvial aquifer (southern France), covered by a major agricultural land use. The frequencies of quantification range from 100 to 56 % for simazine and atrazine, respectively (LQ = 1 ng L -1 ). Total triazine concentrations vary between 15 and 350 ng L -1 and show three different patterns with depth below the water table: (1) low concentrations independent of depth but related to water origin, (2) an increase in concentrations with depth in the aquifer related to groundwater residence time and triazine use prior to their ban, and (3) relatively high concentrations at low depths in the saturated zone more likely related to a slow desorption of these compounds from the soil and unsaturated zone. The triazine attenuation rate varies between 0.3 for waters influenced by surface water infiltration and 4.8 for water showing longer residence times in the aquifer, suggesting an increase in these rates with water residence time in the saturated zone. Increasing triazine concentrations with depth is consistent with a significant decrease in the use of these pesticides for the last 10 years on

  12. Find the weakest link. A comparison between demographic, genetic and demo-genetic metapopulation extinction times

    Directory of Open Access Journals (Sweden)

    Robert Alexandre


    Full Text Available Abstract Background While the ultimate causes of most species extinctions are environmental, environmental constraints have various secondary consequences on evolutionary and ecological processes. The roles of demographic, genetic mechanisms and their interactions in limiting the viabilities of species or populations have stirred much debate and remain difficult to evaluate in the absence of demography-genetics conceptual and technical framework. Here, I computed projected times to metapopulation extinction using (1 a model focusing on the effects of species properties, habitat quality, quantity and temporal variability on the time to demographic extinction; (2 a genetic model focusing on the dynamics of the drift and inbreeding loads under the same species and habitat constraints; (3 a demo-genetic model accounting for demographic-genetic processes and feedbacks. Results Results indicate that a given population may have a high demographic, but low genetic viability or vice versa; and whether genetic or demographic aspects will be the most limiting to overall viability depends on the constraints faced by the species (e.g., reduction of habitat quantity or quality. As a consequence, depending on metapopulation or species characteristics, incorporating genetic considerations to demographically-based viability assessments may either moderately or severely reduce the persistence time. On the other hand, purely genetically-based estimates of species viability may either underestimate (by neglecting demo-genetic interactions or overestimate (by neglecting the demographic resilience true viability. Conclusion Unbiased assessments of the viabilities of species may only be obtained by identifying and considering the most limiting processes (i.e., demography or genetics, or, preferentially, by integrating them.

  13. Aging and Network Properties: Stability Over Time and Links with Learning during Working Memory Training

    Directory of Open Access Journals (Sweden)

    Alexandru D. Iordan


    Full Text Available Growing evidence suggests that healthy aging affects the configuration of large-scale functional brain networks. This includes reducing network modularity and local efficiency. However, the stability of these effects over time and their potential role in learning remain poorly understood. The goal of the present study was to further clarify previously reported age effects on “resting-state” networks, to test their reliability over time, and to assess their relation to subsequent learning during training. Resting-state fMRI data from 23 young (YA and 20 older adults (OA were acquired in 2 sessions 2 weeks apart. Graph-theoretic analyses identified both consistencies in network structure and differences in module composition between YA and OA, suggesting topological changes and less stability of functional network configuration with aging. Brain-wide, OA showed lower modularity and local efficiency compared to YA, consistent with the idea of age-related functional dedifferentiation, and these effects were replicable over time. At the level of individual networks, OA consistently showed greater participation and lower local efficiency and within-network connectivity in the cingulo-opercular network, as well as lower intra-network connectivity in the default-mode network and greater participation of the somato-sensorimotor network, suggesting age-related differential effects at the level of specialized brain modules. Finally, brain-wide network properties showed associations, albeit limited, with learning rates, as assessed with 10 days of computerized working memory training administered after the resting-state sessions, suggesting that baseline network configuration may influence subsequent learning outcomes. Identification of neural mechanisms associated with learning-induced plasticity is important for further clarifying whether and how such changes predict the magnitude and maintenance of training gains, as well as the extent and limits of

  14. On H∞ Fault Estimator Design for Linear Discrete Time-Varying Systems under Unreliable Communication Link

    Directory of Open Access Journals (Sweden)

    Yueyang Li


    Full Text Available This paper investigates the H∞ fixed-lag fault estimator design for linear discrete time-varying (LDTV systems with intermittent measurements, which is described by a Bernoulli distributed random variable. Through constructing a novel partially equivalent dynamic system, the fault estimator design is converted into a deterministic quadratic minimization problem. By applying the innovation reorganization technique and the projection formula in Krein space, a necessary and sufficient condition is obtained for the existence of the estimator. The parameter matrices of the estimator are derived by recursively solving two standard Riccati equations. An illustrative example is provided to show the effectiveness and applicability of the proposed algorithm.

  15. The variability in Oxford hip and knee scores in the preoperative period: is there an ideal time to score? (United States)

    Quah, C; Holmes, D; Khan, T; Cockshott, S; Lewis, J; Stephen, A


    Background All NHS-funded providers are required to collect and report patient-reported outcome measures for hip and knee arthroplasty. Although there are established guidelines for timing such measures following arthroplasty, there are no specific time-points for collection in the preoperative period. The primary aim of this study was to identify whether there was a significant amount of variability in the Oxford hip and knee scores prior to surgical intervention when completed in the outpatient clinic at the time of listing for arthroplasty or when completed at the preoperative assessment clinic. Methods A prospective cohort study of patients listed for primary hip or knee arthroplasty was conducted. Patients were asked to fill in a preoperative Oxford score in the outpatient clinic at the time of listing. They were then invited to fill in the official outcome measures questionnaire at the preoperative assessment clinic. The postoperative Oxford score was then completed when the patient was seen again at their postoperative follow up in clinic. Results Of the total of 109 patients included in this study period, there were 18 (17%) who had a worse score of 4 or more points difference and 43 (39.4%) who had an improvement of 4 or more points difference when the scores were compared between time of listing at the outpatient and at the preoperative assessment clinic. There was a statistically significant difference (P = 0.0054) in the mean Oxford scores. Conclusions The results of our study suggest that there should be standardisation of timing for completing the preoperative patient-reported outcome measures.

  16. Real-time 2.5  Gbit/s spatial circuit switching on W-band wireless links

    DEFF Research Database (Denmark)

    Rodríguez, Sebastián; Morales Vicente, Alvaro; Gallardo, Omar


    A spatial circuit switching system based on a beam steering application for W-band wireless links is proposed and experimentally demonstrated. The system enables two simultaneous transmissions of a 2.5 Gbit∕s data signal over a carrier of 81 GHz, while allowing the receiver to dynamically switch...... between them. The performance of the system is tested with the real-time measurements of the BER, achieving values below the FEC limit for 7% of overhead and serving to prove the viability of wireless spatial circuit switching in the next generation of wireless access networks....

  17. The real-time link between person perception and action: brain potential evidence for dynamic continuity. (United States)

    Freeman, Jonathan B; Ambady, Nalini; Midgley, Katherine J; Holcomb, Phillip J


    Using event-related potentials, we investigated how the brain extracts information from another's face and translates it into relevant action in real time. In Study 1, participants made between-hand sex categorizations of sex-typical and sex-atypical faces. Sex-atypical faces evoked negativity between 250 and 550 ms (N300/N400 effects), reflecting the integration of accumulating sex-category knowledge into a coherent sex-category interpretation. Additionally, the lateralized readiness potential revealed that the motor cortex began preparing for a correct hand response while social category knowledge was still gradually evolving in parallel. In Study 2, participants made between-hand eye-color categorizations as part of go/no-go trials that were contingent on a target's sex. On no-go trials, although the hand did not actually move, information about eye color partially prepared the motor cortex to move the hand before perception of sex had finalized. Together, these findings demonstrate the dynamic continuity between person perception and action, such that ongoing results from face processing are immediately and continuously cascaded into the motor system over time. The preparation of action begins based on tentative perceptions of another's face before perceivers have finished interpreting what they just saw. © 2010 Psychology Press, an imprint of the Taylor & Francis Group, an Informa business

  18. On the link between oil price and exchange rate: A time-varying VAR parameter approach

    International Nuclear Information System (INIS)

    Bremond, Vincent; Razafindrabe, Tovonony; Hache, Emmanuel


    The aim of this paper is to study the relationship between the effective exchange rate of the dollar and the oil price dynamics from 1976 to 2013. In this context, we propose to explore the economic literature dedicated to financial channels factors (exchange rate, monetary policy, and international liquidity) that could affect the oil price dynamics. In addition to oil prices and the effective exchange rate of the dollar, we use the dry cargo index as a proxy for the real economic activity and prices for precious and industrial raw materials. Using a Bayesian time-varying parameter vector auto-regressive estimation, our main results show that the US Dollar effective exchange rate elasticity of the crude oil prices is not constant across the time and remains negative from 1989. It then highlights that a depreciation of the effective exchange rate of the dollar leads to an increase of the crude oil prices. Our paper also demonstrates the growing influence of financial and commodities markets development upon the global economy. (authors)

  19. Revealing the timing of ocean stratification using remotely-sensed ocean fronts: links with marine predators (United States)

    Miller, P. I.; Loveday, B. R.


    Stratification is of critical importance to the mixing and productivity of the ocean, though currently it can only be measured using in situ sampling, profiling buoys or underwater autonomous vehicles. Stratification is understood to affect the surface aggregation of pelagic fish and hence the foraging behaviour and distribution of their predators such as seabirds and cetaceans. Satellite Earth observation sensors cannot directly detect stratification, but can observe surface features related to the presence of stratification, for example shelf-sea fronts that separate tidally-mixed water from seasonally stratified water. This presentation describes a novel algorithm that accumulates evidence for stratification from a sequence of oceanic front maps, and in certain regions can reveal the timing of the seasonal onset and breakdown of stratification. Initial comparisons will be made with seabird locations acquired through GPS tagging. If successful, a remotely-sensed stratification timing index would augment the ocean front metrics already developed at PML, that have been applied in over 20 journal articles relating marine predators to ocean fronts. The figure below shows a preliminary remotely-sensed 'stratification' index, for 25-31 Jul. 2010, where red indicates water with stronger evidence for stratification.

  20. Trends, causes and timing of 30-day readmissions after hospitalization for heart failure: 11-year population-based analysis with linked data. (United States)

    Fernandez-Gasso, Lucía; Hernando-Arizaleta, Lauro; Palomar-Rodríguez, Joaquín A; Abellán-Pérez, M Victoria; Pascual-Figal, Domingo A


    Reliable data are necessary if the burden of early readmissions following hospitalization for heart failure (HF) is to be addressed. We studied unplanned 30-day readmissions, their causes and timing over an 11-year period, using population-based linked data. All hospitalizations from 2003 to 2013 were analyzed by using administrative linked data based on the Minimum Basic Set discharge registry of the Department of Health (Region of Murcia, Spain). Index hospitalizations with HF as principal diagnosis (n=27,581) were identified. Transfers between centers were merged into one discharge. Readmissions were defined as unplanned admissions to any hospital within 30-days after discharge. In the 2003-2013 period, 30-day readmission rates had a relative mean annual growth of +1.36%, increasing from 17.6% to 22.1%, with similar trends for cardiovascular and non-cardiovascular causes. The figure of 22.1% decreased to 19.8% when only same-hospital readmissions were considered. Most readmissions were due to cardiovascular causes (60%), HF being the most common single cause (34%). The timing of readmission shows an early peak on the fourth day post discharge (+13.29%) due to causes other than HF, followed by a gradual decline (-3.32%); readmission for HF decreased steadily from the first day (-2.22%). Readmission for HF (12.7%) or non-cardiovascular causes (13.3%) had higher in-hospital mortality rates than the index hospitalization (9.2%, p<0.001). Age and comorbidity burden were the main predictors of any readmission, but the performance of a predictive model was poor. These findings support the need for population-based strategies to reduce the burden of early-unplanned readmissions. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Real-time product attribute control to manufacture antibodies with defined N-linked glycan levels. (United States)

    Zupke, Craig; Brady, Lowell J; Slade, Peter G; Clark, Philip; Caspary, R Guy; Livingston, Brittney; Taylor, Lisa; Bigham, Kyle; Morris, Arvia E; Bailey, Robert W


    Pressures for cost-effective new therapies and an increased emphasis on emerging markets require technological advancements and a flexible future manufacturing network for the production of biologic medicines. The safety and efficacy of a product is crucial, and consistent product quality is an essential feature of any therapeutic manufacturing process. The active control of product quality in a typical biologic process is challenging because of measurement lags and nonlinearities present in the system. The current study uses nonlinear model predictive control to maintain a critical product quality attribute at a predetermined value during pilot scale manufacturing operations. This approach to product quality control ensures a more consistent product for patients, enables greater manufacturing efficiency, and eliminates the need for extensive process characterization by providing direct measures of critical product quality attributes for real time release of drug product. © 2015 American Institute of Chemical Engineers.

  2. One period coupon bond valuation with revised first passage time approach and the application in Indonesian corporate bond (United States)

    Maruddani, Di Asih I.; Rosadi, Dedi; Gunardic, Abdurakhman


    The value of a corporate bond is conventionally expressed in terms of zero coupon bond. In practice, the most common form of debt instrument is coupon bond and allows early default before maturity as safety covenant for the bondholder. This paper study valuation for one period coupon bond, a coupon bond that only give one time coupon at the bond period. It assumes that the model give bondholder the right to reorganize a firm if its value falls below a given barrier. Revised first passage time approach is applied for default time rule. As a result, formulas of equity, liability, and probability of default is derived for this specified model. Straightforward integration under risk neutral pricing is used for deriving those formulas. For the application, bond of Bank Rakyat Indonesia (BRI) as one of the largest bank in Indonesia is analyzed. R computing show that value of the equity is IDR 453.724.549.000.000, the liability is IDR 2.657.394.000.000, and the probability if default is 5.645305E-47 %.

  3. Period variations in pulsating X-ray sources. I. Accretion flow parameters and neutron star structure from timing observations

    International Nuclear Information System (INIS)

    Lamb, F.K.; Pines, D.; Shaham, J.


    We show that valuable information about both accretion flows and neutron star structure can be obtained from X-ray timing observations of period variations in pulsating sources. Such variations can result from variations in the accretion flow, or from internal torque variations, associated with oscillations of the fluid core or the unpinning of vortices in the inner crust. We develop a statistical description of torque variations in terms of noise processes, indicate how the applicability of such a description may be tested observationally, and show how it may be used to determine from observation both the properties of accretion flows and the internal structure of neutron stars, including the relative inertial moments of the crust and superfluid neutron core, the crust-core coupling time, and the frequencies of any low-frequency internal collective modes. Particular attention is paid to the physical origin of spin-down episodes; it is shown that usyc episodes may result either from external torque reversals or from internal torque variations.With the aid of the statistical description, the response of the star to torque fluctuations is calculated for three stellar models: (i) a completely rigid star; (ii) a two-component star; and (iii) a two-component star with a finite-frequency internal mode, such as the Tkachenko mode of a rotating neutron superfluid. Our calculations show that fluctuating torques could account for the period the period variations and spin-down episodes observed in Her X-1 and Cen X-3, including the large spin-down event observed in the latter source during 1972 September-October. The torque noise strengths inferred from current timing observations using the simple two-component models are shown to be consistent with those to be expected from fluctuations in accretion flows onto magnetic neutron stars

  4. Construction and properties of a topological index for periodically driven time-reversal invariant 2D crystals

    Directory of Open Access Journals (Sweden)

    D. Carpentier


    Full Text Available We present mathematical details of the construction of a topological invariant for periodically driven two-dimensional lattice systems with time-reversal symmetry and quasienergy gaps, which was proposed recently by some of us. The invariant is represented by a gap-dependent Z2-valued index that is simply related to the Kane–Mele invariants of quasienergy bands but contains an extra information. As a byproduct, we prove new expressions for the two-dimensional Kane–Mele invariant relating the latter to Wess–Zumino amplitudes and the boundary gauge anomaly.

  5. A low power CMOS 3.3 Gbps continuous-time adaptive equalizer for serial link

    International Nuclear Information System (INIS)

    Ju Hao; Zhou Yumei; Zhao Jianzhong


    This paper describes using a high-speed continuous-time analog adaptive equalizer as the front-end of a receiver for a high-speed serial interface, which is compliant with many serial communication specifications such as USB2.0, PCI-E2.0 and Rapid IO. The low and high frequency loops are merged to decrease the effect of delay between the two paths, in addition, the infinite input impedance facilitates the cascade stages in order to improve the high frequency boosting gain. The implemented circuit architecture could facilitate the wide frequency range from 1 to 3.3 Gbps with different length FR4-PCB traces, which brings as much as 25 dB loss. The replica control circuits are injected to provide a convenient way to regulate common-mode voltage for full differential operation. In addition, AC coupling is adopted to suppress the common input from the forward stage. A prototype chip was fabricated in 0.18-μm 1P6M mixed-signal CMOS technology. The actual area is 0.6 x 0.57 mm 2 and the analog equalizer operates up to 3.3 Gbps over FR4-PCB trace with 25 dB loss. The overall power dissipation is approximately 23.4 mW. (semiconductor integrated circuits)

  6. A low power CMOS 3.3 Gbps continuous-time adaptive equalizer for serial link (United States)

    Hao, Ju; Yumei, Zhou; Jianzhong, Zhao


    This paper describes using a high-speed continuous-time analog adaptive equalizer as the front-end of a receiver for a high-speed serial interface, which is compliant with many serial communication specifications such as USB2.0, PCI-E2.0 and Rapid IO. The low and high frequency loops are merged to decrease the effect of delay between the two paths, in addition, the infinite input impedance facilitates the cascade stages in order to improve the high frequency boosting gain. The implemented circuit architecture could facilitate the wide frequency range from 1 to 3.3 Gbps with different length FR4-PCB traces, which brings as much as 25 dB loss. The replica control circuits are injected to provide a convenient way to regulate common-mode voltage for full differential operation. In addition, AC coupling is adopted to suppress the common input from the forward stage. A prototype chip was fabricated in 0.18-μm 1P6M mixed-signal CMOS technology. The actual area is 0.6 × 0.57 mm2 and the analog equalizer operates up to 3.3 Gbps over FR4-PCB trace with 25 dB loss. The overall power dissipation is approximately 23.4 mW.

  7. Investigating the link between fish community structure and environmental state in deep-time (United States)

    Sibert, E. C.


    In the modern ocean, a bottom-up ecological viewpoint posits that the composition of plankton communities is often a function of ambient oceanographic conditions, including nutrient concentrations and water temperature. Thus, certain plankton species or communities can be associated with specific oceanographic conditions, giving them potential as carriers of paleoceanographic information. Furthermore, consumer groups, such as fish, depend on the structure and composition of these plankton, and therefore different plankton communities will support different types of fish. In addition, fish have their own physiological constraints for surviving in particular environments, such as oxygen demand, and metabolic rate, causing certain clades to be selectively associated with different water mass characteristics. Thus, the relative or absolute abundances of different fish species or groups could shed light on shifting oxygen concentrations, temperature, or primary productivity in the past. To assess whether fish communities have sufficient environmental control to provide paleoceanographic insights, I use a variety of morphological, phylogenetic, and ecological statistical approaches, to correlate modern fish communities from around the world with environmental variables. I then apply these principles to a series of ichthyolith assemblages from the Cretaceous and Cenozoic, across both space and time, to assess whether fish community composition, abundance, or other characteristics can be predictive of ocean temperature or export productivity. I find that while the abundance of fish fossils in deep-sea cores is often, though not always, correlated with certain export production and temperature proxies, community composition appears to vary independently of these variables on long timescales, driven more by evolutionary processes. However, there are distinct differences in contemporary communities in different locations, suggesting that there is potential in using fish

  8. Spectral-Timing Analysis of Kilohetrz Quasi-Periodic Osciallations in Neutron Star Low-Mass X-ray Binaries (United States)

    Cackett, Edward; Troyer, Jon; Peille, Philippe; Barret, Didier


    Kilohertz quasi-periodic oscillations or kHz QPOs are intensity variations that occur in the X-ray band observed in neutron star low-mass X-ray binary (LMXB) systems. In such systems, matter is transferred from a secondary low-mass star to a neutron star via the process of accretion. kHz QPOs occur on the timescale of the inner accretion flow and may carry signatures of the physics of strong gravity (c2 ~ GM/R) and possibly clues to constraining the neutron star equation of state (EOS). Both the timing behavior of kHz QPOs and the time-averaged spectra of these systems have been studied extensively. No model derived from these techniques has been able to illuminate the origin of kHz QPOs. Spectral-timing is an analysis technique that can be used to derive information about the nature of physical processes occurring within the accretion flow on the timescale of the kHz QPO. To date, kHz QPOs of (4) neutron star LMXB systems have been studied with spectral-timing techniques. We present a comprehensive study of spectral-timing products of kHz QPOs from systems where data is available in the RXTE archive to demonstrate the promise of this technique to gain insights regarding the origin of kHz QPOs. Using data averaged over the entire RXTE archive, we show correlated time-lags as a function of QPO frequency and energy, as well as energy-dependent covariance spectra for the various LMXB systems where spectral-timing analysis is possible. We find similar trends in all average spectral-timing products for the objects studied. This suggests a common origin of kHz QPOs.

  9. Using Computer Techniques To Predict OPEC Oil Prices For Period 2000 To 2015 By Time-Series Methods

    Directory of Open Access Journals (Sweden)

    Mohammad Esmail Ahmad


    Full Text Available The instability in the world and OPEC oil process results from many factors through a long time. The problems can be summarized as that the oil exports dont constitute a large share of N.I. only but it also makes up most of the saving of the oil states. The oil prices affect their market through the interaction of supply and demand forces of oil. The research hypothesis states that the movement of oil prices caused shocks crises and economic problems. These shocks happen due to changes in oil prices need to make a prediction within the framework of economic planning in a short run period in order to avoid shocks through using computer techniques by time series models.

  10. Calcifying discopathy in infancy in the cervical spine: Evaluation of vertebral alterations over a period of time

    Energy Technology Data Exchange (ETDEWEB)

    Urso, S; Colajacomo, M; Migliorini, A; Fassari, F M


    CDI in the cervical spine has already been observed and described by many authors, as a well-defined clinico-radiological syndrome with a benign course. The clinical picture is composed of: pain and functional limitation, sometimes with a stiff neck, more rarely slight fever, increase of the erythrocyte sedimentation rate or leukocytosis. The radiographic picture consists of the association of morphological and structural alterations of vertebral bodies adjacent to one or more disc calcifications usually centrally sited, sometimes associated with anterior or posterior herniations. On the basis of the observation of 7 patients, in the 15-year-old range, the authors propose to evaluate the changes of both the vertebral bodies and the discs involved in the disease over a period of time. The repetition of even modest alterations, that persist in time, testify to the involvement of the vertebral growth perhaps, more than the discal alterations connected with the calcification.

  11. Time trends for prostate cancer mortality in Brazil and its geographic regions: An age-period-cohort analysis. (United States)

    Braga, Sonia Faria Mendes; de Souza, Mirian Carvalho; Cherchiglia, Mariangela Leal


    In the 1980s, an increase in mortality rates for prostate cancer was observed in North America and developed European countries. In the 1990s, however, mortality rates decreased for these countries, an outcome related to early detection of the disease. Conversely, an upward trend in mortality rates was observed in Brazil. This study describe the trends in mortality for prostate cancer in Brazil and geographic regions (North, Northeast, South, Southeast, and Central-West) between 1980 until 2014 and analyze the influence of age, period, and cohort effects on mortality rates. This time-series study used data from the Mortality Information System (SIM) and population data from Brazilian Institute for Geography and Statistics (IBGE). The effects on mortality rates were examined using age-period-cohort (APC) models. Crude and standardized mortality rates showed an upward trend for Brazil and its regions more than 2-fold the last 30 years. Age effects showed an increased risk of death in all regions. Period effects showed a higher risk of death in the finals periods for the North and Northeast. Cohort effects showed risk of death was higher for younger than older generations in Brazil and regions, mainly Northeast (RR Adjusted =3.12, 95% CI 1.29-1.41; RR Adjusted =0.28, 95% CI 0.26-0.30, respectively). The increase in prostate cancer mortality rates in Brazil and its regions was mainly due to population aging. The differences in mortality rates and APC effects between regions are related to demographic differences and access of health services across the country. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Age, time period, and birth cohort differences in self-esteem: Reexamining a cohort-sequential longitudinal study. (United States)

    Twenge, Jean M; Carter, Nathan T; Campbell, W Keith


    Orth, Trzesniewski, and Robins (2010) concluded that the nationally representative Americans' Changing Lives (ACL) cohort-sequential study demonstrated moderate to large age differences in self-esteem, and no birth cohort (generational) differences in the age trajectory. In a reanalysis of these data using 2 different statistical techniques, we find significant increases in self-esteem that could be attributed to birth cohort or time period. First, hierarchical linear modeling analyses with birth cohort as a continuous variable (vs. the multiple group formulation used by Orth et al.) find that birth cohort has a measurable influence on self-esteem through its interaction with age. Participants born in later years (e.g., 1960) were higher in self-esteem and were more likely to increase in self-esteem as they aged than participants born in earlier years (e.g., 1920). However, the estimated age trajectory up to age 60 is similar in Orth et al.'s results and in the results from our analyses including cohort. Second, comparing ACL respondents of the same age in 1986 versus 2002 (a time-lag design) yields significant birth cohort differences in self-esteem, with 2002 participants of the same age higher in self-esteem than those in 1986. Combined with some previous studies finding significant increases in self-esteem and positive self-views over time, these results suggest that cultural change in the form of cohort and time period cannot be ignored as influences in cross-sectional and longitudinal studies. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  13. Bacterial spectrum and susceptibility patterns of pathogens in adult febrile neutropenic patients: a comparison between two time periods

    International Nuclear Information System (INIS)

    Zahid, K.F.; Hafeez, H.; Afzal, A.


    The aim of this study was to study trends in bacterial spectrum and susceptibility patterns of pathogens in adult febrile neutropenic patients during two time periods. We retrospectively reviewed the medical records of 379 adult oncology patients admitted with chemotherapy induced febrile neutropenia at our institute during years 2003 and 2006. A total of 151 organisms were isolated during the two calendar years. Gram negative bacteria accounted for 57.6% of organisms, while gram positive organisms accounted for 42.3% of the total isolates. The most common organisms were: Escherichia coli (23.1%), Staphylococcus epidermidis (13.9%), Pseudomonas aeruginosa (12.5%) and Staphylococcus aureus (7.9%). The number of gram positive isolates showed an increase from 35% in 2003 to 47.2% in 2006 (p=0.13). During each calendar year, Staphylococcus epidermidis and Staphylococcus aureus were 100% susceptible to vancomycin and 33% strains of Staphylococcus aureus were methicillin resistant. Escherichia coli and Pseudomonas aeruginosa strains were highly sensitive to piperacillin/tazobactam and amikacin during both time periods. Resistance of Pseudomonas aeruginosa strains to ciprofloxacin increased from 0% in 2003 to 50% in 2006 (p=0.03). Gram negative organisms are the predominant organisms in adult febrile neutropenic patients at our institute. Initial empirical therapy with piperacillin/tazobactam seems appropriate to cover most gram negative pathogens while vancomycin to be added for suspected gram positive infections. During the two calendar years resistance of Pseudomonas aeruginosa strains to ciprofloxacin has significantly increased. (author)

  14. A Time Series Analysis of Macroeconomic Determinants of Corporate Births in Romania in the period 2008-2013

    Directory of Open Access Journals (Sweden)

    Marușa Beca


    Full Text Available In this article, we studied the relationship between macroeconomic factors and the observed corporate births for the Romanian economy through the Autoregressive Distributed Lags Model (ADL. We performed a time series analysis that uses monthly data for the period January 2008 – December 2013 in order to establish the impact of the fiscal and monetary policy adopted by the Romanian government in times of economic crisis on the firms’ demography. The corporate birth rate is an endogenous variable in a linear function model with five exogenous macroeconomic variables such as the CPI, the loans ratio to GDP, the FDI, the long term interest rate, tax rate to GDP and the lags of the dependent variable. The main finding is that the variance of the corporate birth rate variable is negatively correlated with the variances of CPI in the current month and the interest rate two months lagged. We also determined that the variance of the dependent variable was positively correlated with the variances of the loans rate two months lagged, tax rate four months ago and FDI two months lagged and FDI in the current period.

  15. Period and phase comparisons of near-decadal oscillations in solar, geomagnetic, and cosmic ray time series (United States)

    Juckett, David A.


    A more complete understanding of the periodic dynamics of the Sun requires continued exploration of non-11-year oscillations in addition to the benchmark 11-year sunspot cycle. In this regard, several solar, geomagnetic, and cosmic ray time series were examined to identify common spectral components and their relative phase relationships. Several non-11-year oscillations were identified within the near-decadal range with periods of ~8, 10, 12, 15, 18, 22, and 29 years. To test whether these frequency components were simply low-level noise or were related to a common source, the phases were extracted for each component in each series. The phases were nearly identical across the solar and geomagnetic series, while the corresponding components in four cosmic ray surrogate series exhibited inverted phases, similar to the known phase relationship with the 11-year sunspot cycle. Cluster analysis revealed that this pattern was unlikely to occur by chance. It was concluded that many non-11-year oscillations truly exist in the solar dynamical environment and that these contribute to the complex variations observed in geomagnetic and cosmic ray time series. Using the different energy sensitivities of the four cosmic ray surrogate series, a preliminary indication of the relative intensities of the various solar-induced oscillations was observed. It provides evidence that many of the non-11-year oscillations result from weak interplanetary magnetic field/solar wind oscillations that originate from corresponding variations in the open-field regions of the Sun.

  16. Probability of Loss of Assured Safety in Systems with Multiple Time-Dependent Failure Modes: Incorporation of Delayed Link Failure in the Presence of Aleatory Uncertainty.

    Energy Technology Data Exchange (ETDEWEB)

    Helton, Jon C. [Arizona State Univ., Tempe, AZ (United States); Brooks, Dusty Marie [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Sallaberry, Cedric Jean-Marie. [Engineering Mechanics Corp. of Columbus, OH (United States)


    Probability of loss of assured safety (PLOAS) is modeled for weak link (WL)/strong link (SL) systems in which one or more WLs or SLs could potentially degrade into a precursor condition to link failure that will be followed by an actual failure after some amount of elapsed time. The following topics are considered: (i) Definition of precursor occurrence time cumulative distribution functions (CDFs) for individual WLs and SLs, (ii) Formal representation of PLOAS with constant delay times, (iii) Approximation and illustration of PLOAS with constant delay times, (iv) Formal representation of PLOAS with aleatory uncertainty in delay times, (v) Approximation and illustration of PLOAS with aleatory uncertainty in delay times, (vi) Formal representation of PLOAS with delay times defined by functions of link properties at occurrence times for failure precursors, (vii) Approximation and illustration of PLOAS with delay times defined by functions of link properties at occurrence times for failure precursors, and (viii) Procedures for the verification of PLOAS calculations for the three indicated definitions of delayed link failure.

  17. Leisure activities are linked to mental health benefits by providing time structure: comparing employed, unemployed and homemakers. (United States)

    Goodman, William K; Geiger, Ashley M; Wolf, Jutta M


    Unemployment has consistently been linked to negative mental health outcomes, emphasising the need to characterise the underlying mechanisms. The current study aimed at testing whether compared with other employment groups, fewer leisure activities observed in unemployment may contribute to elevated risk for negative mental health via loss of time structure. Depressive symptoms (Center for Epidemiologic Studies Depression), leisure activities (exercise, self-focused, social), and time structure (Time Structure Questionnaire (TSQ)) were assessed cross-sectionally in 406 participants (unemployed=155, employed=140, homemakers=111) recruited through Amazon Mechanical Turk. Controlling for gender and age, structural equation modelling revealed time structure partially (employed, homemakers) and fully (unemployed) mediated the relationship between leisure activities and depressive symptoms. With the exception of differential effects for structured routines, all other TSQ factors (sense of purpose, present orientation, effective organisation and persistence) contributed significantly to all models. These findings support the idea that especially for the unemployed, leisure activities impose their mental health benefits through increasing individuals' perception of spending their time effectively. Social leisure activities that provide a sense of daily structure may thereby be a particularly promising low-cost intervention to improve mental health in this population. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to

  18. TRACEing Last Glacial Period (25-80 ka b2k) tephra horizons within North Atlantic marine cores and exploring links to the Greenland ice-cores (United States)

    Abbott, P. M.; Davies, S. M.; Griggs, A. J.; Bourne, A. J.; Cook, E.; Pearce, N. J. G.; Austin, W. E. N.; Chapman, M.; Hall, I. R.; Purcell, C. S.; Scourse, J. D.; Rasmussen, T. L.


    Tephrochronology is a powerful technique for the correlation and synchronisation of disparate palaeoclimatic records from different depositional environments and has considerable potential for testing climatic phasing. For example, the relative timing of atmospheric and marine changes caused by the abrupt climatic events that punctuated the last glacial period within the North Atlantic region. Here we report on efforts to establish a framework of tephra horizons within North Atlantic marine sequences that can correlate these records and if traced in the Greenland ice-cores can act as isochronous tie-lines. Investigations have been conducted on a network of marine cores from a number of sites across the North Atlantic. Tephra horizons have been identified using cryptotephra extraction techniques more commonly applied to the study of terrestrial sequences. There are two main challenges with assessing cryptotephras in the glacial North Atlantic; i) determining the transportation processes and ii) assessing the influence of secondary reworking processes and the stratigraphic integrity of the isochrons. These processes and their influence are investigated for each cryptotephra using shard size variations, major element heterogeneity and co-variance of IRD input for some cores. Numerous Icelandic cryptophras have been successfully identified in the marine records and we will discuss the integration of a number of these with an isochronous nature into a marine tephra framework and how potential correlations to the Greenland ice-core tephra framework are determined. Spatial patterns in the nature of tephra records that are emerging from the core network will be highlighted to outline some of the key areas that could be explored in the future. In addition, the synchronisation of multiple North Atlantic records to the Greenland ice-cores using the North Atlantic Ash Zone II to test the synchroneity of an abrupt cooling in the North Atlantic will be discussed.

  19. Time trend and age-period-cohort effect on kidney cancer mortality in Europe, 1981–2000

    Directory of Open Access Journals (Sweden)

    López-Abente Gonzalo


    Full Text Available Abstract Background The incorporation of diagnostic and therapeutic improvements, as well as the different smoking patterns, may have had an influence on the observed variability in renal cancer mortality across Europe. This study examined time trends in kidney cancer mortality in fourteen European countries during the last two decades of the 20th century. Methods Kidney cancer deaths and population estimates for each country during the period 1981–2000 were drawn from the World Health Organization Mortality Database. Age- and period-adjusted mortality rates, as well as annual percentage changes in age-adjusted mortality rates, were calculated for each country and geographical region. Log-linear Poisson models were also fitted to study the effect of age, death period, and birth cohort on kidney cancer mortality rates within each country. Results For men, the overall standardized kidney cancer mortality rates in the eastern, western, and northern European countries were 20, 25, and 53% higher than those for the southern European countries, respectively. However, age-adjusted mortality rates showed a significant annual decrease of -0.7% in the north of Europe, a moderate rise of 0.7% in the west, and substantial increases of 1.4% in the south and 2.0% in the east. This trend was similar among women, but with lower mortality rates. Age-period-cohort models showed three different birth-cohort patterns for both men and women: a decrease in mortality trend for those generations born after 1920 in the Nordic countries, a similar but lagged decline for cohorts born after 1930 in western and southern European countries, and a continuous increase throughout all birth cohorts in eastern Europe. Similar but more heterogeneous regional patterns were observed for period effects. Conclusion Kidney cancer mortality trends in Europe showed a clear north-south pattern, with high rates on a downward trend in the north, intermediate rates on a more marked rising

  20. Hydraulic residence time and iron removal in a wetland receiving ferruginous mine water over a 4 year period from commissioning. (United States)

    Kusin, F M; Jarvis, A P; Gandy, C J


    Analysis of residence time distribution (RTD) has been conducted for the UK Coal Authority's mine water treatment wetland at Lambley, Northumberland, to determine the hydraulic performance of the wetland over a period of approximately 4 years since site commissioning. The wetland RTD was evaluated in accordance with moment analysis and modelled based on a tanks-in-series (TIS) model to yield the hydraulic characteristics of system performance. Greater hydraulic performance was seen during the second site monitoring after 21 months of site operation i.e. longer hydraulic residence time to reflect overall system hydraulic efficiency, compared to wetland performance during its early operation. Further monitoring of residence time during the third year of wetland operation indicated a slight reduction in hydraulic residence time, thus a lower system hydraulic efficiency. In contrast, performance during the fourth year of wetland operation exhibited an improved overall system hydraulic efficiency, suggesting the influence of reed growth over the lifetime of such systems on hydraulic performance. Interestingly, the same pattern was found for iron (which is the primary pollutant of concern in ferruginous mine waters) removal efficiency of the wetland system from the second to fourth year of wetland operation. This may therefore, reflect the maturity of reeds for maintaining efficient flow distribution across the wetland to retain a longer residence time and significant fractions of water involved to enhance the extent of treatment received for iron attenuation. Further monitoring will be conducted to establish whether such performance is maintained, or whether efficiency decreases over time due to accumulation of dead plant material within the wetland cells.

  1. Changes in the use practitioner-based complementary and alternative medicine over time in Canada: Cohort and period effects.

    Directory of Open Access Journals (Sweden)

    Mayilee Canizares

    Full Text Available The use of complementary and alternative medicine (CAM is growing. However the factors contributing to changes over time and to birth cohort differences in CAM use are not well understood.We used data from 10186 participants, who were aged 20-69 years at the first cycle of data collection in the longitudinal component of the Canadian National Population Health Survey (1994/95-2010/11. We examined chiropractic and other practitioner-based CAM use with a focus on five birth cohorts: pre-World War II (born 1925-1934; World War II (born 1935-1944; older baby boomers (born 1945-1954; younger baby boomers (born 1955-1964; and Gen Xers (born 1965-1974. The survey collected data every two years on predisposing (e.g., sex, education, enabling (e.g., income, behavior-related factors (e.g., obesity, need (e.g., chronic conditions, and use of conventional care (primary care and specialists.The findings suggest that, at corresponding ages, more recent cohorts reported greater CAM (OR = 25.9, 95% CI: 20.0; 33.6 for Gen Xers vs. pre-World War and chiropractic use than their predecessors (OR = 2.2, 95% CI: 1.7; 2.8 for Gen Xers vs. pre-World War. There was also a secular trend of increasing CAM use, but not chiropractic use, over time (period effect across all ages. Factors associated with cohort differences were different for CAM and chiropractic use. Cohort differences in CAM use were partially related to a period effect of increasing CAM use over time across all ages while cohort differences in chiropractic use were related to the higher prevalence of chronic conditions among recent cohorts. The use of conventional care was positively related to greater CAM use (OR = 1.8, 95% CI: 1.6; 2.0 and chiropractic use (OR = 1.2, 95% CI: 1.1; 1.4 but did not contribute to changes over time or to cohort differences in CAM and chiropractic use.The higher CAM use over time and in recent cohorts could reflect how recent generations are approaching their healthcare needs

  2. Dynamic RSA: Examining parasympathetic regulatory dynamics via vector-autoregressive modeling of time-varying RSA and heart period. (United States)

    Fisher, Aaron J; Reeves, Jonathan W; Chi, Cyrus


    Expanding on recently published methods, the current study presents an approach to estimating the dynamic, regulatory effect of the parasympathetic nervous system on heart period on a moment-to-moment basis. We estimated second-to-second variation in respiratory sinus arrhythmia (RSA) in order to estimate the contemporaneous and time-lagged relationships among RSA, interbeat interval (IBI), and respiration rate via vector autoregression. Moreover, we modeled these relationships at lags of 1 s to 10 s, in order to evaluate the optimal latency for estimating dynamic RSA effects. The IBI (t) on RSA (t-n) regression parameter was extracted from individual models as an operationalization of the regulatory effect of RSA on IBI-referred to as dynamic RSA (dRSA). Dynamic RSA positively correlated with standard averages of heart rate and negatively correlated with standard averages of RSA. We propose that dRSA reflects the active downregulation of heart period by the parasympathetic nervous system and thus represents a novel metric that provides incremental validity in the measurement of autonomic cardiac control-specifically, a method by which parasympathetic regulatory effects can be measured in process. © 2016 Society for Psychophysiological Research.

  3. Global paths of time-periodic solutions of the Benjamin-Ono equation connecting arbitrary traveling waves

    Energy Technology Data Exchange (ETDEWEB)

    Ambrose, David M.; Wilkening, Jon


    We classify all bifurcations from traveling waves to non-trivial time-periodic solutions of the Benjamin-Ono equation that are predicted by linearization. We use a spectrally accurate numerical continuation method to study several paths of non-trivial solutions beyond the realm of linear theory. These paths are found to either re-connect with a different traveling wave or to blow up. In the latter case, as the bifurcation parameter approaches a critical value, the amplitude of the initial condition grows without bound and the period approaches zero. We propose a conjecture that gives the mapping from one bifurcation to its counterpart on the other side of the path of non-trivial solutions. By experimentation with data fitting, we identify the form of the exact solutions on the path connecting two traveling waves, which represents the Fourier coefficients of the solution as power sums of a finite number of particle positions whose elementary symmetric functions execute simple orbits in the complex plane (circles or epicycles). We then solve a system of algebraic equations to express the unknown constants in the new representation in terms of the mean, a spatial phase, a temporal phase, four integers (enumerating the bifurcation at each end of the path) and one additional bifurcation parameter. We also find examples of interior bifurcations from these paths of already non-trivial solutions, but we do not attempt to analyze their algebraic structure.

  4. Drift Compression and Final Focus for Intense Heavy Ion Beams with Non-periodic, Time-dependent Lattice

    International Nuclear Information System (INIS)

    Hong Qin; Davidson, Ronald C.; Barnard, John J.; Lee, Edward P.


    In the currently envisioned configurations for heavy ion fusion, it is necessary to longitudinally compress the beam bunches by a large factor after the acceleration phase. Because the space-charge force increases as the beam is compressed, the beam size in the transverse direction will increase in a periodic quadrupole lattice. If an active control of the beam size is desired, a larger focusing force is needed to confine the beam in the transverse direction, and a non-periodic quadrupole lattice along the beam path is necessary. In this paper, we describe the design of such a focusing lattice using the transverse envelope equations. A drift compression and final focus lattice should focus the entire beam pulse onto the same focal spot on the target. This is difficult with a fixed lattice, because different slices of the beam may have different perveance and emittance. Four time-dependent magnets are introduced in the upstream of drift compression to focus the entire pulse onto the sam e focal spot. Drift compression and final focusing schemes are developed for a typical heavy ion fusion driver and for the Integrated Beam Experiment (IBX) being designed by the Heavy Ion Fusion Virtual National Laboratory


    Energy Technology Data Exchange (ETDEWEB)

    Dolla, L.; Marque, C.; Seaton, D. B.; Dominique, M.; Berghmans, D.; Cabanas, C.; De Groof, A.; Verdini, A.; West, M. J.; Zhukov, A. N. [Solar-Terrestrial Center of Excellence, Royal Observatory of Belgium, Avenue Circulaire 3, B-1180 Brussels (Belgium); Van Doorsselaere, T. [Centrum voor Plasma-Astrofysica, Department of Mathematics, KULeuven, Celestijnenlaan 200B bus 2400, B-3001 Leuven (Belgium); Schmutz, W. [Physikalisch-Meteorologisches Observatorium Davos, World Radiation Center, Davos Dorf (Switzerland); Zender, J., E-mail: [European Space Agency, ESTEC, Keplerlaan 1, 2201 AZ Noordwijk (Netherlands)


    We report observations of quasi-periodic pulsations (QPPs) during the X2.2 flare of 2011 February 15, observed simultaneously in several wavebands. We focus on fluctuations on timescale 1-30 s and find different time lags between different wavebands. During the impulsive phase, the Reuven Ramaty High Energy Solar Spectroscopic Imager channels in the range 25-100 keV lead all the other channels. They are followed by the Nobeyama RadioPolarimeters at 9 and 17 GHz and the extreme-ultraviolet (EUV) channels of the Euv SpectroPhotometer (ESP) on board the Solar Dynamic Observatory. The zirconium and aluminum filter channels of the Large Yield Radiometer on board the Project for On-Board Autonomy satellite and the soft X-ray (SXR) channel of ESP follow. The largest lags occur in observations from the Geostationary Operational Environmental Satellite, where the channel at 1-8 A leads the 0.5-4 A channel by several seconds. The time lags between the first and last channels is up to Almost-Equal-To 9 s. We identified at least two distinct time intervals during the flare impulsive phase, during which the QPPs were associated with two different sources in the Nobeyama RadioHeliograph at 17 GHz. The radio as well as the hard X-ray channels showed different lags during these two intervals. To our knowledge, this is the first time that time lags are reported between EUV and SXR fluctuations on these timescales. We discuss possible emission mechanisms and interpretations, including flare electron trapping.

  6. An assessment of issues related to determination of time periods required for isolation of high level waste

    International Nuclear Information System (INIS)

    Cohen, J.J.; Daer, G.R.; Smith, C.F.; Vogt, D.K.; Woolfolk, S.W.


    A commonly held perception is that disposal of spent nuclear fuel or high-level waste presents a risk of unprecedented duration. The EPA requires that projected releases of radioactivity be limited for 10,000 years after disposal with the intent that risks from the disposal repository be no greater than those from the uranium ore deposit from which the nuclear fuel was originally extracted. This study reviews issues involved in assessing compliance with the requirement. The determination of compliance is assumption dependent primarily due to uncertainties in dosimetric data, and relative availability of the radioactivity for environmental transport and eventual assimilation by humans. A conclusion of this study is that, in time, a spent fuel disposal repository such as the projected Yucca Mountain Project Facility will become less hazardous than the original ore deposit. Only the time it takes to do so is in question. Depending upon the assumptions selected, this time period could range from a few centuries to hundreds of thousands of years considering only the inherent radiotoxicities. However, if it can be assumed that the spent fuel radioactivity emplaced in a waste repository is less than 1/10 as available for human assimilation than that in a uranium ore deposit, then even under the most pessimistic set of assumptions, the EPA criteria can be considered to be complied with. 24 refs., 5 figs., 2 tabs

  7. Study on mixis potential of rotifer resting eggs ( Brachionus plicatilis) with different collection times and different preservation periods (United States)

    Zhou, Li; Zheng, Yan; Xiang, Jian-Hai


    The present study investigated the possible changes in the mixis potential of rotifer resting eggs produced by a single stock of Brachionus plicatilis and collected and preserved annually from 1985 1998. Several clones derived from each batch of resting eggs were cultured under the same conditions for 21 days. The percentage of clones appearing resting eggs and the average yield of resting eggs produced from each clone were recorded and statistically analyzed to find the differences between the mixis potential of those resting egg batches. Results showed that different batches of resting eggs had different mictic levels among their descendent clones; but no regular relationship was found between the mixis potential of resting eggs and their collection times/preservation periods. Several internal and external factors that might affect the mixis potential of resting eggs were discussed.

  8. Singularity Structure Analysis of the Higher-Dimensional Time-Gated Manakov System: Periodic Excitations and Elastic Scattering

    International Nuclear Information System (INIS)

    Kuetche, Victor Kamgang; Bouetou, Thomas Bouetou; Kofane, Timoleon Crepin


    We investigate the singularity structure analysis of the higher-dimensional time-gated Manakov system referring to the (2+1)-dimensional coupled nonlinear Schroedinger (CNLS) equations, and we show that these equations are Painleve-integrable. By means of the Weiss et al.'s methodology, we show the arbitrariness of the expansion coefficients and the consistency of the truncation corresponding to a special Baecklund transformation (BT) of these CNLS equations. In the wake of such transformation, following the Hirota's formalism, we derive a one-soliton solution. Besides, by using the Zakharov-Shabat (ZS) scheme which provides a general Lax-representation of an evolution system, we show that the (2+1)-dimensional CNLS system under interests is completely integrable. Furthermore, using the arbitrariness of the above coefficients, we unearth and investigate a typical spectrum of periodic coherent structures while depicting elastic interactions amongst such patterns. (author)

  9. Development of real-time motion capture system for 3D on-line games linked with virtual character (United States)

    Kim, Jong Hyeong; Ryu, Young Kee; Cho, Hyung Suck


    Motion tracking method is being issued as essential part of the entertainment, medical, sports, education and industry with the development of 3-D virtual reality. Virtual human character in the digital animation and game application has been controlled by interfacing devices; mouse, joysticks, midi-slider, and so on. Those devices could not enable virtual human character to move smoothly and naturally. Furthermore, high-end human motion capture systems in commercial market are expensive and complicated. In this paper, we proposed a practical and fast motion capturing system consisting of optic sensors, and linked the data with 3-D game character with real time. The prototype experiment setup is successfully applied to a boxing game which requires very fast movement of human character.

  10. Optimal Hedging and Pricing of Equity-Linked Life Insurance Contracts in a Discrete-Time Incomplete Market

    Directory of Open Access Journals (Sweden)

    Norman Josephy


    Full Text Available We present a method of optimal hedging and pricing of equity-linked life insurance products in an incomplete discrete-time financial market. A pure endowment life insurance contract with guarantee is used as an example. The financial market incompleteness is caused by the assumption that the underlying risky asset price ratios are distributed in a compact interval, generalizing the assumptions of multinomial incomplete market models. For a range of initial hedging capitals for the embedded financial option, we numerically solve an optimal hedging problem and determine a risk-return profile of each optimal non-self-financing hedging strategy. The fair price of the insurance contract is determined according to the insurer's risk-return preferences. Illustrative numerical results of testing our algorithm on hypothetical insurance contracts are documented. A discussion and a test of a hedging strategy recalibration technique for long-term contracts are presented.

  11. Timing of pollen release and stigma receptivity period of Piper vicosanum: New insights into sexual reproduction of the genus. (United States)

    Valentin-Silva, Adriano; Coelho, Victor Peçanha de Miranda; Ventrella, Marília Contin; Vieira, Milene Faria


    Dichogamy is a common characteristic among angiosperms, including Piper species. In this genus, the tiny flowers are morphologically similar and have an asynchronous stamen development. However, there is no information on the duration of stigma receptivity and whether it overlaps with pollen release. To better understand mechanisms of floral function in Piper vicosanum, we provide a detailed characterization of the timing of pollen release from the four stamens and the period of stigma receptivity and exposure mode of the receptive areas. We investigated plants of a natural population in a semideciduous seasonal forest (Viçosa, Minas Gerais State, southeastern Brazil), based on chemical tests, light microscopy, and scanning electron microscopy analyses. Incomplete protogyny-a mechanism that favors outcrossing-was recorded. The period of stigma receptivity was long (14 d), and the sequential exposure and senescence of stigmatic papillae occurred gradually and in a basipetal direction. Pollen release began 2-6 d after the beginning of the pistillate phase, with an average pollen viability of 87.7%, during the bisexual flower phase. Pollen was released for up to 6 d and occurred in one stamen at a time. The fruit set observed in tests of self-pollination indicated self-compatibility. The gradual and sequential exposure of stigmatic papillae in P. vicosanum flowers is described here as the mechanism for the long duration of receptivity. Anther development and pollen release were also sequential. These findings are yet unreported reproductive characteristics of the genus and offer new perspectives for future studies on the floral biology of other Piper species. © 2015 Botanical Society of America, Inc.

  12. STR analysis of human DNA from maggots fed on decomposing bodies: Assessment of the time period for successful analysis

    Directory of Open Access Journals (Sweden)

    Daniel Gachuiri Njau


    Full Text Available Frequently, forensic entomology is applied in the use of insect maggots for the identification of specimens or remains of humans. Maggot crop analysis could be valuable in criminal investigations when maggots are found at a crime scene and a corpse is absent. Human short tandem repeat (STR has previously been used to support the association of maggots to a specific corpse but not in the period at which the body has been decomposing. The aim of this research was to assess the time period for successful STR analyses of human DNA from third instar maggots (Protophormia terraenovae obtained from decomposing human corpses as well as to investigate the human DNA turnover and degradation in the maggot crop after they are removed from food and/or are fed on a beef (a new/different food source. Results showed that the amount of human DNA recovered from maggots decreased with time in all cases. For maggots fed on beef, the human DNA could only be recovered up to day two and up to day four for the starved maggots. STR analyses of human DNA from maggots’ crop content using 16 loci generated profiles that matched those of reference samples although some of the alleles were not amplifiable therefore generating partial profiles for the samples starved for 4 days and those fed on beef. This may be due to nuclease activity present in the gut of larvae that may have caused degradation of DNA and consequently reduction in DNA yield. It was possible to identify the decomposing body using STRs as markers.

  13. On quality control procedures for solar radiation and meteorological measures, from subhourly to montly average time periods (United States)

    Espinar, B.; Blanc, P.; Wald, L.; Hoyer-Klick, C.; Schroedter-Homscheidt, M.; Wanderer, T.


    Meteorological data measured by ground stations are often a key element in the development and validation of methods exploiting satellite images. These data are considered as a reference against which satellite-derived estimates are compared. Long-term radiation and meteorological measurements are available from a large number of measuring stations. However, close examination of the data often reveals a lack of quality, often for extended periods of time. This lack of quality has been the reason, in many cases, of the rejection of large amount of available data. The quality data must be checked before their use in order to guarantee the inputs for the methods used in modelling, monitoring, forecast, etc. To control their quality, data should be submitted to several conditions or tests. After this checking, data that are not flagged by any of the test is released as a plausible data. In this work, it has been performed a bibliographical research of quality control tests for the common meteorological variables (ambient temperature, relative humidity and wind speed) and for the usual solar radiometrical variables (horizontal global and diffuse components of the solar radiation and the beam normal component). The different tests have been grouped according to the variable and the average time period (sub-hourly, hourly, daily and monthly averages). The quality test may be classified as follows: • Range checks: test that verify values are within a specific range. There are two types of range checks, those based on extrema and those based on rare observations. • Step check: test aimed at detecting unrealistic jumps or stagnation in the time series. • Consistency checks: test that verify the relationship between two or more time series. The gathered quality tests are applicable for all latitudes as they have not been optimized regionally nor seasonably with the aim of being generic. They have been applied to ground measurements in several geographic locations, what

  14. Multimodal sensory integration during sequential eating--linking chewing activity, aroma release, and aroma perception over time. (United States)

    Leclercq, Ségolène; Blancher, Guillaume


    The respective effects of chewing activity, aroma release from a gelled candy, and aroma perception were investigated. Specifically, the study aimed at 1) comparing an imposed chewing and swallowing pattern (IP) and free protocol (FP) on panelists for in vivo measurements, 2) investigating carryover effects in sequential eating, and 3) studying the link between instrumental data and their perception counterpart. Chewing activity, in-nose aroma concentration, and aroma perception over time were measured by electromyography, proton transfer reaction-mass spectrometry, and time intensity, respectively. Model gel candies were flavored at 2 intensity levels (low-L and high-H). The panelists evaluated 3 sequences (H then H, H then L, and L then H) in duplicates with both IP and FP. They scored aroma intensity over time while their in-nose aroma concentrations and their chewing activity were measured. Overall, only limited advantages were found in imposing a chewing and swallowing pattern for instrumental and sensory data. In addition, the study highlighted the role of brain integration on perceived intensity and dynamics of perception, in the framework of sequential eating without rinsing. Because of the presence of adaptation phenomena, contrast effect, and potential taste and texture cross-modal interaction with aroma perception, it was concluded that dynamic in-nose concentration data provide only one part of the perception picture and therefore cannot be used alone in prediction models.

  15. Effects of U.S. Navy Diver Training on Physiological Parameters, Time of Useful Consciousness and Cognitive Performance During Periods of Normobaric Hypoxia (United States)


    TRAINING ON PHYSIOLOGICAL PARAMETERS, TIME OF USEFULL CONSCIOUSNESS, AND COGNITIVE PERFORMANCE DURING PERIODS OF NORMOBARIC HYPOXIA...Sato, Y. Watanabe, "Time of Usefull Consciousness Determination in Aircrew Members with Rerference to Prior Altitude Chamber Experience and Age

  16. Population density and phenology of Tetranychus urticae (Acari: Tetranychidae) in hop is linked to the timing of sulfur applications. (United States)

    Woods, J L; Dreves, A J; Fisher, G C; James, D G; Wright, L C; Gent, D H


    The twospotted spider mite, Tetranychus urticae Koch, is a worldwide pest of numerous agronomic and horticultural plants. Sulfur fungicides are known to induce outbreaks of this pest on several crops, although mechanisms associated with sulfur-induced mite outbreaks are largely unknown. Studies were conducted during 2007-2009 in Oregon and Washington hop yards to evaluate the effect of timing of sulfur applications on T. urticae and key predators. In both regions, applications of sulfur made relatively late in the growing season (mid-June to mid-July) were associated with the greatest exacerbation of spider mite outbreaks, particularly in the upper canopy of the crop. The severity of mite outbreaks was closely associated with sulfur applications made during a relatively narrow time period coincident with the early exponential phase of spider mite increase and rapid host growth. A nonlinear model relating mean cumulative mite days during the time of sulfur sprays to the percent increase in total cumulative mite days (standardized to a nontreated plot) explained 58% of the variability observed in increased spider mite severity related to sulfur spray timing. Spatial patterns of spider mites in the Oregon plots indicated similar dispersal of motile stages of spider mites among leaves treated with sulfur versus nontreated leaves; however, in two of three years, eggs were less aggregated on leaves of sulfur-treated plants, pointing to enhanced dispersal. Apart from one experiment in Washington, relatively few predatory mites were observed during the course of these studies, and sulfur-induced mite outbreaks generally occurred irrespective of predatory mite abundance. Collectively, these studies indicate sulfur induces mite outbreaks through direct or indirect effects on T. urticae, mostly independent of predatory mite abundance or toxicity to these predators. Avoidance of exacerbation of spider mite outbreaks by sulfur sprays was achieved by carefully timing

  17. Sociodemographic variations in the amount, duration and cost of potentially preventable hospitalisation for chronic conditions among Aboriginal and non-Aboriginal Australians: a period prevalence study of linked public hospital data


    Banham, David; Chen, Tenglong; Karnon, Jonathan; Brown, Alex; Lynch, John


    Objectives To determine disparities in rates, length of stay (LOS) and hospital costs of potentially preventable hospitalisations (PPH) for selected chronic conditions among Aboriginal and non-Aboriginal South Australians (SA), then examine associations with area-level socioeconomic disadvantage and remoteness. Setting Period prevalence study using linked, administrative public hospital records. Participants Participants included all SA residents in 2005–2006 to 2010–2011. Analysis focused on...

  18. Climate regime shifts in paleoclimate time series from the Yucatán Peninsula: from the Preclassic to Classic period (United States)

    Polanco Martínez, Josue M.; Medina-Elizalde, Martin; Burns, Stephen J.; Jiang, Xiuyang; Shen, Chuan-Chou


    It has been widely accepted by the paleoclimate and archaeology communities that extreme climate events (especially droughts) and past climate change played an important role in the cultural changes that occurred in at least some parts of the Maya Lowlands, from the Pre-Classic (2000 BC to 250 AD) to Post-Classic periods (1000 to 1521 AD) [1, 2]. In particular, a large number of studies suggest that the decline of the Maya civilization in the Terminal Classic Period was greatly influenced by prolonged severe drought events that probably triggered significant societal disruptions [1, 3, 4, 5]. Going further on these issues, the aim of this work is to detect climate regime shifts in several paleoclimate time series from the Yucatán Peninsula (México) that have been used as rainfall proxies [3, 5, 6, 7]. In order to extract information from the paleoclimate data studied, we have used a change point method [8] as implemented in the R package strucchange, as well as the RAMFIT method [9]. The preliminary results show for all the records analysed a prominent regime shift between 400 to 200 BCE (from a noticeable increase to a remarkable fall in precipitation), which is strongest in the recently obtained stalagmite (Itzamna) delta18-O precipitation record [7]. References [1] Gunn, J. D., Matheny, R. T., Folan, W. J., 2002. Climate-change studies in the Maya area. Ancient Mesoamerica, 13(01), 79-84. [2] Yaeger, J., Hodell, D. A., 2008. The collapse of Maya civilization: assessing the interaction of culture, climate, and environment. El Niño, Catastrophism, and Culture Change in Ancient America, 197-251. [3] Hodell, D. A., Curtis, J. H., Brenner, M., 1995. Possible role of climate in the collapse of Classic Maya civilization. Nature, 375(6530), 391-394. [4] Aimers, J., Hodell, D., 2011. Societal collapse: Drought and the Maya. Nature 479(7371), 44-45 (2011). [5] Medina-Elizalde, M., Rohling, E. J., 2012. Collapse of Classic Maya civilization related to modest reduction

  19. EOQ Model for Deteriorating Items with exponential time dependent Demand Rate under inflation when Supplier Credit Linked to Order Quantity

    Directory of Open Access Journals (Sweden)

    Rakesh Prakash Tripathi


    Full Text Available In paper (2004 Chang studied an inventory model under a situation in which the supplier provides the purchaser with a permissible delay of payments if the purchaser orders a large quantity. Tripathi (2011 also studied an inventory model with time dependent demand rate under which the supplier provides the purchaser with a permissible delay in payments. This paper is motivated by Chang (2004 and Tripathi (2011 paper extending their model for exponential time dependent demand rate. This study develops an inventory model under which the vendor provides the purchaser with a credit period; if the purchaser orders large quantity. In this chapter, demand rate is taken as exponential time dependent. Shortages are not allowed and effect of the inflation rate has been discussed. We establish an inventory model for deteriorating items if the order quantity is greater than or equal to a predetermined quantity. We then obtain optimal solution for finding optimal order quantity, optimal cycle time and optimal total relevant cost. Numerical examples are given for all different cases. Sensitivity of the variation of different parameters on the optimal solution is also discussed. Mathematica 7 software is used for finding numerical examples.

  20. Rock bream iridovirus (RBIV) replication in rock bream (Oplegnathus fasciatus) exposed for different time periods to susceptible water temperatures. (United States)

    Jung, Myung-Hwa; Nikapitiya, Chamilani; Vinay, Tharabenahalli-Nagaraju; Lee, Jehee; Jung, Sung-Ju


    Rock bream iridovirus (RBIV) is a member of the Megalocytivirus genus that causes severe mortality to rock bream. Water temperature is known to affect the immune system and susceptibility of fish to RBIV infection. In this study, we evaluated the time dependent virus replication pattern and time required to completely eliminate virus from the rock bream body against RBIV infection at different water temperature conditions. The rock bream was exposed to the virus and held at 7 (group A1), 4 (group A2) and 2 days (group A3) at 23 °C before the water temperature was reduced to 17 °C. A total of 28% mortality was observed 24-35 days post infection (dpi) in only the 7 day exposure group at 23 °C. In all 23 °C exposure groups, virus replication peaked at 20 to 22 dpi (10 6 -10 7 /μl). In recovery stages (30-100 dpi), the virus copy number was gradually reduced, from 10 6 to 10 1 with faster decreases in the shorter exposure period group at 23 °C. When the water temperature was increased in surviving fish from 17 to 26 °C at 70 dpi, they did not show any mortality or signs of disease and had low virus copy numbers (below 10 2 /μl). Thus, fish need at least 50 days from peaked RBIV levels (approximately 20-25 dpi) to inhibit the virus. This indicates that maintaining the fish at low water temperature (17 °C) for 70 days is sufficient to eradicate RBIV from fish body. Thus, RBIV could be eliminated slowly from the fish body and the virus may be completely eliminated under the threshold of causing mortality. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Detection of motion artifact patterns in photoplethysmographic signals based on time and period domain analysis

    International Nuclear Information System (INIS)

    Couceiro, R; Carvalho, P; Paiva, R P; Henriques, J; Muehlsteff, J


    The presence of motion artifacts in photoplethysmographic (PPG) signals is one of the major obstacles in the extraction of reliable cardiovascular parameters in continuous monitoring applications. In the current paper we present an algorithm for motion artifact detection based on the analysis of the variations in the time and the period domain characteristics of the PPG signal. The extracted features are ranked using a normalized mutual information feature selection algorithm and the best features are used in a support vector machine classification model to distinguish between clean and corrupted sections of the PPG signal. The proposed method has been tested in healthy and cardiovascular diseased volunteers, considering 11 different motion artifact sources. The results achieved by the current algorithm (sensitivity—SE: 84.3%, specificity—SP: 91.5% and accuracy—ACC: 88.5%) show that the current methodology is able to identify both corrupted and clean PPG sections with high accuracy in both healthy (ACC: 87.5%) and cardiovascular diseases (ACC: 89.5%) context. (paper)

  2. Psychological Distress in Healthy Low-Risk First-Time Mothers during the Postpartum Period: An Exploratory Study

    Directory of Open Access Journals (Sweden)

    Christina Murphey


    Full Text Available Psychological distress, defined as depression, anxiety, and insomnia in this study, can occur following the birth of a baby as new mothers, in addition to marked physiological changes, are faced with adapting to new roles and responsibilities. We investigated the cooccurrence of stress, depression, anxiety, and insomnia in mothers during the postpartum period; tested the feasibility of study methods and procedures for use in this population; and identified new mothers interest in using cranial electrotherapy stimulation (CES as an intervention for reducing psychological distress. We recruited healthy, low-risk, English speaking first-time mothers, ages 18–32 years, with healthy babies (N=33, within 12 months of an uncomplicated birth. Participants completed the PSS, HAM-D14, HAM-A17, and PSQI19. No problems were encountered with study procedures. Mothers reported a high interest (4.9 in the potential use of CES to treat or prevent the occurrence of psychological distress. All participants (N=33 reported moderate levels of depression and anxiety, while 75.8% (n=25 reported insomnia. PSS scores were within the norms for healthy women. Further research is recommended to investigate if our findings can be replicated or if different patterns of associations emerge. Implications for clinical practice are addressed.

  3. Leisure-time physical activity and breast cancer risk by hormone receptor status: effective life periods and exercise intensity. (United States)

    Suzuki, Reiko; Iwasaki, Motoki; Kasuga, Yoshio; Yokoyama, Shiro; Onuma, Hiroshi; Nishimura, Hideki; Kusama, Ritsu; Shimazu, Taichi; Tsugane, Shoichiro


    Physical activity may decrease breast cancer risk. However, it is unclear what intensity of exercise and during which life periods this effect on decreasing risk is efficiently expressed, and whether the associations differ by the estrogen-/progesterone- receptor (ER/PR) status of tumors. We investigated associations between age- and intensity-specific leisure-time physical activity and ER/PR-defined breast cancer risk. We conducted a hospital-based case-control study in Nagano, Japan. Subjects were 405 cases newly diagnosed (>99% known ER/PR) from 2001 to 2005, who were age-/area-matched with 405 controls. Activity was assessed with a self-reported questionnaire which considered intensity level (moderate and/or strenuous) at different ages (at 12 and 20 years, and in the previous 5 years). Odds ratios (ORs) and 95% confidence intervals were calculated using logistic regression. Strenuous but not moderate physical activity at age 12 was inversely associated with pre- and postmenopausal breast cancer risk across ER/PR subtypes [overall OR(≥ 5 days/week vs. none) = 0.24 (0.14-0.43)]. Moderate physical activity in the previous 5 years was significantly associated with a decrease in risk for postmenopausal ER + PR + tumors only [OR(≥ 1 day/week vs. none) = 0.35 (0.18-0.67)]. Strenuous activity in teens and moderate activity after menopause may contribute to a reduction in breast cancer risk.

  4. Time skewing and amplitude nonlinearity mitigation by feedback equalization for 56 Gbps VCSEL-based PAM-4 links (United States)

    You, Yue; Zhang, Wenjia; Sun, Lin; Du, Jiangbing; Liang, Chenyu; Yang, Fan; He, Zuyuan


    The vertical cavity surface emitting laser (VCSEL)-based multimode optical transceivers enabled by pulse amplitude modulation (PAM)-4 will be commercialized in near future to meet the 400-Gbps standard short reach optical interconnects. It is still challenging to achieve over 56/112-Gbps with the multilevel signaling as the multimode property of the device and link would introduce the nonlinear temporal response for the different levels. In this work, we scrutinize the distortions that relates to the multilevel feature of PAM-4 modulation, and propose an effective feedback equalization scheme for 56-Gbps VCSEL-based PAM-4 optical interconnects system to mitigate the distortions caused by eye timing-skew and nonlinear power-dependent noise. Level redistribution at Tx side is theoretically modeled and constructed to achieve equivalent symbol error ratios (SERs) of four levels and improved BER performance. The cause of the eye skewing and the mitigation approach are also simulated at 100-Gbps and experimentally investigated at 56-Gbps. The results indicate more than 2-dB power penalty improvement has been achieved by using such a distortion aware equalizer.

  5. Ruin probabilities with compounding assets for discrete time finite horizon problem, independent period claim sizes and general premium structure

    NARCIS (Netherlands)

    Kok, de A.G.


    In this paper, we present fast and accurate approximations for the probability of ruin over a finite number of periods, assuming inhomogeneous independent claim size distributions and arbitrary premium income in subsequent periods. We develop exact recursive expressions for the non-ruin

  6. Ruin probabilities with compounding assets for discrete time finite horizon problems, independent period claim sizes and general premium structure

    NARCIS (Netherlands)

    Kok, de A.G.


    In this paper we present fast and accurate approximations for the probability of ruin over a finite number of periods, assuming inhomogeneous independent claim size distributions and arbitrary premium income in subsequent periods. We develop exact recursive expressions for the non-ruin probabilities

  7. Summary of Time Period-Based and Other Approximation Methods for Determining the Capacity Value of Wind and Solar in the United States: September 2010 - February 2012

    Energy Technology Data Exchange (ETDEWEB)

    Rogers, J.; Porter, K.


    This paper updates previous work that describes time period-based and other approximation methods for estimating the capacity value of wind power and extends it to include solar power. The paper summarizes various methods presented in utility integrated resource plans, regional transmission organization methodologies, regional stakeholder initiatives, regulatory proceedings, and academic and industry studies. Time period-based approximation methods typically measure the contribution of a wind or solar plant at the time of system peak - sometimes over a period of months or the average of multiple years.

  8. The existence and regularity of time-periodic solutions to the three-dimensional Navier–Stokes equations in the whole space

    International Nuclear Information System (INIS)

    Kyed, Mads


    The existence, uniqueness and regularity of time-periodic solutions to the Navier–Stokes equations in the three-dimensional whole space are investigated. We consider the Navier–Stokes equations with a non-zero drift term corresponding to the physical model of a fluid flow around a body that moves with a non-zero constant velocity. The existence of a strong time-periodic solution is shown for small time-periodic data. It is further shown that this solution is unique in a large class of weak solutions that can be considered physically reasonable. Finally, we establish regularity properties for any strong solution regardless of its size. (paper)

  9. Early life disease programming during the preconception and prenatal period: making the link between stressful life events and type-1 diabetes.

    Directory of Open Access Journals (Sweden)

    Jasveer Virk

    Full Text Available BACKGROUND: To assess the risk of developing Type-1 diabetes among children who were exposed to maternal bereavement during the prenatal or 1-year preconception period. METHODS: We identified N = 1,548,746 singleton births born in Denmark between January 1(st 1979 through December 31(st 2004, and their next of kin. Altogether, 39,857 children were exposed to bereavement during their prenatal life. The main outcome of interest was hospitalization for type-1 diabetes (ICD 8: 249; ICD 10: E10. RESULTS: We found the strongest association for type-1 diabetes among children exposed to traumatic father or sibling deaths (aIRR: 2.03, 1.22-3.38; the association was mainly seen for girls (aIRR: 2.91, 1.61-5.26. CONCLUSIONS: We found evidence to suggest that female fetuses exposed to severe prenatal stress are at increased risk for developing type-1 diabetes.

  10. Women in post-trafficking services in moldova: diagnostic interviews over two time periods to assess returning women's mental health

    Directory of Open Access Journals (Sweden)

    Gorceag Lilia T


    Full Text Available Abstract Background Trafficking in women is a widespread human rights violation commonly associated with poor mental health. Yet, to date, no studies have used psychiatric diagnostic assessment to identify common forms of mental distress among survivors returning to their home country. Methods A longitudinal study was conducted of women aged 18 and over who returned to Moldova between December 2007 and December 2008 registered by the International Organisation for Migration as a survivor of human trafficking. Psychiatric diagnoses in women at a mean of 6 months after return (range 2-12 months were made by a trained Moldavian psychiatrist using the Structured Clinical Interview for DSM-IV, and compared with diagnoses recorded in the same women within 5 days of return. We described the socio-demographic characteristics of the women in the sample including both pre and post-trafficking information. We then described the distribution of mental health diagnoses recorded during the crisis intervention phase (1-5 days after return and the re-integration phase (2-12 months after return. We compared diagnoses at the patient level between the two time points by tabulating the diagnoses and carrying out a kappa test of agreement and the Stuart-Maxwell test for marginal homogeneity (an extension of the McNemar test to kxk table. Results 120/176 (68% eligible women participated. At 2-12 months after their return, 54% met criteria for at least one psychiatric diagnoses comprising post-traumatic stress disorder (PTSD alone (16%; co-morbid PTSD (20%; other anxiety or mood disorder (18%. 85% of women who had been diagnosed in the crisis phase with co-morbid PTSD or with another anxiety or mood disorder sustained a diagnosis of any psychiatric disorder when followed up during rehabilitation. Conclusions Trafficked women returning to their country of origin are likely to suffer serious psychological distress that may endure well beyond the time they return. Women

  11. Analysis of a time-delayed mathematical model for tumour growth with an almost periodic supply of external nutrients. (United States)

    Xu, Shihe; Bai, Meng; Zhang, Fangwei


    In this paper, the existence, uniqueness and exponential stability of almost periodic solutions for a mathematical model of tumour growth are studied. The establishment of the model is based on the reaction-diffusion dynamics and mass conservation law and is considered with a delay in the cell proliferation process. Using a fixed-point theorem in cones, the existence and uniqueness of almost periodic solutions for different parameter values of the model is proved. Moreover, by the Gronwall inequality, sufficient conditions are established for the exponential stability of the unique almost periodic solution. Results are illustrated by computer simulations.

  12. Permanence for a class of periodic time-dependent predator-prey system with dispersal in a patchy-environment

    International Nuclear Information System (INIS)

    Zhang Long; Teng Zhidong


    In this paper, we study two species predator-prey Lotka-Volterra type dispersal system with periodic coefficients in two patches, in which both the prey and predator species can disperse between two patches. By utilizing analytic method, sufficient and realistic conditions on permanence and the existence of periodic solution are established. The theoretical results are confirmed by a special example and numerical simulations

  13. 12 CFR 218.781 - Exemption from the definition of “broker” for banks for a limited period of time. (United States)


    ...” for banks for a limited period of time. A bank is exempt from the definition of the term “broker... 12 Banks and Banking 2 2010-01-01 2010-01-01 false Exemption from the definition of âbrokerâ for banks for a limited period of time. 218.781 Section 218.781 Banks and Banking FEDERAL RESERVE SYSTEM...

  14. 17 CFR 247.781 - Exemption from the definition of “broker” for banks for a limited period of time. (United States)


    ... “broker” for banks for a limited period of time. A bank is exempt from the definition of the term “broker... 17 Commodity and Securities Exchanges 3 2010-04-01 2010-04-01 false Exemption from the definition of âbrokerâ for banks for a limited period of time. 247.781 Section 247.781 Commodity and Securities...

  15. Recent Structural Change in Remote Sensing Data Time Series Linked to Farm Management in Horn of Africa (1999-2009) (United States)

    Crisci, A.; Vignaroli, P.; Genesio, L.; Grasso, V.; Bacci, M.; Tarchiani, V.; Capecchi, V.


    Food security in East Africa region essentially depends on the stability of rain-fed crops farming, which renders its society vulnerable to climatic fluctuations. These ones in Africa are most widely and directly related to rainfall. In this study, the relation between recent spatial rainfall variability and vegetation dynamics has been investigated for East Africa territories. Satellite raster products SPOT-4 Vegetation 1 km resolution (Saint, 1995) and RFE (rainfall estimates) from Famine Early Warning Systems Network (FEWS NET) are used. The survey is carried out at administrative level scale using 10-day summaries extracted from raster data for each spatial area unit thanks to specific polygonal layers. Time series covers two different periods: 1996-2009 for rainfall estimates and 1999-2009 for NDVI. The first step of the analysis has been to build for each administrative unit a coherent set of data, along the time series, suitable to be processed with state-of-art statistical tools. The analysis is based on the assumption that every structural break in vegetation dynamics could be caused by two alternative/complementary causes, namely: (i) modifications in crop farming systems (adaptation strategy) related to eventual break-shift in rainfall regime and/or (ii) other socio-economic factors. BFAST (Verbesselt et al, 2010) R package are employed to lead a comprehensive breakpoint analysis on 10-day RFE (spatial mean and standard deviation) and 10-day NDVI ones (spatial mean, mode and standard deviation). The cross-viewing of the years where significant breaks have occurred, throughout opportune GIS layering, provides an explorative interpretation of spatial climate/vegetation dynamics in the whole area. Moreover, the spatial and temporal pattern of ecosystem dynamics in response to climatic variability has been investigated using wavelet coherency by SOWAS R package (Maraun, 2007). The wavelet coherency (WCOH) is a normalized time and scale resolved measure for

  16. Depression and suicidality during the postpartum period after first time deliveries, active component service women and dependent spouses, U.S. Armed Forces, 2007-2012. (United States)

    Do, Tai; Hu, Zheng; Otto, Jean; Rohrbeck, Patricia


    Although suicide is a leading cause of death among new mothers during the postpartum period, there has been limited research on self-harm in the postpartum period and associated risk factors. One potential risk factor for suicidality (completed suicides, suicide attempts, and suicide ideation including thoughts of self harm) during the postpartum period is postpartum depression (PPD). In this study of women who gave birth for the first time between 1 January 2007 and 31 December 2011, 5,267 (9.9% of all who delivered) active component service women and 10,301 (8.2%) dependent spouses received incident PPD diagnoses during the one year postpartum period; 213 (0.4%) service women and 221 (0.2%) dependent spouses were diagnosed with incident suicidality. After adjusting for the effects of other covariates, service women with PPD had 42.2 times the odds to be diagnosed with suicidality in the postpartum period compared to service women without PPD; dependent spouses with PPD had 14.5 times the odds compared to those without PPD. The findings of this report suggest that a history of mental disorders was common among service women and dependent spouses with PPD in the postpartum period, and, in turn, PPD was a strong predictor for suicidality in the postpartum period. These results emphasize the importance of PPD screening during the postpartum period. They also suggest that additional focused screening for suicidal behavior among those already diagnosed with PPD may be warranted.

  17. [Effects of deep plowing time during the fallow period on water storage-consumption characteristics and wheat yield in dry-land soil. (United States)

    Dang, Jian You; Pei, Xue Xia; Zhang, Ding Yi; Wang, Jiao Ai; Zhang, Jing; Wu, Xue Ping


    Through a three-year field trail, effects of deep plowing time during the fallow period on water storage of 0-200 cm soil before sowing, water consumption of growth period, and growth and development of wheat were investigated. Results demonstrated that soil water storage (SWS) of the fallow period was influenced by deep plowing time, precipitation, and rainfall distribution. With postponing the time of deep plowing in the fallow period, SWS was increased firstly, and then decreased. SWS with deep plowing in early or middle of August was 23.9-45.8 mm more than that with deep plowing in mid-July. It would benefit SWS when more precipitation occurred in the fallow period or more rainfall was distributed in August and September. Deep plowing at a proper time could facilitate SWS, N and P absorption of wheat, and the number of stems before winter and the spike number. The yield of wheat with deep plowing in early or middle August was 3.67%-18.2% higher than that with deep plowing in mid-July, and it was positively correlated with water storage of 0-200 cm soil during the fallow period and SWS of each soil layer during the wheat growth period. However, this correlation coefficient would be weakened by adequate rainfall in spring, the critical growing period for wheat. The time of deep plowing mainly affected the water consumption at soil layer of 60-140 cm during wheat growth. Under current farming conditions of south Shanxi, the increased grain yield of wheat could be achieved by combining the measures of high wheat stubble and wheat straw covering for holding soil water and deep plowing between the Beginning of Autumn (August 6th) and the Limit of Heat (August 21st) for promoting soil water penetration characteristics to improve the number of stems before winter and spike.


    International Nuclear Information System (INIS)

    Levine, Alan M.; Bradt, Hale V.; Chakrabarty, Deepto; Corbet, Robin H. D.; Harris, Robert J.


    We present the results of a systematic search in ∼14 years of Rossi X-ray Timing Explorer All-Sky Monitor (ASM) data for evidence of periodicities. Two variations of the commonly used Fourier analysis search method have been employed to significantly improve upon the sensitivity achieved by Wen et al. in 2006, who also searched for periodicities in ASM data. In addition, the present search is comprehensive in terms of sources studied and frequency range covered, and has yielded the detection of the signatures of the orbital periods of eight low-mass X-ray binary systems and of ten high-mass X-ray binaries not listed in the tables of Wen et al. Orbital periods, epochs, signal amplitudes, modulation fractions, and folded light curves are given for each of these systems. Seven of the orbital periods are the most precise reported to date. In the course of this work, the 18.545 day orbital period of IGR J18483-0311 was co-discovered, and the first detections in X-rays were made of the ∼3.9 day orbital period of LMC X-1 and the ∼3.79 hr orbital period of 4U 1636-536. The results inform future searches for orbital and other periodicities in X-ray binaries.

  19. Sociodemographic variations in the amount, duration and cost of potentially preventable hospitalisation for chronic conditions among Aboriginal and non-Aboriginal Australians: a period prevalence study of linked public hospital data. (United States)

    Banham, David; Chen, Tenglong; Karnon, Jonathan; Brown, Alex; Lynch, John


    To determine disparities in rates, length of stay (LOS) and hospital costs of potentially preventable hospitalisations (PPH) for selected chronic conditions among Aboriginal and non-Aboriginal South Australians (SA), then examine associations with area-level socioeconomic disadvantage and remoteness. Period prevalence study using linked, administrative public hospital records. Participants included all SA residents in 2005-2006 to 2010-2011. Analysis focused on those individuals experiencing chronic PPH as defined by the Australian Institute of Health and Welfare. Number and rates (unadjusted, then adjusted for sex and age) of chronic PPH, total LOS and direct hospital costs by Aboriginality. Aboriginal SAs experienced higher risk of index chronic PPH compared with non-Aboriginals (11.5 and 6.2 per 1000 persons per year, respectively) and at younger ages (median age 48 vs 70 years). Once hospitalised, Aboriginal people experienced more chronic PPH events, longer total LOS with higher costs than non-Aboriginal people (2.6 vs 1.9 PPH per person; 11.7 vs 9.0 days LOS; at $A17 928 vs $A11 515, respectively). Compared with population average LOS, the standardised rate ratio of LOS among Aboriginal people increased by 0.03 (95% CI 0.00 to 0.07) as disadvantage rank increased and 1.04 (95% CI 0.63 to 1.44) as remoteness increased. Non-Aboriginal LOS also increased as disadvantage increased but at a lower rate (0.01 (95% CI 0.01 to 0.01)). Costs of Aboriginal chronic PPH increased by 0.02 (95% CI 0.00 to 0.06) for each increase in disadvantage and 1.18 (95% CI 0.80 to 1.55) for increased remoteness. Non-Aboriginal costs also increased as disadvantage increased but at lower rates (0.01 (95% CI 0.01 to 0.01)). Aboriginal people's heightened risk of chronic PPH resulted in more time in hospital and greater cost. Systematic disparities in chronic PPH by Aboriginality, area disadvantage and remoteness highlight the need for improved uptake of effective primary care. Routine

  20. Time variation of meteorological elements as controlled by the quasi-biennial periodicity in the solar phenomena

    International Nuclear Information System (INIS)

    Inoue, Michiharu; Sakurai, Kunitomo


    It is shown that the quasi-biennial oscillation observed on some meteorological elements as the ozone content at middle latitudes, both north and south, the zonal wind velocity at the equator and the ground-level temperature at middle latitudes, is produced by the variation of the ultraviolet flux emitted from the sun, which is varying with the solar activity with the period of about 26 months. The ozone content is varying in phase with the ultraviolet flux and the solar activity, whereas the other two elements mentioned above are changing out of phase with these phenomena. There is a possibility that both these meteorological elements and the solar activity are varying quasi-biennially while being modulated by the 26 month periodicity in the efficiency of thermonuclear fusions at the central core of the sun. (author)

  1. Real-Time Magnitude Characterization of Large Earthquakes Using the Predominant Period Derived From 1 Hz GPS Data (United States)

    Psimoulis, Panos A.; Houlié, Nicolas; Behr, Yannik


    Earthquake early warning (EEW) systems' performance is driven by the trade-off between the need for a rapid alert and the accuracy of each solution. A challenge for many EEW systems has been the magnitude saturation for large events (MW > 7) and the resulting underestimation of seismic moment magnitude. In this study, we test the performance of high-rate (1 Hz) GPS, based on seven seismic events, to evaluate whether long-period ground motions can be measured well enough to infer reliably earthquake predominant periods. We show that high-rate GPS data allow the computation of a GPS-based predominant period (τg) to estimate lower bounds for the magnitude of earthquakes and distinguish between large (MW > 7) and great (MW > 8) events and thus extend the capability of EEW systems for larger events. It has also identified the impact of the different values of the smoothing factor α on the τg results and how the sampling rate and the computation process differentiate τg from the commonly used τp.

  2. Non-existence of time-periodic solutions of the Dirac equation in a Reissner-Nordström black hole background (United States)

    Finster, Felix; Smoller, Joel; Yau, Shing-Tung


    It is shown analytically that the Dirac equation has no normalizable, time-periodic solutions in a Reissner-Nordström black hole background; in particular, there are no static solutions of the Dirac equation in such a background metric. The physical interpretation is that Dirac particles can either disappear into the black hole or escape to infinity, but they cannot stay on a periodic orbit around the black hole.

  3. The effect of temperature and extraction period of time on the chemicals content of emprit ginger ethanol extract (Zingiber officinale var. Rubrum) (United States)

    Ratnaningrum, Diah; Endah, Een Sri; Pudjiraharti, Sri


    Research on extraction method of emprit ginger using ethanol with agitation of 100 rpm at different temperatures (ambient temperature, 40, and 50°C) and various extraction period of times (30, 60, and 90 minutes) was conducted. Analysis of chemicals content i.e. total phenolic and total flavonoid. The objective of this work was to study the effect of temperatures and extraction period of times on the chemicals content of its ethanol extract. Based on the results of the test, the highest content total flavonoid (5.17% w/w) was resulted at 40°C for 90 minutes, while the total phenolic content was not affected by either temperature or extraction period of times used. The content of total phenolic was around 2.39% to 2.65% w/w.

  4. A statistical forecast model using the time-scale decomposition technique to predict rainfall during flood period over the middle and lower reaches of the Yangtze River Valley (United States)

    Hu, Yijia; Zhong, Zhong; Zhu, Yimin; Ha, Yao


    In this paper, a statistical forecast model using the time-scale decomposition method is established to do the seasonal prediction of the rainfall during flood period (FPR) over the middle and lower reaches of the Yangtze River Valley (MLYRV). This method decomposites the rainfall over the MLYRV into three time-scale components, namely, the interannual component with the period less than 8 years, the interdecadal component with the period from 8 to 30 years, and the interdecadal component with the period larger than 30 years. Then, the predictors are selected for the three time-scale components of FPR through the correlation analysis. At last, a statistical forecast model is established using the multiple linear regression technique to predict the three time-scale components of the FPR, respectively. The results show that this forecast model can capture the interannual and interdecadal variation of FPR. The hindcast of FPR during 14 years from 2001 to 2014 shows that the FPR can be predicted successfully in 11 out of the 14 years. This forecast model performs better than the model using traditional scheme without time-scale decomposition. Therefore, the statistical forecast model using the time-scale decomposition technique has good skills and application value in the operational prediction of FPR over the MLYRV.

  5. 41 CFR 302-2.10 - Does the 2-year time period in § 302-2.8 include time that I cannot travel and/or transport my... (United States)


    ... 41 Public Contracts and Property Management 4 2010-07-01 2010-07-01 false Does the 2-year time period in § 302-2.8 include time that I cannot travel and/or transport my household effects due to... time that I cannot travel and/or transport my household effects due to shipping restrictions to or from...

  6. Drainage estimation to aquifer and water use irrigation efficiency in semi-arid zone for a long period of time (United States)

    Jiménez-Martínez, J.; Molinero-Huguet, J.; Candela, L.


    Water requirements for different crop types according to soil type and climate conditions play not only an important role in agricultural efficiency production, though also for water resources management and control of pollutants in drainage water. The key issue to attain these objectives is the irrigation efficiency. Application of computer codes for irrigation simulation constitutes a fast and inexpensive approach to study optimal agricultural management practices. To simulate daily water balance in the soil, vadose zone and aquifer the VisualBALAN V. 2.0 code was applied to an experimental area under irrigation characterized by its aridity. The test was carried out in three experimental plots for annual row crops (lettuce and melon), perennial vegetables (artichoke), and fruit trees (citrus) under common agricultural practices in open air for October 1999-September 2008. Drip irrigation was applied to crops production due to the scarcity of water resources and the need for water conservation. Water level change was monitored in the top unconfined aquifer for each experimental plot. Results of water balance modelling show a good agreement between observed and estimated water level values. For the study period, mean drainage obtained values were 343 mm, 261 mm and 205 mm for lettuce and melon, artichoke and citrus respectively. Assessment of water use efficiency was based on the IE indicator proposed by the ASCE Task Committee. For the modelled period, water use efficiency was estimated as 73, 71 and 78 % of the applied dose (irrigation + precipitation) for lettuce and melon, artichoke and citrus, respectively.

  7. Cross-Sectional Distribution of GARCH Coefficients across S&P 500 Constituents: Time-Variation over the Period 2000-2012


    David Ardia; Lennart F. Hoogerheide


    We investigate the time-variation of the cross-sectional distribution of asymmetric GARCH model parameters over the S&P 500 constituents for the period 2000-2012. We find the following results. First, the unconditional variances in the GARCH model obviously show major time-variation, with a high level after the dot-com bubble and the highest peak in the latest financial crisis. Second, in these more volatile periods it is especially the persistence of deviations of volatility from is uncondit...

  8. Test bed for real-time image acquisition and processing systems based on FlexRIO, CameraLink, and EPICS

    International Nuclear Information System (INIS)

    Barrera, E.; Ruiz, M.; Sanz, D.; Vega, J.; Castro, R.; Juárez, E.; Salvador, R.


    Highlights: • The test bed allows for the validation of real-time image processing techniques. • Offers FPGA (FlexRIO) image processing that does not require CPU intervention. • Is fully compatible with the architecture of the ITER Fast Controllers. • Provides flexibility and easy integration in distributed experiments based on EPICS. - Abstract: Image diagnostics are becoming standard ones in nuclear fusion. At present, images are typically analyzed off-line. However, real-time processing is occasionally required (for instance, hot-spot detection or pattern recognition tasks), which will be the objective for the next generation of fusion devices. In this paper, a test bed for image generation, acquisition, and real-time processing is presented. The proposed solution is built using a Camera Link simulator, a Camera Link frame-grabber, a PXIe chassis, and offers software interface with EPICS. The Camera Link simulator (PCIe card PCIe8 DVa C-Link from Engineering Design Team) generates simulated image data (for example, from video-movies stored in fusion databases) using a Camera Link interface to mimic the frame sequences produced with diagnostic cameras. The Camera Link frame-grabber (FlexRIO Solution from National Instruments) includes a field programmable gate array (FPGA) for image acquisition using a Camera Link interface; the FPGA allows for the codification of ad-hoc image processing algorithms using LabVIEW/FPGA software. The frame grabber is integrated in a PXIe chassis with system architecture similar to that of the ITER Fast Controllers, and the frame grabber provides a software interface with EPICS to program all of its functionalities, capture the images, and perform the required image processing. The use of these four elements allows for the implementation of a test bed system that permits the development and validation of real-time image processing techniques in an architecture that is fully compatible with that of the ITER Fast Controllers

  9. PET imaging with copper-64 as a tool for real-time in vivo investigations of the necessity for cross-linking of polymeric micelles in nanomedicine. (United States)

    Jensen, Andreas I; Binderup, Tina; Ek, Pramod Kumar; Grandjean, Constance E; Rasmussen, Palle H; Kjaer, Andreas; Andresen, Thomas L


    Polymeric micelles in nanomedicine are often cross-linked to prevent disintegration in vivo. This typically requires clinically problematic chemicals or laborious procedures. In addition, cross-linking may interfere with advanced release strategies. Despite this, it is often not investigated whether cross-linking is necessary for efficient drug delivery. We used positron emission tomography (PET) imaging with 64 Cu to demonstrate general methodology for real-time in vivo investigations of micelle stability. Triblock copolymers with 4-methylcoumarin cores of ABC-type (PEG-PHEMA-PCMA) were functionalized in the handle region (PHEMA) with CB-TE2A chelators. Polymeric micelles were formed by dialysis and one half was core cross-linked (CL) by UV light and the other half was not (nonCL). Both CL and nonCL were radiolabeled with 64 Cu and compared in vivo in tumor-bearing mice, with free 64 Cu as control. Accumulation in relevant organs was quantified by region of interest analysis on PET images and ex vivo counting. It was observed that CL and nonCL showed limited differences in biodistribution from each other, whereas both differed markedly from control (free 64 Cu). This demonstrated that 4-methylcoumarin core micelles may form micelles that are stable in circulation even without cross-linking. The methodology presented here where individual unimers are radiolabeled is applicable to a wide range of polymeric micelle types. Copyright © 2017 John Wiley & Sons, Ltd.

  10. Period3 VNTR polymorphism influences the time-of-day pain onset of acute myocardial infarction with ST elevation. (United States)

    Lipkova, Jolana; Splichal, Zbynek; Bienertova-Vasku, Julie Anna; Jurajda, Michal; Parenica, Jiri; Vasku, Anna; Goldbergova, Monika Pavkova


    It is well established that the incidence and infarct size in acute myocardial infarction (AMI) is subject to circadian variations. At the molecular level, circadian clocks in distinct cells, including cardiomyocytes, generate 24-h cycles of biochemical processes. Possible imbalance or impairment in the cell clock mechanism may alter the cardiac metabolism and function and increase the susceptibility of cardiovascular diseases. One of the key components of the human clock system PERIOD3 (PER3) has been recently demonstrated to affect circadian expression of various genes in different tissues, including the heart. The variable number tandem repeat (VNTR) polymorphism (rs57875989) in gene Period3 (Per3) is related to multiple phenotypic parameters, including diurnal preference, sleep homeostasis, infection and cancer. The aim of our study was to investigate the effect of this polymorphism in AMI with ST elevation (STEMI). The study subjects (314 patients of Caucasian origin with STEMI, and 332 healthy controls) were genotyped for Per3 VNTR polymorphism using an allele-specific polymerase chain reaction. A gender difference in circadian rhythmicity of pain onset was observed with significant circadian pattern in men. Furthermore, the Per3(5/5) variant carriers were associated with higher levels of interleukin-6, B-type natriuretic peptide and lower vitamin A levels. By using cosinor analysis we observed different circadian distribution patterns of AMI onset at the level of genotype and allelic frequencies. Genotypes with at least one 4-repeat allele (Per3(4/5) and Per3(4/4)) (N = 264) showed remarkable circadian activity in comparison with Per3(5/5) (N = 50), especially in men. No significant differences in genotype and/or allele frequencies of Per3 VNTR polymorphism were observed when comparing STEMI cases and controls. Our results indicate that the Per3 VNTR may contribute to modulation of cardiac functions and interindividual differences in development and

  11. Multidisciplinary Approach to Determine the Optimal Time and Period for Extracting the Essential Oil from Mentha suaveolens Ehrh

    Directory of Open Access Journals (Sweden)

    Stefania Garzoli


    Full Text Available A comprehensive study on essential oils (EOs extracted from some Mentha suaveolens L. samples, collected in the countryside of Tarquinia, is reported. In this study, the procedure for essential oil preparation, in terms of harvesting and extraction time, was analyzed in detail for the first time. The GC/MS analysis, carried out on 18 samples, revealed that piperitenone oxide (PO, the main essential oils’ chemical constituent, is primarily responsible for the related antifungal activity. Nevertheless, EOs with lower PO content indicate that other chemicals, such as para-cymenene, may participate in exerting the EOs’ antifungal effect. Furthermore, the bacterial reverse mutation assay highlighted lack of mutagenic effect in all tested samples. Analysis of the results indicated that for higher activity, the essential oils should be produced with 3 h maximum hydrodistillation, regardless of the harvesting time. Differently, the maximum essential oil yield can be obtained in August and the highest piperitenone oxide percentage is obtainable in July.

  12. Factors associated to the length of time on mechanical ventilation in the postoperative period of cardiac surgery

    Directory of Open Access Journals (Sweden)

    Laura Fonseca

    Full Text Available Our objective was to identify factors associated with the duration of mechanical ventilation (MV postoperative to cardiac surgery and assess the association between duration of endotracheal intubation, length of stay in the Intensive Care Unit (ICU and hospital. Longitudinal, retrospective study of medical records of 116 adults undergoing cardiac surgery from March 2012 to May 2013. The mean age was 57±14 years, predominantly male and coronary artery bypass grafting surgery (52.6%. The MV time was 15.25(7.66 to 23.68 hours. Associated with longer MV was the age (r=0.5,p<0.001, comorbidities (r=0.344,p<0.001, cardiopulmonary bypass time (r=0.244,p=0.008, duration of continuous sedation (r=0.607,p<0.001, sedative doses (r=0.4, p<0.001, time of vasoconstrictors and vasodilators (r=0.711, p< 0.001, r=0.368, p<0.001, drainage of the 1st time (r=0.201, p<0.031, presence of drains (r=0.445, p<0.001, postoperative complications (r=0.524, p< 0.001 and hospital stay. Our data confirms that both preoperative, transoperative and postoperative variables prolong the VM and therefore the hospital stay.

  13. Taming the escape dynamics of nonadiabatic time-periodically driven quantum dissipative system within the frame of Wigner formalism

    Energy Technology Data Exchange (ETDEWEB)

    Shit, Anindita [Department of Chemistry, Bengal Engineering and Science University, Shibpur, Howrah 711103 (India); Chattopadhyay, Sudip, E-mail: [Department of Chemistry, Bengal Engineering and Science University, Shibpur, Howrah 711103 (India); Ray Chaudhuri, Jyotipratim, E-mail: [Department of Physics, Katwa College, Katwa, Burdwan 713130 (India)


    Highlights: • Nonadiabatic dynamics of quantum particle under the impact of high-frequency force. • Formulation of time-independent dynamics via Floquet and Kapitza schemes. • Manipulation of external force parameters allows us to control the escape rate. • Increase of (amplitudes/frequency) causes the system to decay faster, in general. • Crossover temperature increases in the presence of the field. - Abstract: Escape under the action of the external modulation constitutes a nontrivial generalization of an conventional Kramers rate because the system is away from thermal equilibrium. A derivation of this result from the point of view of Langevin dynamics in the frame of Floquet theorem in conjunction with the Kapitza–Landau time window (that leads to an attractive description of the time-dependent quantum dynamics in terms of time-independent one) has been provided. The quantum escape rate in the intermediate-to-high and very-high damping regime so obtained analytically using the phase space formalism associated with the Wigner distribution and path-integral formalism bears a quantum correction that depends strongly on the barrier height. It is shown that an increase of (amplitude/frequency) ratio causes the system to decay faster, in general. The crossover temperature between tunneling and thermal activation increases in the presence of field so that quantum effects in the escape are relevant at higher temperatures.

  14. On robust multi-period pre-commitment and time-consistent mean-variance portfolio optimization

    NARCIS (Netherlands)

    F. Cong (Fei); C.W. Oosterlee (Kees)


    textabstractWe consider robust pre-commitment and time-consistent mean-variance optimal asset allocation strategies, that are required to perform well also in a worst-case scenario regarding the development of the asset price. We show that worst-case scenarios for both strategies can be found by

  15. Germination Response of MR 219 Rice Variety to Different Exposure Times and Periods of 2450 MHz Microwave Frequency

    Directory of Open Access Journals (Sweden)

    Daryush Talei


    Full Text Available Germination is a key process in plants' phenological cycles. Accelerating this process could lead to improvment of the seedling growth as well as the cultivation efficiency. To achieve this, the effect of microwave frequency on the germination of rice seeds was examined. The physiological feedbacks of the MR 219 rice variety in terms of seed germination rate (GR, germination percentage (GP, and mean germination time (MGT were analyzed by exposing its seeds to 2450 MHz of microwave frequency for one, four, seven, and ten hours. It was revealed that exposing the seeds to the microwave frequency for 10 hours resulted in the highest GP. This treatment led to 100% of germination after three days with a mean germination time of 2.1 days. Although the other exposure times of microwave frequency caused the moderate effects on germination with a GPa3 ranged from 93% to 98%, they failed to reduce the MGTa3. The results showed that ten-hour exposure times of microwave frequency for six days significantly facilitated and improved the germination indices (primary shoot and root length. Therefore, the technique is expected to benefit the improvement of rice seed germination considering its simplicity and efficacy in increasing the germination percentage and rate as well as the primary shoot and root length without causing any environmental toxicity.

  16. Study of the hovering period and bubble size in fully developed pool nucleate boiling of saturated liquid with a time-dependent heat source

    International Nuclear Information System (INIS)

    Pasamehmetoglu, K.O.; Nelson, R.A.


    In this paper, the bubble behavior in saturated pool boiling with a time-dependent heat source is analyzed. The study is restricted to the period from fully developed nucleate boiling until critical heat flux occurs. The hovering period and the departure volume of the bubble are selected as the characteristic parameters for bubble behavior. These parameters are quantified by solving the equation of motion for an idealized bubble. This equation is solved for cases in which the surface heat flux changes linearly and exponentially as a function of time. After nondimensionalization, the results are compared directly with the results of the steady-state problem. The comparison shows that the transient heat input has practically no effect on the hovering period. However, the transient heat flux causes a decreased volume at bubble departure. The volume decrease is dependent on the severity of the transient. These results are in qualitative agreement with the experimental observation quoted in the literature

  17. Subjective and objective observation of skin graft recovery on Indonesian local cat with different periods of transplantation time. (United States)

    Erwin; Gunanti; Handharyani, Ekowati; Noviana, Deni


    The success of a skin graft in a cat is highly dependent on the granulation formed by the base of recipient bed. Granulation by the base of recipient bed will form after several days after injury. This research aimed to observe subjective and objective profile of skin graft recovery on forelimb of cats with different periods of donor skin placement. Nine male Indonesian local cats aged 1-2 years old, weighing 3-4 kg were divided into three groups. The first surgery for creating defect wound of 2 cm×2 cm in size was performed in the whole group. The wound was left for several days with the respective interval for each group, respectively: Group I (for 2 days), Group II (for 4 days), and Group III (for 6 days). In the whole group, the second surgery was done by the harvesting skin of thoracic area which then applied on recipient bed of respective groups. The donor skin on Group II was accepted faster compared to Group I and Group III. The donor skin did not show color differences compared to surrounding skin, painless, bright red in bleeding test had faster both hair growth and drug absorption. Test toward the size of donor skin and the effect of drugs did not show a significant difference between each group. The observe subjective and objective profile of skin graft recovery on forelimb of cats on Group II were accepted faster compared to Group I and III.

  18. Attributing impacts to emissions traced to major fossil energy and cement producers over specific historical time periods (United States)

    Ekwurzel, B.; Frumhoff, P. C.; Allen, M. R.; Boneham, J.; Heede, R.; Dalton, M. W.; Licker, R.


    Given the progress in climate change attribution research over the last decade, attribution studies can inform policymakers guided by the UNFCCC principle of "common but differentiated responsibilities." Historically this has primarily focused on nations, yet requests for information on the relative role of the fossil energy sector are growing. We present an approach that relies on annual CH4 and CO2 emissions from production through to the sale of products from the largest industrial fossil fuel and cement production company records from the mid-nineteenth century to present (Heede 2014). Analysis of the global trends with all the natural and human drivers compared with a scenario without the emissions traced to major carbon producers over full historical versus select periods of recent history can be policy relevant. This approach can be applied with simple climate models and earth system models depending on the type of climate impacts being investigated. For example, results from a simple climate model, using best estimate parameters and emissions traced to 90 largest carbon producers, illustrate the relative difference in global mean surface temperature increase over 1880-2010 after removing these emissions from 1980-2010 (29-35%) compared with removing these emissions over 1880-2010 (42-50%). The changing relative contributions from the largest climate drivers can be important to help assess the changing risks for stakeholders adapting to and reducing exposure and vulnerability to regional climate change impacts.

  19. Time lag between deformation and seismicity along monogenetic volcanic unrest periods: The case of El Hierro Island (Canary Islands) (United States)

    Lamolda, Héctor; Felpeto, Alicia; Bethencourt, Abelardo


    Between 2011 and 2014 there were at least seven episodes of magmatic intrusion in El Hierro Island, but only the first one led to a submarine eruption in 2011-2012. In order to study the relationship between GPS deformation and seismicity during these episodes, we compare the temporal evolution of the deformation with the cumulative seismic energy released. In some of the episodes both deformation and seismicity evolve in a very similar way, but in others a time lag appears between them, in which the deformation precedes the seismicity. Furthermore, a linear correlation between decimal logarithm of intruded magma volume and decimal logarithm of total seismic energy released along the different episodes has been observed. Therefore, if a future magmatic intrusion in El Hierro Island follows this behavior with a proper time lag, we could have an a priori estimate on the order of magnitude the seismic energy released would reach.


    Directory of Open Access Journals (Sweden)

    Vasile Dr ̆agan


    Full Text Available We investigate the problem for solving a discrete-time periodic gen- eralized Riccati equation with an indefinite sign of the quadratic term. A necessary condition for the existence of bounded and stabilizing solution of the discrete-time Riccati equation with an indefinite quadratic term is derived. The stabilizing solution is positive semidefinite and satisfies the introduced sign conditions. The proposed condition is illustrated via a numerical example.

  1. Detection of Variations in Air Temperature at Different Time Scales During the Period 1889-1998 at Firenze, Italy

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, P.V. [Central Research Institute for Dryland Agriculture, Santoshnagar, Saidabad, Hyderabad, 500059, Andhra Pradesh (India); Bindi, M. [DISAT-UNIFI, P.le delle Cascine 18, 50144, Firenze (Italy); Crisci, A. [LaMMA-Laboratorio per la Meteorologia, Climatologia e la Modellistica Ambientale, Campi Bisenzio (Italy); Maracchi, G. [IATA-CNR, P.le delle Cascine 18, 50144 Firenze (Italy)


    In an attempt to contribute to studies on global climatic change, 110 years of temperature data for Firenze, Italy, were analysed. Means and trends of annual and monthly temperatures (minimum, maximum and average) were analysed at three different time scales: short (20 years), medium (36-38 years) and long (55 years). Comparative changes in extreme events viz. frosts in the first and second parts of the 20th century were also analysed. At short time scales, climatic change was found in minimum and average temperatures but not in maximum temperatures. At all three time scales, the annual means of minimum, maximum and average temperatures were significantly warmer in the last part than in the early part of the 20th century. The monthly mean temperatures showed significant warming of winter months. Over the last four decades, minimum, maximum and average temperatures had warmed by 0.4, 0.43 and 0.4C per decade, respectively, and if this trend continues, they will be warmer by 4C by the end of the 21st century. The significant decline in days with subzero temperatures and frosts in the last half of the 20th century, further substantiated the occurrence of climate change at this site.

  2. Effect of Number of Spermatozoa, Oviduct Condition and Timing of Artificial Insemination on Fertility and Fertile Period of Kampung Rooster Spermatozoa

    Directory of Open Access Journals (Sweden)

    DM Saleh


    Full Text Available Abstract. This study was carried out to determine the optimum fertility and fertile period using the number of spermatozoa, oviduct condition and timing of insemination of native rooster spermatozoa. Ninety six commercial Isa brown pullets and nine kampung roosters were used in this study in a 3×2×2 factorial arrangement with one bird in a cage constituting a unit. The factor levels were the number of spermatozoa (50, 100 and 150 million/0.1 ml, oviduct condition (hard-shelled eggs and free hard-shelled eggs, and timing of artificial insemination (in the morning, at 7 AM and in the afternoon, at 4 PM.  The results showed that among the treatments there was no significant interaction to fertility and fertile period. Insemination with 50 million sperm number seemed to be the same result with the other 2 treatments. Oviduct condition had a highly significant difference on fertility and fertile period percentage, and timing of insemination did not differ between morning and afternoon.  In conclusion, the only oviduct condition (free hard-shelled eggs was the best results for insemination in terms of fertility and fertile period of native roosters.  It is recommended that for the maximum fertility and fertile period, hens should be inseminated with 50 million spermatozoa, free of hard-shelled eggs and insemination performed in the morning or in the afternoon.   Keywords: timing of artificial insemination, fertility, fertile period, semen dose, oviduct condition Animal Production 14(1:32-36, January 2012

  3. On a Batch Arrival Queuing System Equipped with a Stand-by Server during Vacation Periods or the Repairs Times of the Main Server

    Directory of Open Access Journals (Sweden)

    Rehab F. Khalaf


    Full Text Available We study a queuing system which is equipped with a stand-by server in addition to the main server. The stand-by server provides service to customers only during the period of absence of the main server when either the main server is on a vacation or it is in the state of repairs due to a sudden failure from time to time. The service times, vacation times, and repair times are assumed to follow general arbitrary distributions while the stand-by service times follow exponential distribution. Supplementary variables technique has been used to obtain steady state results in explicit and closed form in terms of the probability generating functions for the number of customers in the queue, the average number of customers, and the average waiting time in the queue while the MathCad software has been used to illustrate the numerical results in this work.

  4. Instabilities in fluid layers and in reaction-diffusion systems: Steady states, time-periodic solutions, non-periodic attractors, and related convective and otherwise non-linear phenomena

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Velarde, M


    Thermo convective instabilities in horizontal fluid layers are discussed with emphasis on the Rayleigh-Bernard model problem. Steady solutions and time-dependent phenomena (relaxation oscillations and transition to turbulence) are studied within the nonlinear Boussinesq-Oberbeck approximation. Homogeneous steady solutions, limit cycles, and inhomogeneous (ordered) spatial structures are also studied in simple reaction-diffusion systems. Lastly, the non-periodic attractor that appears at large Rayleigh numbers in the truncated Boussinesq-Oberbeck model of Lorenz, is constructed, and a discussion of turbulent behavior is given. (Author) 105 refs.

  5. Instabilities in fluid layers and in reaction-diffusion systems: Steady states, time-periodic solutions, non-periodic attractors, and related convective and otherwise non-linear phenomena

    International Nuclear Information System (INIS)

    Garcia Velarde, M.


    Thermoconvective instabilities in horizontal fluid layers are discussed with emphasis on the Rayleigh-Benard model problem. Steady solutions and time-dependent phenomena (relaxation oscillations and transition to turbulence) are studied within the nonlinear Boussinesq-Oberbeck approximation. Homogeneous steady solutions, limit cycles, and inhomogeneous (ordered) spatial structures are also studied in simple reaction-diffusion systems. Lastly, the non-periodic attractor that appears at large Rayleigh numbers in the truncated Boussinesq-Oberbeck model of Lorenz, is constructed, and a discussion of turbulent behavior is given. (author) [es

  6. Instabilities in fluid layers and in reaction-diffusion systems: Steady states, time-periodic solutions, non-periodic attractors, and related convective and otherwise non-linear phenomena

    International Nuclear Information System (INIS)

    Garcia Velarde, M.


    Thermo convective instabilities in horizontal fluid layers are discussed with emphasis on the Rayleigh-Bernard model problem. Steady solutions and time-dependent phenomena (relaxation oscillations and transition to turbulence) are studied within the nonlinear Boussinesq-Oberbeck approximation. Homogeneous steady solutions, limit cycles, and inhomogeneous (ordered) spatial structures are also studied in simple reaction-diffusion systems. Lastly, the non-periodic attractor that appears at large Rayleigh numbers in the truncated Boussinesq-Oberbeck model of Lorenz, is constructed, and a discussion of turbulent behavior is given. (Author) 105 refs

  7. Subjective and objective observation of skin graft recovery on Indonesian local cat with different periods of transplantation time

    Directory of Open Access Journals (Sweden)



    Full Text Available Aim: The success of a skin graft in a cat is highly dependent on the granulation formed by the base of recipient bed. Granulation by the base of recipient bed will form after several days after injury. This research aimed to observe subjective and objective profile of skin graft recovery on forelimb of cats with different periods of donor skin placement. Materials and Methods: Nine male Indonesian local cats aged 1-2 years old, weighing 3-4 kg were divided into three groups. The first surgery for creating defect wound of 2 cm×2 cm in size was performed in the whole group. The wound was left for several days with the respective interval for each group, respectively: Group I (for 2 days, Group II (for 4 days, and Group III (for 6 days. In the whole group, the second surgery was done by the harvesting skin of thoracic area which then applied on recipient bed of respective groups. Result: The donor skin on Group II was accepted faster compared to Group I and Group III. The donor skin did not show color differences compared to surrounding skin, painless, bright red in bleeding test had faster both hair growth and drug absorption. Test toward the size of donor skin and the effect of drugs did not show a significant difference between each group. Conclusion: The observe subjective and objective profile of skin graft recovery on forelimb of cats on Group II were accepted faster compared to Group I and III.

  8. Risk factors for hyperglycemia in pregnancy in the DALI study differ by period of pregnancy and OGTT time point

    DEFF Research Database (Denmark)

    Mendoza, Lilian C; Harreiter, Jürgen; Simmons, David


    maternal and current pregnancy characteristics. STATISTICAL ANALYSIS: Multivariate logistic regression. RESULTS Clinical characteristics independently associated with GDM/overt diabetes were: at ≤19+6 weeks, previous abnormal glucose tolerance (OR 3.11; CI95 1.41-6.85), previous GDM (OR 2.22; CI95 1......; at 35-37 weeks, maternal height (OR 0.41; CI95 0.20-0.87 for upper tertile). Clinical characteristics independently associated with GDM/overt diabetes differed by OGTT time point (e.g. at ≤19+6 weeks, neck circumference was associated with abnormal fasting but not postchallenge glucose). CONCLUSION...

  9. Differences in night-time and daytime ambulatory blood pressure when diurnal periods are defined by self-report, fixed-times, and actigraphy: Improving the Detection of Hypertension study. (United States)

    Booth, John N; Muntner, Paul; Abdalla, Marwah; Diaz, Keith M; Viera, Anthony J; Reynolds, Kristi; Schwartz, Joseph E; Shimbo, Daichi


    To determine whether defining diurnal periods by self-report, fixed-time, or actigraphy produce different estimates of night-time and daytime ambulatory blood pressure (ABP). Over a median of 28 days, 330 participants completed two 24-h ABP and actigraphy monitoring periods with sleep diaries. Fixed night-time and daytime periods were defined as 0000-0600 h and 1000-2000 h, respectively. Using the first ABP period, within-individual differences for mean night-time and daytime ABP and kappa statistics for night-time and daytime hypertension (systolic/diastolic ABP≥120/70 mmHg and ≥135/85 mmHg, respectively) were estimated comparing self-report, fixed-time, or actigraphy for defining diurnal periods. Reproducibility of ABP was also estimated. Within-individual mean differences in night-time systolic ABP were small, suggesting little bias, when comparing the three approaches used to define diurnal periods. The distribution of differences, represented by 95% confidence intervals (CI), in night-time systolic and diastolic ABP and daytime systolic and diastolic ABP was narrowest for self-report versus actigraphy. For example, mean differences (95% CI) in night-time systolic ABP for self-report versus fixed-time was -0.53 (-6.61, +5.56) mmHg, self-report versus actigraphy was 0.91 (-3.61, +5.43) mmHg, and fixed-time versus actigraphy was 1.43 (-5.59, +8.46) mmHg. Agreement for night-time and daytime hypertension was highest for self-report versus actigraphy: kappa statistic (95% CI) = 0.91 (0.86,0.96) and 1.00 (0.98,1.00), respectively. The reproducibility of mean ABP and hypertension categories was similar using each approach. Given the high agreement with actigraphy, these data support using self-report to define diurnal periods on ABP monitoring. Further, the use of fixed-time periods may be a reasonable alternative approach.

  10. Improvement of Ka-band satellite link availability for real-time IP-based video contribution

    Directory of Open Access Journals (Sweden)

    G. Berretta


    Full Text Available New High Throughput Satellite (HTS systems allow high throughput IP uplinks/contribution at Ka-band frequencies for relatively lower costs when compared to broadcasting satellite uplinks at Ku band. This technology offers an advantage for live video contribution from remote areas, where the terrestrial infrastructure may not be adequate. On the other hand, the Ka-band is more subject to impairments due to rain or bad weather. This paper addresses the target system specification and provides an optimized approach for the transmission of IP-based video flows through HTS commercial services operating at Ka-band frequencies. In particular, the focus of this study is on the service requirements and the propagation analysis that provide a reference architecture to improve the overall link availability. The approach proposed herein leads to the introduction of a new concept of live service contribution using pairs of small satellite antennas and cheap satellite terminals.

  11. Experimental test on the use of MS-222 for ostracod anaesthesia: concentration, immersion period and recovery time

    Directory of Open Access Journals (Sweden)

    Francesc MEZQUITA


    Full Text Available Anaesthesia of animals may be useful for different purposes, particularly for veterinary reasons or in experimental research, for manipulation or treatment of immobilized but alive animals. Its use in crustaceans is not uncommon, but it has never been described for Ostracoda. We provide brief and preliminary guidelines on the use of the tricaine mesylate (MS-222 on the widespread freshwater ostracod Eucypris virens and we show that this compound is an effective anaesthetic used as a bath treatment at minimum concentrations of 500 mg L-1. This value is considerably higher than that recommended for other aquatic animals like fish. Recovery time, ranging from 5 to 15 minutes, is mostly determined by anaesthetic bath concentration, while bath duration influenced to a lesser extent. Anaesthesia induced with MS-222 can prove useful for minute manipulation of living ostracods e.g. for identification, marking or image capture under the microscope.

  12. The “green wave” mode production on the two-lane highways during the construction works time period

    Directory of Open Access Journals (Sweden)

    А. Berezhnoy


    Full Text Available In the paper, the problem of a bi-directional “green wave” mode production is considered for the vehicle flows motion on two-lane highways during the conducting of construction works. The solution of the given task allows to develop practical recommendations for the sphere of the construction works management on two-lane roads and country highways, and also to raise traffic control efficiency in the pointed conditions. The comparative analysis of possible traffic regulation modes for the set scheme of road construction works sites and the estimation of their effi ciency is performed, the test of a hypothesis regarding the possibility of a bi-directional “green wave” mode realization is carried out, and calculation of traffic lights signal control phases time is performed.

  13. Time-critical database condition data handling in the CMS experiment during the first data taking period

    CERN Document Server

    Di Guida, Salvatore


    Automatic, synchronous and of course reliable population of the condition databases is critical for the correct operation of the online selection as well as of the offline reconstruction and analysis of data. In this complex infrastructure, monitoring and fast detection of errors is a very challenging task. To recover the system and to put it in a safe state requires spotting a faulty situation within strict time constraints. We will describe here the system put in place in the CMS experiment to automate the processes that populate centrally the Condition Databases and make condition data promptly available both online for the high-level trigger and offline for reconstruction. The data are automatically collected using centralized jobs or are ``dropped'' by the users in dedicate services (offline and online drop-box), which synchronize them and take care of writing them into the online database. Then they are automatically streamed to the offline database, and thus are immediately acce...

  14. An assessment of issues related to determination of time periods required for isolation of high level waste

    International Nuclear Information System (INIS)

    Cohen, J.J.; Daer, G.R.; Vogt, D.K.; Woolfolk, S.W.


    A commonly held perception is that disposal of spent nuclear fuel or high-level waste presents a risk of unprecedented duration. In 40 CFR 191, the EPA requires that projected releases of radioactivity be limited for 10,000 years after disposal with the intent that risks from the disposal repository be no greater than those from the uranium ore deposit from which the nuclear fuel was originally extracted. This study reviews issues involved in assessing compliance with the requirement. The determination of compliance is assumption dependent primarily due to uncertainties in dosi-metric data, and relative availability of the radioactivity for environmental transport and eventual assimilation by humans. A conclusion of this study is that, in time, a spent fuel disposal repository such as the projected Yucca Mountain Project Facility will become less hazardous than the original ore deposit

  15. Tracing the Inter-Hemispheric Coupling During Polar Summer Periods of 2002-2010 Using TIMED/SABER Measurements (United States)

    Goldberg, Richard; Feoflow, Artem; Pesnell, Dean; Kutepov, Alexander


    It has been found that for more than one polar summer season between 2002-2010, the northern polar mesospheric region near and above the mesospheric maximum was warmer than normal. The strongest warming effect of this type was observed to occur during northern summer 2002. Theoretical studies have implied that these "anomalies" were preceded by unusual dynamical processes occurring in the southern hemisphere. We have analyzed temperature distributions measured by the SABER limb scanning infrared radiometer aboard the NASA TIMED satellite between 2002-2010 at altitudes from 15 to 110 km and for latitudes between 83 deg. S to 83 deg. N. We describe the approach to trace the inter-hemispheric temperature correlatoins and to identify the global features that were unique for the "anomalous" northern polar summers.

  16. Breastfeeding Initiation and Duration in First-Time Mothers: Exploring the Impact of Father Involvement in the Early Post-Partum Period

    Directory of Open Access Journals (Sweden)

    Theresa Hunter


    Full Text Available Background: The early post-partum period is a crucial time for breastfeeding support. Mothers who have physical and emotional support during this period are more likely to be successful in breastfeeding. This study examined the relationship between father involvement and support for breast feeding initiation and duration in first-time mothers. Methods: Overall, 146 women who attended a childbirth education class or breastfeeding course at BABS were asked to fill out the Childbirth Experiences Survey, which explored key topics such as (1 breastfeeding initiation, (2 early post-partum breastfeeding, (3 breastfeeding plan, (4 post-partum breastfeeding support and (5 breast feeding duration. This was a voluntary self-reported questionnaire. The surveys were completed by the mothers during the post-partum period. Results: 45.9% (n=67 of mothers received helped from their husband or partner with breastfeeding while in the hospital, while 54.1% (n=79 of mothers did not receive support from their partners. Mothers who received early post-partum breastfeeding support were more likely to continue breastfeeding after leaving the hospital. Conclusion: First-time mothers who identified as having breastfeeding support from their partners, the infant’s father, during the early post-partum period were more likely to initiate breastfeeding and had longer breastfeeding durations.

  17. Reference gene selection for real-time quantitative PCR analysis of the mouse uterus in the peri-implantation period.

    Directory of Open Access Journals (Sweden)

    Pengfei Lin

    Full Text Available The study of uterine gene expression patterns is valuable for understanding the biological and molecular mechanisms that occur during embryo implantation. Real-time quantitative RT-PCR (qRT-PCR is an extremely sensitive technique that allows for the precise quantification of mRNA abundance; however, selecting stable reference genes suitable for the normalization of qRT-PCR data is required to avoid the misinterpretation of experimental results and erroneous analyses. This study employs several mouse models, including an early pregnancy, a pseudopregnancy, a delayed implantation and activation, an artificial decidualization and a hormonal treatment model; ten candidate reference genes (PPIA, RPLP0, HPRT1, GAPDH, ACTB, TBP, B2M, 18S, UBC and TUBA that are found in uterine tissues were assessed for their suitability as internal controls for relative qRT-PCR quantification. GeNorm(PLUS, NormFinder, and BestKeeper were used to evaluate these candidate reference genes, and all of these methods identified RPLP0 and GAPDH as the most stable candidates and B2M and 18S as the least stable candidates. However, when the different models were analyzed separately, the reference genes exhibited some variation in their expression levels.

  18. Time-critical Database Condition Data Handling in the CMS Experiment During the First Data Taking Period

    International Nuclear Information System (INIS)

    Cavallari, Francesca; Gruttola, Michele de; Di Guida, Salvatore; Innocente, Vincenzo; Pfeiffer, Andreas; Govi, Giacomo; Pierro, Antonio


    Automatic, synchronous and reliable population of the condition databases is critical for the correct operation of the online selection as well as of the offline reconstruction and analysis of data. In this complex infrastructure, monitoring and fast detection of errors is a very challenging task. In this paper, we describe the CMS experiment system to process and populate the Condition Databases and make condition data promptly available both online for the high-level trigger and offline for reconstruction. The data are automatically collected using centralized jobs or are 'dropped' by the users in dedicated services (offline and online drop-box), which synchronize them and take care of writing them into the online database. Then they are automatically streamed to the offline database, and thus are immediately accessible offline worldwide. The condition data are managed by different users using a wide range of applications. In normal operation the database monitor is used to provide simple timing information and the history of all transactions for all database accounts, and in the case of faults it is used to return simple error messages and more complete debugging information.

  19. Inter-Hemispheric Coupling During Northern Polar Summer Periods of 2002-2010 using TIMED/SABER Measurements (United States)

    Goldberg, Richard A.; Feofilov, A. G.; Pesnell, W. D.; Kutepov, A. A.


    It has been found that for more than one polar summer season between 2002-2010, the northern polar mesospheric region near and above about 80 km was warmer than normal. The strongest warming effect of this type was observed to occur during northern summer 2002. Theoretical studies have implied that these "anomalies" were preceded by unusual dynamical processes in the southern hemisphere. We have analyzed temperature distributions measured by the SABER limb scanning infrared radiometer aboard the NASA TIMED satellite between 2002-2010 at altitudes from 15 to 110 km and for latitudes between 83 S to 83 N. We describe the approach to trace the inter-hemispheric temperature correlations demonstrating the global features that were unique for the "anomalous" northern polar summers. From our analysis of SABER data from 2002-2010, the anomalous heating for the northern mesopause region during northern summer was accompanied by stratospheric heating in the equatorial region. In the winter hemisphere it is accompanied by heating in the lower stratosphere and mesopause region, and cooling in the stratopause region. Also, all the elements of the temperature anomaly structure appear to develop and fade away nearly simultaneously, thereby suggesting either a global influence or a rapid exchange.

  20. Evaluating the coefficient of thermal expansion using time periods of minimal thermal gradient for a temperature driven structural health monitoring (United States)

    Reilly, J.; Abdel-Jaber, H.; Yarnold, M.; Glisic, B.


    Structural Health Monitoring aims to characterize the performance of a structure from a combination of recorded sensor data and analytic techniques. Many methods are concerned with quantifying the elastic response of the structure, treating temperature changes as noise in the analysis. While these elastic profiles do demonstrate a portion of structural behavior, thermal loads on a structure can induce comparable strains to elastic loads. Understanding this relationship between the temperature of the structure and the resultant strain and displacement can provide in depth knowledge of the structural condition. A necessary parameter for this form of analysis is the Coefficient of Thermal Expansion (CTE). The CTE of a material relates the amount of expansion or contraction a material undergoes per degree change in temperature, and can be determined from temperature-strain relationship given that the thermal strain can be isolated. Many times with concrete, the actual amount of expansion with temperature in situ varies from the given values for the CTE due to thermally generated elastic strain, which complicates evaluation of the CTE. To accurately characterize the relationship between temperature and strain on a structure, the actual thermal behavior of the structure needs to be analyzed. This rate can vary for different parts of a structure, depending on boundary conditions. In a case of unrestrained structures, the strain in the structure should be linearly related to the temperature change. Thermal gradients in a structure can affect this relationship, as they induce curvature and deplanations in the cross section. This paper proposes a method that addresses these challenges in evaluating the CTE.

  1. X-Ray Timing Analysis of Cyg X-3 Using AstroSat/LAXPC: Detection of Milli-hertz Quasi-periodic Oscillations during the Flaring Hard X-Ray State

    Energy Technology Data Exchange (ETDEWEB)

    Pahari, Mayukh; Misra, Ranjeev [Inter-University Center for Astronomy and Astrophysics, Ganeshkhind, Pune 411007 (India); Antia, H M; Yadav, J S; Chauhan, Jai Verdhan; Chitnis, V R; Dedhia, Dhiraj; Katoch, Tilak; Madhwani, P; Shah, Parag [Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400005 (India); Agrawal, P C [UM-DAE Center of Excellence for Basic Sciences, University of Mumbai, Kalina, Mumbai 400098 (India); Manchanda, R K [University of Mumbai, Kalina, Mumbai 400098 (India); Paul, B, E-mail: [Department of Astronomy and Astrophysics, Raman Research Institute, Bengaluru 560080 (India)


    We present here results from the X-ray timing and spectral analysis of the X-ray binary Cyg X-3 using observations from the Large Area X-ray proportional Counter on board AstroSat . Consecutive light curves observed over a period of one year show the binary orbital period of 17253.56 ± 0.19 s. Another low-amplitude, slow periodicity of the order of 35.8 ± 1.4 days is observed, which may be due to the orbital precession as suggested earlier by Molteni et al. During the rising binary phase, power density spectra from different observations during the flaring hard X-ray state show quasi-periodic oscillations (QPOs) at ∼5–8 mHz, ∼12–14 mHz, and ∼18–24 mHz frequencies at the minimum confidence of 99%. However, during the consecutive binary decay phase, no QPO is detected up to 2 σ significance. Energy-dependent time-lag spectra show soft lag (soft photons lag hard photons) at the mHz QPO frequency and the fractional rms of the QPO increases with the photon energy. During the binary motion, the observation of mHz QPOs during the rising phase of the flaring hard state may be linked to the increase in the supply of the accreting material in the disk and corona via stellar wind from the companion star. During the decay phase, the compact source moves in the outer wind region causing the decrease in supply of material for accretion. This may cause weakening of the mHz QPOs below the detection limit. This is also consistent with the preliminary analysis of the orbital phase-resolved energy spectra presented in this paper.

  2. Evaluating Computer Screen Time and Its Possible Link to Psychopathology in the Context of Age: A Cross-Sectional Study of Parents and Children. (United States)

    Segev, Aviv; Mimouni-Bloch, Aviva; Ross, Sharon; Silman, Zmira; Maoz, Hagai; Bloch, Yuval


    Several studies have suggested that high levels of computer use are linked to psychopathology. However, there is ambiguity about what should be considered normal or over-use of computers. Furthermore, the nature of the link between computer usage and psychopathology is controversial. The current study utilized the context of age to address these questions. Our hypothesis was that the context of age will be paramount for differentiating normal from excessive use, and that this context will allow a better understanding of the link to psychopathology. In a cross-sectional study, 185 parents and children aged 3-18 years were recruited in clinical and community settings. They were asked to fill out questionnaires regarding demographics, functional and academic variables, computer use as well as psychiatric screening questionnaires. Using a regression model, we identified 3 groups of normal-use, over-use and under-use and examined known factors as putative differentiators between the over-users and the other groups. After modeling computer screen time according to age, factors linked to over-use were: decreased socialization (OR 3.24, Confidence interval [CI] 1.23-8.55, p = 0.018), difficulty to disengage from the computer (OR 1.56, CI 1.07-2.28, p = 0.022) and age, though borderline-significant (OR 1.1 each year, CI 0.99-1.22, p = 0.058). While psychopathology was not linked to over-use, post-hoc analysis revealed that the link between increased computer screen time and psychopathology was age-dependent and solidified as age progressed (p = 0.007). Unlike computer usage, the use of small-screens and smartphones was not associated with psychopathology. The results suggest that computer screen time follows an age-based course. We conclude that differentiating normal from over-use as well as defining over-use as a possible marker for psychiatric difficulties must be performed within the context of age. If verified by additional studies, future research should integrate

  3. Experimental evaluation of the MIT-SNL period-generated minimum time control laws for the rapid adjustment of reactor power

    International Nuclear Information System (INIS)

    Bernard, J.A.; Kwok, K.S.; Menadier, P.T.; Thome, F.V.; Wyant, F.J.


    The rapid adjustment of reactor neutronic power has recently been achieved by developing control laws that determine the actuator mechanism velocity necessary to produce a specified reactor period. Designated as the 'MIT-SNL Period-Generated Minimum Time Control Laws,' these relations are closed-form expressions of general applicability. In particular, if there is no limitation on the available rate of change of reactivity, these laws can be used to achieve virtually any desired power profile including time optimal ones. The innovative aspect of these laws is that the rate of change of reactivity rather than the reactivity itself is used as the control signal. For example, relative to a time-optimal response, these laws function by altering the rate of change of reactivity so that the instantaneous period is stepped from infinity to its minimum allowed value, held at that value until the desired power level is attained, and then stepped back to infinity. The response is time-optimal because the power adjustment is continuously made at the maximum allowed rate

  4. Improvement in fatigue during Natalizumab treatment is linked to improvement in depression and day-time sleepiness

    Directory of Open Access Journals (Sweden)

    Iris-Katharina ePenner


    Full Text Available Background: Fatigue is a frequent symptom in multiple sclerosis (MS and often interrelated with depression and sleep disorders making symptomatic treatment decisions difficult. In the single-arm, observational phase IV TYNERGY study, relapsing-remitting MS patients showed a clinically meaningful decrease in fatigue over one year of treatment with natalizumab. Objective: To evaluate whether fatigue improvement might be directly linked to improved depression and daytime sleepiness. Methods: Patients were assessed regarding fatigue, depression, and daytime sleepiness. The relation between changes of the two latter symptoms and changes in fatigue was analysed. Results: After one year of natalizumab treatment, the majority of patients (>92% remained stable or improved in total, motor and cognitive fatigue. Proportion of patients without depression increased by 17% while proportions of mildly depressed patients or patients with potential major depression decreased by 5% and 12%, respectively. Proportion of patients classified as not being sleepy increased by 13% while proportions of sleepy and very sleepy patients decreased by 11% and 2%, respectively. Most importantly, improved depression and sleepiness were significantly related to improved fatigue. Conclusion: Our findings highlight the importance of patient-reported outcomes in identifying potential benefits of drug treatment beyond its well-established effects on disease activity and disability progression.

  5. Modal Analysis in Periodic, Time-Varying Systems with emphasis to the Coupling between Flexible Rotating Beams and Non-Rotating Flexible Structures

    DEFF Research Database (Denmark)

    Saracho, C. M.; Santos, Ilmar


    The analysis of dynamical response of a system built by a non-rotating structure coupled to flexible rotating beams is the purpose of this work. The effect of rotational speed upon the beam natural frequencies is well-known, so that an increase in the angular speeds leads to an increase in beam...... natural frequencies, the so-called centrifugal stiffening. The equations of motion of such a global system present matrices with time-depending coefficients, which vary periodically with the angular rotor speed, and introduce parametric vibrations into the system response. The principles of modal analysis...... for time-invariant linear systems are expanded to investigate time-varying systems. Concepts as eigenvalues and eigenvectors, which in this special case are also time-varying, are used to analyse the dynamical response of global system. The time-varying frequencies and modes are also illustrated....


    The subject of this presentation is forest vegetation dynamics as observed by the TERRA spacecraft's Moderate-Resolution Imaging Spectroradiometer (MODIS) and Landsat Thematic Mapper, and complimentary in situ time series measurements of forest canopy metrics related to Leaf Area...

  7. Links between ocean properties, ice cover, and plankton dynamics on interannual time scales in the Canadian Arctic Archipelago (United States)

    Hamilton, James M.; Collins, Kate; Prinsenberg, Simon J.


    A decade of instrumented mooring data from Barrow Strait in the eastern Canadian Arctic Archipelago reveals connections between sea ice, water characteristics, and zooplankton dynamics on interannual time scales. On the North side of the Strait, the timing of breakup is positively related to the timing of freezeup in the previous year and negatively related to spring water temperature. This suggests that an early freezeup insulates the ocean from a cold autumn atmosphere, allowing heat to be retained until spring when it contributes to early sea ice erosion. There is also a very strong negative association between the timing of freezeup and late summer salinity, suggesting that monitoring of salinity in real time could be used to predict freezeup. A zooplankton biomass index derived from acoustic Doppler current profiler echo intensity data is used to demonstrate that on the North side there are also strong connections between early summer water temperature and the start, length, and productivity of the zooplankton growth season. On the South side of the Strait where currents are stronger, the relationships seen on the North side were not observed. But here integrated zooplankton biomass index and measured currents are used to identify interannual variability in the zooplankton biomass being delivered downstream into Lancaster Sound. Also on the South side, two yearlong records of daily fluorescence profiles reveal a large difference in the phytoplankton biomass being delivered downstream between years and demonstrate a strong relationship between the timing of the spring phytoplankton bloom and that of breakup.

  8. Analysis of the impact of crude oil price fluctuations on China's stock market in different periods-Based on time series network model (United States)

    An, Yang; Sun, Mei; Gao, Cuixia; Han, Dun; Li, Xiuming


    This paper studies the influence of Brent oil price fluctuations on the stock prices of China's two distinct blocks, namely, the petrochemical block and the electric equipment and new energy block, applying the Shannon entropy of information theory. The co-movement trend of crude oil price and stock prices is divided into different fluctuation patterns with the coarse-graining method. Then, the bivariate time series network model is established for the two blocks stock in five different periods. By joint analysis of the network-oriented metrics, the key modes and underlying evolutionary mechanisms were identified. The results show that the both networks have different fluctuation characteristics in different periods. Their co-movement patterns are clustered in some key modes and conversion intermediaries. The study not only reveals the lag effect of crude oil price fluctuations on the stock in Chinese industry blocks but also verifies the necessity of research on special periods, and suggests that the government should use different energy policies to stabilize market volatility in different periods. A new way is provided to study the unidirectional influence between multiple variables or complex time series.

  9. Evaluation of the Usefulness of Restricted Respiratory Period at the Time of Radiotherapy for Non-Small Cell Lung Cancer Patient

    Energy Technology Data Exchange (ETDEWEB)

    Park, So Yeon; Ahn, Jong Ho; Kim, Yung Il; Kim, Jin Man; Choi, Byung Ki; Pyo, Hong Ryul; Song, Ki Won [Dept. of Radiation Oncology, Samsung Medical Center, Seoul (Korea, Republic of); Suh, Jung Min [Dept. of Radiological Science, Daewon University Colloge, Jecheon (Korea, Republic of)


    It is essential to minimize the movement of tumor due to respiratory movement at the time of respiration controlled radiotherapy of non-small cell lung cancer patient. Accordingly, this Study aims to evaluate the usefulness of restricted respiratory period by comparing and analyzing the treatment plans that apply free and restricted respiration period respectively. After having conducted training on 9 non-small cell lung cancer patients (tumor n=10) from April to December 2011 by using 'signal monitored-breathing (guided- breathing)' method for the 'free respiratory period' measured on the basis of the regular respiratory period of the patents and 'restricted respiratory period' that was intentionally reduced, total of 10 CT images for each of the respiration phases were acquired by carrying out 4D CT for treatment planning purpose by using RPM and 4-dimensional computed tomography simulator. Visual gross tumor volume (GTV) and internal target volume (ITV) that each of the observer 1 and observer 2 has set were measured and compared on the CT image of each respiratory interval. Moreover, the amplitude of movement of tumor was measured by measuring the center of mass (COM) at the phase of 0% which is the end-inspiration (EI) and at the phase of 50% which is the end-exhalation (EE). In addition, both observers established treatment plan that applied the 2 respiratory periods, and mean dose to normal lung (MDTNL) was compared and analyzed through dose-volume histogram (DVH). Moreover, normal tissue complication probability (NTCP) of the normal lung volume was compared by using dose-volume histogram analysis program (DVH analyzer v.1) and statistical analysis was performed in order to carry out quantitative evaluation of the measured data. As the result of the analysis of the treatment plan that applied the 'restricted respiratory period' of the observer 1 and observer 2, there was reduction rate of 38.75% in the 3-dimensional

  10. Evaluation of the Usefulness of Restricted Respiratory Period at the Time of Radiotherapy for Non-Small Cell Lung Cancer Patient

    International Nuclear Information System (INIS)

    Park, So Yeon; Ahn, Jong Ho; Kim, Yung Il; Kim, Jin Man; Choi, Byung Ki; Pyo, Hong Ryul; Song, Ki Won; Suh, Jung Min


    It is essential to minimize the movement of tumor due to respiratory movement at the time of respiration controlled radiotherapy of non-small cell lung cancer patient. Accordingly, this Study aims to evaluate the usefulness of restricted respiratory period by comparing and analyzing the treatment plans that apply free and restricted respiration period respectively. After having conducted training on 9 non-small cell lung cancer patients (tumor n=10) from April to December 2011 by using 'signal monitored-breathing (guided- breathing)' method for the 'free respiratory period' measured on the basis of the regular respiratory period of the patents and 'restricted respiratory period' that was intentionally reduced, total of 10 CT images for each of the respiration phases were acquired by carrying out 4D CT for treatment planning purpose by using RPM and 4-dimensional computed tomography simulator. Visual gross tumor volume (GTV) and internal target volume (ITV) that each of the observer 1 and observer 2 has set were measured and compared on the CT image of each respiratory interval. Moreover, the amplitude of movement of tumor was measured by measuring the center of mass (COM) at the phase of 0% which is the end-inspiration (EI) and at the phase of 50% which is the end-exhalation (EE). In addition, both observers established treatment plan that applied the 2 respiratory periods, and mean dose to normal lung (MDTNL) was compared and analyzed through dose-volume histogram (DVH). Moreover, normal tissue complication probability (NTCP) of the normal lung volume was compared by using dose-volume histogram analysis program (DVH analyzer v.1) and statistical analysis was performed in order to carry out quantitative evaluation of the measured data. As the result of the analysis of the treatment plan that applied the 'restricted respiratory period' of the observer 1 and observer 2, there was reduction rate of 38.75% in the 3-dimensional direction movement of the tumor in

  11. Not the time or the place: the missing spatio-temporal link in publicly available genetic data. (United States)

    Pope, Lisa C; Liggins, Libby; Keyse, Jude; Carvalho, Silvia B; Riginos, Cynthia


    Genetic data are being generated at unprecedented rates. Policies of many journals, institutions and funding bodies aim to ensure that these data are publicly archived so that published results are reproducible. Additionally, publicly archived data can be 'repurposed' to address new questions in the future. In 2011, along with other leading journals in ecology and evolution, Molecular Ecology implemented mandatory public data archiving (the Joint Data Archiving Policy). To evaluate the effect of this policy, we assessed the genetic, spatial and temporal data archived for 419 data sets from 289 articles in Molecular Ecology from 2009 to 2013. We then determined whether archived data could be used to reproduce analyses as presented in the manuscript. We found that the journal's mandatory archiving policy has had a substantial positive impact, increasing genetic data archiving from 49 (pre-2011) to 98% (2011-present). However, 31% of publicly archived genetic data sets could not be recreated based on information supplied in either the manuscript or public archives, with incomplete data or inconsistent codes linking genetic data and metadata as the primary reasons. While the majority of articles did provide some geographic information, 40% did not provide this information as geographic coordinates. Furthermore, a large proportion of articles did not contain any information regarding date of sampling (40%). Although the inclusion of spatio-temporal data does require an increase in effort, we argue that the enduring value of publicly accessible genetic data to the molecular ecology field is greatly compromised when such metadata are not archived alongside genetic data. © 2015 John Wiley & Sons Ltd.

  12. Moderate reagent mixing on an orbital shaker reduces the incubation time of enzyme-linked immunosorbent assay. (United States)

    Kumar, Saroj; Ahirwar, Rajesh; Rehman, Ishita; Nahar, Pradip


    Rapid diagnostic tests can be developed using ELISA for detection of diseases in emergency conditions. Conventional ELISA takes 1-2 days, making it unsuitable for rapid diagnostics. Here, we report the effect of reagents mixing via shaking or vortexing on the assay timing of ELISA. A 48-min protocol of ELISA involving 12-min incubations with reagent mixing at 750 rpm for every step was optimized. Contrary to this, time-optimized control ELISA performed without mixing produced similar results in 8 h, leaving a time gain of 7 h using the developed protocol. Collectively, the findings suggest the development of ELISA-based rapid diagnostics. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Non-equilibrium repressor binding kinetics link DNA damage dose to transcriptional timing within the SOS gene network. (United States)

    Culyba, Matthew J; Kubiak, Jeffrey M; Mo, Charlie Y; Goulian, Mark; Kohli, Rahul M


    Biochemical pathways are often genetically encoded as simple transcription regulation networks, where one transcription factor regulates the expression of multiple genes in a pathway. The relative timing of each promoter's activation and shut-off within the network can impact physiology. In the DNA damage repair pathway (known as the SOS response) of Escherichia coli, approximately 40 genes are regulated by the LexA repressor. After a DNA damaging event, LexA degradation triggers SOS gene transcription, which is temporally separated into subsets of 'early', 'middle', and 'late' genes. Although this feature plays an important role in regulating the SOS response, both the range of this separation and its underlying mechanism are not experimentally defined. Here we show that, at low doses of DNA damage, the timing of promoter activities is not separated. Instead, timing differences only emerge at higher levels of DNA damage and increase as a function of DNA damage dose. To understand mechanism, we derived a series of synthetic SOS gene promoters which vary in LexA-operator binding kinetics, but are otherwise identical, and then studied their activity over a large dose-range of DNA damage. In distinction to established models based on rapid equilibrium assumptions, the data best fit a kinetic model of repressor occupancy at promoters, where the drop in cellular LexA levels associated with higher doses of DNA damage leads to non-equilibrium binding kinetics of LexA at operators. Operators with slow LexA binding kinetics achieve their minimal occupancy state at later times than operators with fast binding kinetics, resulting in a time separation of peak promoter activity between genes. These data provide insight into this remarkable feature of the SOS pathway by demonstrating how a single transcription factor can be employed to control the relative timing of each gene's transcription as a function of stimulus dose.

  14. A Possible Link between Supra-Second Open-Ended Timing Sensitivity and Obsessive-Compulsive Tendencies. (United States)

    Gilaie-Dotan, Sharon; Ashkenazi, Hamutal; Dar, Reuven


    One of the main characteristics of obsessive-compulsive disorder (OCD) is the persistent feeling of uncertainty, affecting many domains of actions and feelings. It was recently hypothesized that OCD uncertainty is related to attenuated access to internal states. As supra-second timing is associated with bodily and interoceptive awareness, we examined whether supra-second timing would be associated with OC tendencies. We measured supra-second (~9 s) and sub-second (~450 ms) timing along with control non-temporal perceptual tasks in a group of 60 university students. Supra-second timing was measured either with fixed criterion tasks requiring to temporally discriminate between two predefined fixed interval durations (9 vs. 9.9 s), or with an open-ended task requiring to discriminate between 9 s and longer intervals which were of varying durations that were not a priori known to the participants. The open-ended task employed an adaptive Bayesian procedure that efficiently estimated the duration difference required to discriminate 9 s from longer intervals. We also assessed symptoms of OCD, depression, and anxiety. Open-ended supra-second temporal sensitivity was correlated with OC tendencies, as predicted (even after controlling for depression and anxiety), whereas the other tasks were not. Higher OC tendencies were associated with lower timing sensitivity to 9 s intervals such that participants with higher OC tendency scores required longer interval differences to discriminate 9 s from longer intervals. While these results need to be substantiated in future research, they suggest that open-ended timing tasks, as those encountered in real-life (e.g., estimating how long it would take to complete a task), might be adversely affected in OCD.

  15. Linking the fractional derivative and the Lomnitz creep law to non-Newtonian time-varying viscosity


    Pandey, Vikash; Holm, Sverre


    Many of the most interesting complex media are non-Newtonian and exhibit time-dependent behavior of thixotropy and rheopecty. They may also have temporal responses described by power laws. The material behavior is represented by the relaxation modulus and the creep compliance. On the one hand, it is shown that in the special case of a Maxwell model characterized by a linearly time-varying viscosity, the medium's relaxation modulus is a power law which is similar to that of a fractional deriva...

  16. Retention of a 24-hour time memory in Syrian hamsters carrying the 20-hour short circadian period mutation in casein kinase-1ε (ck1εtau/tau). (United States)

    Cain, Sean W; Yoon, Jeena; Shrestha, Tenjin C; Ralph, Martin R


    Circadian rhythmic expression of conditioned place avoidance (CPA) was produced in Syrian hamsters homozygous for the circadian short period mutation, tau. In constant dim red light neither the 20 h endogenous period, nor a 20 h place conditioning schedule eliminated the 24 h modulation of CPA behavior described previously for wild type (wt) hamsters and other species. Tau mutants exhibited a 20 h rhythm superimposed on the 24 h modulation. The 20 h component was removed selectively with lesions of the suprachiasmatic nucleus. Wt animals conditioned on a 20 h schedule did not produce a 20 h rhythm, but still expressed the 24 h modulation. The results show that the context entrainable oscillator (CEO) underlying memory for the timing of an unconditioned stimulus, retains a period of about 24 h regardless of clock gene background (tau mutation) and/or the conditioning schedule (24 vs 20 h). Therefore the CEO responsible for time memory is distinct from the biological clock controlling activity; the underlying circadian molecular mechanisms may differ from the ubiquitous transcription-translation feedback oscillator; and time memory itself is not classically conditioned. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. Time-Dependent Variations in the Arctic’s Surface Albedo Feedback and the Link to Seasonality in Sea Ice

    NARCIS (Netherlands)

    Andry, Olivier; Bintanja, Richard; Hazeleger, Wilco


    The Arctic is warming 2 to 3 times faster than the global average. Arctic sea ice cover is very sensitive to this warming and has reached historic minima in late summer in recent years (e.g., 2007 and 2012). Considering that the Arctic Ocean is mainly ice covered and that the albedo of sea ice is

  18. Time Value of Money and Its Applications in Corporate Finance: A Technical Note on Linking Relationships between Formulas (United States)

    Chen, Jeng-Hong


    Time Value of Money (TVM) is the most important chapter in the basic corporate finance course. It is imperative to understand TVM formulas because they imply important TVM concepts. Students who really understand TVM concepts and formulas can learn better in chapters of TVM applications. This technical note intends to present more complete TVM…

  19. Linking granulation performance with residence time and granulation liquid distributions in twin-screw granulation: An experimental investigation

    DEFF Research Database (Denmark)

    Kumar, Ashish; Alakarjula, Maija; Vanhoorne, Valérie


    Twin-screw granulation is a promising wet granulation technique for the continuous manufacturing of pharmaceutical solid dosage forms. A twin screw granulator displays a short residence time. Thus, the solid-liquid mixing must be achieved quickly by appropriate arrangement of transport and kneading...

  20. Effects of linear and nonlinear time-delayed feedback on the noise-enhanced stability phenomenon in a periodically driven bistable system

    International Nuclear Information System (INIS)

    Jia, Zheng-Lin; Mei, Dong-Cheng


    We investigate numerically the effects of time delay on the phenomenon of noise-enhanced stability (NES) in a periodically modulated bistable system. Three types of time-delayed feedback, including linear delayed feedback, nonlinear delayed feedback and global delayed feedback, are considered. We find a non-monotonic behaviour of the mean first-passage time (MFPT) as a function of the delay time τ, with a maximum in the case of linear delayed feedback and with a minimum in the case of nonlinear delayed feedback. There are two peculiar values of τ around which the NES phenomenon is enhanced or weakened. For the case of global delayed feedback, the increase of τ always weakens the NES phenomenon. Moreover, we also show that the amplitude A and the frequency Ω of the periodic forcing play an opposite role in the NES phenomenon, i.e. the increase of A weakens the NES effect while the increase of Ω enhances it. These observations demonstrate that the time-delayed feedback can be used as a feasible control scheme for the NES phenomenon

  1. A Method for Exploring the Link between Urban Area Expansion over Time and the Opportunity for Crime in Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Mofza Algahtany


    Full Text Available Urban area expansion is one of the most critical types of worldwide change, and most urban areas are experiencing increased growth in population and infrastructure development. Urban change leads to many changes in the daily activities of people living within an affected area. Many studies have suggested that urbanization and crime are related. However, they focused particularly on land uses, types of land use, and urban forms, such as the physical features of neighbourhoods, roads, shopping centres, and bus stations. Understanding the correlation between urban area expansion and crime is very important for criminologists and urban planning decision-makers. In this study, we have used satellite images to measure urban expansion over a 10-year period and tested the correlations between these expansions and the number of criminal activities within these specific areas. The results show that there is a measurable relationship between urban expansion and criminal activities. Our findings support the crime opportunity theory as one possibility, which suggests that population density and crime are conceptually related. We found the correlations are stronger where there has been greater urban growth. Many other factors that may affect crime rate are not included in this paper, such as information on the spatial details of the population, city planning, economic considerations, the distance from the city centre, neighbourhood quality, and police numbers. However, this study will be of particular interest to those who aim to use remote sensing to study patterns of crime.

  2. High frequency dynamics of an isotropic Timoshenko periodic beam by the use of the Time-domain Spectral Finite Element Method (United States)

    Żak, A.; Krawczuk, M.; Palacz, M.; Doliński, Ł.; Waszkowiak, W.


    In this work results of numerical simulations and experimental measurements related to the high frequency dynamics of an aluminium Timoshenko periodic beam are presented. It was assumed by the authors that the source of beam structural periodicity comes from periodical alterations to its geometry due to the presence of appropriately arranged drill-holes. As a consequence of these alterations dynamic characteristics of the beam are changed revealing a set of frequency band gaps. The presence of the frequency band gaps can help in the design process of effective sound filters or sound barriers that can selectively attenuate propagating wave signals of certain frequency contents. In order to achieve this a combination of three numerical techniques were employed by the authors. They comprise the application of the Time-domain Spectral Finite Element Method in the case of analysis of finite and semi-infinite computational domains, damage modelling in the case of analysis of drill-hole influence, as well as the Bloch reduction in the case of analysis of periodic computational domains. As an experimental technique the Scanning Laser Doppler Vibrometry was chosen. A combined application of all these numerical and experimental techniques appears as new for this purpose and not reported in the literature available.

  3. The time since last menstrual period is important as a clinical predictor for non-steroidal aromatase inhibitor-related arthralgia. (United States)

    Kanematsu, Miyuki; Morimoto, Masami; Honda, Junko; Nagao, Taeko; Nakagawa, Misako; Takahashi, Masako; Tangoku, Akira; Sasa, Mitsunori


    The clinical predictors of aromatase inhibitor-related arthralgia (AIA), a drug-related adverse reaction of aromatase inhibitors (AIs), remain unclear. AIA was prospectively surveyed every 4 months in 328 postmenopausal breast cancer patients administered a non-steroidal AI (anastrozole). Various clinicopathological parameters were recorded and analyzed (chi-square test, Fisher's exact test and logistic regression analysis). The mean observation period was 39.9 months. AIA manifested in 114 patients (34.8%), with peaks of onset at 4 (33.7%) and 8 months (11.4%) after starting AI administration. Some cases manifested even after 13 months. AIA tended to occur in younger patients (incidences of 46.3%, 37.4% and 28.0% for ages of 65 years, respectively (p = 0.063)) and decreased significantly with the age at menarche (53.3%, 35.3% and 15.4% for 15 years, respectively (p = 0.036)). The incidences were 45.1%, 46.3 and 25.1% for the time since the last menstrual period (LMP) 10 years, being significantly lower at > 10 years (p time since LMP > 10-year group versus the time since LMP became shorter ( 10 years since LMP. When the time since LMP was short, the onset of AIA was significantly earlier after starting AI administration.

  4. The space - time - cube and the display of large movement data sets: the link between visualization strategies and cartographic design guidelines

    DEFF Research Database (Denmark)

    Kveladze, Irma; Kraak, Menno-Jan


    one should not only consider the nature of the data, but also the purpose of the particular phase of the workflow. To verify the above approach the visualization strategies and design guidelines are applied in a different use cases. The cases include: • The annotated space-time path A travel log...... is the Space-Time-cube (STC). The last decades the interest in this representation has increased considerable because of the technological opportunities. Despite the many domains where the STC is used, it is still unclear what the full possibilities and limitations of this graphic representation are. Its three...... consisting of a trajectory based on different modes of transport, with linked annotations. The challenge is to deal different scales and annotations. • The historical movement data The event ‘Napoleons march to Moscow’ contains fifteen space-time paths (STP) with attribute information. Challenge is to answer...

  5. Joint model-based clustering of nonlinear longitudinal trajectories and associated time-to-event data analysis, linked by latent class membership: with application to AIDS clinical studies. (United States)

    Huang, Yangxin; Lu, Xiaosun; Chen, Jiaqing; Liang, Juan; Zangmeister, Miriam


    Longitudinal and time-to-event data are often observed together. Finite mixture models are currently used to analyze nonlinear heterogeneous longitudinal data, which, by releasing the homogeneity restriction of nonlinear mixed-effects (NLME) models, can cluster individuals into one of the pre-specified classes with class membership probabilities. This clustering may have clinical significance, and be associated with clinically important time-to-event data. This article develops a joint modeling approach to a finite mixture of NLME models for longitudinal data and proportional hazard Cox model for time-to-event data, linked by individual latent class indicators, under a Bayesian framework. The proposed joint models and method are applied to a real AIDS clinical trial data set, followed by simulation studies to assess the performance of the proposed joint model and a naive two-step model, in which finite mixture model and Cox model are fitted separately.

  6. Comparison of Intraoperatively Built Custom Linked Seeds Versus Loose Seed Gun Applicator Technique Using Real-Time Intraoperative Planning for Permanent Prostate Brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Zauls, A. Jason; Ashenafi, Michael S. [Department of Radiation Oncology, Hollings Cancer Center, Medical University of South Carolina, Charleston, SC (United States); Onicescu, Georgiana [Department of Biostatistics and Epidemiology, Hollings Cancer Center, Medical University of South Carolina, Charleston, SC (United States); Clarke, Harry S. [Department of Urology, Hollings Cancer Center, Medical University of South Carolina, Charleston, SC (United States); Marshall, David T., E-mail: [Department of Radiation Oncology, Hollings Cancer Center, Medical University of South Carolina, Charleston, SC (United States)


    Purpose: To report our dosimetric results using a novel push-button seed delivery system that constructs custom links of seeds intraoperatively. Methods and Materials: From 2005 to 2007, 43 patients underwent implantation using a gun applicator (GA), and from 2007 to 2008, 48 patientsunderwent implantation with a novel technique allowing creation of intraoperatively built custom links of seeds (IBCL). Specific endpoint analyses were prostate D90% (pD90%), rV100% > 1.3 cc, and overall time under anesthesia. Results: Final analyses included 91 patients, 43 GA and 48 IBCL. Absolute change in pD90% ({Delta}pD90%) between intraoperative and postoperative plans was evaluated. Using GA method, the {Delta}pD90% was -8.1Gy and -12.8Gy for I-125 and Pd-103 implants, respectively. Similarly, the IBCL technique resulted in a {Delta}pD90% of -8.7Gy and -9.8Gy for I-125 and Pd-103 implants, respectively. No statistically significant difference in {Delta}pD90% was found comparing methods. The GA method had two intraoperative and 10 postoperative rV100% >1.3 cc. For IBCL, five intraoperative and eight postoperative plans had rV100% >1.3 cc. For GA, the mean time under anesthesia was 75 min and 87 min for Pd-103 and I-125 implants, respectively. For IBCL, the mean time was 86 and 98 min for Pd-103 and I-125. There was a statistical difference between the methods when comparing mean time under anesthesia. Conclusions: Dosimetrically relevant endpoints were equivalent between the two methods. Currently, time under anesthesia is longer using the IBCL technique but has decreased over time. IBCL is a straightforward brachytherapy technique that can be implemented into clinical practice as an alternative to gun applicators.

  7. An analysis of time series of the goods and services national accounts in the Czech Republic within the period of 1993– 2003

    Directory of Open Access Journals (Sweden)

    Božena Bodečková


    Full Text Available The paper presents results of a statistical analysis of time series obtained in studies on the absolute level, variability, dynamics and developmental trends of selected items of national accounts in the transformation period of the Czech national economy and its transition to a market economy. The volume of gross turnover of goods and services, gross value added, gross domestic product and imports of goods and services were explored a base of final expenditure on the one hand and the volume of final consumption expenditure, gross capital formation, gross national final expenditure and exports of goods and services as factors influencing the volume of total final expenditures on the other. Short-terms point extrapolations were calculated on the basis of applied models of developmental trends within the period 1993– 2003.

  8. Controlling periodic ripple microstructure formation on 4H-SiC crystal with three time-delayed femtosecond laser beams of different linear polarizations. (United States)

    He, Wanlin; Yang, Jianjun; Guo, Chunlei


    The control of laser-induced periodic ripple microstructures on 4H-SiC crystal surface is studied using temporally delayed collinear three femtosecond laser pulse trains linearly polarized in different directions. The ripple orientation appears to develop independent of the individual laser polarizations and exhibits non-monotonical change with variable time delays, whose variation tendency is also affected by the polarization intersection angles. Remarkably, the ripple period is observed to transfer from high- to low-spatial-frequency regions, accompanied by distinctly improved morphological uniformity and clearness. The results are satisfactorily interpreted based on a physical model of the surface wave excitation on a transient index metasurface, which is confirmed by further experiments. Our investigations indicate that transient noneqilibrium dynamics of the material surface provides an effective way to manipulate the laser-induced microstructures.

  9. Timing and Duration of Volcanism in the North Atlantic Igneous Province: Implications for Geodynamics and Links to the Iceland Hotspot

    DEFF Research Database (Denmark)

    Storey, M.; Duncan, R. A.; Tegner, Christian


    estimates of erupted magmas and their cumulates to calculate melt production rates for the early Tertiary flood basalts of East Greenland and the Faeroes Islands. The lavas lie at opposite ends of the Greenland-Iceland-Faeroes Ridge, the postulated Iceland hotspot track, and record volcanic activity leading...... of plate separation. The upper part of this crust comprises seismically imaged, seaward-dipping, subaerially erupted lavas. By  50 Ma, eruption rates had diminished drastically and volcanic activity had narrowed to a much restricted portion of the East Greenland margin, at the western end of the Greenland......We combine new and published 40Ar/39Ar age determinations from incremental heating experiments on whole rocks and mineral separates to assess the timing, duration and distribution of volcanic activity during construction of the North Atlantic Igneous Province. We use these ages together with volume...

  10. Retailer's optimal credit period and cycle time in a supply chain for deteriorating items with up-stream and down-stream trade credits (United States)

    Mahata, Gour Chandra


    In practice, the supplier often offers the retailers a trade credit period and the retailer in turn provides a trade credit period to her/his customer to stimulate sales and reduce inventory. From the retailer's perspective, granting trade credit not only increases sales and revenue but also increases opportunity cost (i.e., the capital opportunity loss during credit period) and default risk (i.e., the percentage that the customer will not be able to pay off his/her debt obligations). Hence, how to determine credit period is increasingly recognized as an important strategy to increase retailer's profitability. Also, the selling items such as fruits, fresh fishes, gasoline, photographic films, pharmaceuticals and volatile liquids deteriorate continuously due to evaporation, obsolescence and spoilage. In this paper, we propose an economic order quantity model for the retailer where (1) the supplier provides an up-stream trade credit and the retailer also offers a down-stream trade credit, (2) the retailer's down-stream trade credit to the buyer not only increases sales and revenue but also opportunity cost and default risk, and (3) the selling items are perishable. Under these conditions, we model the retailer's inventory system as a profit maximization problem to determine the retailer's optimal replenishment decisions under the supply chain management. We then show that the retailer's optimal credit period and cycle time not only exist but also are unique. We deduce some previously published results of other researchers as special cases. Finally, we use some numerical examples to illustrate the theoretical results.

  11. Bidirectional longitudinal relationship between leisure-time physical activity and psychotropic medication usage: A register linked follow-up study. (United States)

    Stubbs, Brendon; Vancampfort, Davy; Mänty, Minna; Svärd, Anna; Rahkonen, Ossi; Lahti, Jouni


    This study aimed to examine the bidirectional relationship between psychotropic medication use and changes in leisure-time physical activity (LTPA) among a population cohort study. Phase 1 data were collected by mail surveys in 2000-2002 among 40-60-year-old employees of the City of Helsinki, Finland, and phase 2 follow up survey was conducted in 2007. Based on self-report, the respondents were classified as inactive and active (≥14.75 MET-hours/week) at the phases 1 and 2. Hazard ratios (HR) were calculated for subsequent (2007-10) psychotropic medication purchasing according to changes in physical activity (phases 1-2). Odds ratios (OR) for physical inactivity at phase 2 were calculated according to the amount of psychotropic medication between phases 1-2. Overall, 5361 respondents were included (mean age 50 years, 80% women). Compared with the persistently active, the persistently inactive, those decreasing and adopting LTPA had an increased risk for psychotropic medication. Only the persistently inactive remained at increased risk for psychotropic medication use, following the adjustment for prior psychotropic medication use. Compared with those having no medication, the risk for physical inactivity increased as the psychotropic medication increased. Our data suggest that physical activity has an important role in maintaining wellbeing and reducing psychotropic medication usage. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  12. A unifying view of climate change in the Sahel linking intra-seasonal, interannual and longer time scales

    International Nuclear Information System (INIS)

    Giannini, A; Salack, S; Gaye, A T; Lodoun, T; Ali, A; Ndiaye, O


    We propose a re-interpretation of the oceanic influence on the climate of the African Sahel that is consistent across observations, 20th century simulations and 21st century projections, and that resolves the uncertainty in projections of precipitation change in this region: continued warming of the global tropical oceans increases the threshold for convection, potentially drying tropical land, but this ‘upped ante’ can be met if sufficient moisture is supplied in monsoon flow. In this framework, the reversal to warming of the subtropical North Atlantic, which is now out-pacing warming of the global tropical oceans, provides that moisture, and explains the partial recovery in precipitation since persistent drought in the 1970s and 1980s. We find this recovery to result from increases in daily rainfall intensity, rather than in frequency, most evidently so in Senegal, the westernmost among the three Sahelian countries analyzed. Continuation of these observed trends is consistent with projections for an overall wetter Sahel, but more variable precipitation on all time scales, from intra-seasonal to multi-decadal. (letter)

  13. Linking the Diffusion of Water in Compacted Clays at Two Different Time Scales: Tracer Through-Diffusion and QENS

    International Nuclear Information System (INIS)

    Juranyi, Fanni; Gonzalez Sanchez, Fatima; Gimmi, Thomas; Bestel, Martina; Van Loon, Luc; Diamond, Larryn W.


    Observable water diffusion processes in clays and their parameters depend on the spatial- and time-scale of the measurement. Comparing the diffusion coefficients of quasielastic neutron scattering and tracer through-diffusion, 'chemical' and 'geometrical' effects can be distinguished and quantified. Results for montmorillonite and illite in the Na- and Ca- form illustrate this very well. Swelling clays such as montmorillonite are especially interesting because of the interlayer water. This water is confined in form of few layers such that the diffusion occurs essentially in 2D. Furthermore the ratio of interlayer- and external- (macro-pore) water changes as a function of bulk dry density and degree of water saturation. Therefore it is of interest to describe the diffusion process using these parameters. Finally, the activation energy of the diffusion should be equal for both methods assuming that the geometrical factor does not depend on temperature. For the montmorillonites this was not the case, which might also indicate that the main processes on the two scales are different. We conclude that the geometrical factor and the electrostatic constraint can be determined from a comparison of the diffusion coefficients measured by the two different techniques: quasielastic neutron scattering and tracer through diffusion. Furthermore, activation energies obtained at the two scales are similar for clays having no interlayer water. For montmorillonite the activation energy values are different. Further investigations are required to clarify the reason. (authors)

  14. Comparison of surgical time and IOP spikes with two ophthalmic viscosurgical devices following Visian STAAR (ICL, V4c model insertion in the immediate postoperative period

    Directory of Open Access Journals (Sweden)

    Ganesh S


    Full Text Available Sri Ganesh, Sheetal BrarDepartment of Phaco and Refractive Surgeries, Nethradhama Superspeciality Eye Hospital, Bangalore, IndiaPurpose: To compare the effect of two ocular viscosurgical devices (OVDs on intraocular pressure (IOP and surgical time in immediate postoperative period after bilateral implantable collamer lens (using the V4c model implantation.Methods: A total of 20 eligible patients were randomized to receive 2% hydroxypropylmethylcellulose (HPMC in one eye and 1% hyaluronic acid in fellow eye. Time taken for complete removal of OVD and total surgical time were recorded. At the end of surgery, IOP was adjusted between 15 and 20 mmHg in both the eyes.Results: Mean time for complete OVD evacuation and total surgical time were significantly higher in the HPMC group (P=0.00. Four eyes in the HPMC group had IOP spike, requiring treatment. IOP values with noncontact tonometry at 1, 2, 4, 24, and 48 hours were not statistically significant (P>0.05 for both the groups.Conclusion: The study concluded that 1% hyaluronic acid significantly reduces total surgical time, and incidence of acute spikes may be lower compared to 2% HPMC when used for implantable collamer lens (V4c model.Keywords: OVD, hyaluronic acid, ICL, V4c, IOP spikes

  15. Concentration- and time-dependent genotoxicity profiles of isoprene monoepoxides and diepoxide, and the cross-linking potential of isoprene diepoxide in cells

    Directory of Open Access Journals (Sweden)

    Yan Li


    Full Text Available Isoprene, a possible carcinogen, is a petrochemical and a natural product being primarily produced by plants. It is biotransformed to 2-ethenyl-2-methyloxirane (IP-1,2-O and 2-(1-methylethenyloxirane (IP-3,4-O, both of which can be further metabolized to 2-methyl-2,2′-bioxirane (MBO. MBO is mutagenic, but IP-1,2-O and IP-3,4-O are not. While IP-1,2-O has been reported being genotoxic, the genotoxicity of IP-3,4-O and MBO, and the cross-linking potential of MBO have not been examined. In the present study, we used the comet assay to investigate the concentration- and time-dependent genotoxicity profiles of the three metabolites and the cross-linking potential of MBO in human hepatocyte L02 cells. For the incubation time of 1 h, all metabolites showed positive concentration-dependent profiles with a potency rank order of IP-3,4-O > MBO > IP-1,2-O. In human hepatocellular carcinoma (HepG2 and human leukemia (HL60 cells, IP-3,4-O was still more potent in inducing DNA breaks than MBO at high concentrations (>200 μM, although at low concentrations (≤200 μM IP-3,4-O exhibited slightly lower or similar potency to MBO. Interestingly, their time-dependent genotoxicity profiles (0.5–4 h in L02 cells were different from each other: IP-1,2-O and MBO (200 μM exhibited negative and positive profiles, respectively, with IP-3,4-O lying in between, namely, IP-3,4-O-caused DNA breaks did not change over the exposure time. Further experiments demonstrated that hydrolysis of IP-1,2-O contributed to the negative profile and MBO induced cross-links at high concentrations and long incubation times. Collectively, the results suggested that IP-3,4-O might play a significant role in the toxicity of isoprene.

  16. Linking Spatial Structure and Community-Level Biotic Interactions through Cooccurrence and Time Series Modeling of the Human Intestinal Microbiota. (United States)

    de Muinck, Eric J; Lundin, Knut E A; Trosvik, Pål


    The gastrointestinal (GI) microbiome is a densely populated ecosystem where dynamics are determined by interactions between microbial community members, as well as host factors. The spatial organization of this system is thought to be important in human health, yet this aspect of our resident microbiome is still poorly understood. In this study, we report significant spatial structure of the GI microbiota, and we identify general categories of spatial patterning in the distribution of microbial taxa along a healthy human GI tract. We further estimate the biotic interaction structure in the GI microbiota, both through time series and cooccurrence modeling of microbial community data derived from a large number of sequentially collected fecal samples. Comparison of these two approaches showed that species pairs involved in significant negative interactions had strong positive contemporaneous correlations and vice versa, while for species pairs without significant interactions, contemporaneous correlations were distributed around zero. We observed similar patterns when comparing these models to the spatial correlations between taxa identified in the adherent microbiota. This suggests that colocalization of microbial taxon pairs, and thus the spatial organization of the GI microbiota, is driven, at least in part, by direct or indirect biotic interactions. Thus, our study can provide a basis for an ecological interpretation of the biogeography of the human gut. IMPORTANCE The human gut microbiome is the subject of intense study due to its importance in health and disease. The majority of these studies have been based on the analysis of feces. However, little is known about how the microbial composition in fecal samples relates to the spatial distribution of microbial taxa along the gastrointestinal tract. By characterizing the microbial content both in intestinal tissue samples and in fecal samples obtained daily, we provide a conceptual framework for how the spatial

  17. Long-term exposure to mobile communication radiation: An analysis of time-variability of electric field level in GSM900 down-link channels

    International Nuclear Information System (INIS)

    Miclaus, S.; Bechet, P.; Gheorghevici, M.


    Interest for knowing long-term human exposure levels due to mobile communications has increased in the last years. It has been shown that short-term exposure assessment made under standard procedural restrictions is not reliable when it comes to conclusions on long-term exposure levels. The present work is the result of a several week analysis of time variability of electric field level inside traffic and control channels of the GSM900 mobile communication down-link band and it indicates that a temporal model to allow future predictions of exposure on the long run is obtainable. Collecting, processing and statistically analysing the data provide expression of the maximum and weighted field strengths and their evolution in time. Specific electromagnetic footprints of the channels have been extracted, differentiations between their characteristics have been emphasised and practical advice is provided, with the scope of contributing to the development of reliable procedures for long-term exposure assessment. (authors)

  18. Dynamic link: user's manual

    International Nuclear Information System (INIS)

    Harada, Hiroo; Asai, Kiyoshi; Kihara, Kazuhisa.


    The purpose of dynamic link facility is to link a load module dynamically only when it is used in execution time. The facility is very useful for development, execution and maintenance of a large scale computer program which is too big to be saved as one load module in main memory, or it is poor economy to save it due to many unused subroutines depending on an input. It is also useful for standardization and common utilization of programs. Standard usage of dynamic link facility of FACOM M-200 computer system, a software tool which analyzes the effect of dynamic link facility and application of dynamic link to nuclear codes are described. (author)

  19. High sensitive reflection type long period fiber grating biosensor for real time detection of thyroglobulin, a differentiated thyroid cancer biomarker: the Smart Health project (United States)

    Quero, G.; Severino, R.; Vaiano, P.; Consales, M.; Ruvo, M.; Sandomenico, A.; Borriello, A.; Giordano, M.; Zuppolini, S.; Diodato, L.; Cutolo, A.; Cusano, A.


    We report the development of a reflection-type long period fiber grating (LPG) biosensor able to perform the real time detection of thyroid cancer markers in the needle washout of fine-needle aspiration biopsy. A standard LPG is first transformed in a practical probe working in reflection mode, then it is coated by an atactic-polystyrene overlay in order to increase its surrounding refractive index sensitivity and to provide, at the same time, the desired interfacial properties for a stable bioreceptor immobilization. The results provide a clear demonstration of the effectiveness and sensitivity of the developed biosensing platform, allowing the in vitro detection of human Thyroglobulin at sub-nanomolar concentrations.

  20. The time since last menstrual period is important as a clinical predictor for non-steroidal aromatase inhibitor-related arthralgia

    International Nuclear Information System (INIS)

    Kanematsu, Miyuki; Morimoto, Masami; Honda, Junko; Nagao, Taeko; Nakagawa, Misako; Takahashi, Masako; Tangoku, Akira; Sasa, Mitsunori


    The clinical predictors of aromatase inhibitor-related arthralgia (AIA), a drug-related adverse reaction of aromatase inhibitors (AIs), remain unclear. AIA was prospectively surveyed every 4 months in 328 postmenopausal breast cancer patients administered a non-steroidal AI (anastrozole). Various clinicopathological parameters were recorded and analyzed (chi-square test, Fisher's exact test and logistic regression analysis). The mean observation period was 39.9 months. AIA manifested in 114 patients (34.8%), with peaks of onset at 4 (33.7%) and 8 months (11.4%) after starting AI administration. Some cases manifested even after 13 months. AIA tended to occur in younger patients (incidences of 46.3%, 37.4% and 28.0% for ages of < 55, 55-65 and > 65 years, respectively (p = 0.063)) and decreased significantly with the age at menarche (53.3%, 35.3% and 15.4% for < 12, 12-15 and > 15 years, respectively (p = 0.036)). The incidences were 45.1%, 46.3 and 25.1% for the time since the last menstrual period (LMP) < 5 years, 5-10 years and > 10 years, being significantly lower at > 10 years (p < 0.001). In logistic regression analysis, the AIA incidence was significantly lower in the time since LMP > 10-year group versus the < 5-year group (odds ratio 0.44, p = 0.002), but the age at menarche showed no association. AIA manifested significantly earlier (≤ 6 months) as the time since LMP became shorter (< 5 years). AIA tends to manifest early after starting AI, but some cases show delayed onset. The incidence was significantly lower in patients with a duration of > 10 years since LMP. When the time since LMP was short, the onset of AIA was significantly earlier after starting AI administration

  1. Measured winter and spring-time indoor temperatures in UK homes over the period 1969–2010: A review and synthesis

    International Nuclear Information System (INIS)

    Vadodaria, K.; Loveday, D.L.; Haines, V.


    This paper presents a review and synthesis of average winter and spring-time indoor temperatures in UK homes measured over the period 1969–2010. Analysis of measured temperatures in a sample of solid wall dwellings in the UK, conducted as part of the CALEBRE research project, is included. The review suggests that, for periods when occupation was likely, there has been little or no increase in winter and spring-time average living room temperatures over the last 40 years, with average recorded living room temperatures having been historically lower than the WHO-recommended value of 21 °C. Correspondingly, for periods of likely occupation, average bedroom temperatures appear to have increased. Compared with non-domestic buildings, there have been fewer investigations of domestic thermal comfort, either in the UK or elsewhere, and hence the paper also calls for further detailed investigations of domestic indoor temperatures during occupied hours together with thermal comfort evaluations in order to better understand domestic thermal environments. Based on suggestions from the limited range of studies available to date, living room temperatures may need to be maintained within the range 20–22 °C for thermal satisfaction, though this requires confirmation through further research. The study also emphasises that improving the energy efficiency of homes should be the primary means to effect any increases in indoor temperatures that are deemed essential. Considerations for future policy are discussed. - Highlights: • We review indoor temperatures measured in UK homes during 1960-2010. • We present analysis of temperature recorded by our study in 20 UK homes. • Little or no increase observed in living room temperatures for the last 40 years. • Occupied bedroom temperatures appear to have increased. • Living room temperatures have been historically lower than the WHO guidelines

  2. Optimality of cycle time and inventory decisions in a two echelon inventory system with exponential price dependent demand under credit period (United States)

    Krugon, Seelam; Nagaraju, Dega


    This work describes and proposes an two echelon inventory system under supply chain, where the manufacturer offers credit period to the retailer with exponential price dependent demand. The model is framed as demand is expressed as exponential function of retailer’s unit selling price. Mathematical model is framed to demonstrate the optimality of cycle time, retailer replenishment quantity, number of shipments, and total relevant cost of the supply chain. The major objective of the paper is to provide trade credit concept from the manufacturer to the retailer with exponential price dependent demand. The retailer would like to delay the payments of the manufacturer. At the first stage retailer and manufacturer expressions are expressed with the functions of ordering cost, carrying cost, transportation cost. In second stage combining of the manufacturer and retailer expressions are expressed. A MATLAB program is written to derive the optimality of cycle time, retailer replenishment quantity, number of shipments, and total relevant cost of the supply chain. From the optimality criteria derived managerial insights can be made. From the research findings, it is evident that the total cost of the supply chain is decreased with the increase in credit period under exponential price dependent demand. To analyse the influence of the model parameters, parametric analysis is also done by taking with help of numerical example.

  3. Gyrochronology relating star age to rotational period is derived from first principles through a novel time dual for thermodynamics, named lingerdynamics (United States)

    Feria, Erlan H.


    Gyrochronology estimates the age of a low-mass star from its rotational period, which is found from changes in brightness caused by dark star spots. First revealed as an insight in (Skumanich, A. 1972, The Astrophysical Journal. 171: 565) it allows astronomers to find true sun-like stars that may harbor life in its planets (Meibom, S. et. al., Nature. 517: 589-591). Here a simple expression for the age of a star is derived through a novel linger thermo theory (LTT) integrating thermodynamics with its revealed time-dual, named lingerdynamics. This expression relates the star age to the ratio of past and present rotational period metrics (RPM) of lingerdynamics. LTT has been used earlier to derive a simple expression for the finding of the entropy of spherical-homogeneous mediums (Feria, E. H. Nov. 19, 2016, Linger Thermo Theory, IEEE Int’l Conf. on Smart Cloud, 18 pages, DOI 10.1109/SmartCloud.2016.57, Colombia Univ., N.Y., N.Y. and Feria, E. H. June 7th 2017, AAS 340th Meeting). In LTT the lifespan of system operation τ is given by: τ = (2Π /3v3)G2M2 x RPM where G is the gravitational constant, Π is the pace of mass-energy retention in s/m3 units (e.g., for our current sun it is given by 5 billion ‘future’ years over its volume), and v is the perpetual radial speed about the point-mass M. Since in LTT a star is modeled as a point mass at the center of its spherical volume, its RPM is not the same as the measured rotational period of an actual star. For instance, for our sun its equator rotational period is approximately 25.34 days, while in lingerdynamics it is a fraction of a day, i.e., 0.116 days, where this value is derived from the RPM expression 2πrsun/(GMsun / rsun)1/2 where 2πrsun is the circumference of the sun, (GMsun/rsun)1/2 is the perpetual radial speed v for our point-mass modeled sun, and rsun and Msun are the sun radius and point-mass, respectively. However, using conservation of angular momentum arguments it is assumed that the ratio of

  4. Influence of internal and external boundary conditions on the decrement factor and time lag heat flux of building walls in steady periodic regime

    International Nuclear Information System (INIS)

    Mazzeo, D.; Oliveti, G.; Arcuri, N.


    Highlights: • Dynamic behaviour of building walls subjected to sinusoidal and actual loadings. • The joint action of more temperature and heat flux loadings has been considered. • Dynamic parameters were defined by the internal and external fluctuating heat flux. • Use of the Total Harmonic Distortion to determine the number of harmonics required. • Study of the influence of external and internal loadings on dynamic parameters. - Abstract: The dynamic behaviour of opaque components of the building envelope in steady periodic regime is investigated using parameters defined by the fluctuating heat flux that is transferred in the wall. The use of the heat flux allows for the joint action of the loadings that characterise both the outdoor environment and the indoor air-conditioned environment to be taken into account. The analysis was developed in sinusoidal conditions to determine the frequency response of the wall and in non-sinusoidal conditions to identify the actual dynamic behaviour of the wall. The use of non-dimensional periodic thermal transmittance is proposed for the sinusoidal analysis in order to evaluate the decrement factor and the time lag that the heat flux undergoes in crossing the wall as well as the efficiency of heat storage. In the presence of non-sinusoidal loadings, the identification of the dynamic behaviour of the wall is obtained using several dynamic parameters: the decrement factor in terms of energy, defined as the ratio between the energy in a semi-period entering and exiting the wall; the decrement factor and the time lag in terms of heat flux, considering the maximum peak and the minimum peak. These parameters allow for the identification of how the form of the heat flux trend crossing the wall is modified. The number of harmonics to be considered for an accurate representation of heat fluxes is determined by means of the introduction of the Total Harmonic Distortion (THD), which quantifies the distortion of a non

  5. Frequency of electrophoretic changes consistent with feline infectious peritonitis in two different time periods (2004-2009 vs 2013-2014). (United States)

    Stranieri, Angelica; Giordano, Alessia; Bo, Stefano; Braghiroli, Chiara; Paltrinieri, Saverio


    Objectives The aim of this study was to evaluate whether the frequency of electrophoretic changes in serum of cats with feline infectious peritonitis (FIP) changed in recent years vs past years. Methods Agarose gel electrophoresis (AGE) and capillary zone electrophoresis (CZE) from cats with FIP and healthy cats recorded in the periods 2004-2009 and 2013-2014 were retrospectively analysed. Relative and absolute values of each electrophoretic fraction were recorded and the number of cats showing single or combined electrophoretic changes consistent with FIP (hypoalbuminaemia, inverted albumin to globulin [A:G] ratio, increased total protein, total globulin, alpha [α] 2 -globulin and gamma [γ]-globulin concentration) were counted. Additionally, a visual analysis of electrophoretograms was also performed. Results for the two time periods were statistically compared. Results The details of 91 AGE procedures (41 from cats with FIP and 50 from healthy cats) and 45 CZE procedures (26 from cats with FIP and 19 from healthy cats) were obtained from the database. No significant differences between the two time periods were found both in FIP and in healthy cats analysed with CZE and in healthy cats analysed with AGE. Compared with 2004-2009, cats with FIP sampled in 2013-2014 with AGE showed a significantly lower concentration of total protein, γ-globulins and total globulins, and a significantly higher A:G ratio and percentage of albumin and α 2 -globulins. Using both AGE and CZE, in recent years the proportion of cats with high α2-globulins without gammopathy and the proportion of cats with gammopathy alone decreased. With a visual approach, the number of patterns considered as dubious increased in the second period with AGE (non-statistically significant). Conclusions and relevance The frequency of electrophoretic abnormalities in cats with FIP decreased in recent years, independently of the technique employed. Although the mechanism responsible for this change was

  6. Noise Reduction, Atmospheric Pressure Admittance Estimation and Long-Period Component Extraction in Time-Varying Gravity Signals Using Ensemble Empirical Mode Decomposition

    Directory of Open Access Journals (Sweden)

    Linsong Wang


    Full Text Available Time-varying gravity signals, with their nonlinear, non-stationary and multi-scale characteristics, record the physical responses of various geodynamic processes and consist of a blend of signals with various periods and amplitudes, corresponding to numerous phenomena. Superconducting gravimeter (SG records are processed in this study using a multi-scale analytical method and corrected for known effects to reduce noise, to study geodynamic phenomena using their gravimetric signatures. Continuous SG (GWR-C032 gravity and barometric data are decomposed into a series of intrinsic mode functions (IMFs using the ensemble empirical mode decomposition (EEMD method, which is proposed to alleviate some unresolved issues (the mode mixing problem and the end effect of the empirical mode decomposition (EMD. Further analysis of the variously scaled signals is based on a dyadic filter bank of the IMFs. The results indicate that removing the high-frequency IMFs can reduce the natural and man-made noise in the data, which are caused by electronic device noise, Earth background noise and the residual effects of pre-processing. The atmospheric admittances based on frequency changes are estimated from the gravity and the atmospheric pressure IMFs in various frequency bands. These time- and frequency-dependent admittance values can be used effectively to improve the atmospheric correction. Using the EEMD method as a filter, the long-period IMFs are extracted from the SG time-varying gravity signals spanning 7 years. The resulting gravity residuals are well correlated with the gravity effect caused by the _ polar motion after correcting for atmospheric effects.

  7. Self-determined motivation in physical education and its links to motivation for leisure-time physical activity, physical activity, and well-being in general. (United States)

    Bagøien, Tor Egil; Halvari, Hallgeir; Nesheim, Hallgeir


    The present study tested a trans-contextual model based on self-determination theory of the relations between motivation in physical education, motivation in leisure-time physical activity, physical activity, and psychological well-being. Participants were 329 Norwegian upper secondary school students (M age = 16.5 yr., SD = 0.7). Students' perceptions of autonomy-supportive teachers in physical education were expected to be positively associated with students' psychological needs satisfaction in physical education, which was expected to be positively related to autonomous motivation for physical education participation. In turn, autonomous motivation for physical education was expected to be positively associated with perceived competence and autonomous motivation for leisure-time physical activity, which both were expected to be positively associated with leisure-time physical activity and psychological well-being in general. Structural equation models and bootstrapping supported the hypotheses and the indirect links between variables. Sex differences indicate that more research is needed on how to motivate girls to be more physically active in leisure time.

  8. Periodicity and time trends in the prevalence of total births and conceptions with congenital malformations among Jews and Muslims in Israel, 1999-2006: a time series study of 823,966 births. (United States)

    Agay-Shay, Keren; Friger, Michael; Linn, Shai; Peled, Ammatzia; Amitai, Yona; Peretz, Chava


    BACKGROUND Congenital malformations (CMs) are a leading cause of infant disability. Geophysical patterns such as 2-year, yearly, half-year, 3-month, and lunar cycles regulate much of the temporal biology of all life on Earth and may affect birth and birth outcomes in humans. Therefore, the aim of this study was to evaluate and compare trends and periodicity in total births and CM conceptions in two Israeli populations. METHODS Poisson nonlinear models (polynomial) were applied to study and compare trends and geophysical periodicity cycles of weekly births and weekly prevalence rate of CM (CMPR), in a time-series design of conception date within and between Jews and Muslims. The population included all live births and stillbirths (n = 823,966) and CM (three anatomic systems, eight CM groups [n = 2193]) in Israel during 2000 to 2006. Data were obtained from the Ministry of Health. RESULTS We describe the trend and periodicity cycles for total birth conceptions. Of eight groups of CM, periodicity cycles were statistically significant in four CM groups for either Jews or Muslims. Lunar month and biennial periodicity cycles not previously investigated in the literature were found to be statistically significant. Biennial cycle was significant in total births (Jews and Muslims) and syndactyly (Muslims), whereas lunar month cycle was significant in total births (Muslims) and atresia of small intestine (Jews). CONCLUSION We encourage others to use the method we describe as an important tool to investigate the effects of different geophysical cycles on human health and pregnancy outcomes, especially CM, and to compare between populations. Copyright © 2012 Wiley Periodicals, Inc.

  9. Economic performance of lactating dairy cows submitted for first service timed artificial insemination after a voluntary waiting period of 60 or 88 days. (United States)

    Stangaferro, M L; Wijma, R; Masello, M; Thomas, Mark J; Giordano, J O


    The objective of this study was to evaluate the economic performance of dairy cows managed with a voluntary waiting period (VWP) of 60 or 88 d. A secondary objective was estimating variation in cash flow under different input pricing scenarios through stochastic Monte Carlo simulations. Lactating Holstein cows from 3 commercial farms were blocked by parity group and total milk yield in their previous lactation and then randomly assigned to a VWP of 60 (VWP60; n = 1,352) or 88 d (VWP88; n = 1,359). All cows received timed-artificial insemination (TAI) for first service after synchronization of ovulation with the Double-Ovsynch protocol. For second and greater services, cows received artificial insemination (AI) after detection of estrus or the Ovsynch protocol initiated 32 ± 3 d after AI. Two analyses were performed: (1) cash flow per cow for the calving interval of the experimental lactation and (2) cash flow per slot occupied by each cow enrolled in the experiment for an 18-mo period after calving in the experimental lactation. Extending the VWP from 60 to 88 d delayed time to pregnancy during lactation (~20 d) and increased the risk of leaving the herd for multiparous cows (hazard ratio = 1.21). As a result, a smaller proportion of multiparous cows calved again and had a subsequent lactation (-6%). The shift in time to pregnancy combined with the herd exit dynamics resulted in longer lactation length for primiparous (22 d) but not multiparous cows. Longer lactations led to greater milk income over feed cost and a tendency for greater cash flow during the experimental lactation for primiparous but not multiparous cows in the VWP88 group. On the other hand, profitability per slot for the 18-mo period was numerically greater ($68 slot/18 mo) for primiparous cows but numerically reduced (-$85 slot/18 mo) for multiparous cows in the VWP88 treatment. For primiparous cows most of the difference in cash flow was explained by replacement cost, whereas for multiparous

  10. Monitoring Metabolite Profiles of Cannabis sativa L. Trichomes during Flowering Period Using 1H NMR-Based Metabolomics and Real-Time PCR. (United States)

    Happyana, Nizar; Kayser, Oliver


    Cannabis sativa trichomes are glandular structures predominantly responsible for the biosynthesis of cannabinoids, the biologically active compounds unique to this plant. To the best of our knowledge, most metabolomic works on C. sativa that have been reported previously focused their investigations on the flowers and leaves of this plant. In this study, (1)H NMR-based metabolomics and real-time PCR analysis were applied for monitoring the metabolite profiles of C. sativa trichomes, variety Bediol, during the last 4 weeks of the flowering period. Partial least squares discriminant analysis models successfully classified metabolites of the trichomes based on the harvest time. Δ (9)-Tetrahydrocannabinolic acid (1) and cannabidiolic acid (2) constituted the vital differential components of the organic preparations, while asparagine, glutamine, fructose, and glucose proved to be their water-extracted counterparts. According to RT-PCR analysis, gene expression levels of olivetol synthase and olivetolic acid cyclase influenced the accumulation of cannabinoids in the Cannabis trichomes during the monitoring time. Moreover, quantitative (1)H NMR and RT-PCR analysis of the Cannabis trichomes suggested that the gene regulation of cannabinoid biosynthesis in the C. sativa variety Bediol is unique when compared with other C. sativa varieties. Georg Thieme Verlag KG Stuttgart · New York.

  11. Real-time monitoring and massive inversion of source parameters of very long period seismic signals: An application to Stromboli Volcano, Italy (United States)

    Auger, E.; D'Auria, L.; Martini, M.; Chouet, B.; Dawson, P.


    We present a comprehensive processing tool for the real-time analysis of the source mechanism of very long period (VLP) seismic data based on waveform inversions performed in the frequency domain for a point source. A search for the source providing the best-fitting solution is conducted over a three-dimensional grid of assumed source locations, in which the Green's functions associated with each point source are calculated by finite differences using the reciprocal relation between source and receiver. Tests performed on 62 nodes of a Linux cluster indicate that the waveform inversion and search for the best-fitting signal over 100,000 point sources require roughly 30 s of processing time for a 2-min-long record. The procedure is applied to post-processing of a data archive and to continuous automatic inversion of real-time data at Stromboli, providing insights into different modes of degassing at this volcano. Copyright 2006 by the American Geophysical Union.

  12. Operative Links

    DEFF Research Database (Denmark)

    Wistoft, Karen; Højlund, Holger


    educational goals, learning content, or value clarification. Health pedagogy is often a matter of retrospective rationalization rather than the starting point of planning. Health and risk behaviour approaches override health educational approaches. Conclusions: Operational links between health education......, health professionalism, and management strategies pose the foremost challenge. Operational links indicates cooperative levels that facilitate a creative and innovative effort across traditional professional boundaries. It is proposed that such links are supported by network structures, shared semantics...

  13. Evolution of periodicity in periodical cicadas. (United States)

    Ito, Hiromu; Kakishima, Satoshi; Uehara, Takashi; Morita, Satoru; Koyama, Takuya; Sota, Teiji; Cooley, John R; Yoshimura, Jin


    Periodical cicadas (Magicicada spp.) in the USA are famous for their unique prime-numbered life cycles of 13 and 17 years and their nearly perfectly synchronized mass emergences. Because almost all known species of cicada are non-periodical, periodicity is assumed to be a derived state. A leading hypothesis for the evolution of periodicity in Magicicada implicates the decline in average temperature during glacial periods. During the evolution of periodicity, the determinant of maturation in ancestral cicadas is hypothesized to have switched from size dependence to time (period) dependence. The selection for the prime-numbered cycles should have taken place only after the fixation of periodicity. Here, we build an individual-based model of cicadas under conditions of climatic cooling to explore the fixation of periodicity. In our model, under cold environments, extremely long juvenile stages lead to extremely low adult densities, limiting mating opportunities and favouring the evolution of synchronized emergence. Our results indicate that these changes, which were triggered by glacial cooling, could have led to the fixation of periodicity in the non-periodical ancestors.

  14. Cooperative effect of random and time-periodic coupling strength on synchronization transitions in one-way coupled neural system: mean field approach. (United States)

    Jiancheng, Shi; Min, Luo; Chusheng, Huang


    The cooperative effect of random coupling strength and time-periodic coupling strengh on synchronization transitions in one-way coupled neural system has been investigated by mean field approach. Results show that cooperative coupling strength (CCS) plays an active role for the enhancement of synchronization transitions. There exist an optimal frequency of CCS which makes the system display the best CCS-induced synchronization transitions, a critical frequency of CCS which can not further affect the CCS-induced synchronization transitions, and a critical amplitude of CCS which can not occur the CCS-induced synchronization transitions. Meanwhile, noise intensity plays a negative role for the CCS-induced synchronization transitions. Furthermore, it is found that the novel CCS amplitude-induced synchronization transitions and CCS frequency-induced synchronization transitions are found.


    Directory of Open Access Journals (Sweden)



    Full Text Available The maximum amounts of rainfall are usually characterized by high intensity, and their effects on the substrate are revealed, at slope level, by the deepening of the existing forms of torrential erosion and also by the formation of new ones, and by landslide processes. For the 1971-2000 period, for the weather stations in the hilly area of Cluj County: Cluj- Napoca, Dej, Huedin and Turda the highest values of rainfall amounts fallen in 24, 48 and 72 hours were analyzed and extracted, based on which the variation and the spatial and temporal distribution of the precipitation were analyzed. The annual probability of exceedance of maximum rainfall amounts fallen in short time intervals (24, 48 and 72 hours, based on thresholds and class values was determined, using climatological practices and the Hyfran program facilities.

  16. Optical pulse multiplication and temporal coding using true time delay achieved by long-period fiber gratings in dispersion compensating fiber. (United States)

    Eom, Tae Joong; Kim, Sun-Jong; Kim, Tae-Young; Park, Chang-Soo; Lee, Byeong


    We present an optical pulse multiplication and a temporal coding method for OCDMA systems. The true time delay among the pulses was obtained by utilizing the difference in the propagation speeds of the core and the co-propagating cladding modes coupled by long-period fiber gratings. By cascadin gratings we could get an equally spaced 40 GHz pulse train from a 10 GHz train. Various coding and decoding of a pulse train were possible by controlling the separations among the gratings. The dispersion compensating fiber having an inner cladding structure enabled to have the gratings that were not sensitive to the polymer jacket of the fiber and allowed shortening the device length.

  17. Is there a link between per capita alcohol consumption and youth drinking? A time-series analysis for Sweden in 1972-2012. (United States)

    Norström, Thor; Raninen, Jonas


    To estimate the relationship between per capita alcohol consumption and youth drinking in Sweden during the last 40 years and to estimate the relationship between female and male youth drinking during the 40-year study period. Per capita alcohol consumption was proxied by official sales data, supplemented by data on unrecorded consumption. Youth consumption was measured by a question on heavy episodic drinking (HED) included in an annual school survey of alcohol and drug habits among Swedish 9th -grade students (15-16 years of age). The annual samples comprise approximately 5000 individuals (with roughly equal numbers of boys and girls) with response rates in the range 80-93%. The study spans the period 1972-2012. Autoregressive integrated moving average (ARIMA) time-series analysis was used to estimate the relation between per-capita alcohol consumption and youth drinking. Ocular inspection of the time-series data suggested a stronger synchronization between the two series in the early period, before the mid-1990s, than in the later period, indicating a structural shift in the relation at issue. We therefore conducted period specific time-series analyses with 1995 as the year of division. There was a statistically significant relation between per capita alcohol consumption and HED among youth for 1972-94. A 1% increase in per capita alcohol consumption was associated with an increase in HED of 1.52% (P = 0.008). The estimate for 1995-2012 (0.12) was well below statistical significance (P = 0.580). The estimated elasticity of the association between boys' and girls' HED during 1972-94 was close to unity (0.98, P < 0.001), suggesting proportional changes in boys' and girls' drinking. When controlling for per capita consumption, the association was halved (to 0.55) but still significant in table 3 (P = 0.045). Adult and youth drinking in Sweden were synchronized closely during the two last decades of the 20th century, but youth drinking developed an

  18. Skill of real-time operational forecasts with the APCC multi-model ensemble prediction system during the period 2008-2015 (United States)

    Min, Young-Mi; Kryjov, Vladimir N.; Oh, Sang Myeong; Lee, Hyun-Ju


    This paper assesses the real-time 1-month lead forecasts of 3-month (seasonal) mean temperature and precipitation on a monthly basis issued by the Asia-Pacific Economic Cooperation Climate Center (APCC) for 2008-2015 (8 years, 96 forecasts). It shows the current level of the APCC operational multi-model prediction system performance. The skill of the APCC forecasts strongly depends on seasons and regions that it is higher for the tropics and boreal winter than for the extratropics and boreal summer due to direct effects and remote teleconnections from boundary forcings. There is a negative relationship between the forecast skill and its interseasonal variability for both variables and the forecast skill for precipitation is more seasonally and regionally dependent than that for temperature. The APCC operational probabilistic forecasts during this period show a cold bias (underforecasting of above-normal temperature and overforecasting of below-normal temperature) underestimating a long-term warming trend. A wet bias is evident for precipitation, particularly in the extratropical regions. The skill of both temperature and precipitation forecasts strongly depends upon the ENSO strength. Particularly, the highest forecast skill noted in 2015/2016 boreal winter is associated with the strong forcing of an extreme El Nino event. Meanwhile, the relatively low skill is associated with the transition and/or continuous ENSO-neutral phases of 2012-2014. As a result the skill of real-time forecast for boreal winter season is higher than that of hindcast. However, on average, the level of forecast skill during the period 2008-2015 is similar to that of hindcast.

  19. Dynamics of Mixed Dipterocarps Forests in Wanariset Semboja, East Kalimantan after Three Times of Forest Fires within the Periods of 1980-2003

    Directory of Open Access Journals (Sweden)



    Full Text Available A plot of 150x700 m2 was established in a mixed dipterocarps of Wanariset Semboja, East Kalimantan during the periods of 1979-1981. The forest was dominated by Eusideroxylon zwageri (Lauraceae, Dipterocarpus cornutus (Dipterocarpaceae, Pholidocarpus majadum (Arecaceae, and Diospyros borneensis (Ebenaceae. Since the plot establishment, the forests then had experienced three times of forest fires, those were in 1982-1983, 1994-1995 and 1997-1998. The present paper reports the results of re-measurement of some 150x110 m2 parts of the plot in August 2003, about 23 years after plot establishment. Micro topographically, the studied plot was relatively undulating in higher parts and relatively flat in the lower parts of the plot, while the differences between lowest sub-plot and higher sub-plot of the re-measured plot was 26 m. Forest floor of the lower parts of the plot were humid to wet during rainy season and still humid during dry season. Almost all of the trees within lower parts of the plot were escaped from these three times of forest fires; hence these sub-plots were dominated by the trees of primary species that enumerated in 1980. Those sub-plots in the higher parts were burnt during the past forest fires indicated by the charcoal of standing trees and remaining felling logs in the forest floor. These burnt sub-plots were dominated by pioneer or secondary tree species, such as: Mallotus spp., Macaranga spp., Ficus spp. and Vernonia arborea. Local distribution of some indicator species (such as primary tree species: Pholidocarpus majadum, Diospyros spp., Eusideroxylon zwageri and species of Dipterocarpaceae; pioneer or secondary tree species Vernonia arborea, Macaranga spp., Mallotus spp., Ficus uncinulata, Piper aduncum, Peronema canescens within the plot were figured. Mortality, recruitment and growth rate during the period of 1980-2003 were also discussed.

  20. Cardiovascular risk factors determined via the Internet in 2 periods of time: 2004–2009 and 2010–2015 in Poland

    Directory of Open Access Journals (Sweden)

    Bartosz G. Trzeciak


    Full Text Available Objectives: Web information systems may serve as a diagnostic tool for the Internet users and they also support the epidemiological work of doctors and health care providers. As part of this study, a system has been created for detecting and calculating cardiovascular risk. The aim of this study has been the comparison of cardiovascular risk factors and calculated fatal cardiovascular risk in 2 periods of time: 2004–2009 and 2010–2015 in Poland, as determined via the Internet. Material and Methods: The “Ryzyko program” (“Risk program” is available on the website of the Medical University of Gdańsk. To assess the cardiovascular death risk in a 10-year period, the algorithm of the SCORE (Systematic Coronary Risk Evaluation project was used and 30 402 results of the algorithm have been analyzed. Results: Over 30 402 webpage visitors entered the required data and received the outcome. More than 78% of the Internet users who had entered the data, received a recommendation for medical check-up. Significant differences between the data collected in 2004– 2009 and 2010–2015 were noticed. Hypercholesterolemia prevalence (67.3% vs. 70.8%; p < 0.001, mean total cholesterol concentration in blood (5.60±1.65 mml/l vs. 5.66±1.35 mml/l; p < 0.001, prevalence of hypertension (36.6% vs. 35.3%; p = 0.039, mean systolic blood pressure (131.5±20.3 mm Hg vs. 132.6±18.0 mm Hg; p < 0.001, prevalence of declared smoking (30.7% vs. 26.5%; p < 0.001, declared diabetes mellitus (DM (6.4% vs. 9.7%; p < 0.001, and declared coronary artery disease (CAD (7.2% vs. 14.1%; p < 0.001, respectively. Conclusions: The prevalence of cardiovascular risk factors has changed during the observed period of time. Online automatic gathering of new data by “Ryzyko program” provides up-to-date observations. Int J Occup Med Environ Health 2017;30(3:499–510

  1. Problem Periods (United States)

    ... ovary syndrome. Read our information on PCOS for teens , and see your doctor if you think you may have PCOS. Major weight loss. Girls who have anorexia will often stop having periods. When to see ...

  2. Is it time to rebalance the case mix? A portfolio analysis of direct catheterization laboratory costs over a 5-year period. (United States)

    Plehn, Gunnar; Butz, Thomas; Maagh, Petra; Oernek, Ahmet; Meissner, Axel; Plehn, Natalie


    Cardiac catheterization laboratories (CLL) have continued to function as profit centers for hospitals. Due to a high percentage of material and labor costs, they are natural targets for process improvement. Our study applied a contribution margin (CBM) concept to evaluate costs and cost dynamics over a 5-year period. We retrospectively analyzed all procedures performed at a tertiary heart center between 2007 and 2011. Total variable costs, including labor time, material, and maintenance-expenses, were allocated at a global as well as a procedural level. CBM and CBM ratios were calculated by integration of individual DRG revenues. Annual case volume increased from 1288 to 1545. In parallel, overall profitability improved as indicated by a 2% increase in CBM ratio and a higher CBM generated per hour of CLL working time (4325 vs. 5892 €, p analysis of CLL costs and cost dynamics. From a health service providers view, its range of application includes global profitability analysis, portfolio evaluation, and a detailed cost analysis of specific service lines. From a healthcare payers perspective, it may help to monitor hospital activities and to provide a solid data basis in cases where inappropriate developments are suspected. The calculation principle is simple which may increase user acceptance and thus the motivation of team members.

  3. Inter-Hemispheric Coupling During Recent North Polar Summer Periods as Predicted by MaCWAVE/MIDAS Rocket Data and Traced by TIMED/SABER Measurements (United States)

    Goldberg, Richard A.; Feofilov, Artem G.; Kutepov, Alexander A.; Pesnell W. Dean; Schmidlin, Francis J.


    In July, 2002, the MaCWAVE-MIDAS Rocket Program was launched from Andoya Rocket Range (ARR) in Norway. Data from these flights demonstrated that the polar summer mesosphere during this period was unusual, at least above ARR. Theoretical studies have since been published that imply that the abnormal characteristics of this polar summer were generated by dynamical processes occurring in the southern polar winter hemisphere. We have used data from the SABER instrument aboard the NASA Thermosphere Ionosphere Mesosphere Energetics and Dynamics (TIMED) Satellite to study these characteristics and compare them with the features observed in the ensuing eight years. For background, the TIMED Satellite was launched on December 7,2001 to study the dynamics and energy of the mesosphere and lower thermosphere. The SABER instrument is a limb scanning infrared radiometer designed to measure temperature of the region as well as a large number of minor constituents. In this study, we review the MaCWAVE rocket results. Next, we investigate the temperature characteristics of the polar mesosphere as a function of spatial and temporal considerations. We have used the most recent SABER dataset (1.07). Weekly averages are used to make comparisons between the winter and summer hemispheres. Furthermore, the data analysis agrees with recent theoretical studies showing that this behavior is a result of anomalous dynamical events in the southern hemisphere. The findings discussed here clearly show the value of scientific rocket flights used in a discovery mode.

  4. An overview of techniques for linking high-dimensional molecular data to time-to-event endpoints by risk prediction models. (United States)

    Binder, Harald; Porzelius, Christine; Schumacher, Martin


    Analysis of molecular data promises identification of biomarkers for improving prognostic models, thus potentially enabling better patient management. For identifying such biomarkers, risk prediction models can be employed that link high-dimensional molecular covariate data to a clinical endpoint. In low-dimensional settings, a multitude of statistical techniques already exists for building such models, e.g. allowing for variable selection or for quantifying the added value of a new biomarker. We provide an overview of techniques for regularized estimation that transfer this toward high-dimensional settings, with a focus on models for time-to-event endpoints. Techniques for incorporating specific covariate structure are discussed, as well as techniques for dealing with more complex endpoints. Employing gene expression data from patients with diffuse large B-cell lymphoma, some typical modeling issues from low-dimensional settings are illustrated in a high-dimensional application. First, the performance of classical stepwise regression is compared to stage-wise regression, as implemented by a component-wise likelihood-based boosting approach. A second issues arises, when artificially transforming the response into a binary variable. The effects of the resulting loss of efficiency and potential bias in a high-dimensional setting are illustrated, and a link to competing risks models is provided. Finally, we discuss conditions for adequately quantifying the added value of high-dimensional gene expression measurements, both at the stage of model fitting and when performing evaluation. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Birthweight and placental weight; do changes in culture media used for IVF matter? Comparisons with spontaneous pregnancies in the corresponding time periods. (United States)

    Eskild, Anne; Monkerud, Lars; Tanbo, Tom


    Have changes in culture media used for IVF resulted in changes in offspring birthweight or placental weight that differed from the trends in offspring from spontaneous conceptions during the corresponding time periods? Changes in culture media used for IVF were associated with significant differences in offspring birthweight and in placental weight to birthweight ratio when compared with the trend in offspring from spontaneous conceptions during the time periods. The effect of culture media used for IVF on offspring birthweight has varied between studies. There is a large variation in birthweight between newborns, and birthweight may vary across populations and over time. Such variations may therefore have influenced previous results. We included all singleton births from IVF at one treatment center in Norway during the years 1999-2011(n = 2435) and all singleton births from spontaneous conceptions in Norway during the same years (n = 698 359). Three different media were used for embryo culture; Medicult Universal IVF (1999 through 2007, n = 1584), Medicult ISM1 (2008 until 20 September 2009, n = 402) and Vitrolife G-1 PLUS (21 September 2009 through 2011, n = 449). We estimated mean birthweight and placental weight in IVF pregnancies by culture media. We also estimated mean weights in IVF and in spontaneous pregnancies by year of birth. Thereafter, we studied whether the changes in mean weights in IVF pregnancies differed from the changes in weight in spontaneous pregnancies in the periods corresponding to culture media changes by applying a grouped difference-in-difference analysis. Adjustments were made for parity, maternal age and gestational age at birth. In singleton offspring from IVF the mean birthweight was 3447.6 g with Medicult Universal, 3351.7 g with Medicult ISM1 and 3441.4 g with Vitrolife G-1 PLUS (P ISM1 (P = 0.16) and increased with 79.9 g by the change from Medicult ISM1 to Vitrolife G-1 PLUS (P = 0.01) when compared with changes in offspring

  6. Linking open vocabularies

    CERN Document Server

    Greifender, Elke; Seadle, Michael


    Linked Data (LD), Linked Open Data (LOD) and generating a web of data, present the new knowledge sharing frontier. In a philosophical context, LD is an evolving environment that reflects humankinds' desire to understand the world by drawing on the latest technologies and capabilities of the time. LD, while seemingly a new phenomenon did not emerge overnight; rather it represents the natural progression by which knowledge structures are developed, used, and shared. Linked Open Vocabularies is a significant trajectory of LD. Linked Open Vocabularies targets vocabularies that have traditionally b

  7. Validation of two novel electronic devices to time-link transcutaneous electrical nerve stimulation and pain report in patients with chronic back pain. (United States)

    Pallett, Edward J; Rentowl, Patricia; Watson, Paul J


    The analgesic effectiveness of transcutaneous electrical nerve stimulation (TENS) is uncertain. Negative findings, interpreted as ineffectiveness, might be due to poor methodological quality. Monitoring is necessary to differentiate between ineffectiveness and low implementation fidelity. Electronic data-logging devices, "TLOG" and "TSCORE," were developed to monitor and time-link TENS and pain report. TLOG records the time and duration of TENS use and output parameters; TSCORE records time-stamped pain scores. The purpose was to determine the accuracy, reliability, and acceptability of the devices. Forty-two outpatients with chronic back pain consented to use TENS daily for 2 weeks. Treatment times and durations were recorded in paper diaries and compared with TLOG data. Using TSCORE, patients reported pain before, during, and after TENS. Pain scores, reported using TSCORE or paper numerical rating scale at the beginning and end of 2 study visits, were compared using Bland-Altman methodology. The mean (SD) difference between paper and TSCORE pain scores was -0.05 (0.81). Limits of agreement (mean difference ± 1.96 SD) were -1.65 to 1.55. Test-retest reliabilities of paper and TSCORE were comparable: Paper mean (SD) difference was -0.33 (0.66), limits of agreement were -1.62 to 0.96; TSCORE mean (SD) difference was -0.10 (0.31), limits were -0.7 to 0.5. TLOG recorded TENS use accurately and worked reliably for 2 weeks in 84% of cases. An overall 79% of participants preferred TSCORE to paper numerical rating scale. TLOG and TSCORE are accurate, reliable, and acceptable devices for monitoring TENS implementation fidelity and pain outcome, with potential for improving TENS research methodology and clinical application.

  8. Green-roof as a solution to solve stormwater management issues? Assessment on a long time period at the parcel scale

    Directory of Open Access Journals (Sweden)

    P.-A. Versini


    Full Text Available Experimental green-roof rainfall–runoff observations have shown a positive impact on stormwater management at the building scale; with a decrease in the peak discharge and a decrease in runoff volume. This efficiency of green-roofs varies from one rainfall event to another depending on precipitation characteristics and substrate antecedent conditions. Due to this variability, currently, green-roofs are rarely officially used as a regulation tool to manage stormwater. Indeed, regulation rules governing the connection to the stormwater network are usually based on absolute threshold values that always have to be respected: maximum areal flow-rate or minimum retention volume for example. In this context, the aim of this study is to illustrate how a green-roof could represent an alternative to solve stormwater management issues, if the regulation rules were further based on statistics. For this purpose, a modelling scheme has been established at the parcel scale to simulate the hydrological response of several roof configurations: impervious, strictly regulated (in terms of areal flow-rate or retention volume, and covered by different types of green-roof matter. Simulations were carried out on a long precipitation time period (23 years that included a large and heterogeneous set of hydrometeorological conditions. Results obtained for the different roof configurations were compared. Based on the return period of the rainfall event, the probability to respect some regulation rules (defined from real situations was assessed. They illustrate that green-roofs reduce stormwater runoff compared to an impervious roof surface and can guarantee the respect of the regulation rules in most of the cases. Moreover, their implementation can appear more realistic than that of other infrastructures strictly complying with regulations and demanding significant storage capacity.

  9. The Mucosal Immune Function Is Not Compromised during a Period of High-Intensity Interval Training. Is It Time to Reconsider an Old Assumption? (United States)

    Born, Dennis-Peter; Zinner, Christoph; Sperlich, Billy


    Purpose: The aim of the study was to evaluate the mucosal immune function and circadian variation of salivary cortisol, Immunoglobin-A (sIgA) secretion rate and mood during a period of high-intensity interval training (HIIT) compared to long-slow distance training (LSD). Methods: Recreational male runners (n = 28) completed nine sessions of either HIIT or LSD within 3 weeks. The HIIT involved 4 × 4 min of running at 90–95% of maximum heart rate interspersed with 3 min of active recovery while the LSD comprised of continuous running at 70–75% of maximum heart rate for 60–80 min. The psycho-immunological stress-response was investigated with a full daily profile of salivary cortisol and immunoglobin-A (sIgA) secretion rate along with the mood state on a baseline day, the first and last day of training and at follow-up 4 days after the last day of training. Before and after the training period, each athlete's running performance and peak oxygen uptake (V·O2peak) was determined with an incremental exercise test. Results: The HIIT resulted in a longer time-to-exhaustion (P = 0.02) and increased V·O2peak compared to LSD (P = 0.01). The circadian variation of sIgA secretion rate showed highest values in the morning immediately after waking up followed by a decrease throughout the day in both groups (P HIIT, the wake-up response of sIgA secretion rate was higher on the last day of training (P HIIT and LSD (P HIIT indicates no compromised mucosal immune function compared to LSD and shows the functional adaptation of the mucosal immune system in response to the increased stress and training load of nine sessions of HIIT. PMID:28744226

  10. Studies on time of death estimation in the early post mortem period -- application of a method based on eyeball temperature measurement to human bodies. (United States)

    Kaliszan, Michał


    This paper presents a verification of the thermodynamic model allowing an estimation of the time of death (TOD) by calculating the post mortem interval (PMI) based on a single eyeball temperature measurement at the death scene. The study was performed on 30 cases with known PMI, ranging from 1h 35min to 5h 15min, using pin probes connected to a high precision electronic thermometer (Dostmann-electronic). The measured eye temperatures ranged from 20.2 to 33.1°C. Rectal temperature was measured at the same time and ranged from 32.8 to 37.4°C. Ambient temperatures which ranged from -1 to 24°C, environmental conditions (still air to light wind) and the amount of hair on the head were also recorded every time. PMI was calculated using a formula based on Newton's law of cooling, previously derived and successfully tested in comprehensive studies on pigs and a few human cases. Thanks to both the significantly faster post mortem decrease of eye temperature and a residual or nonexistent plateau effect in the eye, as well as practically no influence of body mass, TOD in the human death cases could be estimated with good accuracy. The highest TOD estimation error during the post mortem intervals up to around 5h was 1h 16min, 1h 14min and 1h 03min, respectively in three cases among 30, while for the remaining 27 cases it was not more than 47min. The mean error for all 30 cases was ±31min. All that indicates that the proposed method is of quite good precision in the early post mortem period, with an accuracy of ±1h for a 95% confidence interval. On the basis of the presented method, TOD can be also calculated at the death scene with the use of a proposed portable electronic device (TOD-meter). Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  11. Analysis of a lin-42/period Null Allele Implicates All Three Isoforms in Regulation of Caenorhabditis elegans Molting and Developmental Timing

    Directory of Open Access Journals (Sweden)

    Theresa L. B. Edelman


    Full Text Available The Caenorhabditis elegans heterochronic gene pathway regulates the relative timing of events during postembryonic development. lin-42, the worm homolog of the circadian clock gene, period, is a critical element of this pathway. lin-42 function has been defined by a set of hypomorphic alleles that cause precocious phenotypes, in which later developmental events, such as the terminal differentiation of hypodermal cells, occur too early. A subset of alleles also reveals a significant role for lin-42 in molting; larval stages are lengthened and ecdysis often fails in these mutant animals. lin-42 is a complex locus, encoding overlapping and nonoverlapping isoforms. Although existing alleles that affect subsets of isoforms have illuminated important and distinct roles for this gene in developmental timing, molting, and the decision to enter the alternative dauer state, it is essential to have a null allele to understand all of the roles of lin-42 and its individual isoforms. To remedy this problem and discover the null phenotype, we engineered an allele that deletes the entire lin-42 protein-coding region. lin-42 null mutants are homozygously viable, but have more severe phenotypes than observed in previously characterized hypomorphic alleles. We also provide additional evidence for this conclusion by using the null allele as a base for reintroducing different isoforms, showing that each isoform can provide heterochronic and molting pathway activities. Transcript levels of the nonoverlapping isoforms appear to be under coordinate temporal regulation, despite being driven by independent promoters. The lin-42 null allele will continue to be an important tool for dissecting the functions of lin-42 in molting and developmental timing.

  12. Time trends in exposure of cattle to bovine spongiform encephalopathy and cohort effect in France and Italy: value of the classical Age-Period-Cohort approach. (United States)

    Sala, Carole; Ru, Giuseppe


    The Age-Period-Cohort (APC) analysis is routinely used for time trend analysis of cancer incidence or mortality rates, but in veterinary epidemiology, there are still only a few examples of this application. APC models were recently used to model the French epidemic assuming that the time trend for BSE was mainly due to a cohort effect in relation to the control measures that may have modified the BSE exposure of cohorts over time. We used a categorical APC analysis which did not require any functional form for the effect of the variables, and examined second differences to estimate the variation of the BSE trend. We also reanalysed the French epidemic and performed a simultaneous analysis of Italian data using more appropriate birth cohort categories for comparison. We used data from the exhaustive surveillance carried out in France and Italy between 2001 and 2007, and comparatively described the trend of the epidemic in both countries. At the end, the shape and irregularities of the trends were discussed in light of the main control measures adopted to control the disease. In Italy a decrease in the epidemic became apparent from 1996, following the application of rendering standards for the processing of specific risk material (SRM). For the French epidemic, the pattern of second differences in the birth cohorts confirmed the beginning of the decrease from 1995, just after the implementation of the meat and bone meal (MBM) ban for all ruminants (1994). The APC analysis proved to be highly suitable for the study of the trend in BSE epidemics and was helpful in understanding the effects of management and control of the disease. Additionally, such an approach may help in the implementation of changes in BSE regulations.

  13. A sense of urgency: Evaluating the link between clinical trial development time and the accrual performance of cancer therapy evaluation program (NCI-CTEP) sponsored studies. (United States)

    Cheng, Steven K; Dietrich, Mary S; Dilts, David M


    Postactivation barriers to oncology clinical trial accruals are well documented; however, potential barriers prior to trial opening are not. We investigate one such barrier: trial development time. National Cancer Institute Cancer Therapy Evaluation Program (CTEP)-sponsored trials for all therapeutic, nonpediatric phase I, I/II, II, and III studies activated between 2000 and 2004 were investigated for an 8-year period (n = 419). Successful trials were those achieving 100% of minimum accrual goal. Time to open a study was the calendar time from initial CTEP submission to trial activation. Multivariate logistic regression analysis was used to calculate unadjusted and adjusted odds ratios (OR), controlling for study phase and size of expected accruals. Among the CTEP-approved oncology trials, 37.9% (n = 221) failed to attain the minimum accrual goals, with 70.8% (n = 14) of phase III trials resulting in poor accrual. A total of 16,474 patients (42.5% of accruals) accrued to those studies were unable to achieve the projected minimum accrual goal. Trials requiring less than 12 months of development were significantly more likely to achieve accrual goals (OR, 2.15; 95% confidence interval, 1.29-3.57, P = 0.003) than trials with the median development times of 12 to 18 months. Trials requiring a development time of greater than 24 months were significantly less likely to achieve accrual goals (OR, 0.40; 95% confidence interval, 0.20-0.78; P = 0.011) than trials with the median development time. A large percentage of oncology clinical trials do not achieve minimum projected accruals. Trial development time appears to be one important predictor of the likelihood of successfully achieving the minimum accrual goals. ©2010 AACR.

  14. Animal evolution and atmospheric pO2: is there a link between gradual animal adaptation to terrain elevation due to Ural orogeny and survival of subsequent hypoxic periods? (United States)

    Kurbel, Sven


    Considering evolution of terrestrial animals as something happening only on flat continental plains seems wrong. Many mountains have arisen and disappeared over the geologic time scale, so in all periods some areas of high altitude existed, with reduced oxygen pressure (pO2) and increased aridity. During orogeny, animal species of the raising terrain can slowly adapt to reduced oxygen levels.This review proposes that animal evolution was often driven by atmospheric oxygen availability. Transitions of insect ancestors and amphibians out of water are here interpreted as events forced by the lack of oxygen in shallow and warm water during Devonian. Hyperoxia during early Carboniferous allowed giant insects to be predators of lowlands, forcing small amphibians to move to higher terrains, unsuitable to large insects due to reduced pO2. In arid mountainous habitats, ascended animals evolved in early reptiles with more efficient lungs and improved circulation. Animals with alveolar lungs became the mammalian ancestors, while those with respiratory duct lungs developed in archosaurs. In this interpretation, limb precursors of wings and pneumatised bones might have been adaptations for moving on steep slopes.Ural mountains have risen to an estimated height of 3000 m between 318 and 251 Mya. The earliest archosaurs have been found on the European Ural side, estimated 275 Myr old. It is proposed that Ural orogeny slowly elevated several highland habitats within the modern Ural region to heights above 2500 m. Since this process took near 60 Myr, animals in these habitats fully to adapted to hypoxia.The protracted P-Tr hypoxic extinction event killed many aquatic and terrestrial animals. Devastated lowland areas were repopulated by mammaliaformes that came down from mountainous areas. Archosaurs were better adapted to very low pO2, so they were forced to descend to the sea level later when the lack of oxygen became severe. During the Triassic period, when the relative content

  15. Understanding the link between meteorology and speciated abundance of bioaerosols in an urban environment using colocated flow cytometry and real-time autofluorescence measurements (United States)

    Negron Marty, Arnaldo; DeLeon-Rodriguez, Natasha; Waters, Samantha; Ziemba, Luke; Anderson, Bruce; Bergin, Michael; Konstantinidis, Kostas; Nenes, Athanasios


    The abundance and speciation of primary biological atmospheric particles (PBAP) has been of great interest due to their potential impact on human health, cloud formation and contribution to atmospheric nutrient deposition [1, 2]. During this study state-of-the-art sampling techniques and protocols have been developed and combined with the speciation of PBAP by flow cytometry (FCM). An effective FCM protocol has been developed to identify and quantify speciated bioaerosols populations. In addition, a Wideband Integrated Bioaerosol Sensor (WIBS) has been used to understand the temporal variability of the PBAP, by measuring the autofluorescence of the atmospheric particles [3]. The techniques developed here have been applied to understand the PBAP variability and abundance in downtown Atlanta under different meteorological conditions. FCM results show the presence of a low nucleic acid (LNA) and a high nucleic acid (HNA) content subpopulation. The contribution of each subpopulation to the total biological atmospheric particles (TBAP) varies depending on the predominant meteorological conditions. Results suggest the HNA subpopulation, named fungal spores, dominates the composition of the TBAP during humid and warm days after rain events. However, during dry episodes the HNA subpopulation is diminished and the LNA subpopulation dominates the composition of the TBAP in downtown Atlanta. WIBS size distribution shifts between dry periods and humid and warm periods agreed well with the LNA and HNA subpopulations behavior. Our finding suggests Atlanta average PBAP concentration is around 1-8 x 104 part. /m3during Spring, where WIBS represents the lower bound and FCM the upper bound of the quantification. Additional experiments performed with different types of pollen, fungi and bacteria were used to better understand the scattering and fluorescence properties of them under different growing phases. References: [1] Morris, C. E., F. Conen, J. Alex Huffman, V. Phillips, U

  16. Early language development in children with profound hearing loss fitted with a device at a young age: part I--the time period taken to acquire first words and first word combinations. (United States)

    Nott, Pauline; Cowan, Robert; Brown, P Margaret; Wigglesworth, Gillian


    Increasing numbers of infants and young children are now presenting to implantation centers and early intervention programs as the impact of universal newborn hearing screening programs is felt worldwide. Although results of a number of studies have highlighted the benefit of early identification and early fitting of hearing devices, there is relatively little research on the impact of early fitting of these devices on first language milestones. The aim of this study was to investigate the early spoken language milestones of young children with hearing loss (HL) from two perspectives: first, the acquisition of the first lexicon (i.e., the first 100 words) and second, the emergence of the first word combinations. Two groups of participants, one comprising 24 participants with profound HL and a second comprising 16 participants with normal hearing, were compared. Twenty-three participants in the HL group were fitted with a cochlear implant and one with bilateral hearing aids. All of these were "switched-on" or fitted before 30 months of age and half at words and any word combinations produced while reaching this single-word target. Acquisition of single words was compared by using the time period (in days) taken to reach several single-word targets (e.g., 50 words, 100 words) from the date of production of the first word. The emergence of word combinations was analyzed from two perspectives: first, the time (in days) from the date of production of the first word to the emergence of the first word combinations and second, the size of the single-word lexicon when word combinations emerged. The normal-hearing group required a significantly shorter time period to acquire the first 50 (mean words than the HL group. Although both groups demonstrated acceleration in lexical acquisition, the hearing group took significantly fewer days to reach the second 50 words relative to the first 50 words than did the HL group. Finally, the hearing group produced word combinations

  17. Shear bond strength of composite to deep dentin after treatment with two different collagen cross-linking agents at varying time intervals. (United States)

    Srinivasulu, S; Vidhya, S; Sujatha, M; Mahalaxmi, S


    This in vitro study evaluated the shear bond strength of composite resin to deep dentin using a total etch adhesive after treatment with two collagen cross-linking agents at varying time intervals. Thirty freshly extracted human maxillary central incisors were sectioned longitudinally into equal mesial and distal halves (n=60). The proximal deep dentin was exposed, maintaining a remaining dentin thickness (RDT) of approximately 1 mm. The specimens were randomly divided into three groups based on the surface treatment of dentin prior to bonding as follows: group I (n=12, control): no prior dentin surface treatment; group II (n=24): dentin surface pretreated with 10% sodium ascorbate; and group III (n=24): dentin surface pretreated with 6.5% proanthocyanidin. Groups II and III were further subdivided into two subgroups of 12 specimens each, based on the pretreatment time of five minutes (subgroup A) and 10 minutes (subgroup B). Shear bond strength of the specimens was tested with a universal testing machine, and the data were statistically analyzed. Significantly higher shear bond strength to deep dentin was observed in teeth treated with 10% sodium ascorbate (group II) and 6.5% proanthocyanidin (group III) compared to the control group (group I). Among the collagen cross-linkers used, specimens treated with proanthocyanidin showed significantly higher shear bond strength values than those treated with sodium ascorbate. No significant difference was observed between the five-minute and 10-minute pretreatment times in groups II and III. It can be concluded that dentin surface pretreatment with both 10% sodium ascorbate and 6.5% proanthocyanidin resulted in significant improvement in bond strength of resin composite to deep dentin.

  18. Impact of Harvesting Time and Length of Cold Storage Period On Physiological and Quality Traits of Four Quince Genotypes (Cydonia Oblonga Mill.

    Directory of Open Access Journals (Sweden)

    Tatari Maryam


    Full Text Available The investigation was conducted to determine the best harvesting time and the storage period of some quince cultivars and promising genotypes from the collection of quince germplasm in the Horticultural Research Station of Isfahan, Iran. For this study, fruits of ‘Vidoja’ and ‘Isfahan’ cultivars as well as promising genotypes PH2 and NB4 were harvested on 6, 14 and 21 October 2015 and 2016 and then stored at 0 ± 1 °C with 90 ± 5% R.H. for five months. Weight loss, firmness, total soluble solids (TSS, titrable acids (TA, taste index, pectin, total phenols, and percent of decay and surface browning of fruits were measured immediately after harvest and one-month intervals after storage in a factorial experiment based on a completely randomized design with three replications and 10 fruits per each replication. The results showed that ‘Isfahan’ cultivar had the highest TSS (18.83%, total phenols and weight loss. The least weight loss was observed in the ‘Vidoja’ cultivar. NB4 genotype showed the least taste index and pectin, while the most pectin and firmness was related to PH2 genotype. Generally, the delay in harvesting and prolongation of storage led to increasing of TSS and weight loss and declining of firmness and phenols, TA, and pectins. Until the third month of storage, there was no surface browning. Browning symptoms were observed from the fourth month of storage and increased in the fifth month up to 1.72%. Generally, the best harvesting time for ‘Vidoja’ was 185 days and for the rest of the genotypes, it was 193 days after full bloom. Fruit storage for four months in cold is advisable for these cultivars and genotypes.

  19. The analysis in real time, during the pre-commissioning period, of the overall plant control system of the CANDU NPP unit

    International Nuclear Information System (INIS)

    Tapu, C.; Irimia, M.


    The physical processes in the CANDU NPP are controlled by a computer system which, based on the associated package of programmes, performs both the monitoring function at the level of the operational area, and the digital regulation function of the technological systems within the NPP. For an optimal operation of the NPP, in dynamic as well as in stationary regime, the correlation of the direct digital control of the technological systems is very important for the NPP's overall digital control system. Taking into account the fact that during the pre-commissioning period of a CANDU unit it is necessary to test in dynamic regime the performance of the overall digital control function of the NPP, a system of verification and testing in real time was developed, by connecting a micro simulator of the physical process in the NPP to the actual computer system of the unit. The paper presents the methods and techniques used, as well as the results of the tests for various operational modes, which highlight the functioning of the digital control system of the CANDU NPP unit. (Author)

  20. Effect of time period after boric acid injection on {sup 10}B absorption in different regions of adult male rat's brain

    Energy Technology Data Exchange (ETDEWEB)

    Baghban Khojasteh, Nasrin, E-mail: [Nuclear Engineering Department, Science and Research Branch, Islamic Azad University, Poonak Sq. PO Box 14515-775, Tehran (Iran, Islamic Republic of); Pazirandeh, Ali [Nuclear Engineering Department, Science and Research Branch, Islamic Azad University, Poonak Sq. PO Box 14515-775, Tehran (Iran, Islamic Republic of); Jameie, Behnam [Nuclear Engineering Department, Science and Research Branch, Islamic Azad University, Poonak Sq. PO Box 14515-775, Tehran (Iran, Islamic Republic of); Laboratory of Basic Science and Neuroscience, Basic Science Dept, Faculty of Allied Medicine, Cellular and Molecular Research Center, Tehran University of Medical Science, Pardis-e-Hemmat,Tehran (Iran, Islamic Republic of); Goodarzi, Samereh [Nuclear Engineering Department, Science and Research Branch, Islamic Azad University, Poonak Sq. PO Box 14515-775, Tehran (Iran, Islamic Republic of)


    Distribution of {sup 10}B in different regions of rat normal brain was studied. Two groups were chosen as control and trial. Trial group received 2 ml of neutral boron compound. 2, 4 and 6 h after the injection brain removed, coronal sections of forebrain, midbrain and hindbrain were sandwiched between two pieces of polycarbonate. Autoradiography plots of {sup 10}B distribution showed significant differences in three regions with the highest {sup 10}B concentration in the forebrain during 4 h after injection. - Highlights: Black-Right-Pointing-Pointer Normal tissue tolerance is very important in BNCT. Black-Right-Pointing-Pointer This study has been done to determine {sup 10}B distribution in three anatomical regions of rat normal brain. Black-Right-Pointing-Pointer These specific regions of brain have not been studied in previous BNCT projects. Black-Right-Pointing-Pointer We found significant differences in {sup 10}B distribution between these three regions. Black-Right-Pointing-Pointer In different time periods after neutral boron compound injection, there has been a significant difference in boron absorption.