WorldWideScience

Sample records for positive exponent family

  1. First-passage exponents of multiple random walks

    International Nuclear Information System (INIS)

    Ben-Naim, E; Krapivsky, P L

    2010-01-01

    We investigate first-passage statistics of an ensemble of N noninteracting random walks on a line. Starting from a configuration in which all particles are located in the positive half-line, we study S n (t), the probability that the nth rightmost particle remains in the positive half-line up to time t. This quantity decays algebraically, S n (t)∼t -β n , in the long-time limit. Interestingly, there is a family of nontrivial first-passage exponents, β 1 2 N-1 ; the only exception is the two-particle case where β 1 = 1/3. In the N → ∞ limit, however, the exponents attain a scaling form, β n (N) → β(z) with z=(n-N/2)/√N. We also demonstrate that the smallest exponent decays exponentially with N. We deduce these results from first-passage kinetics of a random walk in an N-dimensional cone and confirm them using numerical simulations. Additionally, we investigate the family of exponents that characterizes leadership statistics of multiple random walks and find that in this case, the cone provides an excellent approximation.

  2. Bayesian Estimation of the Logistic Positive Exponent IRT Model

    Science.gov (United States)

    Bolfarine, Heleno; Bazan, Jorge Luis

    2010-01-01

    A Bayesian inference approach using Markov Chain Monte Carlo (MCMC) is developed for the logistic positive exponent (LPE) model proposed by Samejima and for a new skewed Logistic Item Response Theory (IRT) model, named Reflection LPE model. Both models lead to asymmetric item characteristic curves (ICC) and can be appropriate because a symmetric…

  3. Hyperchaos of four state autonomous system with three positive Lyapunov exponents

    International Nuclear Information System (INIS)

    Ge Zhengming; Yang, C-H.

    2009-01-01

    This Letter gives the results of numerical simulations of Quantum Cellular Neural Network (Quantum-CNN) autonomous system with four state variables. Three positive Lyapunov exponents confirm hyperchaotic nature of its dynamics

  4. Lyapunov Exponents

    CERN Document Server

    Crauel, Hans; Eckmann, Jean-Pierre

    1991-01-01

    Since the predecessor to this volume (LNM 1186, Eds. L. Arnold, V. Wihstutz)appeared in 1986, significant progress has been made in the theory and applications of Lyapunov exponents - one of the key concepts of dynamical systems - and in particular, pronounced shifts towards nonlinear and infinite-dimensional systems and engineering applications are observable. This volume opens with an introductory survey article (Arnold/Crauel) followed by 26 original (fully refereed) research papers, some of which have in part survey character. From the Contents: L. Arnold, H. Crauel: Random Dynamical Systems.- I.Ya. Goldscheid: Lyapunov exponents and asymptotic behaviour of the product of random matrices.- Y. Peres: Analytic dependence of Lyapunov exponents on transition probabilities.- O. Knill: The upper Lyapunov exponent of Sl (2, R) cocycles:Discontinuity and the problem of positivity.- Yu.D. Latushkin, A.M. Stepin: Linear skew-product flows and semigroups of weighted composition operators.- P. Baxendale: Invariant me...

  5. A Hyperchaotic Attractor with Multiple Positive Lyapunov Exponents

    International Nuclear Information System (INIS)

    Guo-Si, Hu

    2009-01-01

    There are many hyperchaotic systems, but few systems can generate hyperchaotic attractors with more than three PLEs (positive Lyapunov exponents). A new hyperchaotic system, constructed by adding an approximate time-delay state feedback to a five-dimensional hyperchaotic system, is presented. With the increasing number of phase-shift units used in this system, the number of PLEs also steadily increases. Hyperchaotic attractors with 25 PLEs can be generated by this system with 32 phase-shift units. The sum of the PLEs will reach the maximum value when 23 phase-shift units are used. A simple electronic circuit, consisting of 16 operational amplifiers and two analogy multipliers, is presented for confirming hyperchaos of order 5, i.e., with 5 PLEs

  6. Critical behavior of the Lyapunov exponent in type-III intermittency

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez-Llamoza, O. [Departamento de Fisica, FACYT, Universidad de Carabobo, Valencia (Venezuela); Centro de Fisica Fundamental, Grupo de Caos y Sistemas Complejos, Universidad de Los Andes, Merida 5251, Merida (Venezuela)], E-mail: llamoza@ula.ve; Cosenza, M.G. [Centro de Fisica Fundamental, Grupo de Caos y Sistemas Complejos, Universidad de Los Andes, Merida 5251, Merida (Venezuela); Ponce, G.A. [Departamento de Fisica, Universidad Nacional Autonoma de Honduras (Honduras); Departamento de Ciencias Naturales, Universidad Pedagogica Nacional Francisco Morazan, Tegucigalpa (Honduras)

    2008-04-15

    The critical behavior of the Lyapunov exponent near the transition to robust chaos via type-III intermittency is determined for a family of one-dimensional singular maps. Critical boundaries separating the region of robust chaos from the region where stable fixed points exist are calculated on the parameter space of the system. A critical exponent {beta} expressing the scaling of the Lyapunov exponent is calculated along the critical curve corresponding to the type-III intermittent transition to chaos. It is found that {beta} varies on the interval 0 {<=} {beta} < 1/2 as a function of the order of the singularity of the map. This contrasts with earlier predictions for the scaling behavior of the Lyapunov exponent in type-III intermittency. The variation of the critical exponent {beta} implies a continuous change in the nature of the transition to chaos via type-III intermittency, from a second-order, continuous transition to a first-order, discontinuous transition.

  7. Critical behavior of the Lyapunov exponent in type-III intermittency

    International Nuclear Information System (INIS)

    Alvarez-Llamoza, O.; Cosenza, M.G.; Ponce, G.A.

    2008-01-01

    The critical behavior of the Lyapunov exponent near the transition to robust chaos via type-III intermittency is determined for a family of one-dimensional singular maps. Critical boundaries separating the region of robust chaos from the region where stable fixed points exist are calculated on the parameter space of the system. A critical exponent β expressing the scaling of the Lyapunov exponent is calculated along the critical curve corresponding to the type-III intermittent transition to chaos. It is found that β varies on the interval 0 ≤ β < 1/2 as a function of the order of the singularity of the map. This contrasts with earlier predictions for the scaling behavior of the Lyapunov exponent in type-III intermittency. The variation of the critical exponent β implies a continuous change in the nature of the transition to chaos via type-III intermittency, from a second-order, continuous transition to a first-order, discontinuous transition

  8. Designing Hyperchaotic Cat Maps With Any Desired Number of Positive Lyapunov Exponents.

    Science.gov (United States)

    Hua, Zhongyun; Yi, Shuang; Zhou, Yicong; Li, Chengqing; Wu, Yue

    2018-02-01

    Generating chaotic maps with expected dynamics of users is a challenging topic. Utilizing the inherent relation between the Lyapunov exponents (LEs) of the Cat map and its associated Cat matrix, this paper proposes a simple but efficient method to construct an -dimensional ( -D) hyperchaotic Cat map (HCM) with any desired number of positive LEs. The method first generates two basic -D Cat matrices iteratively and then constructs the final -D Cat matrix by performing similarity transformation on one basic -D Cat matrix by the other. Given any number of positive LEs, it can generate an -D HCM with desired hyperchaotic complexity. Two illustrative examples of -D HCMs were constructed to show the effectiveness of the proposed method, and to verify the inherent relation between the LEs and Cat matrix. Theoretical analysis proves that the parameter space of the generated HCM is very large. Performance evaluations show that, compared with existing methods, the proposed method can construct -D HCMs with lower computation complexity and their outputs demonstrate strong randomness and complex ergodicity.

  9. Variation of Zipf's exponent in one hundred live languages: A study of the Holy Bible translations

    Science.gov (United States)

    Mehri, Ali; Jamaati, Maryam

    2017-08-01

    Zipf's law, as a power-law regularity, confirms long-range correlations between the elements in natural and artificial systems. In this article, this law is evaluated for one hundred live languages. We calculate Zipf's exponent for translations of the holy Bible to several languages, for this purpose. The results show that, the average of Zipf's exponent in studied texts is slightly above unity. All studied languages in some families have Zipf's exponent lower/higher than unity. It seems that geographical distribution impresses the communication between speakers of different languages in a language family, and affect similarity between their Zipf's exponent. The Bible has unique concept regardless of its language, but the discrepancy in grammatical rules and syntactic regularities in applying stop words to make sentences and imply a certain concept, lead to difference in Zipf's exponent for various languages.

  10. The Evolution of the Exponent of Zipf's Law in Language Ontogeny

    Science.gov (United States)

    Baixeries, Jaume; Elvevåg, Brita; Ferrer-i-Cancho, Ramon

    2013-01-01

    It is well-known that word frequencies arrange themselves according to Zipf's law. However, little is known about the dependency of the parameters of the law and the complexity of a communication system. Many models of the evolution of language assume that the exponent of the law remains constant as the complexity of a communication systems increases. Using longitudinal studies of child language, we analysed the word rank distribution for the speech of children and adults participating in conversations. The adults typically included family members (e.g., parents) or the investigators conducting the research. Our analysis of the evolution of Zipf's law yields two main unexpected results. First, in children the exponent of the law tends to decrease over time while this tendency is weaker in adults, thus suggesting this is not a mere mirror effect of adult speech. Second, although the exponent of the law is more stable in adults, their exponents fall below 1 which is the typical value of the exponent assumed in both children and adults. Our analysis also shows a tendency of the mean length of utterances (MLU), a simple estimate of syntactic complexity, to increase as the exponent decreases. The parallel evolution of the exponent and a simple indicator of syntactic complexity (MLU) supports the hypothesis that the exponent of Zipf's law and linguistic complexity are inter-related. The assumption that Zipf's law for word ranks is a power-law with a constant exponent of one in both adults and children needs to be revised. PMID:23516390

  11. Lyapunov exponent for aging process in induction motor

    Science.gov (United States)

    Bayram, Duygu; Ünnü, Sezen Yıdırım; Şeker, Serhat

    2012-09-01

    Nonlinear systems like electrical circuits and systems, mechanics, optics and even incidents in nature may pass through various bifurcations and steady states like equilibrium point, periodic, quasi-periodic, chaotic states. Although chaotic phenomena are widely observed in physical systems, it can not be predicted because of the nature of the system. On the other hand, it is known that, chaos is strictly dependent on initial conditions of the system [1-3]. There are several methods in order to define the chaos. Phase portraits, Poincaré maps, Lyapunov Exponents are the most common techniques. Lyapunov Exponents are the theoretical indicator of the chaos, named after the Russian mathematician Aleksandr Lyapunov (1857-1918). Lyapunov Exponents stand for the average exponential divergence or convergence of nearby system states, meaning estimating the quantitive measure of the chaotic attractor. Negative numbers of the exponents stand for a stable system whereas zero stands for quasi-periodic systems. On the other hand, at least if one of the exponents is positive, this situation is an indicator of the chaos. For estimating the exponents, the system should be modeled by differential equation but even in that case mathematical calculation of Lyapunov Exponents are not very practical and evaluation of these values requires a long signal duration [4-7]. For experimental data sets, it is not always possible to acquire the differential equations. There are several different methods in literature for determining the Lyapunov Exponents of the system [4, 5]. Induction motors are the most important tools for many industrial processes because they are cheap, robust, efficient and reliable. In order to have healthy processes in industrial applications, the conditions of the machines should be monitored and the different working conditions should be addressed correctly. To the best of our knowledge, researches related to Lyapunov exponents and electrical motors are mostly

  12. Full spectrum of Lyapunov exponents in gauge field theories

    International Nuclear Information System (INIS)

    Biro, T.S.; Markum, H.; Pullirsch, R.

    2003-01-01

    Full text: Results are presented for the full spectrum of Lyapunov exponents of the compact U(1) gauge system in classical field theory. Instead of the determination of the largest Lyapunov exponent by the rescaling method we now use the monodromy matrix approach. The Lyapunov spectrum L i is expressed in terms of the eigenvalues Λ i of the monodromy matrix M. In the confinement phase the eigenvalues lie on either the real or on the imaginary axes. This is a nice illustration of a strange attractor of a chaotic system. Positive Lyapunov exponents eject the trajectories from oscillating orbits provided by the imaginary eigenvalues. Negative Lyapunov exponents attract the trajectories keeping them confined in the basin. Latest studies concern the time (in)dependence of the monodromy matrix. Further, we show that monopoles are created and annihilated in pairs as a function of real time in access to a fixed average monopole number. (author)

  13. Finite-time braiding exponents

    Science.gov (United States)

    Budišić, Marko; Thiffeault, Jean-Luc

    2015-08-01

    Topological entropy of a dynamical system is an upper bound for the sum of positive Lyapunov exponents; in practice, it is strongly indicative of the presence of mixing in a subset of the domain. Topological entropy can be computed by partition methods, by estimating the maximal growth rate of material lines or other material elements, or by counting the unstable periodic orbits of the flow. All these methods require detailed knowledge of the velocity field that is not always available, for example, when ocean flows are measured using a small number of floating sensors. We propose an alternative calculation, applicable to two-dimensional flows, that uses only a sparse set of flow trajectories as its input. To represent the sparse set of trajectories, we use braids, algebraic objects that record how trajectories exchange positions with respect to a projection axis. Material curves advected by the flow are represented as simplified loop coordinates. The exponential rate at which a braid stretches loops over a finite time interval is the Finite-Time Braiding Exponent (FTBE). We study FTBEs through numerical simulations of the Aref Blinking Vortex flow, as a representative of a general class of flows having a single invariant component with positive topological entropy. The FTBEs approach the value of the topological entropy from below as the length and number of trajectories is increased; we conjecture that this result holds for a general class of ergodic, mixing systems. Furthermore, FTBEs are computed robustly with respect to the numerical time step, details of braid representation, and choice of initial conditions. We find that, in the class of systems we describe, trajectories can be re-used to form different braids, which greatly reduces the amount of data needed to assess the complexity of the flow.

  14. Fermat's Last Theorem for Factional and Irrational Exponents

    Science.gov (United States)

    Morgan, Frank

    2010-01-01

    Fermat's Last Theorem says that for integers n greater than 2, there are no solutions to x[superscript n] + y[superscript n] = z[superscript n] among positive integers. What about rational exponents? Irrational n? Negative n? See what an undergraduate senior seminar discovered.

  15. Inverted rank distributions: Macroscopic statistics, universality classes, and critical exponents

    Science.gov (United States)

    Eliazar, Iddo; Cohen, Morrel H.

    2014-01-01

    An inverted rank distribution is an infinite sequence of positive sizes ordered in a monotone increasing fashion. Interlacing together Lorenzian and oligarchic asymptotic analyses, we establish a macroscopic classification of inverted rank distributions into five “socioeconomic” universality classes: communism, socialism, criticality, feudalism, and absolute monarchy. We further establish that: (i) communism and socialism are analogous to a “disordered phase”, feudalism and absolute monarchy are analogous to an “ordered phase”, and criticality is the “phase transition” between order and disorder; (ii) the universality classes are characterized by two critical exponents, one governing the ordered phase, and the other governing the disordered phase; (iii) communism, criticality, and absolute monarchy are characterized by sharp exponent values, and are inherently deterministic; (iv) socialism is characterized by a continuous exponent range, is inherently stochastic, and is universally governed by continuous power-law statistics; (v) feudalism is characterized by a continuous exponent range, is inherently stochastic, and is universally governed by discrete exponential statistics. The results presented in this paper yield a universal macroscopic socioeconophysical perspective of inverted rank distributions.

  16. Relating Lagrangian passive scalar scaling exponents to Eulerian scaling exponents in turbulence

    OpenAIRE

    Schmitt , François G

    2005-01-01

    Intermittency is a basic feature of fully developed turbulence, for both velocity and passive scalars. Intermittency is classically characterized by Eulerian scaling exponent of structure functions. The same approach can be used in a Lagrangian framework to characterize the temporal intermittency of the velocity and passive scalar concentration of a an element of fluid advected by a turbulent intermittent field. Here we focus on Lagrangian passive scalar scaling exponents, and discuss their p...

  17. Hurst exponent and prediction based on weak-form efficient market hypothesis of stock markets

    Science.gov (United States)

    Eom, Cheoljun; Choi, Sunghoon; Oh, Gabjin; Jung, Woo-Sung

    2008-07-01

    We empirically investigated the relationships between the degree of efficiency and the predictability in financial time-series data. The Hurst exponent was used as the measurement of the degree of efficiency, and the hit rate calculated from the nearest-neighbor prediction method was used for the prediction of the directions of future price changes. We used 60 market indexes of various countries. We empirically discovered that the relationship between the degree of efficiency (the Hurst exponent) and the predictability (the hit rate) is strongly positive. That is, a market index with a higher Hurst exponent tends to have a higher hit rate. These results suggested that the Hurst exponent is useful for predicting future price changes. Furthermore, we also discovered that the Hurst exponent and the hit rate are useful as standards that can distinguish emerging capital markets from mature capital markets.

  18. Exponent and scrambling index of double alternate circular snake graphs

    Science.gov (United States)

    Rahmayanti, Sri; Pasaribu, Valdo E.; Nasution, Sawaluddin; Liani Salnaz, Sishi

    2018-01-01

    A graph is primitive if it contains a cycle of odd length. The exponent of a primitive graph G, denoted by exp(G), is the smallest positive integer k such that for each pair of vertices u and v in G there is a uv-walk length k. The scrambling index of a primitive graph G, denoted by k(G), is the smallest positive integer k such that for each pair of vertices u and v in G there is a uv-walk of length 2k. For an even positive integer n and an odd positive integer r, a (n,r)-double alternate circular snake graph, denoted by DA(C r,n ), is a graph obtained from a path u 1 u 2 ... u n by replacing each edge of the form u 2i u 2i+1 by two different r-cycles. We study the exponent and scrambling index of DA(C r,n ) and show that exp(DA(C r,n )) = n + r - 4 and k(DA(C r,n )) = (n + r - 3)/2.

  19. Lyapunov exponent and criticality in the Hamiltonian mean field model

    Science.gov (United States)

    Filho, L. H. Miranda; Amato, M. A.; Rocha Filho, T. M.

    2018-03-01

    We investigate the dependence of the largest Lyapunov exponent (LLE) of an N-particle self-gravitating ring model at equilibrium with respect to the number of particles and its dependence on energy. This model has a continuous phase-transition from a ferromagnetic to homogeneous phase, and we numerically confirm with large scale simulations the existence of a critical exponent associated to the LLE, although at variance with the theoretical estimate. The existence of strong chaos in the magnetized state evidenced by a positive Lyapunov exponent is explained by the coupling of individual particle oscillations to the diffusive motion of the center of mass of the system and also results in a change of the scaling of the LLE with the number of particles. We also discuss thoroughly for the model the validity and limits of the approximations made by a geometrical model for their analytic estimate.

  20. Extending family nursing: concepts from positive psychology.

    Science.gov (United States)

    Skerrett, Karen

    2010-11-01

    This article identifies the burgeoning field of positive psychology as an important extension to the knowledge base of family nursing. Representing a new emphasis from the traditional social and human sciences, which have largely focused on problem- and deficit-based approaches, positive psychology focuses on optimal functioning and is an ideal complement to the strengths-based orientation of family nursing. Domains of positive psychology are presented and exemplars of supporting research offered. Finally, suggestions are given for ways to apply concepts from positive psychology to family nursing practice, research, and education.

  1. Lyapunov exponent and topological entropy plateaus in piecewise linear maps

    International Nuclear Information System (INIS)

    Botella-Soler, V; Oteo, J A; Ros, J; Glendinning, P

    2013-01-01

    We consider a two-parameter family of piecewise linear maps in which the moduli of the two slopes take different values. We provide numerical evidence of the existence of some parameter regions in which the Lyapunov exponent and the topological entropy remain constant. Analytical proof of this phenomenon is also given for certain cases. Surprisingly however, the systems with that property are not conjugate as we prove by using kneading theory. (paper)

  2. Monte Carlo-based tail exponent estimator

    Science.gov (United States)

    Barunik, Jozef; Vacha, Lukas

    2010-11-01

    In this paper we propose a new approach to estimation of the tail exponent in financial stock markets. We begin the study with the finite sample behavior of the Hill estimator under α-stable distributions. Using large Monte Carlo simulations, we show that the Hill estimator overestimates the true tail exponent and can hardly be used on samples with small length. Utilizing our results, we introduce a Monte Carlo-based method of estimation for the tail exponent. Our proposed method is not sensitive to the choice of tail size and works well also on small data samples. The new estimator also gives unbiased results with symmetrical confidence intervals. Finally, we demonstrate the power of our estimator on the international world stock market indices. On the two separate periods of 2002-2005 and 2006-2009, we estimate the tail exponent.

  3. Robust uniform persistence in discrete and continuous dynamical systems using Lyapunov exponents.

    Science.gov (United States)

    Salceanu, Paul L

    2011-07-01

    This paper extends the work of Salceanu and Smith [12, 13] where Lyapunov exponents were used to obtain conditions for uniform persistence ina class of dissipative discrete-time dynamical systems on the positive orthant of R(m), generated by maps. Here a united approach is taken, for both discrete and continuous time, and the dissipativity assumption is relaxed. Sufficient conditions are given for compact subsets of an invariant part of the boundary of R(m+) to be robust uniform weak repellers. These conditions require Lyapunov exponents be positive on such sets. It is shown how this leads to robust uniform persistence. The results apply to the investigation of robust uniform persistence of the disease in host populations, as shown in an application.

  4. Quantum critical Hall exponents

    CERN Document Server

    Lütken, C A

    2014-01-01

    We investigate a finite size "double scaling" hypothesis using data from an experiment on a quantum Hall system with short range disorder [1-3]. For Hall bars of width w at temperature T the scaling form is w(-mu)T(-kappa), where the critical exponent mu approximate to 0.23 we extract from the data is comparable to the multi-fractal exponent alpha(0) - 2 obtained from the Chalker-Coddington (CC) model [4]. We also use the data to find the approximate location (in the resistivity plane) of seven quantum critical points, all of which closely agree with the predictions derived long ago from the modular symmetry of a toroidal sigma-model with m matter fields [5]. The value nu(8) = 2.60513 ... of the localisation exponent obtained from the m = 8 model is in excellent agreement with the best available numerical value nu(num) = 2.607 +/- 0.004 derived from the CC-model [6]. Existing experimental data appear to favour the m = 9 model, suggesting that the quantum Hall system is not in the same universality class as th...

  5. Nuclear multifragmentation critical exponents

    International Nuclear Information System (INIS)

    Bauer, W.; Friedman, W.A.; Univ. of Wisconsin, Madison, WI

    1995-01-01

    In a recent Letter, cited in a reference, the EoS collaboration presented data of fragmentation of 1 A GeV gold nuclei incident on carbon. By analyzing moments of the fragment charge distribution, the authors claim to determine the values of the critical exponents γ, β, and τ for finite nuclei. These data represent a crucial step forward in the understanding of the physics of nuclear fragmentation. However, as shown in this paper, the analysis presented in the cited reference is not sufficient to support the claim that the critical exponents for nuclear fragmentation have been unambiguously determined

  6. Diophantine exponents for mildly restricted approximation

    DEFF Research Database (Denmark)

    Bugeaud, Yann; Kristensen, Simon

    We are studying the Diophantine exponent defined for integers and a vector by letting , where is the scalar product and denotes the distance to the nearest integer and is the generalised cone consisting of all vectors with the height attained among the first coordinates. We show that the exponent...

  7. Merit exponents and control area diagrams in materials selection

    International Nuclear Information System (INIS)

    Zander, Johan; Sandstroem, Rolf

    2011-01-01

    Highlights: → Merit exponents are introduced to generalise the merit indices commonly used in materials selection. → The merit exponents can rank materials in general design situations. → To allow identification of the active merit exponent(s), control area diagrams are used. → Principles for generating the control area diagrams are presented. -- Abstract: Merit indices play a fundamental role in materials selection, since they enable ranking of materials. However, the conventional formulation of merit indices is associated with severe limitations. They are dependent on the explicit solution of the variables in the equations for the constraints from the design criteria. Furthermore, it is not always easy to determine which the controlling merit index is. To enable the ranking of materials in more general design cases, merit exponents are introduced as generalisations of the merit indices. Procedures are presented for how to compute the merit exponents numerically without having to solve equations algebraically. Merit exponents (and indices) are only valid in a certain range of property values. To simplify the identification of the controlling merit exponent, it is suggested that so called control area diagrams are used. These diagrams consist of a number of domains, each showing the active constraints and the controlling merit exponent. It is shown that the merit exponents play a crucial role when the control area diagram (CAD) is set up. The principles in the paper are developed for mechanically loaded components and are illustrated for engineering beams with two or three geometric variables.

  8. Evaluating Lyapunov exponent spectra with neural networks

    International Nuclear Information System (INIS)

    Maus, A.; Sprott, J.C.

    2013-01-01

    Highlights: • Cross-correlation is employed to remove spurious Lyapunov exponents from a spectrum. • Neural networks are shown to accurately model Lyapunov exponent spectra. • Neural networks compare favorably to local linear fits in modeling Lyapunov exponents. • Numerical experiments are performed with time series of varying length and noise. • Methods perform reasonably well on discrete time series. -- Abstract: A method using discrete cross-correlation for identifying and removing spurious Lyapunov exponents when embedding experimental data in a dimension greater than the original system is introduced. The method uses a distribution of calculated exponent values produced by modeling a single time series many times or multiple instances of a time series. For this task, global models are shown to compare favorably to local models traditionally used for time series taken from the Hénon map and delayed Hénon map, especially when the time series are short or contaminated by noise. An additional merit of global modeling is its ability to estimate the dynamical and geometrical properties of the original system such as the attractor dimension, entropy, and lag space, although consideration must be taken for the time it takes to train the global models

  9. Family Caregivers' Patterns of Positive and Negative Affect

    Science.gov (United States)

    Robertson, Suzanne M.; Zarit, Steven H.; Duncan, Larissa G.; Rovine, Michael J.; Femia, Elia E.

    2007-01-01

    Stressful and positive family caregiving experiences were examined as predictors of caregivers' patterns of positive and negative affect in a sample of families providing care for a relative with dementia (N = 234). Four affect pattern groups were identified: (a) Well Adjusted (i.e., high positive affect, low negative affect); (b) Ambiguous (i.e.,…

  10. Non-universal spreading exponents in a catalytic reaction model

    International Nuclear Information System (INIS)

    De Andrade, Marcelo F; Figueiredo, W

    2011-01-01

    We investigated the dependence of the spreading critical exponents and the ultimate survival probability exponent on the initial configuration of a nonequilibrium catalytic reaction model. The model considers the competitive reactions between two different monomers, A and B, where we take into account the energy couplings between nearest neighbor monomers, and the adsorption energies, as well as the temperature T of the catalyst. For each value of T the model shows distinct absorbing states, with different concentrations of the two monomers. Employing an epidemic analysis, we established the behavior of the spreading exponents as we started the Monte Carlo simulations with different concentrations of the monomers. The exponents were determined as a function of the initial concentration ρ A, ini of A monomers. We have also considered initial configurations with correlations for a fixed concentration of A monomers. From the determination of three spreading exponents, and the ultimate survival probability exponent, we checked the validity of the generalized hyperscaling relation for a continuous set of initial states, random and correlated, which are dependent on the temperature of the catalyst

  11. Uniform persistence and upper Lyapunov exponents for monotone skew-product semiflows

    International Nuclear Information System (INIS)

    Novo, Sylvia; Obaya, Rafael; Sanz, Ana M

    2013-01-01

    Several results of uniform persistence above and below a minimal set of an abstract monotone skew-product semiflow are obtained. When the minimal set has a continuous separation the results are given in terms of the principal spectrum. In the case that the semiflow is generated by the solutions of a family of non-autonomous differential equations of ordinary, delay or parabolic type, the former results are strongly improved. A method of calculus of the upper Lyapunov exponent of the minimal set is also determined. (paper)

  12. Multiscale Lyapunov exponent for 2-microlocal functions

    International Nuclear Information System (INIS)

    Dhifaoui, Zouhaier; Kortas, Hedi; Ammou, Samir Ben

    2009-01-01

    The Lyapunov exponent is an important indicator of chaotic dynamics. Using wavelet analysis, we define a multiscale representation of this exponent which we demonstrate the scale-wise dependence for functions belonging to C x 0 s,s ' spaces. An empirical study involving simulated processes and financial time series corroborates the theoretical findings.

  13. The Critical Exponent is Computable for Automatic Sequences

    Directory of Open Access Journals (Sweden)

    Jeffrey Shallit

    2011-08-01

    Full Text Available The critical exponent of an infinite word is defined to be the supremum of the exponent of each of its factors. For k-automatic sequences, we show that this critical exponent is always either a rational number or infinite, and its value is computable. This generalizes or recovers previous results of Krieger and others. Our technique is applicable to other situations; e.g., the computation of the optimal recurrence constant for a linearly recurrent k-automatic sequence.

  14. Lyapunov exponents and smooth ergodic theory

    CERN Document Server

    Barreira, Luis

    2001-01-01

    This book is a systematic introduction to smooth ergodic theory. The topics discussed include the general (abstract) theory of Lyapunov exponents and its applications to the stability theory of differential equations, stable manifold theory, absolute continuity, and the ergodic theory of dynamical systems with nonzero Lyapunov exponents (including geodesic flows). The authors consider several non-trivial examples of dynamical systems with nonzero Lyapunov exponents to illustrate some basic methods and ideas of the theory. This book is self-contained. The reader needs a basic knowledge of real analysis, measure theory, differential equations, and topology. The authors present basic concepts of smooth ergodic theory and provide complete proofs of the main results. They also state some more advanced results to give readers a broader view of smooth ergodic theory. This volume may be used by those nonexperts who wish to become familiar with the field.

  15. Cryptanalysis of 'less short' RSA secret exponents

    NARCIS (Netherlands)

    Verheul, E.R.; Tilborg, van H.C.A.

    1997-01-01

    In some applications of RSA, it is desirable to have a short secret exponent d. Wiener [6], describes a technique to use continued fractions (CF) in a cryptanalytic attack on an RSA cryptosystem having a ‘short’ secret exponent. Let n=p¿·¿q be the modulus of the system. In the typical case that

  16. Types of work-family interface: well-being correlates of negative and positive spillover between work and family.

    Science.gov (United States)

    Kinnunen, Ulla; Feldt, Taru; Geurts, Sabine; Pulkkinen, Lea

    2006-04-01

    The aim of the present study was to test the structure of the work-family interface measure, which was intended to take into account both the positive and negative spillover between work and family demands in both directions. In addition, the links among the types of work-family spillover and the subjects' general and domain-specific well-being were examined. The sample (n = 202) consisted of Finnish employees, aged 42, who had a spouse/partner. Confirmatory factor analyses indicated that a four-factor model, including negative work-to-family spillover, negative family-to-work spillover, positive work-to-family spillover, and positive family-to-work spillover, was superior compared to the other factor models examined. Path analysis showed, as hypothesized, that the negative work-to-family spillover was most strongly related to low well-being at work (job exhaustion) and next strongly to low general well-being (psychological distress), whereas the negative family-to-work spillover was associated with low well-being in the domain of family (marital dissatisfaction). Positive work-to-family spillover was positively related both to well-being at work and general well-being. Inconsistent with our expectations, positive family-to-work spillover was not directly related to any of the well-being indicators examined.

  17. Family Life Satisfaction across Positional Roles, Family Development Categories and SES.

    Science.gov (United States)

    Tiffany, Phyllis G.

    Marital satisfaction across the life cycle differs for men and women. To investigate family life satisfaction across positional roles, developmental categories, and socioeconomic status (SES), 100 husbands and wives (families) were administered the Heimler Schedule of Social Functioning (SOSF), which relates social function and stressors (work,…

  18. Positive Youth Development within a Family Leisure Context: Youth Perspectives of Family Outcomes

    Science.gov (United States)

    Ward, Peter J.; Zabriskie, Ramon B.

    2011-01-01

    Family leisure involvement may provide the first and most essential context for positive youth development in today's society. Similar to the broader ecological perspective used in the youth development literature, family systems theory suggests that each individual in the family influences the whole, while the whole family also influences each…

  19. Family correlates of depression among hiv positive patients ...

    African Journals Online (AJOL)

    Background information: HIV infection may impact negatively on family relationship and vice versa. Members of the family of HIV positive patients may become frustrated because of the stigma of having a family member with HIV infection, and the burden of having to care for the patient. This can result into the family ...

  20. What is the cementation exponent? A new differential interpretation

    Science.gov (United States)

    Glover, P. W. J.

    2009-04-01

    Between 1950 and 2002 the total volume of reserves discovered has run to over 1500 Bbbl. for oil and 7.5 Tcf. for gas. Over half of these resources has already been produced, and has driven the global economy for the last fifty years. All of the assessments of the volume of hydrocarbon reserves were made using Archie's relationships (1942). It would be difficult, therefore, to overestimate the impact of either the petrophysical techniques or Archie's relationships on the worldwide economy. Archie's laws link the electrical resistivity of a rock to its porosity, to the resistivity of the water that saturates its pores, and to the fractional saturation of the pore space with the water, and are used to calculate the hydrocarbon saturation of the reservoir rock from which the reserves are then calculated. Archie's laws contain two exponents, m and n, which Archie called the cementation exponent and the saturation exponent, respectively. The conductivity of the hydrocarbon saturated rock is highly sensitive to changes in either exponent. However, despite the importance of the cementation exponent, few petrophysicists, commercial or academic, are able to describe its real physical meaning. The purpose of this contribution is to investigate the elusive physical meaning of the cementation exponent. We review the traditional interpretation of the cementation exponent and consider the extension of Archie's first law to two conducting phases. Consequently, we develop a new differential interpretation of the cementation exponent that is based on a new definition for the connectedness of the conducting phases in a porous medium. In this interpretation the connectedness of a porous medium is defined as the availability of pathways for transport, where the connectedness is the inverse of the formation resistivity factor, G = σo σw = 1 F (and may also be called the conductivity formation factor). Porosity is defined as the fractional amount of pore space in the usual manner

  1. A new theoretical interpretation of Archie's saturation exponent

    Directory of Open Access Journals (Sweden)

    P. W. J. Glover

    2017-07-01

    Full Text Available This paper describes the extension of the concepts of connectedness and conservation of connectedness that underlie the generalized Archie's law for n phases to the interpretation of the saturation exponent. It is shown that the saturation exponent as defined originally by Archie arises naturally from the generalized Archie's law. In the generalized Archie's law the saturation exponent of any given phase can be thought of as formally the same as the phase (i.e. cementation exponent, but with respect to a reference subset of phases in a larger n-phase medium. Furthermore, the connectedness of each of the phases occupying a reference subset of an n-phase medium can be related to the connectedness of the subset itself by Gi = GrefSini. This leads naturally to the idea of the term Sini for each phase i being a fractional connectedness, where the fractional connectednesses of any given reference subset sum to unity in the same way that the connectednesses sum to unity for the whole medium. One of the implications of this theory is that the saturation exponent of any phase can be now be interpreted as the rate of change of the fractional connectedness with saturation and connectivity within the reference subset.

  2. A new exponent in self-avoiding walks

    International Nuclear Information System (INIS)

    Srivastava, V.

    1983-06-01

    Existence of a new exponent is reported in the problem of nonintersecting self-avoiding random walks. It is connected with the asymptotic behaviour of the growth of number of such walks of larger and larger length. The value of the exponent is found to be nearly 0.90 for all two-dimensional and nearly 0.96 for all three-dimensional lattices studied here. (author)

  3. Effective Power-Law Dependence of Lyapunov Exponents on the Central Mass in Galaxies

    Science.gov (United States)

    Delis, N.; Efthymiopoulos, C.; Kalapotharakos, C.

    2015-01-01

    Using both numerical and analytical approaches, we demonstrate the existence of an effective power-law relation L alpha m(sup p) between themean Lyapunov exponent L of stellar orbits chaotically scattered by a supermassive black hole (BH) in the centre of a galaxy and the mass parameter m, i.e. ratio of the mass of the BH over the mass of the galaxy. The exponent p is found numerically to obtain values in the range p approximately equals 0.3-0.5. We propose a theoretical interpretation of these exponents, based on estimates of local 'stretching numbers', i.e. local Lyapunov exponents at successive transits of the orbits through the BH's sphere of influence. We thus predict p = 2/3 - q with q approximately equaling 0.1-0.2. Our basic model refers to elliptical galaxy models with a central core. However, we find numerically that an effective power-law scaling of L with m holds also in models with central cusp, beyond a mass scale up to which chaos is dominated by the influence of the cusp itself. We finally show numerically that an analogous law exists also in disc galaxies with rotating bars. In the latter case, chaotic scattering by the BH affects mainly populations of thick tube-like orbits surrounding some low-order branches of the x(sub 1) family of periodic orbits, as well as its bifurcations at low-order resonances, mainly the inner Lindblad resonance and the 4/1 resonance. Implications of the correlations between L and m to determining the rate of secular evolution of galaxies are discussed.

  4. Family planning and social position of women.

    Science.gov (United States)

    Begum, Hasna

    1993-04-01

    This presentation began with at least three biases: (i) Acceptance of a secular approach to the problem of artificially controlling human reproduction; (ii) acceptance of an absolute egalitarian position in matter of choices and applications of family planning methods; and (iii) acceptance of the view that a small family gives women more opportunities to flourish as humans. The conclusion of the presentation is: though in implementing family planning programmes much deviation from the egalitarian principle could be found, in reality the implementation itself does bring about some opportunities for women to enhance their position in society. Undoubtedly the malpractices in family planning programmes cause death and miseries to women. But, until better methods are invented for both male and female sexes to replace the harmful ones and the male members of the society feel equal responsibility in matters of controlling reproduction, women have now no other choice but to accept the lesser evil.

  5. How We Tend To Overestimate Powerlaw Tail Exponents

    OpenAIRE

    Nassim N. Taleb

    2012-01-01

    In the presence of a layer of metaprobabilities (from uncertainty concerning the parameters), the asymptotic tail exponent corresponds to the lowest possible tail exponent regardless of its probability. The problem explains "Black Swan" effects, i.e., why measurements tend to chronically underestimate tail contributions, rather than merely deliver imprecise but unbiased estimates.

  6. Positive family history of aortic dissection dramatically increases dissection risk in family members.

    Science.gov (United States)

    Ma, Wei-Guo; Chou, Alan S; Mok, Salvior C M; Ziganshin, Bulat A; Charilaou, Paris; Zafar, Mohammad A; Sieller, Richard S; Tranquilli, Maryann; Rizzo, John A; Elefteriades, John A

    2017-08-01

    Although family members of patients with aortic dissection (AoD) are believed to be at higher risk of AoD, the prognostic value of family history (FH) of aortic dissection (FHAD) in family members of patients with AoD has not been studied rigorously. We seek examine how much a positive FHAD increases the risk of developing new aortic dissection (AoD) among first-degree relatives. Patients with AoD at our institution were analyzed for information of FHAD. Positive FHAD referred to that AoD occurred in index patient and one or more first-degree relatives. Negative FHAD was defined as the condition in which only one case of AoD (the index patient) occurred in the family. The age at AoD, exposure years in adulthood before AoD, and annual probability of AoD among first-degree relatives were compared between patients with negative and positive FHADs. FHAD was positive in 32 and negative in 68 among the 100 AoD patients with detailed family history information. Mean age at dissection was 59.9±14.7years. Compared to negative FHAD, patients with positive FHAD dissected at significantly younger age (54.7±16.8 vs 62.4±13.0years, p=0.013), had more AoD events in first-degree relatives (2.3±0.6 vs 1.0±0.0, pfamily members, with a higher annual probability of aortic dissection, a shorter duration of "exposure time" before dissection occurs and a lower mean age at time of dissection. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

  7. Lyapunov, attractors and exponents

    International Nuclear Information System (INIS)

    Oliveira, C.R. de.

    1987-01-01

    Based on the fundamental principles of statistical mechanics and ergodic theory a definition is given to atractor, as an invariant measure. Many results which reinforce this definition are demonstrated. Chaos is related to the presence of an atractor with entropy above zero. The role of Lyapunov exponents is analyzed. (A.C.A.S.) [pt

  8. [Characteristics of HBV transmission in families with HBsAg-positive fathers and familial clustering of HBV infection].

    Science.gov (United States)

    Yang, Y; Jin, L; He, Y L; Liu, J F; Wang, J; Wang, K; Ma, X H; Li, Q; Feng, Y L; Yan, Z; Yi, R T; Chen, T Y; Zhao, Y R

    2016-04-01

    To investigate the characteristics of hepatitis B virus (HBV) transmission among family members in families with familial clustering of HBV infection and poor outcomes, as well as the prevalence and distribution characteristics of HBsAg in offspring with different parental HBsAg status. The general information of each member in families with poor outcomes were collected from 2007 to 2010, and serological test was performed to analyze the prevalence and distribution of HBsAg in family members. The chi-square test or Fisher's exact test was used to analyze and compare the sex of offspring and the prevalence of HBsAg in them in 266 nuclear families with different paternal and maternal HBsAg status. The positive rates of HBsAg in parents, siblings, children, and spouses of the probands were 20%, 88.2%, 76.8%, and 9.5%, respectively. The nuclear families with HBsAg-positive fathers and HBsAg-negative mothers had a significantly increased proportion of male offspring (male/female ratio = 2.02) compared with those with HBsAg-positive mothers and HBsAg-negative fathers (1.22) or those with HBsAg-negative fathers and mothers (0.96). In addition, in the nuclear families with HBsAg-positive fathers and HBsAg-negative mothers, the male offspring had a significantly higher HBsAg positive rate than female offspring (37.4% vs 13.8%), while in those with HBsAg-positive mothers and HBsAg-negative fathers or those with HBsAg-negative fathers and mothers, HBsAg positive rate showed no significant difference between male and female offspring. In families with familial clustering of HBV infection and poor outcomes, mother-to-child transmission is still the major route of HBV transmission, but father-to-child transmission also plays a role in HBV transmission in this special population. Positive HBsAg in fathers is associated with the increased proportion of male offspring, and father-to-son transmission of HBV is higher than father-to-daughter transmission.

  9. Lyapunov exponents

    CERN Document Server

    Barreira, Luís

    2017-01-01

    This book offers a self-contained introduction to the theory of Lyapunov exponents and its applications, mainly in connection with hyperbolicity, ergodic theory and multifractal analysis. It discusses the foundations and some of the main results and main techniques in the area, while also highlighting selected topics of current research interest. With the exception of a few basic results from ergodic theory and the thermodynamic formalism, all the results presented include detailed proofs. The book is intended for all researchers and graduate students specializing in dynamical systems who are looking for a comprehensive overview of the foundations of the theory and a sample of its applications.

  10. On the Lojasiewicz exponent at infinity of real polynomials

    International Nuclear Information System (INIS)

    Ha Huy Vui; Pham Tien Son

    2007-07-01

    Let f : R n → R be a nonconstant polynomial function. In this paper, using the information from 'the curve of tangency' of f, we provide a method to determine the Lojasiewicz exponent at infinity of f. As a corollary, we give a computational criterion to decide if the Lojasiewicz exponent at infinity is finite or not. Then, we obtain a formula to calculate the set of points at which the polynomial f is not proper. Moreover, a relation between the Lojasiewicz exponent at infinity of f with the problem of computing the global optimum of f is also established. (author)

  11. Hyperbolicity and integral expression of the Lyapunov exponents for linear cocycles

    Science.gov (United States)

    Dai, Xiongping

    Consider in this paper a linear skew-product system (θ,Θ) :T×W×R→W×R; (t,w,x)↦(tw,Θ(t,w)ṡx) where T=R or Z, and θ :(t,w)↦tw is a topological dynamical system on a compact metrizable space W, and where Θ(t,w)∈GL(n,R) satisfies the cocycle condition based on θ and is continuously differentiable in t if T=R. We show that 'semi λ-exponential dichotomy' of (θ,Θ) implies ' λ-exponential dichotomy.' Precisely, if Θ has no Lyapunov exponent λ and is almost uniformly λ-contracting along the λ-stable direction E(w;λ) and if dimE(w;λ) is constant a.e., then Θ is almost λ-exponentially dichotomous. To prove this, we first use Liao's spectrum theorem, which gives integral expression of the Lyapunov exponents, and then use the semi-uniform ergodic theorem by Sturman and Stark, which allows one to derive uniform estimates from nonuniform ones. As a consequence, we obtain the open-and-dense hyperbolicity of eventual GL(2,R)-cocycles based on a uniquely ergodic endomorphism, and of GL(2,R)-cocycles based on a uniquely ergodic equi-continuous endomorphism, respectively. On the other hand, in the sense of C-topology we obtain the density of SL(2,R)-cocycles having positive Lyapunov exponent based on a minimal subshift satisfying the Boshernitzan condition.

  12. OBSERVING LYAPUNOV EXPONENTS OF INFINITE-DIMENSIONAL DYNAMICAL SYSTEMS.

    Science.gov (United States)

    Ott, William; Rivas, Mauricio A; West, James

    2015-12-01

    Can Lyapunov exponents of infinite-dimensional dynamical systems be observed by projecting the dynamics into ℝ N using a 'typical' nonlinear projection map? We answer this question affirmatively by developing embedding theorems for compact invariant sets associated with C 1 maps on Hilbert spaces. Examples of such discrete-time dynamical systems include time- T maps and Poincaré return maps generated by the solution semigroups of evolution partial differential equations. We make every effort to place hypotheses on the projected dynamics rather than on the underlying infinite-dimensional dynamical system. In so doing, we adopt an empirical approach and formulate checkable conditions under which a Lyapunov exponent computed from experimental data will be a Lyapunov exponent of the infinite-dimensional dynamical system under study (provided the nonlinear projection map producing the data is typical in the sense of prevalence).

  13. Hypergeometric continuation of divergent perturbation series: I. Critical exponents of the Bose–Hubbard model

    International Nuclear Information System (INIS)

    Sanders, Sören; Holthaus, Martin

    2017-01-01

    We study the connection between the exponent of the order parameter of the Mott insulator-to-superfluid transition occurring in the two-dimensional Bose–Hubbard model, and the divergence exponents of its one- and two-particle correlation functions. We find that at the multicritical points all divergence exponents are related to each other, allowing us to express the critical exponent in terms of one single divergence exponent. This approach correctly reproduces the critical exponent of the three-dimensional XY universality class. Because divergence exponents can be computed in an efficient manner by hypergeometric analytic continuation, our strategy is applicable to a wide class of systems. (paper)

  14. Hypergeometric continuation of divergent perturbation series: I. Critical exponents of the Bose-Hubbard model

    Science.gov (United States)

    Sanders, Sören; Holthaus, Martin

    2017-10-01

    We study the connection between the exponent of the order parameter of the Mott insulator-to-superfluid transition occurring in the two-dimensional Bose-Hubbard model, and the divergence exponents of its one- and two-particle correlation functions. We find that at the multicritical points all divergence exponents are related to each other, allowing us to express the critical exponent in terms of one single divergence exponent. This approach correctly reproduces the critical exponent of the three-dimensional XY universality class. Because divergence exponents can be computed in an efficient manner by hypergeometric analytic continuation, our strategy is applicable to a wide class of systems.

  15. The critical 1-arm exponent for the ferromagnetic Ising model on the Bethe lattice

    Science.gov (United States)

    Heydenreich, Markus; Kolesnikov, Leonid

    2018-04-01

    We consider the ferromagnetic nearest-neighbor Ising model on regular trees (Bethe lattice), which is well-known to undergo a phase transition in the absence of an external magnetic field. The behavior of the model at critical temperature can be described in terms of various critical exponents; one of them is the critical 1-arm exponent ρ which characterizes the rate of decay of the (root) magnetization as a function of the distance to the boundary. The crucial quantity we analyze in this work is the thermal expectation of the root spin on a finite subtree, where the expected value is taken with respect to a probability measure related to the corresponding finite-volume Hamiltonian with a fixed boundary condition. The spontaneous magnetization, which is the limit of this thermal expectation in the distance between the root and the boundary (i.e., in the height of the subtree), is known to vanish at criticality. We are interested in a quantitative analysis of the rate of this convergence in terms of the critical 1-arm exponent ρ. Therefore, we rigorously prove that ⟨σ0⟩ n +, the thermal expectation of the root spin at the critical temperature and in the presence of the positive boundary condition, decays as ⟨σ0 ⟩ n +≈n-1/2 (in a rather sharp sense), where n is the height of the tree. This establishes the 1-arm critical exponent for the Ising model on regular trees (ρ =1/2 ).

  16. Lyapunov exponents for infinite dimensional dynamical systems

    Science.gov (United States)

    Mhuiris, Nessan Mac Giolla

    1987-01-01

    Classically it was held that solutions to deterministic partial differential equations (i.e., ones with smooth coefficients and boundary data) could become random only through one mechanism, namely by the activation of more and more of the infinite number of degrees of freedom that are available to such a system. It is only recently that researchers have come to suspect that many infinite dimensional nonlinear systems may in fact possess finite dimensional chaotic attractors. Lyapunov exponents provide a tool for probing the nature of these attractors. This paper examines how these exponents might be measured for infinite dimensional systems.

  17. The hurst exponent and long-time correlation

    International Nuclear Information System (INIS)

    Wang, G.; Antar, G.; Devynck, P.

    1999-10-01

    The rescaled range statistics (R/S) method is applied to the ion saturation current fluctuations measured by Langmuir probe at edge on Tore Supra to evaluate the Hurst exponent. Data block randomization is carried out to the data sets in order to investigate the relationship between the Hurst exponent and long time correlation. It is observed that h is well above 0.5 in the long time self-similar range. However, it is found that the information which leads to H > 0.5 is totally contained in the short-time correlation and no link to long times is found. (authors)

  18. Subdiffusive master equation with space-dependent anomalous exponent and structural instability

    Science.gov (United States)

    Fedotov, Sergei; Falconer, Steven

    2012-03-01

    We derive the fractional master equation with space-dependent anomalous exponent. We analyze the asymptotic behavior of the corresponding lattice model both analytically and by Monte Carlo simulation. We show that the subdiffusive fractional equations with constant anomalous exponent μ in a bounded domain [0,L] are not structurally stable with respect to the nonhomogeneous variations of parameter μ. In particular, the Gibbs-Boltzmann distribution is no longer the stationary solution of the fractional Fokker-Planck equation whatever the space variation of the exponent might be. We analyze the random distribution of μ in space and find that in the long-time limit, the probability distribution is highly intermediate in space and the behavior is completely dominated by very unlikely events. We show that subdiffusive fractional equations with the nonuniform random distribution of anomalous exponent is an illustration of a “Black Swan,” the low probability event of the small value of the anomalous exponent that completely dominates the long-time behavior of subdiffusive systems.

  19. When Patients Divorce: The Family Physician's Legal Position

    OpenAIRE

    Mesbur, Ruth E.

    1983-01-01

    When divorce and family disintegration loom, the family physician is often the first outsider on the scene. The family physician may, indeed, have a critical role to play in handling the crisis; he may advise, refer to other professionals like therapists or lawyers, or appear in court as an expert witness. The physician must consider his legal position. Is reconciliation counselling confidential, privileged information? Can he recommend a lawyer for a patient? What is the physician's vulnerab...

  20. Condensation and critical exponents of an ideal non-Abelian gas

    Science.gov (United States)

    Talaei, Zahra; Mirza, Behrouz; Mohammadzadeh, Hosein

    2017-11-01

    We investigate an ideal gas obeying non-Abelian statistics and derive the expressions for some thermodynamic quantities. It is found that thermodynamic quantities are finite at the condensation point where their derivatives diverge and, near this point, they behave as \\vert T-Tc\\vert^{-ρ} in which Tc denotes the condensation temperature and ρ is a critical exponent. The critical exponents related to the heat capacity and compressibility are obtained by fitting numerical results and others are obtained using the scaling law hypothesis for a three-dimensional non-Abelian ideal gas. This set of critical exponents introduces a new universality class.

  1. Analysis of Human Standing Balance by Largest Lyapunov Exponent

    Directory of Open Access Journals (Sweden)

    Kun Liu

    2015-01-01

    Full Text Available The purpose of this research is to analyse the relationship between nonlinear dynamic character and individuals’ standing balance by the largest Lyapunov exponent, which is regarded as a metric for assessing standing balance. According to previous study, the largest Lyapunov exponent from centre of pressure time series could not well quantify the human balance ability. In this research, two improvements were made. Firstly, an external stimulus was applied to feet in the form of continuous horizontal sinusoidal motion by a moving platform. Secondly, a multiaccelerometer subsystem was adopted. Twenty healthy volunteers participated in this experiment. A new metric, coordinated largest Lyapunov exponent was proposed, which reflected the relationship of body segments by integrating multidimensional largest Lyapunov exponent values. By using this metric in actual standing performance under sinusoidal stimulus, an obvious relationship between the new metric and the actual balance ability was found in the majority of the subjects. These results show that the sinusoidal stimulus can make human balance characteristics more obvious, which is beneficial to assess balance, and balance is determined by the ability of coordinating all body segments.

  2. Partial differential equations with variable exponents variational methods and qualitative analysis

    CERN Document Server

    Radulescu, Vicentiu D

    2015-01-01

    Partial Differential Equations with Variable Exponents: Variational Methods and Qualitative Analysis provides researchers and graduate students with a thorough introduction to the theory of nonlinear partial differential equations (PDEs) with a variable exponent, particularly those of elliptic type. The book presents the most important variational methods for elliptic PDEs described by nonhomogeneous differential operators and containing one or more power-type nonlinearities with a variable exponent. The authors give a systematic treatment of the basic mathematical theory and constructive meth

  3. Local Lyapunov exponents for dissipative continuous systems

    International Nuclear Information System (INIS)

    Grond, Florian; Diebner, Hans H.

    2005-01-01

    We analyze a recently proposed algorithm for computing Lyapunov exponents focusing on its capability to calculate reliable local values for chaotic attractors. The averaging process of local contributions to the global measure becomes interpretable, i.e. they are related to the local topological structure in phase space. We compare the algorithm with the commonly used Wolf algorithm by means of analyzing correlations between coordinates of the chaotic attractor and local values of the Lyapunov exponents. The correlations for the new algorithm turn out to be significantly stronger than those for the Wolf algorithm. Since the usage of scalar measures to capture complex structures can be questioned we discuss these entities along with a more phenomenological description of scatter plots

  4. Adaptive control of nonlinear in parameters chaotic system via Lyapunov exponents placement

    Energy Technology Data Exchange (ETDEWEB)

    Ayati, Moosa [Department of Electrical Engineering, K.N. Toosi University of Technology, Sayyed Khandan Bridge, Shariati Street, Tehran (Iran, Islamic Republic of)], E-mail: Ayati@dena.kntu.ac.ir; Khaki-Sedigh, Ali [Department of Electrical Engineering, K.N. Toosi University of Technology, Sayyed Khandan Bridge, Shariati Street, Tehran (Iran, Islamic Republic of)], E-mail: sedigh@kntu.ac.ir

    2009-08-30

    This paper proposes a new method for the adaptive control of nonlinear in parameters (NLP) chaotic systems. A method based on Lagrangian of a cost function is used to identify the parameters of the system. Estimation results are used to calculate the Lyapunov exponents adaptively. Finally, the Lyapunov exponents placement method is used to assign the desired Lyapunov exponents of the closed loop system.

  5. Adaptive control of nonlinear in parameters chaotic system via Lyapunov exponents placement

    International Nuclear Information System (INIS)

    Ayati, Moosa; Khaki-Sedigh, Ali

    2009-01-01

    This paper proposes a new method for the adaptive control of nonlinear in parameters (NLP) chaotic systems. A method based on Lagrangian of a cost function is used to identify the parameters of the system. Estimation results are used to calculate the Lyapunov exponents adaptively. Finally, the Lyapunov exponents placement method is used to assign the desired Lyapunov exponents of the closed loop system.

  6. Spacetime dependence of the anomalous exponent of electric transport in the disorder model

    International Nuclear Information System (INIS)

    Egami, Takeshi; Suzuki, Koshiro; Watanabe, Katsuhiro

    2012-01-01

    Spacetime dependence of the anomalous exponent of electric transport in the disorder model is investigated. We show that the anomalous exponent evolves with time, according to the time evolution of the number of the effective neighbouring sites. Transition from subdiffusive to normal transport is recovered at macroscopic timescales. Plateaus appear in the history of the anomalous exponent due to the discreteness of the hopping sites, which is compatible with the conventional treatment to regard the anomalous exponent as a constant. We also show that, among various microscopic spatial structures, the number of the effective neighbouring sites is the only element which determines the anomalous exponent. This is compatible with the mesoscopic model of Scher–Montroll. These findings are verified by means of Monte Carlo simulation. The well-known expression of the anomalous exponent in the conventional multiple trapping model is derived by deducing it as a special case of the disorder model. (paper)

  7. [The physical development of children in families with different financial position].

    Science.gov (United States)

    Leonova, I A; Khomich, M M

    2010-01-01

    Physical development is one of the important health indices in children. Anthropometric data were analyzed in 660 and 113 children from rich and poor families, respectively. The performed investigation revealed the following features of physical development of children in families with different financial position: (1) impaired physical development is equally common in the families with low (284.85% per hundred) and high (292.04% per hundred) incomes (p > 0.05); (2) the pattern of distribution of different types of physical development is not determined by the financial position of a family; however, it may be noted that there is a preponderance of children with disharmonious development in the high-income families due to excess weight for both average age indices and height. Every seven child from a high-income family has excess weight. Naturally, the lower financial position of a family is, the higher proportion of children with nutritional state below the average low values is; (3) the children in low-income families have lower height. The revealed specific features may be largely accounted for by specific nutritional features and motor activity in children, which should be kept in mind in working out the programs on therapeutic-and-prophylactic work with these population categories.

  8. Anisotropies in magnetic field evolution and local Lyapunov exponents

    International Nuclear Information System (INIS)

    Tang, X.Z.; Boozer, A.H.

    2000-01-01

    The natural occurrence of small scale structures and the extreme anisotropy in the evolution of a magnetic field embedded in a conducting flow is interpreted in terms of the properties of the local Lyapunov exponents along the various local characteristic (un)stable directions for the Lagrangian flow trajectories. The local Lyapunov exponents and the characteristic directions are functions of Lagrangian coordinates and time, which are completely determined once the flow field is specified. The characteristic directions that are associated with the spatial anisotropy of the problem, are prescribed in both Lagrangian and Eulerian frames. Coordinate transformation techniques are employed to relate the spatial distributions of the magnetic field, the induced current density, and the Lorentz force, which are usually followed in Eulerian frame, to those of the local Lyapunov exponents, which are naturally defined in Lagrangian coordinates

  9. Laminar Flame Velocity and Temperature Exponent of Diluted DME-Air Mixture

    Science.gov (United States)

    Naseer Mohammed, Abdul; Anwar, Muzammil; Juhany, Khalid A.; Mohammad, Akram

    2017-03-01

    In this paper, the laminar flame velocity and temperature exponent diluted dimethyl ether (DME) air mixtures are reported. Laminar premixed mixture of DME-air with volumetric dilutions of carbon dioxides (CO2) and nitrogen (N2) are considered. Experiments were conducted using a preheated mesoscale high aspect-ratio diverging channel with inlet dimensions of 25 mm × 2 mm. In this method, flame velocities are extracted from planar flames that were stabilized near adiabatic conditions inside the channel. The flame velocities are then plotted against the ratio of mixture temperature and the initial reference temperature. A non-linear power law regression is observed suitable. This regression analysis gives the laminar flame velocity at the initial reference temperature and temperature exponent. Decrease in the laminar flame velocity and increase in temperature exponent is observed for CO2 and N2 diluted mixtures. The addition of CO2 has profound influence when compared to N2 addition on both flame velocity and temperature exponent. Numerical prediction of the similar mixture using a detailed reaction mechanism is obtained. The computational mechanism predicts higher magnitudes for laminar flame velocity and smaller magnitudes of temperature exponent compared to experimental data.

  10. A comment on measuring the Hurst exponent of financial time series

    Science.gov (United States)

    Couillard, Michel; Davison, Matt

    2005-03-01

    A fundamental hypothesis of quantitative finance is that stock price variations are independent and can be modeled using Brownian motion. In recent years, it was proposed to use rescaled range analysis and its characteristic value, the Hurst exponent, to test for independence in financial time series. Theoretically, independent time series should be characterized by a Hurst exponent of 1/2. However, finite Brownian motion data sets will always give a value of the Hurst exponent larger than 1/2 and without an appropriate statistical test such a value can mistakenly be interpreted as evidence of long term memory. We obtain a more precise statistical significance test for the Hurst exponent and apply it to real financial data sets. Our empirical analysis shows no long-term memory in some financial returns, suggesting that Brownian motion cannot be rejected as a model for price dynamics.

  11. Can the bivariate Hurst exponent be higher than an average of the separate Hurst exponents?

    Czech Academy of Sciences Publication Activity Database

    Krištoufek, Ladislav

    2015-01-01

    Roč. 431, č. 1 (2015), s. 124-127 ISSN 0378-4371 R&D Projects: GA ČR(CZ) GP14-11402P Institutional support: RVO:67985556 Keywords : Correlations * Power- law cross-correlations * Bivariate Hurst exponent * Spectrum coherence Subject RIV: AH - Economics Impact factor: 1.785, year: 2015 http://library.utia.cas.cz/separaty/2015/E/kristoufek-0452314.pdf

  12. Cultural influences on positive father involvement in two-parent Mexican-origin families.

    Science.gov (United States)

    Cruz, Rick A; King, Kevin M; Widaman, Keith F; Leu, Janxin; Cauce, Ana Mari; Conger, Rand D

    2011-10-01

    A growing body of research documents the importance of positive father involvement in children's development. However, research on fathers in Latino families is sparse, and research contextualizing the father-child relationship within a cultural framework is needed. The present study examined how fathers' cultural practices and values predicted their fifth-grade children's report of positive father involvement in a sample of 450 two-parent Mexican-origin families. Predictors included Spanish- and English-language use, Mexican and American cultural values, and positive machismo (i.e., culturally related attitudes about the father's role within the family). Positive father involvement was measured by the child's report of his or her father's monitoring, educational involvement, and warmth. Latent variable regression analyses showed that fathers' machismo attitudes were positively related to children's report of positive father involvement and that this association was similar across boys and girls. The results of this study suggest an important association between fathers' cultural values about men's roles and responsibilities within a family and their children's perception of positive fathering.

  13. Gender diversity in top-management positions in large family and nonfamily businesses

    OpenAIRE

    Kay, Rosemarie; Schlömer-Laufen, Nadine

    2016-01-01

    (Why) does the sex ratio in top-management positions in large family and nonfamily businesses differ? Using a unique data set and estimating (fractional) logit regressions we show that the female share in top-management positions in family businesses exceeds the one in nonfamily businesses. One reason is the selection mechanism social homophily from which females in family businesses benefit more because of a higher female share in the decision making body in family businesses. Another reason...

  14. Controlled test for predictive power of Lyapunov exponents: their inability to predict epileptic seizures.

    Science.gov (United States)

    Lai, Ying-Cheng; Harrison, Mary Ann F; Frei, Mark G; Osorio, Ivan

    2004-09-01

    Lyapunov exponents are a set of fundamental dynamical invariants characterizing a system's sensitive dependence on initial conditions. For more than a decade, it has been claimed that the exponents computed from electroencephalogram (EEG) or electrocorticogram (ECoG) signals can be used for prediction of epileptic seizures minutes or even tens of minutes in advance. The purpose of this paper is to examine the predictive power of Lyapunov exponents. Three approaches are employed. (1) We present qualitative arguments suggesting that the Lyapunov exponents generally are not useful for seizure prediction. (2) We construct a two-dimensional, nonstationary chaotic map with a parameter slowly varying in a range containing a crisis, and test whether this critical event can be predicted by monitoring the evolution of finite-time Lyapunov exponents. This can thus be regarded as a "control test" for the claimed predictive power of the exponents for seizure. We find that two major obstacles arise in this application: statistical fluctuations of the Lyapunov exponents due to finite time computation and noise from the time series. We show that increasing the amount of data in a moving window will not improve the exponents' detective power for characteristic system changes, and that the presence of small noise can ruin completely the predictive power of the exponents. (3) We report negative results obtained from ECoG signals recorded from patients with epilepsy. All these indicate firmly that, the use of Lyapunov exponents for seizure prediction is practically impossible as the brain dynamical system generating the ECoG signals is more complicated than low-dimensional chaotic systems, and is noisy. Copyright 2004 American Institute of Physics

  15. Critical exponents from the effective average action

    International Nuclear Information System (INIS)

    Tetradis, N.; Wetterich, C.

    1993-07-01

    We compute the critical behaviour of three-dimensional scalar theories using a new exact non-perturbative evolution equation. Our values for the critical exponents agree well with previous precision estimates. (orig.)

  16. On the Topological Changes of Local Hurst Exponent in Polar Regions

    Science.gov (United States)

    Consolini, G.; De Michelis, P.

    2014-12-01

    Geomagnetic activity during magnetic substorms and storms is related to the dinamical and topological changes of the current systems flowing in the Earth's magnetosphere-ionosphere. This is particularly true in the case of polar regions where the enhancement of auroral electrojet current system is responsible for the observed geomagnetic perturbations. Here, using the DMA-technique we evaluate the local Hurst exponent (H"older exponent) for a set of 46 geomagnetic observatories, widely distributed in the northern hemisphere, during one of the most famous and strong geomagnetic storm, the Bastille event, and reconstruct a sequence of polar maps showing the dinamical changes of the topology of the local Hurst exponent with the geomagnetic activity level. The topological evolution of local Hurst exponent maps is discussed in relation to the dinamical changes of the current systems flowing in the polar ionosphere. G. Consolini has received funding from the European Community's Seventh Framework Programme (FP7/2007-2013) under Grant agreement no. 313038/STORM for this research.

  17. Variation of CRE with exponents of time and number of fractions

    International Nuclear Information System (INIS)

    Supe, S.J.; Rao, S.M.; Sawant, S.G.; Bisht, J.S.

    1976-01-01

    The concept of NSD has been modified into TDF's by Orton and Ellis and CRE's by Kirk et al. It was aimed to study the variability of these new concepts on the exponents of time and number of fractions. It was found that TDF has larger variation with the exponents compared to that of CRE. The use of CRE and NSD for solving the treatment scheduling problems or for intercomparison of various regimes has been simplified by providing readymade estimation of CRE for various doses/fraction with increasing number of fractions. As there is increasing evidence for the change of exponents J and H, nomograms are presented to determine the CRE for various values of J and H. The variation of decay correction factors with the exponent H is also evaluated and is presented. This will help various radiotherapists to use CRE and the decay correction factors consistent with their clinical findings. (orig.) [de

  18. Perceived Family Support and Antiretroviral Adherence in HIV-Positive Individuals: Results from a Community-Based Positive Living With HIV Study.

    Science.gov (United States)

    Poudel, Krishna C; Buchanan, David R; Amiya, Rachel M; Poudel-Tandukar, Kalpana

    2015-01-01

    The purpose of this study was to examine the association between perceived family support, either positive or negative, and adherence to antiretroviral medication regimens among HIV-positive individuals in the Kathmandu Valley, Nepal. We measured past 3-month antiretroviral adherence among 233 HIV-positive individuals, in relation to perceived family support, both positive (in terms of emotional and instrumental support) and negative (in the form of negative interactions), using the 10-item Nepali Family Support and Difficulty Scale. Medium and high levels of perceived emotional support from family were associated with reduced risk of antiretroviral nonadherence, compared with low levels of perceived emotional support (adjusted odds ratio [AOR]  = 0.37, 95% confidence interval [CI] [0.16, 0.88], and AOR  = 0.23, 95% CI [0.08, 0.64], respectively). Conversely, higher levels of felt emotional distance (AOR  = 1.46, 95% CI [1.00, 2.14]) and experienced physical harm (AOR  = 2.04, 95% CI [1.07, 3.91]) were associated with increased risk of nonadherence. The results support the recommendation that service providers need to be aware of the significant role of family support in shaping antiretroviral adherence and to consider ways to strengthen positive family support while minimizing negative family interactions to increase adherence rates. © The Author(s) 2015.

  19. Four-loop critical exponents for the Gross-Neveu-Yukawa models

    International Nuclear Information System (INIS)

    Zerf, Nikolai; Mihaila, Luminita N.; Herbut, Igor F.; Scherer, Michael M.

    2017-09-01

    We study the chiral Ising, the chiral XY and the chiral Heisenberg models at four-loop order with the perturbative renormalization group in 4-ε dimensions and compute critical exponents for the Gross-Neveu-Yukawa fixed points to order O(ε 4 ). Further, we provide Pade estimates for the correlation length exponent, the boson and fermion anomalous dimension as well as the leading correction to scaling exponent in 2+1 dimensions. We also confirm the emergence of supersymmetric field theories at four loops for the chiral Ising and the chiral XY models with N=1/4 and N=1/2 fermions, respectively. Furthermore, applications of our results relevant to various quantum transitions in the context of Dirac and Weyl semimetals are discussed, including interaction-induced transitions in graphene and surface states of topological insulators.

  20. Four-loop critical exponents for the Gross-Neveu-Yukawa models

    Energy Technology Data Exchange (ETDEWEB)

    Zerf, Nikolai; Mihaila, Luminita N. [Heidelberg Univ. (Germany). Inst. fuer Theoretische Physik; Marquard, Peter [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany); Herbut, Igor F. [Simon Fraser Univ., Burnaby, BC (Canada). Dept. of Physics; Scherer, Michael M. [Koeln Univ. (Germany). Inst. for Theoretical Physics

    2017-09-15

    We study the chiral Ising, the chiral XY and the chiral Heisenberg models at four-loop order with the perturbative renormalization group in 4-ε dimensions and compute critical exponents for the Gross-Neveu-Yukawa fixed points to order O(ε{sup 4}). Further, we provide Pade estimates for the correlation length exponent, the boson and fermion anomalous dimension as well as the leading correction to scaling exponent in 2+1 dimensions. We also confirm the emergence of supersymmetric field theories at four loops for the chiral Ising and the chiral XY models with N=1/4 and N=1/2 fermions, respectively. Furthermore, applications of our results relevant to various quantum transitions in the context of Dirac and Weyl semimetals are discussed, including interaction-induced transitions in graphene and surface states of topological insulators.

  1. Statistical-mechanical formulation of Lyapunov exponents

    International Nuclear Information System (INIS)

    Tanase-Nicola, Sorin; Kurchan, Jorge

    2003-01-01

    We show how the Lyapunov exponents of a dynamic system can, in general, be expressed in terms of the free energy of a (non-Hermitian) quantum many-body problem. This puts their study as a problem of statistical mechanics, whose intuitive concepts and techniques of approximation can hence be borrowed

  2. Fujita Exponent for a Nonlinear Degenerate Parabolic Equation with Localized Source

    Directory of Open Access Journals (Sweden)

    Yulan Wang

    2014-01-01

    Full Text Available This paper is devoted to understand the blow-up properties of reaction-diffusion equations which combine a localized reaction term with nonlinear diffusion. In particular, we study the critical exponent of a p-Laplacian equation with a localized reaction. We obtain the Fujita exponent qc of the equation.

  3. High-accuracy critical exponents for O(N) hierarchical 3D sigma models

    International Nuclear Information System (INIS)

    Godina, J. J.; Li, L.; Meurice, Y.; Oktay, M. B.

    2006-01-01

    The critical exponent γ and its subleading exponent Δ in the 3D O(N) Dyson's hierarchical model for N up to 20 are calculated with high accuracy. We calculate the critical temperatures for the measure δ(φ-vector.φ-vector-1). We extract the first coefficients of the 1/N expansion from our numerical data. We show that the leading and subleading exponents agree with Polchinski equation and the equivalent Litim equation, in the local potential approximation, with at least 4 significant digits

  4. Types of work-family interface: well-being correlates of negative and positive spillover between work and family

    NARCIS (Netherlands)

    Kinnunen, U.; Feldt, T.; Geurts, S.A.E.; Pulkkinen, L.

    2006-01-01

    The aim of the present study was to test the structure of the work-family interface measure, which was intended to take into account both the positive and negative spillover between work and family demands in both directions. In addition, the links among the types of work-family spillover and the

  5. A family of stadium-like billiards with parabolic boundaries under scaling analysis

    International Nuclear Information System (INIS)

    Livorati, Andre L P; Loskutov, Alexander; Leonel, Edson D

    2011-01-01

    Some chaotic properties of a family of stadium-like billiards with parabolic focusing components, which is described by a two-dimensional nonlinear area-preserving map, are studied. Critical values of billiard geometric parameters corresponding to a sudden change of the maximal Lyapunov exponent are found. It is shown that the maximal Lyapunov exponent obtained for chaotic orbits of this family is scaling invariant with respect to the control parameters describing the geometry of the billiard. We also show that this behavior is observed for a generic one-parameter family of mapping with the nonlinearity given by a tangent function.

  6. Analytic Quasi-Perodic Cocycles with Singularities and the Lyapunov Exponent of Extended Harper's Model

    Science.gov (United States)

    Jitomirskaya, S.; Marx, C. A.

    2012-11-01

    We show how to extend (and with what limitations) Avila's global theory of analytic SL(2,C) cocycles to families of cocycles with singularities. This allows us to develop a strategy to determine the Lyapunov exponent for the extended Harper's model, for all values of parameters and all irrational frequencies. In particular, this includes the self-dual regime for which even heuristic results did not previously exist in physics literature. The extension of Avila's global theory is also shown to imply continuous behavior of the LE on the space of analytic {M_2({C})}-cocycles. This includes rational approximation of the frequency, which so far has not been available.

  7. Behaviour of Lyapunov exponents near crisis points in the dissipative standard map

    Science.gov (United States)

    Pompe, B.; Leven, R. W.

    1988-11-01

    We numerically study the behaviour of the largest Lyapunov characteristic exponent λ1 in dependence on a control parameter in the 2D standard map with dissipation. In order to investigate the system's motion in parameter intervals slightly above crisis points we introduce "partial" Lyapunov exponents which characterize the average exponential divergence of nearby orbits on a semi-attractor at a boundary crisis and on distinct parts of a "large" chaotic attractor near an interior crisis. In the former case we find no significant difference between λ1 in the pre-crisis regime and the partial Lyapunov exponent describing transient chaotic motions slightly above the crisis. For the latter case we give a quantitative description of the drastic increase of λ1. Moreover, a formula which connects the critical exponent of a chaotic transient above a boundary crisis with a pointwise dimension is derived.

  8. Intermittency exponent of the turbulent energy cascade

    International Nuclear Information System (INIS)

    Cleve, J.; Greiner, M.; Pearson, B.R.; Sreenivasan, K.R.

    2006-12-01

    We consider the turbulent energy dissipation from one-dimensional records in experiments using air and gaseous helium at cryogenic temperatures, and obtain the intermittency exponent via the two-point correlation function of the energy dissipation. The air data are obtained in a number of flows in a wind tunnel and the atmospheric boundary layer at a height of about 35 m above the ground. The helium data correspond to the centerline of a jet exhausting into a container. The air data on the intermittency exponent are consistent with each other and with a trend that increases with the Taylor microscale Reynolds number, R λ , of up to about 1000 and saturates thereafter. On the other hand, the helium data cluster around a constant value at nearly all R λ , this being about half of the asymptotic value for the air data. Some possible explanation is offered for this anomaly. (author)

  9. Some existence results for a fourth order equation involving critical exponent

    CERN Document Server

    Ben-Ayed, M; Hammami, M

    2003-01-01

    In this paper a fourth order equation involving critical growth is considered under the Navier boundary condition: DELTA sup 2 u = Ku sup p , u > 0 in OMEGA, u = DELTA u = 0 on partial deriv OMEGA, where K is a positive function, OMEGA is a bounded smooth domain in R sup n , n >= 5 and p + 1 2n/(n - 4) is the critical Sobolev exponent. We give some topological conditions on K to ensure the existence of solutions. Our methods involve the study of the critical points at infinity and their contribution to the topology of the level sets of the associated Euler Lagrange functional.

  10. The anomalous scaling exponents of turbulence in general dimension from random geometry

    Energy Technology Data Exchange (ETDEWEB)

    Eling, Christopher [Rudolf Peierls Centre for Theoretical Physics, University of Oxford, 1 Keble Road, Oxford OX1 3NP (United Kingdom); Oz, Yaron [Raymond and Beverly Sackler School of Physics and Astronomy, Tel Aviv University, Tel Aviv 69978 (Israel)

    2015-09-22

    We propose an analytical formula for the anomalous scaling exponents of inertial range structure functions in incompressible fluid turbulence. The formula is a Knizhnik-Polyakov-Zamolodchikov (KPZ)-type relation and is valid in any number of space dimensions. It incorporates intermittency in a novel way by dressing the Kolmogorov linear scaling via a coupling to a lognormal random geometry. The formula has one real parameter γ that depends on the number of space dimensions. The scaling exponents satisfy the convexity inequality, and the supersonic bound constraint. They agree with the experimental and numerical data in two and three space dimensions, and with numerical data in four space dimensions. Intermittency increases with γ, and in the infinite γ limit the scaling exponents approach the value one, as in Burgers turbulence. At large n the nth order exponent scales as √n. We discuss the relation between fluid flows and black hole geometry that inspired our proposal.

  11. Nature of exponents found in the critical regime of YBCO

    International Nuclear Information System (INIS)

    Marhas, Manmeet Kaur; Saravanan, P.; Balakrishnan, K.; Srinivasan, R.; Kanjilal, D.; Metha, G.K.; Pai, S.P.; Pinto, R.; Vedvyas, M.; Ogale, S.B.; Mohan Rao, G.; Nathan, Senthil; Mohan, S.

    1997-01-01

    Full text: Fluctuation effects in electrical conductivity near T c is an important tool for studying the nature of phase transition in high T c ceramics. Probing critical regime by way of experiments demand data of good precision. Measurements were carried out on well characterised high T c films prepared by laser ablation and high pressure oxygen sputtering. High energy ion irradiation carried out to see the effect of disorder. Precise electrical resistivity measurements were carried out near T c with a temperature control accuracy better than 10 mK and large number of data points were collected in this regime. 100 MeV oxygen and 200 MeV Ag ions were used with varying fluences for irradiation at 77K. The data was analysed using existing models of critical fluctuation effects. The exponent of electrical conductivity in laser ablated thin films whose transition widths are less than 1 K was 1.33 and is independent of disorder caused by high energy ion irradiation and this could be identified as the exponent for excess conductivity in the critical intermediate charged fluctuation regime as proposed by Fisher. The exponent is around 2.7 in those films whose transition widths are greater than 1 K and also was independent of disorder and this could be identified as exponent in the para coherence regime

  12. Scaling exponents for fracture surfaces in opal glass

    Energy Technology Data Exchange (ETDEWEB)

    Chavez-Guerrero, L., E-mail: guerreroleo@hotmail.com [Facultad de Ingenieria Mecanica y Electrica. Cd. Universitaria s/n, C.P. 66450, Universidad Autonoma de Nuevo Leon, Nuevo Leon (Mexico); Center of Innovation, Research and Development on Engineering and Technology, Universidad Autonoma de Nuevo Leon Monterrey, C.P. 66600, Apodaca, Nuevo Leon (Mexico); Garza, F.J., E-mail: fjgarza@gama.fime.uanl.mx [Facultad de Ciencias Quimicas, Cd. Universitaria s/n, C.P. 66450, Universidad Autonoma de Nuevo Leon, Nuevo Leon (Mexico); Hinojosa, M., E-mail: hinojosa@gama.fime.uanl.mx [Facultad de Ingenieria Mecanica y Electrica. Cd. Universitaria s/n, C.P. 66450, Universidad Autonoma de Nuevo Leon, Nuevo Leon (Mexico); Center of Innovation, Research and Development on Engineering and Technology, Universidad Autonoma de Nuevo Leon Monterrey, C.P. 66600, Apodaca, Nuevo Leon (Mexico)

    2010-09-25

    We have investigated the scaling properties of fracture surfaces in opal glass. Specimens with two different opacifying particle sizes (1 {mu}m and 0.4 {mu}m) were broken by three-point bending test and the resulting fracture surfaces were analyzed using Atomic Force Microscopy. The analysis of the self-affine behavior was performed using the Variable Bandwidth and Height-Height Correlation Methods, and both the roughness exponent, {zeta}, and the correlation length, {xi}, were determined. It was found that the roughness exponent obtained in both samples is {zeta} {approx} 0.8; whereas the correlation length in both fractures is of the order of the particle size, demonstrating the dependence of this self-affine parameter on the microstructure of opal glass.

  13. Scaling exponents for fracture surfaces in opal glass

    International Nuclear Information System (INIS)

    Chavez-Guerrero, L.; Garza, F.J.; Hinojosa, M.

    2010-01-01

    We have investigated the scaling properties of fracture surfaces in opal glass. Specimens with two different opacifying particle sizes (1 μm and 0.4 μm) were broken by three-point bending test and the resulting fracture surfaces were analyzed using Atomic Force Microscopy. The analysis of the self-affine behavior was performed using the Variable Bandwidth and Height-Height Correlation Methods, and both the roughness exponent, ζ, and the correlation length, ξ, were determined. It was found that the roughness exponent obtained in both samples is ζ ∼ 0.8; whereas the correlation length in both fractures is of the order of the particle size, demonstrating the dependence of this self-affine parameter on the microstructure of opal glass.

  14. Determination of critical exponents of inhomogeneous Gd films

    Energy Technology Data Exchange (ETDEWEB)

    Rosales-Rivera, A., E-mail: arosalesr@unal.edu.co [Laboratorio de Magnetismo y Materiales Avanzados, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Colombia, Sede Manizales, Manizales (Colombia); Salazar, N.A. [Laboratorio de Magnetismo y Materiales Avanzados, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Colombia, Sede Manizales, Manizales (Colombia); Hovorka, O.; Idigoras, O.; Berger, A. [CIC nanoGUNE Consolider, Tolosa Hiribidea 76, E-20018 Donostia-San Sebastian (Spain)

    2012-08-15

    The role of inhomogeneity on the critical behavior is studied for non-epitaxial Gd films. For this purpose, the film inhomogeneity was varied experimentally by annealing otherwise identical samples at different temperatures T{sub AN}=200, 400, and 500 Degree-Sign C. Vibrating sample magnetometry (VSM) was used for magnetization M vs. T measurements at different external fields H. A method based upon the linear superposition of different sample parts having different Curie temperatures T{sub C} was used to extract the critical exponents and the intrinsic distribution of Curie temperatures. We found that this method allows extracting reliable values of the critical exponents for all annealing temperatures, which enabled us to study the effects of disorder onto the universality class of Gd films.

  15. Determination of critical exponents of inhomogeneous Gd films

    International Nuclear Information System (INIS)

    Rosales-Rivera, A.; Salazar, N.A.; Hovorka, O.; Idigoras, O.; Berger, A.

    2012-01-01

    The role of inhomogeneity on the critical behavior is studied for non-epitaxial Gd films. For this purpose, the film inhomogeneity was varied experimentally by annealing otherwise identical samples at different temperatures T AN =200, 400, and 500 °C. Vibrating sample magnetometry (VSM) was used for magnetization M vs. T measurements at different external fields H. A method based upon the linear superposition of different sample parts having different Curie temperatures T C was used to extract the critical exponents and the intrinsic distribution of Curie temperatures. We found that this method allows extracting reliable values of the critical exponents for all annealing temperatures, which enabled us to study the effects of disorder onto the universality class of Gd films.

  16. PHYSIOLOGICAL RESPONSES DURING MATCHES AND PROFILE OF ELITE PENCAK SILAT EXPONENTS

    Directory of Open Access Journals (Sweden)

    Benedict Tan

    2002-12-01

    Full Text Available This is a descriptive, cross-sectional study describing the physiological responses during competitive matches and profile of elite exponents of an emerging martial art sport, pencak silat. Thirty exponents (21 males and 9 females were involved in the study. Match responses (i.e. heart rate (HR throughout match and capillary blood lactate concentration, [La], at pre-match and at the end of every round were obtained during actual competitive duels. Elite silat exponents' physiological attributes were assessed via anthropometry, vertical jump, isometric grip strength, maximal oxygen uptake, and the Wingate 30 s anaerobic test of the upper and lower body, in the laboratory. The match response data showed that silat competitors' mean HR was > 84% of estimated HR maximum and levels of [La] ranged from 6.7 - 18.7 mMol-1 during matches. This suggests that competitive silat matches are characterised by high aerobic and anaerobic responses. In comparison to elite taekwondo and judo athletes' physiological characteristics, elite silat exponents have lower aerobic fitness and grip strength, but greater explosive leg power (vertical jump. Generally, they also possessed a similar anaerobic capability in the lower but markedly inferior anaerobic capability in the upper body

  17. Quantum computation of multifractal exponents through the quantum wavelet transform

    International Nuclear Information System (INIS)

    Garcia-Mata, Ignacio; Giraud, Olivier; Georgeot, Bertrand

    2009-01-01

    We study the use of the quantum wavelet transform to extract efficiently information about the multifractal exponents for multifractal quantum states. We show that, combined with quantum simulation algorithms, it enables to build quantum algorithms for multifractal exponents with a polynomial gain compared to classical simulations. Numerical results indicate that a rough estimate of fractality could be obtained exponentially fast. Our findings are relevant, e.g., for quantum simulations of multifractal quantum maps and of the Anderson model at the metal-insulator transition.

  18. Thickness dependence of effective critical exponents in three-dimensional Ising plates

    International Nuclear Information System (INIS)

    Marques, M.I.; Gonzalo, J.A.

    2000-01-01

    Phase transitions in ising plates of equal area and different thickness have been studied by the Monte Carlo approach. The evolution of the critical temperature and of the effective critical exponents with the thickness of the lattice has been numerically determined. The thickness dependence of the maximum value of the effective critical exponents is well described by an exponential decay towards the respective three-dimensional value. (author)

  19. Questions never asked. Positive family outcomes of extremely premature childbirth

    DEFF Research Database (Denmark)

    Lou, Hanne; Pedersen, Birthe D; Hedegaard, Morten

    2009-01-01

    OBJECTIVE: To explore positive aspects of family life after extremely premature childbirth, thereby supplementing current literature on long-term family outcome. DESIGN: Semi-structured, qualitative research interviews were analysed according to the editing strategy described by Miller and Crabtree....... SETTING: Denmark, Europe. PARTICIPANTS: Nine fathers and 11 mothers of 14 children born before 28 completed weeks of gestation at a tertiary centre were interviewed when their children were 7-10 years old. RESULTS: Whereas developmental delay, functional limitations, family burden, and parental distress...

  20. New relation for critical exponents in the Ising model

    International Nuclear Information System (INIS)

    Pishtshev, A.

    2007-01-01

    The Ising model in a transverse field is considered at T=0. From the analysis of the power low behaviors of the energy gap and the order parameter as functions of the field a new relation between the respective critical exponents, β>=1/(8s 2 ), is derived. By using the Suzuki equivalence from this inequality a new relation for critical exponents in the Ising model, β>=1/(8ν 2 ), is obtained. A number of numerical examples for different cases illustrates the generality and validity of the relation. By applying this relation the estimation ν=(1/4) 1/3 ∼0.62996 for the 3D-Ising model is proposed

  1. Critical exponents for the Reggeon quantum spin model

    International Nuclear Information System (INIS)

    Brower, R.C.; Furman, M.A.

    1978-01-01

    The Reggeon quantum spin (RQS) model on the transverse lattice in D dimensional impact parameter space has been conjectured to have the same critical behaviour as the Reggeon field theory (RFT). Thus from a high 'temperature' series of ten (D=2) and twenty (D=1) terms for the RQS model the authors extrapolate to the critical temperature T=Tsub(c) by Pade approximants to obtain the exponents eta=0.238 +- 0.008, z=1.16 +- 0.01, γ=1.271 +- 0.007 for D=2 and eta=0.317 +- 0.002, z=1.272 +- 0.007, γ=1.736 +- 0.001, lambda=0.57 +- 0.03 for D=1. These exponents naturally interpolate between the D=0 and D=4-epsilon results for RFT as expected on the basis of the universality conjecture. (Auth.)

  2. Monte Carlo-Based Tail Exponent Estimator

    Czech Academy of Sciences Publication Activity Database

    Baruník, Jozef; Vácha, Lukáš

    2010-01-01

    Roč. 2010, č. 6 (2010), s. 1-26 R&D Projects: GA ČR GA402/09/0965; GA ČR GD402/09/H045; GA ČR GP402/08/P207 Institutional research plan: CEZ:AV0Z10750506 Keywords : Hill estimator * α-stable distributions * tail exponent estimation Subject RIV: AH - Economics http://library.utia.cas.cz/separaty/2010/E/barunik-0342493.pdf

  3. A new combined approach on Hurst exponent estimate and its applications in realized volatility

    Science.gov (United States)

    Luo, Yi; Huang, Yirong

    2018-02-01

    The purpose of this paper is to propose a new estimator of Hurst exponent based on the combined information of the conventional rescaled range methods. We demonstrate the superiority of the proposed estimator by Monte Carlo simulations, and the applications in estimating the Hurst exponent of daily volatility series in Chinese stock market. Moreover, we indicate the impact of the type of estimator and structural break on the estimating results of Hurst exponent.

  4. Lyapunov exponent of the random frequency oscillator: cumulant expansion approach

    International Nuclear Information System (INIS)

    Anteneodo, C; Vallejos, R O

    2010-01-01

    We consider a one-dimensional harmonic oscillator with a random frequency, focusing on both the standard and the generalized Lyapunov exponents, λ and λ* respectively. We discuss the numerical difficulties that arise in the numerical calculation of λ* in the case of strong intermittency. When the frequency corresponds to a Ornstein-Uhlenbeck process, we compute analytically λ* by using a cumulant expansion including up to the fourth order. Connections with the problem of finding an analytical estimate for the largest Lyapunov exponent of a many-body system with smooth interactions are discussed.

  5. On some properties of the discrete Lyapunov exponent

    International Nuclear Information System (INIS)

    Amigo, Jose M.; Kocarev, Ljupco; Szczepanski, Janusz

    2008-01-01

    One of the possible by-products of discrete chaos is the application of its tools, in particular of the discrete Lyapunov exponent, to cryptography. In this Letter we explore this question in a very general setting

  6. Positive Eigenvalues of Generalized Words in Two Hermitian Positive Definite Matrices

    OpenAIRE

    Hillar, Christopher; Johnson, Charles R.

    2005-01-01

    We define a word in two positive definite (complex Hermitian) matrices $A$ and $B$ as a finite product of real powers of $A$ and $B$. The question of which words have only positive eigenvalues is addressed. This question was raised some time ago in connection with a long-standing problem in theoretical physics, and it was previously approached by the authors for words in two real positive definite matrices with positive integral exponents. A large class of words that do guarantee positive eig...

  7. Lojasiewicz exponents and Newton polyhedra

    International Nuclear Information System (INIS)

    Pham Tien Son

    2006-07-01

    In this paper we obtain the exact value of the Lojasiewicz exponent at the origin of analytic map germs on K n (K = R or C under the Newton non-degeneracy condition, using information from their Newton polyhedra. We also give some conclusions on Newton non-degenerate analytic map germs. As a consequence, we obtain a link between Newton non-degenerate ideals and their integral closures, thus leading to a simple proof of a result of Saia. Similar results are also considered to polynomial maps which are Newton non-degenerate at infinity. (author)

  8. Critical exponents predicted by grouping of Feynman diagrams in φ4 model

    International Nuclear Information System (INIS)

    Kaupuzs, J.

    2001-01-01

    Different perturbation theory treatments of the Ginzburg-Landau phase transition model are discussed. This includes a criticism of the perturbative renormalization group (RG) approach and a proposal of a novel method providing critical exponents consistent with the known exact solutions in two dimensions. The usual perturbation theory is reorganized by appropriate grouping of Feynman diagrams of φ 4 model with O(n) symmetry. As a result, equations for calculation of the two-point correlation function are obtained which allow to predict possible exact values of critical exponents in two and three dimensions by proving relevant scaling properties of the asymptotic solution at (and near) the criticality. The new values of critical exponents are discussed and compared to the results of numerical simulations and experiments. (orig.)

  9. Inter-relationship between scaling exponents for describing self-similar river networks

    Science.gov (United States)

    Yang, Soohyun; Paik, Kyungrock

    2015-04-01

    Natural river networks show well-known self-similar characteristics. Such characteristics are represented by various power-law relationships, e.g., between upstream length and drainage area (exponent h) (Hack, 1957), and in the exceedance probability distribution of upstream area (exponent ɛ) (Rodriguez-Iturbe et al., 1992). It is empirically revealed that these power-law exponents are within narrow ranges. Power-law is also found in the relationship between drainage density (the total stream length divided by the total basin area) and specified source area (the minimum drainage area to form a stream head) (exponent η) (Moussa and Bocquillon, 1996). Considering that above three scaling relationships all refer to fundamental measures of 'length' and 'area' of a given drainage basin, it is natural to hypothesize plausible inter-relationship between these three scaling exponents. Indeed, Rigon et al. (1996) demonstrated the relationship between ɛ and h. In this study, we expand this to a more general ɛ-η-h relationship. We approach ɛ-η relationship in an analytical manner while η-h relationship is demonstrated for six study basins in Korea. Detailed analysis and implications will be presented. References Hack, J. T. (1957). Studies of longitudinal river profiles in Virginia and Maryland. US, Geological Survey Professional Paper, 294. Moussa, R., & Bocquillon, C. (1996). Fractal analyses of tree-like channel networks from digital elevation model data. Journal of Hydrology, 187(1), 157-172. Rigon, R., Rodriguez-Iturbe, I., Maritan, A., Giacometti. A., Tarboton, D. G., & Rinaldo, A. (1996). On Hack's Law. Water Resources Research, 32(11), 3367-3374. Rodríguez-Iturbe, I., Ijjasz-Vasquez, E. J., Bras, R. L., & Tarboton, D. G. (1992). Power law distributions of discharge mass and energy in river basins. Water Resources Research, 28(4), 1089-1093.

  10. Evaluation of significance of positive familial history in prevalence of hypertension in Isfahan

    Directory of Open Access Journals (Sweden)

    Tavassoli A

    1997-09-01

    Full Text Available Hypertension is one of the most important modifiable risk factors of vascular heart disease. Control of hypertension in different age groups has a significant effect upon the control and prevention of vascular heart disease. A familial pattern is observed in the distribution of blood pressure in different societies. Family history of hypertension has a profound effect on the future risk of developing hypertension. The blood pressure of approximately 8150 inhabitants of Isfahan aged above 18 years was measured during 1993-94. Blood pressure measurements were performed according to the standards set by WHO i.e., on two separate occasions, in the sitting position, and from both arms. A questionnaire was completed consisting of 26 questions, including questions regarding history of hypertension in first and second-degree relatives. Cases with a blood pressure of 140/90 mmHg or more, were referred to the Cardiovascular Research Center of Isfahan for further evaluation. Mean systolic and diastolic blood pressure was higher in cases with a positive family history of hypertension. In this study, 37.4% of the men with hypertension and 45.4% of hypertensive women had positive history of hypertension in first-degree relatives. The association between positive family history and hypertension was not significant in men (P=0.62, but it was significant in women (P=0.000. This difference was less pronounced in the older age groups, which could be explained by the illiteracy of most of the older cases and their ignorance of the existence of hypertension in family members. After correcting for the effects of confounding factors, it appears that positive family history has a stronger association with the development of hypertension in women. Moreover, positive family history is a strong prognostic factor in the likelihood of hypertension in the children of affected cases. These findings emphasize the importance of routine blood pressure measurement in children and

  11. On identifying relationships between the flood scaling exponent and basin attributes.

    Science.gov (United States)

    Medhi, Hemanta; Tripathi, Shivam

    2015-07-01

    Floods are known to exhibit self-similarity and follow scaling laws that form the basis of regional flood frequency analysis. However, the relationship between basin attributes and the scaling behavior of floods is still not fully understood. Identifying these relationships is essential for drawing connections between hydrological processes in a basin and the flood response of the basin. The existing studies mostly rely on simulation models to draw these connections. This paper proposes a new methodology that draws connections between basin attributes and the flood scaling exponents by using observed data. In the proposed methodology, region-of-influence approach is used to delineate homogeneous regions for each gaging station. Ordinary least squares regression is then applied to estimate flood scaling exponents for each homogeneous region, and finally stepwise regression is used to identify basin attributes that affect flood scaling exponents. The effectiveness of the proposed methodology is tested by applying it to data from river basins in the United States. The results suggest that flood scaling exponent is small for regions having (i) large abstractions from precipitation in the form of large soil moisture storages and high evapotranspiration losses, and (ii) large fractions of overland flow compared to base flow, i.e., regions having fast-responding basins. Analysis of simple scaling and multiscaling of floods showed evidence of simple scaling for regions in which the snowfall dominates the total precipitation.

  12. Stochastic model of Zipf's law and the universality of the power-law exponent.

    Science.gov (United States)

    Yamamoto, Ken

    2014-04-01

    We propose a stochastic model of Zipf's law, namely a power-law relation between rank and size, and clarify as to why a specific value of its power-law exponent is quite universal. We focus on the successive total of a multiplicative stochastic process. By employing properties of a well-known stochastic process, we concisely show that the successive total follows a stationary power-law distribution, which is directly related to Zipf's law. The formula of the power-law exponent is also derived. Finally, we conclude that the universality of the rank-size exponent is brought about by symmetry between an increase and a decrease in the random growth rate.

  13. Positive parenting in ethnic minority families : challenges and outcomes

    NARCIS (Netherlands)

    Emmen, Rosalia Antonia Grada (Rosanneke)

    2014-01-01

    The overall goal of the current dissertation is to uncover predictors and outcomes of positive parenting in ethnic minority families. Chapter 2 provides an overview of commonly used observational instruments to measure sensitivity, showing the versatility and scientific importance of the construct.

  14. Lyapunov exponents a tool to explore complex dynamics

    CERN Document Server

    Pikovsky, Arkady

    2016-01-01

    Lyapunov exponents lie at the heart of chaos theory, and are widely used in studies of complex dynamics. Utilising a pragmatic, physical approach, this self-contained book provides a comprehensive description of the concept. Beginning with the basic properties and numerical methods, it then guides readers through to the most recent advances in applications to complex systems. Practical algorithms are thoroughly reviewed and their performance is discussed, while a broad set of examples illustrate the wide range of potential applications. The description of various numerical and analytical techniques for the computation of Lyapunov exponents offers an extensive array of tools for the characterization of phenomena such as synchronization, weak and global chaos in low and high-dimensional set-ups, and localization. This text equips readers with all the investigative expertise needed to fully explore the dynamical properties of complex systems, making it ideal for both graduate students and experienced researchers...

  15. On generalized scaling laws with continuously varying exponents

    International Nuclear Information System (INIS)

    Sittler, Lionel; Hinrichsen, Haye

    2002-01-01

    Many physical systems share the property of scale invariance. Most of them show ordinary power-law scaling, where quantities can be expressed as a leading power law times a scaling function which depends on scaling-invariant ratios of the parameters. However, some systems do not obey power-law scaling, instead there is numerical evidence for a logarithmic scaling form, in which the scaling function depends on ratios of the logarithms of the parameters. Based on previous ideas by Tang we propose that this type of logarithmic scaling can be explained by a concept of local scaling invariance with continuously varying exponents. The functional dependence of the exponents is constrained by a homomorphism which can be expressed as a set of partial differential equations. Solving these equations we obtain logarithmic scaling as a special case. The other solutions lead to scaling forms where logarithmic and power-law scaling are mixed

  16. The Multivariate Largest Lyapunov Exponent as an Age-Related Metric of Quiet Standing Balance

    Directory of Open Access Journals (Sweden)

    Kun Liu

    2015-01-01

    Full Text Available The largest Lyapunov exponent has been researched as a metric of the balance ability during human quiet standing. However, the sensitivity and accuracy of this measurement method are not good enough for clinical use. The present research proposes a metric of the human body’s standing balance ability based on the multivariate largest Lyapunov exponent which can quantify the human standing balance. The dynamic multivariate time series of ankle, knee, and hip were measured by multiple electrical goniometers. Thirty-six normal people of different ages participated in the test. With acquired data, the multivariate largest Lyapunov exponent was calculated. Finally, the results of the proposed approach were analysed and compared with the traditional method, for which the largest Lyapunov exponent and power spectral density from the centre of pressure were also calculated. The following conclusions can be obtained. The multivariate largest Lyapunov exponent has a higher degree of differentiation in differentiating balance in eyes-closed conditions. The MLLE value reflects the overall coordination between multisegment movements. Individuals of different ages can be distinguished by their MLLE values. The standing stability of human is reduced with the increment of age.

  17. Work-Family facilitation: a positive psychological perspective on role combination

    OpenAIRE

    Steenbergen, Elianne Florence van

    2007-01-01

    This dissertation provides a balanced picture of the experiences that individuals can have in the combination of their work and family roles. Extending the common focus in previous literature on experiences of role conflict (and their detrimental consequences), the present research also addresses the positive side of role combination and reveals the different ways in which work and family roles can facilitate each other (energy-based, time-based, behavioral, and psychological facilitation). T...

  18. Identification of exponent from load-deformation relation for soft materials from impact tests

    Science.gov (United States)

    Ciornei, F. C.; Alaci, S.; Romanu, I. C.; Ciornei, M. C.; Sopon, G.

    2018-01-01

    When two bodies are brought into contact, the magnitude of occurring reaction forces increase together with the amplitude of deformations. The load-deformation dependency of two contacting bodies is described by a function having the form F = Cxα . An accurate illustration of this relationship assumes finding the precise coefficient C and exponent α. This representation proved to be very useful in hardness tests, in dynamic systems modelling or in considerations upon the elastic-plastic ratio concerning a Hertzian contact. The classical method for identification of the exponent consists in finding it from quasi-static tests. The drawback of the method is the fact that the accurate estimation of the exponent supposes precise identification of the instant of contact initiation. To overcome this aspect, the following observation is exploited: during an impact process, the dissipated energy is converted into heat released by internal friction in the materials and energy for plastic deformations. The paper is based on the remark that for soft materials the hysteresis curves obtained for a static case are similar to the ones obtained for medium velocities. Furthermore, utilizing the fact that for the restitution phase the load-deformation dependency is elastic, a method for finding the α exponent for compression phase is proposed. The maximum depth of the plastic deformations obtained for a series of collisions, by launching, from different heights, a steel ball in free falling on an immobile prism made of soft material, is evaluated by laser profilometry method. The condition that the area of the hysteresis loop equals the variation of kinetical energy of the ball is imposed and two tests are required for finding the exponent. Five collisions from different launching heights of the ball were taken into account. For all the possible impact-pair cases, the values of the exponent were found and close values were obtained.

  19. Effect of density of state on isotope effect exponent of two-band superconductors

    International Nuclear Information System (INIS)

    Udomsamuthirun, P.; Kumvongsa, C.; Burakorn, A.; Changkanarth, P.; Yoksan, S.

    2005-01-01

    The exact formula of T c 's equation and the isotope effect exponent of two-band s-wave superconductors in weak-coupling limit are derived by considering the influence of two kinds of density of state: constant and van Hove singularity. The paring interaction in each band consisted of two parts: the electron-phonon interaction and non-electron-phonon interaction are included in our model. We find that the interband interaction of electron-phonon show more effect on isotope exponent than the intraband interaction and the isotope effect exponent with constant density of state can fit to experimental data, MgB 2 and high-T c superconductor, better than van Hove singularity density of state

  20. Family environment and adult resilience: contributions of positive parenting and the oxytocin receptor gene

    Directory of Open Access Journals (Sweden)

    Bekh Bradley

    2013-09-01

    Full Text Available Background: Abundant research shows that childhood adversity increases the risk for adult psychopathology while research on influences of positive family environment on risk for psychopathology is limited. Similarly, a growing body of research examines genetic and gene by environment predictors of psychopathology, yet such research on predictors of resilience is sparse. Objectives: We examined the role of positive factors in childhood family environment (CFE and the OXTR rs53576 genotype in predicting levels of adult resilient coping and positive affect. We also examined whether the relationship between positive factors in the CFEs and adult resilient coping and positive affect varied across OXTR rs53576 genotype. Methods: We gathered self-report data on childhood environment, trauma history, and adult resilience and positive affect in a sample of 971 African American adults. Results: We found that positive CFE was positively associated with higher levels of resilient coping and positive affect in adulthood after controlling for childhood maltreatment, other trauma, and symptoms of posttraumatic stress disorder. We did not find a direct effect of OXTR 53576 on a combined resilient coping/positive-affect-dependent variable, but we did find an interaction of OXTR rs53576 with family environment. Conclusions: Our data suggest that even in the face of adversity, positive aspects of the family environment may contribute to resilience. These results highlight the importance of considering protective developmental experiences and the interaction of such experiences with genetic variants in risk and resilience research.For the abstract or full text in other languages, please see Supplementary files under Article Tools online

  1. Fertility desire and family-planning demand among HIV-positive ...

    African Journals Online (AJOL)

    Little information exists about desire to have children and family-planning use among HIV-positive individuals and how this may vary according to individual, social, health and demographic characteristics, especially in developing countries. To assess these topics in Ethiopia, a facility-based cross-sectional study was ...

  2. Estimation of Hurst Exponent for the Financial Time Series

    Science.gov (United States)

    Kumar, J.; Manchanda, P.

    2009-07-01

    Till recently statistical methods and Fourier analysis were employed to study fluctuations in stock markets in general and Indian stock market in particular. However current trend is to apply the concepts of wavelet methodology and Hurst exponent, see for example the work of Manchanda, J. Kumar and Siddiqi, Journal of the Frankline Institute 144 (2007), 613-636 and paper of Cajueiro and B. M. Tabak. Cajueiro and Tabak, Physica A, 2003, have checked the efficiency of emerging markets by computing Hurst component over a time window of 4 years of data. Our goal in the present paper is to understand the dynamics of the Indian stock market. We look for the persistency in the stock market through Hurst exponent and fractal dimension of time series data of BSE 100 and NIFTY 50.

  3. Power-law Exponent in Multiplicative Langevin Equation with Temporally Correlated Noise

    Science.gov (United States)

    Morita, Satoru

    2018-05-01

    Power-law distributions are ubiquitous in nature. Random multiplicative processes are a basic model for the generation of power-law distributions. For discrete-time systems, the power-law exponent is known to decrease as the autocorrelation time of the multiplier increases. However, for continuous-time systems, it is not yet clear how the temporal correlation affects the power-law behavior. Herein, we analytically investigated a multiplicative Langevin equation with colored noise. We show that the power-law exponent depends on the details of the multiplicative noise, in contrast to the case of discrete-time systems.

  4. On the relation between Lyapunov exponents and exponential decay of correlations

    International Nuclear Information System (INIS)

    Slipantschuk, Julia; Bandtlow, Oscar F; Just, Wolfram

    2013-01-01

    Chaotic dynamics with sensitive dependence on initial conditions may result in exponential decay of correlation functions. We show that for one-dimensional interval maps the corresponding quantities, that is, Lyapunov exponents and exponential decay rates, are related. More specifically, for piecewise linear expanding Markov maps observed via piecewise analytic functions, we show that the decay rate is bounded above by twice the Lyapunov exponent, that is, we establish lower bounds for the subleading eigenvalue of the corresponding Perron–Frobenius operator. In addition, we comment on similar relations for general piecewise smooth expanding maps. (paper)

  5. Controversy in the allometric application of fixed- versus varying-exponent models: a statistical and mathematical perspective.

    Science.gov (United States)

    Tang, Huadong; Hussain, Azher; Leal, Mauricio; Fluhler, Eric; Mayersohn, Michael

    2011-02-01

    This commentary is a reply to a recent article by Mahmood commenting on the authors' article on the use of fixed-exponent allometry in predicting human clearance. The commentary discusses eight issues that are related to criticisms made in Mahmood's article and examines the controversies (fixed-exponent vs. varying-exponent allometry) from the perspective of statistics and mathematics. The key conclusion is that any allometric method, which is to establish a power function based on a limited number of animal species and to extrapolate the resulting power function to human values (varying-exponent allometry), is infused with fundamental statistical errors. Copyright © 2010 Wiley-Liss, Inc.

  6. Landau-like theory for universality of critical exponents in quasistationary states of isolated mean-field systems.

    Science.gov (United States)

    Ogawa, Shun; Yamaguchi, Yoshiyuki Y

    2015-06-01

    An external force dynamically drives an isolated mean-field Hamiltonian system to a long-lasting quasistationary state, whose lifetime increases with population of the system. For second order phase transitions in quasistationary states, two nonclassical critical exponents have been reported individually by using a linear and a nonlinear response theories in a toy model. We provide a simple way to compute the critical exponents all at once, which is an analog of the Landau theory. The present theory extends the universality class of the nonclassical exponents to spatially periodic one-dimensional systems and shows that the exponents satisfy a classical scaling relation inevitably by using a key scaling of momentum.

  7. Critical exponents of extremal Kerr perturbations

    Science.gov (United States)

    Gralla, Samuel E.; Zimmerman, Peter

    2018-05-01

    We show that scalar, electromagnetic, and gravitational perturbations of extremal Kerr black holes are asymptotically self-similar under the near-horizon, late-time scaling symmetry of the background metric. This accounts for the Aretakis instability (growth of transverse derivatives) as a critical phenomenon associated with the emergent symmetry. We compute the critical exponent of each mode, which is equivalent to its decay rate. It follows from symmetry arguments that, despite the growth of transverse derivatives, all generally covariant scalar quantities decay to zero.

  8. Scaling exponent and dispersity of polymers in solution by diffusion NMR.

    Science.gov (United States)

    Williamson, Nathan H; Röding, Magnus; Miklavcic, Stanley J; Nydén, Magnus

    2017-05-01

    Molecular mass distribution measurements by pulsed gradient spin echo nuclear magnetic resonance (PGSE NMR) spectroscopy currently require prior knowledge of scaling parameters to convert from polymer self-diffusion coefficient to molecular mass. Reversing the problem, we utilize the scaling relation as prior knowledge to uncover the scaling exponent from within the PGSE data. Thus, the scaling exponent-a measure of polymer conformation and solvent quality-and the dispersity (M w /M n ) are obtainable from one simple PGSE experiment. The method utilizes constraints and parametric distribution models in a two-step fitting routine involving first the mass-weighted signal and second the number-weighted signal. The method is developed using lognormal and gamma distribution models and tested on experimental PGSE attenuation of the terminal methylene signal and on the sum of all methylene signals of polyethylene glycol in D 2 O. Scaling exponent and dispersity estimates agree with known values in the majority of instances, leading to the potential application of the method to polymers for which characterization is not possible with alternative techniques. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. High-resolution satellite image segmentation using Hölder exponents

    Indian Academy of Sciences (India)

    Keywords. High resolution image; texture analysis; segmentation; IKONOS; Hölder exponent; cluster. ... are that. • it can be used as a tool to measure the roughness ... uses reinforcement learning to learn the reward values of ..... The numerical.

  10. THE ADAPTATION OF THE QUESTIONNAIRE POSITIVE AND DESTRUCTIVE FAMILY

    Directory of Open Access Journals (Sweden)

    Ilona Skuja

    2013-12-01

    Full Text Available In order to be able to correct the asocial behaviour of adolescents, several factors that can have POSITIVE AND DESTRUCTIVE FAMILY an effect on the issue must be understood, these being biological, social, and psychological, as well as understanding the context of the situation itself. Various methods were used to research valuable adolescent family environments, including the questionnaire entitled Positive and Destructive Family, which was developed by Russian authors (Опросник “Конструктивно-деструктивная семья” (КДС, Эйдемиллер, Юстицкис. Since this methodology was not available to researchers in Latvian, the first step to be taken was to adapt this method to the cultural environment of Latvia. (The author’s consent has been received for the use of the questionnaire in scientific work. The adaptation of the method allows the following steps to be implemented (Hambleton & Patsula, 1998; 1999; 2000; Van de Vijver & Hambleton, 1996: the translation and backward translation of questionnaire observing the context of the cultural environment; empirical verification of the translated questionnaire, thereby establishing its reliability and validity in accordance with the psychometric indicators used to provide a validity check on the factors illustrated in the source survey; the administration of the survey in the new cultural environment; documentation showing the adaptation of the questionnaire and the development of the interpretation of the survey’s values. To date, only some of the aforementioned steps have been implemented and presented. Respondents from sixty families participated in the survey (all of whom were aged in group of 31-68, and who included 42 women and eighteen men. The survey consists of twenty statements to which respondents will reply either positively or negatively (this being the dichotomy scale. Further tasks are related to the complete adaptation and

  11. Estimation of time-dependent Hurst exponents with variational smoothing and application to forecasting foreign exchange rates

    Science.gov (United States)

    Garcin, Matthieu

    2017-10-01

    Hurst exponents depict the long memory of a time series. For human-dependent phenomena, as in finance, this feature may vary in the time. It justifies modelling dynamics by multifractional Brownian motions, which are consistent with time-dependent Hurst exponents. We improve the existing literature on estimating time-dependent Hurst exponents by proposing a smooth estimate obtained by variational calculus. This method is very general and not restricted to the sole Hurst framework. It is globally more accurate and easier than other existing non-parametric estimation techniques. Besides, in the field of Hurst exponents, it makes it possible to make forecasts based on the estimated multifractional Brownian motion. The application to high-frequency foreign exchange markets (GBP, CHF, SEK, USD, CAD, AUD, JPY, CNY and SGD, all against EUR) shows significantly good forecasts. When the Hurst exponent is higher than 0.5, what depicts a long-memory feature, the accuracy is higher.

  12. Positive psychology outcome measures for family caregivers of people living with dementia: a systematic review.

    Science.gov (United States)

    Stansfeld, Jacki; Stoner, Charlotte R; Wenborn, Jennifer; Vernooij-Dassen, Myrra; Moniz-Cook, Esme; Orrell, Martin

    2017-08-01

    Family caregivers of people living with dementia can have both positive and negative experiences of caregiving. Despite this, existing outcome measures predominately focus on negative aspects of caregiving such as burden and depression. This review aimed to evaluate the development and psychometric properties of existing positive psychology measures for family caregivers of people living with dementia to determine their potential utility in research and practice. A systematic review of positive psychology outcome measures for family caregivers of people with dementia was conducted. The databases searched were as follows: PsychINFO, CINAHL, MEDLINE, EMBASE, and PubMed. Scale development papers were subject to a quality assessment to appraise psychometric properties. Twelve positive outcome measures and six validation papers of these scales were identified. The emerging constructs of self-efficacy, spirituality, resilience, rewards, gain, and meaning are in line with positive psychology theory. There are some robust positive measures in existence for family caregivers of people living with dementia. However, lack of reporting of the psychometric properties hindered the quality assessment of some outcome measures identified in this review. Future research should aim to include positive outcome measures in interventional research to facilitate a greater understanding of the positive aspects of caregiving and how these contribute to well-being.

  13. Randomness confidence bands of fractal scaling exponents for financial price returns

    International Nuclear Information System (INIS)

    Ibarra-Valdez, C.; Alvarez, J.; Alvarez-Ramirez, J.

    2016-01-01

    Highlights: • A robust test for randomness of price returns is proposed. • The DFA scaling exponent is contrasted against confidence bands for random sequences. • The size of the band depends of the sequence length. • Crude oil and USA stock markets have been rarely inefficient. - Abstract: The weak-form of the efficient market hypothesis (EMH) establishes that price returns behave as a pure random process and so their outcomes cannot be forecasted. The detrended fluctuation analysis (DFA) has been widely used to test the weak-form of the EMH by showing that time series of price returns are serially uncorrelated. In this case, the DFA scaling exponent exhibits deviations from the theoretical value of 0.5. This work considers the test of the EMH for DFA implementation on a sliding window, which is an approach that is intended to monitor the evolution of markets. Under these conditions, the scaling exponent exhibits important variations over the scrutinized period that can offer valuable insights in the behavior of the market provided the estimated scaling value is kept within strict statistical tests to verify the presence or not of serial correlations in the price returns. In this work, the statistical tests are based on comparing the estimated scaling exponent with the values obtained from pure Gaussian sequences with the length of the real time series. In this way, the presence of serial correlations can be guaranteed only in terms of the confidence bands of a pure Gaussian process. The crude oil (WTI) and the USA stock (DJIA) markets are used to illustrate the methodology.

  14. Estimation of Spectral Exponent Parameter of 1/f Process in Additive White Background Noise

    Directory of Open Access Journals (Sweden)

    Semih Ergintav

    2007-01-01

    Full Text Available An extension to the wavelet-based method for the estimation of the spectral exponent, γ, in a 1/fγ process and in the presence of additive white noise is proposed. The approach is based on eliminating the effect of white noise by a simple difference operation constructed on the wavelet spectrum. The γ parameter is estimated as the slope of a linear function. It is shown by simulations that the proposed method gives reliable results. Global positioning system (GPS time-series noise is analyzed and the results provide experimental verification of the proposed method.

  15. Beyond Critical Exponents in Neuronal Avalanches

    Science.gov (United States)

    Friedman, Nir; Butler, Tom; Deville, Robert; Beggs, John; Dahmen, Karin

    2011-03-01

    Neurons form a complex network in the brain, where they interact with one another by firing electrical signals. Neurons firing can trigger other neurons to fire, potentially causing avalanches of activity in the network. In many cases these avalanches have been found to be scale independent, similar to critical phenomena in diverse systems such as magnets and earthquakes. We discuss models for neuronal activity that allow for the extraction of testable, statistical predictions. We compare these models to experimental results, and go beyond critical exponents.

  16. Magnetic entropy change and critical exponents in double perovskite Y2NiMnO6

    Science.gov (United States)

    Sharma, G.; Tripathi, T. S.; Saha, J.; Patnaik, S.

    2014-11-01

    We report the magnetic entropy change (ΔSM) and the critical exponents in the double perovskite manganite Y2NiMnO6 with a ferromagnetic to paramagnetic transition TC~85 K. For a magnetic field change ΔH=80 kOe, a maximum magnetic entropy change ΔSM=-6.57 J/kg K is recorded around TC. The critical exponents β=0.363±0.05 and γ=1.331±0.09 obtained from power law fitting to spontaneous magnetization MS(T) and the inverse initial susceptibility χ0-1(T) satisfy well to values derived for a 3D-Heisenberg ferromagnet. The critical exponent δ=4.761±0.129 is determined from the isothermal magnetization at TC. The scaling exponents corresponding to second order phase transition are consistent with the exponents from Kouvel-Fisher analysis and satisfy Widom's scaling relation δ=1+(γ/β). Additionally, they also satisfy the single scaling equation M(H,ɛ)=ɛβf±(H/ɛ) according to which the magnetization-field-temperature data around TC should collapse into two curves for temperatures below and above TC.

  17. Predicting Traffic Flow in Local Area Networks by the Largest Lyapunov Exponent

    Directory of Open Access Journals (Sweden)

    Yan Liu

    2016-01-01

    Full Text Available The dynamics of network traffic are complex and nonlinear, and chaotic behaviors and their prediction, which play an important role in local area networks (LANs, are studied in detail, using the largest Lyapunov exponent. With the introduction of phase space reconstruction based on the time sequence, the high-dimensional traffic is projected onto the low dimension reconstructed phase space, and a reduced dynamic system is obtained from the dynamic system viewpoint. Then, a numerical method for computing the largest Lyapunov exponent of the low-dimensional dynamic system is presented. Further, the longest predictable time, which is related to chaotic behaviors in the system, is studied using the largest Lyapunov exponent, and the Wolf method is used to predict the evolution of the traffic in a local area network by both Dot and Interval predictions, and a reliable result is obtained by the presented method. As the conclusion, the results show that the largest Lyapunov exponent can be used to describe the sensitivity of the trajectory in the reconstructed phase space to the initial values. Moreover, Dot Prediction can effectively predict the flow burst. The numerical simulation also shows that the presented method is feasible and efficient for predicting the complex dynamic behaviors in LAN traffic, especially for congestion and attack in networks, which are the main two complex phenomena behaving as chaos in networks.

  18. A MONTE-CARLO METHOD FOR ESTIMATING THE CORRELATION EXPONENT

    NARCIS (Netherlands)

    MIKOSCH, T; WANG, QA

    We propose a Monte Carlo method for estimating the correlation exponent of a stationary ergodic sequence. The estimator can be considered as a bootstrap version of the classical Hill estimator. A simulation study shows that the method yields reasonable estimates.

  19. Work-Family Enrichment: the Positive Side of Roles of Accumulation

    Directory of Open Access Journals (Sweden)

    Kadma Maia

    2015-08-01

    Full Text Available This article aims at understand up how the interaction can promote work-family enrichment in the roles developed by the Executive Secretaries of a public university. The approach used was the qualitative analysis research and data collection technique employed a semi-structured interview, applied to twenty executive secretaries, employed at the public universities. For the data interpretation, we used the technique of content analysis. The analytical results identified the existence of enrichment in this interaction. The learning opportunity to was mentioned as one of the most enriching element of the work, besides the family values as family enriching element. The family support and experience emerged as enrichment phenomena common to both domains. Regarding the implications of work-family interaction, the most perceived implications by respondents were: increased knowledge and skills, material and psychological benefits, improved quality of life and personal and professional fulfillment. The conclusion is that one should not emphasize the negative side of the work-family interaction if there are favorable resources to enrich this relationship. One should also value the positive side of the interaction to seek a balance between the demands of work and the ones of family is equally important, since the participation of Secretaries in family and work roles proved to be necessary and challenging and it can provide enrichment to the executive secretary roles in their work place.

  20. Fractal characters and hurst exponent of radon exhalation rate from uranium Tailings

    International Nuclear Information System (INIS)

    Hu Hanqiao; Tan Kaixuan; Li Chunguang; Lv Junwen; Liu Dong

    2010-01-01

    The uranium tailings radon exhalation is an important environmental problem. The change of the radon exhalation rate of uranium tailings with the time through laboratory experiments is measured, and the results show that the radon exhalation rate of the tailings change obviously with time in non-periodic oscillations. Applying fractal analysis to the radon exhalation rate time-series data by R/S method, the Hurst exponent of the entire time series data is 0.83, the fractal dimension is 1.17. Mobile Hurst exponent is between 0.5 and 0.8 in most cases. The Hurst exponent of the experiments in the later part are below 0.5. The exhalation rate of uranium tailings radon does not meet the long-term trend of random walk theory, the radon exhalation rate has long-term memory, but the short-term memory is not distinct. The radon exhalation from uranium tailings is a deterministic chaotic dynamics. (authors)

  1. Explanation of the values of Hack's drainage basin, river length scaling exponent

    Science.gov (United States)

    Hunt, A. G.

    2015-08-01

    Percolation theory can be used to find water flow paths of least resistance. The application of percolation theory to drainage networks allows identification of the range of exponent values that describe the tortuosity of rivers in real river networks, which is then used to generate the observed scaling between drainage basin area and channel length, a relationship known as Hack's law. Such a theoretical basis for Hack's law allows interpretation of the range of exponent values based on an assessment of the heterogeneity of the substrate.

  2. Density-scaling exponents and virial potential-energy correlation ...

    Indian Academy of Sciences (India)

    This paper investigates the relation between the density-scaling exponent γ and the virial potential energy correlation coefficient R at several thermodynamic state points in three dimensions for the generalized (2n, n) Lennard-Jones (LJ) system for n = 4, 9, 12, 18, as well as for the standard n = 6 LJ system in two,three, and ...

  3. Spectrum-based estimators of the bivariate Hurst exponent

    Czech Academy of Sciences Publication Activity Database

    Krištoufek, Ladislav

    2014-01-01

    Roč. 90, č. 6 (2014), art. 062802 ISSN 1539-3755 R&D Projects: GA ČR(CZ) GP14-11402P Institutional support: RVO:67985556 Keywords : bivariate Hurst exponent * power- law cross-correlations * estimation Subject RIV: AH - Economics Impact factor: 2.288, year: 2014 http://library.utia.cas.cz/separaty/2014/E/kristoufek-0436818.pdf

  4. The Nonverbal Communication of Positive Emotions: An Emotion Family Approach.

    Science.gov (United States)

    Sauter, Disa A

    2017-07-01

    This review provides an overview of the research on nonverbal expressions of positive emotions, organised into emotion families, that is, clusters sharing common characteristics. Epistemological positive emotions (amusement, relief, awe, and interest) are found to have distinct, recognisable displays via vocal or facial cues, while the agency-approach positive emotions (elation and pride) appear to be associated with recognisable visual, but not auditory, cues. Evidence is less strong for the prosocial emotions (love, compassion, gratitude, and admiration) in any modality other than touch, and there is little support for distinct recognisable signals of the savouring positive emotions (contentment, sensory pleasure, and desire). In closing, some limitations of extant work are noted and some proposals for future research are outlined.

  5. New prediction of chaotic time series based on local Lyapunov exponent

    International Nuclear Information System (INIS)

    Zhang Yong

    2013-01-01

    A new method of predicting chaotic time series is presented based on a local Lyapunov exponent, by quantitatively measuring the exponential rate of separation or attraction of two infinitely close trajectories in state space. After reconstructing state space from one-dimensional chaotic time series, neighboring multiple-state vectors of the predicting point are selected to deduce the prediction formula by using the definition of the local Lyapunov exponent. Numerical simulations are carried out to test its effectiveness and verify its higher precision over two older methods. The effects of the number of referential state vectors and added noise on forecasting accuracy are also studied numerically. (general)

  6. An Isomorphism between Lyapunov Exponents and Shannon's Channel Capacity

    Energy Technology Data Exchange (ETDEWEB)

    Friedland, Gerald [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Metere, Alfredo [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-06-07

    We demonstrate that discrete Lyapunov exponents are isomorphic to numeric overflows of the capacity of an arbitrary noiseless and memoryless channel in a Shannon communication model with feedback. The isomorphism allows the understanding of Lyapunov exponents in terms of Information Theory, rather than the traditional definitions in chaos theory. The result also implies alternative approaches to the calculation of related quantities, such as the Kolmogorov Sinai entropy which has been linked to thermodynamic entropy. This work provides a bridge between fundamental physics and information theory. It suggests, among other things, that machine learning and other information theory methods can be employed at the core of physics simulations.

  7. a Comparison of Three Hurst Exponent Approaches to Predict Nascent Bubbles in S&P500 Stocks

    Science.gov (United States)

    Fernández-Martínez, M.; Sánchez-Granero, M. A.; Muñoz Torrecillas, M. J.; McKelvey, Bill

    Since the pioneer contributions due to Vandewalle and Ausloos, the Hurst exponent has been applied by econophysicists as a useful indicator to deal with investment strategies when such a value is above or below 0.5, the Hurst exponent of a Brownian motion. In this paper, we hypothesize that the self-similarity exponent of financial time series provides a reliable indicator for herding behavior (HB) in the following sense: if there is HB, then the higher the price, the more the people will buy. This will generate persistence in the stocks which we shall measure by their self-similarity exponents. Along this work, we shall explore whether there is some connections between the self-similarity exponent of a stock (as a HB indicator) and the stock’s future performance under the assumption that the HB will last for some time. With this aim, three approaches to calculate the self-similarity exponent of a time series are compared in order to determine which performs best to identify the transition from random efficient market behavior to HB and hence, to detect the beginning of a bubble. Generalized Hurst Exponent, Detrended Fluctuation Analysis, and GM2 algorithms have been tested. Traditionally, researchers have focused on identifying the beginning of a crash. We study the beginning of the transition from efficient market behavior to a market bubble, instead. Our empirical results support that the higher (respectively the lower) the self-similarity index, the higher (respectively the lower) the mean of the price change, and hence, the better (respectively the worse) the performance of the corresponding stock. This would imply, as a consequence, that the transition process from random efficient market to HB has started. For experimentation purposes, S&P500 stock Index constituted our main data source.

  8. ACCURATE ESTIMATES OF CHARACTERISTIC EXPONENTS FOR SECOND ORDER DIFFERENTIAL EQUATION

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    In this paper, a second order linear differential equation is considered, and an accurate estimate method of characteristic exponent for it is presented. Finally, we give some examples to verify the feasibility of our result.

  9. Large N critical exponents for the chiral Heisenberg Gross-Neveu universality class

    OpenAIRE

    Gracey, J. A.

    2018-01-01

    We compute the large N critical exponents η, ηϕ and 1/ν in d dimensions in the chiral Heisenberg Gross-Neveu model to several orders in powers of 1/N. For instance, the large N conformal bootstrap method is used to determine η at O(1/N3) while the other exponents are computed to O(1/N2). Estimates of the exponents for a phase transition in graphene are given which are shown to be commensurate with other approaches. In particular the behavior of the exponents in 2

  10. An analysis of the financial crisis in the KOSPI market using Hurst exponents

    Science.gov (United States)

    Yim, Kyubin; Oh, Gabjin; Kim, Seunghwan

    2014-09-01

    Recently, the study of the financial crisis has progressed to include the concept of the complex system, thereby improving the understanding of this extreme event from a neoclassical economic perspective. To determine which variables are related to the financial event caused by the 2008 US subprime crisis using temporal correlations, we investigate the diverse variables that may explain the financial system. These variables include return, volatility, trading volume and inter-trade duration data sets within the TAQ data for 27 highly capitalized individual companies listed on the KOSPI stock market. During 2008 and 2009, the Hurst exponent for the return time series over the whole period was less than 0.5, and the Hurst exponents for other variables, such as the volatility, trading volume and inter-trade duration, were greater than 0.5. Additionally, we analyze the relationships between the variation of temporal correlation and market instability based on these Hurst exponents and the degree of multifractality. We find that for the data related to trading volume, the Hurst exponents do not allow us to detect changes in market status, such as changes from normal to abnormal status, whereas other variables, including the return, volatility and weekly inter-trade duration, indicate a significant change in market status after the Lehman Brothers' bankruptcy. In addition, the multifractality and the measurement defined by subtracting the Hurst exponent of the return time series from that of the volatility time series decrease sharply after the US subprime event and recover approximately 50 days after the Lehman Brothers' collapse. Our findings suggest that the temporal features of financial quantities in the TAQ data set and the market complexity perform very well at diagnosing financial market stability.

  11. An accurate algorithm to calculate the Hurst exponent of self-similar processes

    International Nuclear Information System (INIS)

    Fernández-Martínez, M.; Sánchez-Granero, M.A.; Trinidad Segovia, J.E.; Román-Sánchez, I.M.

    2014-01-01

    In this paper, we introduce a new approach which generalizes the GM2 algorithm (introduced in Sánchez-Granero et al. (2008) [52]) as well as fractal dimension algorithms (FD1, FD2 and FD3) (first appeared in Sánchez-Granero et al. (2012) [51]), providing an accurate algorithm to calculate the Hurst exponent of self-similar processes. We prove that this algorithm performs properly in the case of short time series when fractional Brownian motions and Lévy stable motions are considered. We conclude the paper with a dynamic study of the Hurst exponent evolution in the S and P500 index stocks. - Highlights: • We provide a new approach to properly calculate the Hurst exponent. • This generalizes FD algorithms and GM2, introduced previously by the authors. • This method (FD4) results especially appropriate for short time series. • FD4 may be used in both unifractal and multifractal contexts. • As an empirical application, we show that S and P500 stocks improved their efficiency

  12. An accurate algorithm to calculate the Hurst exponent of self-similar processes

    Energy Technology Data Exchange (ETDEWEB)

    Fernández-Martínez, M., E-mail: fmm124@ual.es [Department of Mathematics, Faculty of Science, Universidad de Almería, 04120 Almería (Spain); Sánchez-Granero, M.A., E-mail: misanche@ual.es [Department of Mathematics, Faculty of Science, Universidad de Almería, 04120 Almería (Spain); Trinidad Segovia, J.E., E-mail: jetrini@ual.es [Department of Accounting and Finance, Faculty of Economics and Business, Universidad de Almería, 04120 Almería (Spain); Román-Sánchez, I.M., E-mail: iroman@ual.es [Department of Accounting and Finance, Faculty of Economics and Business, Universidad de Almería, 04120 Almería (Spain)

    2014-06-27

    In this paper, we introduce a new approach which generalizes the GM2 algorithm (introduced in Sánchez-Granero et al. (2008) [52]) as well as fractal dimension algorithms (FD1, FD2 and FD3) (first appeared in Sánchez-Granero et al. (2012) [51]), providing an accurate algorithm to calculate the Hurst exponent of self-similar processes. We prove that this algorithm performs properly in the case of short time series when fractional Brownian motions and Lévy stable motions are considered. We conclude the paper with a dynamic study of the Hurst exponent evolution in the S and P500 index stocks. - Highlights: • We provide a new approach to properly calculate the Hurst exponent. • This generalizes FD algorithms and GM2, introduced previously by the authors. • This method (FD4) results especially appropriate for short time series. • FD4 may be used in both unifractal and multifractal contexts. • As an empirical application, we show that S and P500 stocks improved their efficiency.

  13. Using machine learning to replicate chaotic attractors and calculate Lyapunov exponents from data

    Science.gov (United States)

    Pathak, Jaideep; Lu, Zhixin; Hunt, Brian R.; Girvan, Michelle; Ott, Edward

    2017-12-01

    We use recent advances in the machine learning area known as "reservoir computing" to formulate a method for model-free estimation from data of the Lyapunov exponents of a chaotic process. The technique uses a limited time series of measurements as input to a high-dimensional dynamical system called a "reservoir." After the reservoir's response to the data is recorded, linear regression is used to learn a large set of parameters, called the "output weights." The learned output weights are then used to form a modified autonomous reservoir designed to be capable of producing an arbitrarily long time series whose ergodic properties approximate those of the input signal. When successful, we say that the autonomous reservoir reproduces the attractor's "climate." Since the reservoir equations and output weights are known, we can compute the derivatives needed to determine the Lyapunov exponents of the autonomous reservoir, which we then use as estimates of the Lyapunov exponents for the original input generating system. We illustrate the effectiveness of our technique with two examples, the Lorenz system and the Kuramoto-Sivashinsky (KS) equation. In the case of the KS equation, we note that the high dimensional nature of the system and the large number of Lyapunov exponents yield a challenging test of our method, which we find the method successfully passes.

  14. Hopf bifurcations, Lyapunov exponents and control of chaos for a class of centrifugal flywheel governor system

    International Nuclear Information System (INIS)

    Zhang Jiangang; Li Xianfeng; Chu Yandong; Yu Jianning; Chang Yingxiang

    2009-01-01

    In this paper, complex dynamical behavior of a class of centrifugal flywheel governor system is studied. These systems have a rich variety of nonlinear behavior, which are investigated here by numerically integrating the Lagrangian equations of motion. A tiny change in parameters can lead to an enormous difference in the long-term behavior of the system. Bubbles of periodic orbits may also occur within the bifurcation sequence. Hyperchaotic behavior is also observed in cases where two of the Lyapunov exponents are positive, one is zero, and one is negative. The routes to chaos are analyzed using Poincare maps, which are found to be more complicated than those of nonlinear rotational machines. Periodic and chaotic motions can be clearly distinguished by all of the analytical tools applied here, namely Poincare sections, bifurcation diagrams, Lyapunov exponents, and Lyapunov dimensions. This paper proposes a parametric open-plus-closed-loop approach to controlling chaos, which is capable of switching from chaotic motion to any desired periodic orbit. The theoretical work and numerical simulations of this paper can be extended to other systems. Finally, the results of this paper are of practical utility to designers of rotational machines.

  15. Zipf's law and influential factors of the Pareto exponent of the city size distribution: Evidence from China

    OpenAIRE

    GAO Hongying; WU Kangping

    2007-01-01

    This paper estimates the Pareto exponent of the city size (population size and economy size) distribution, all provinces, and three regions in China in 1997, 2000 and 2003 by OLS, comparatively analyzes the Pareto exponent cross section and times, and empirically analyzes the factors which impacts on the Pareto exponents of provinces. Our analyses show that the size distributions of cities in China follow the Pareto distribution and are of structural features. Variations in the value of the P...

  16. HIV-positive patients' and their families' comprehension of HIV- and ...

    African Journals Online (AJOL)

    HIV-positive patients' and their families' comprehension of HIV- and AIDS-related information. ... perceived that pre- and post-counselling provided an opportunity for information sharing, but that they need health care workers to spend more time with them, to be non-judgemental and to make more use of visual aids.

  17. Osteochondritis Dissecans Lesions in Family Members: Does a Positive Family History Impact Phenotypic Potency?

    Science.gov (United States)

    Gornitzky, Alex L; Mistovich, R Justin; Atuahuene, Brittany; Storey, Eileen P; Ganley, Theodore J

    2017-06-01

    Although repetitive microtrauma and athletic overuse patterns are most commonly associated with osteochondritis dissecans (OCD), recent studies have identified a potential genetic predisposition for OCD. Several case series have documented family pedigrees that support autosomal-dominant inheritance, but the families in these studies were all selected as a result of unique histories that may not accurately represent OCD inheritance patterns at large. Because there has been little investigation beyond these case reports, we aimed to describe a broader, more representative pattern of OCD inheritance applicable to all affected patients. (1) What proportion of patients treated for OCD of the knee have one or more immediate and/or extended family members with a history of OCD lesions? (2) Do patients with more phenotypically potent lesions, which we defined as patients with bilateral OCD lesions or patients who have undergone multiple procedures for OCD, have a higher frequency of affected relatives than those with less potent lesions? This retrospective study queried patient databases, diagnosis codes (International Classification of Diseases, 9th Revision), and surgical logs at a regional, tertiary care children's hospital to identify all patients treated over a 10-year period (March 2004-March 2014) by the senior author for OCD of the knee. All patients aged 0-18 years at the time of diagnosis were included. At our institution, patients with intact lesions are treated with a trial of conservative therapy; conversely, patients with a break in the articular cartilage and/or loose fragments of bone/cartilage are treated surgically. There were no OCD-specific contraindications to surgery. This search identified 543 patients. After patient identification, a questionnaire was designed that asked for the number, age, and gender of all immediate family members and the history of OCD lesions in any family member (immediate or extended). For all positive family members

  18. Reduction of a family of ideals

    OpenAIRE

    Rodak, Tomasz

    2015-01-01

    In the paper we prove that there exists a simultaneous reduction of one-parameter family of $\\mathfrak{m}_{n}$-primary ideals in the ring of germs of holomorphic functions. As a corollary we generalize the result of A. P\\l{}oski \\cite{ploski} on the semicontinuity of the \\L{}ojasiewicz exponent in a multiplicity-constant deformation.

  19. Statistical properties of the anomalous scaling exponent estimator based on time-averaged mean-square displacement

    Science.gov (United States)

    Sikora, Grzegorz; Teuerle, Marek; Wyłomańska, Agnieszka; Grebenkov, Denis

    2017-08-01

    The most common way of estimating the anomalous scaling exponent from single-particle trajectories consists of a linear fit of the dependence of the time-averaged mean-square displacement on the lag time at the log-log scale. We investigate the statistical properties of this estimator in the case of fractional Brownian motion (FBM). We determine the mean value, the variance, and the distribution of the estimator. Our theoretical results are confirmed by Monte Carlo simulations. In the limit of long trajectories, the estimator is shown to be asymptotically unbiased, consistent, and with vanishing variance. These properties ensure an accurate estimation of the scaling exponent even from a single (long enough) trajectory. As a consequence, we prove that the usual way to estimate the diffusion exponent of FBM is correct from the statistical point of view. Moreover, the knowledge of the estimator distribution is the first step toward new statistical tests of FBM and toward a more reliable interpretation of the experimental histograms of scaling exponents in microbiology.

  20. On fractality and chaos in Moroccan family business stock returns and volatility

    Science.gov (United States)

    Lahmiri, Salim

    2017-05-01

    The purpose of this study is to examine existence of fractality and chaos in returns and volatilities of family business companies listed on the Casablanca Stock Exchange (CSE) in Morocco, and also in returns and volatility of the CSE market index. Detrended fluctuation analysis based Hurst exponent and fractionally integrated generalized autoregressive conditional heteroskedasticity (FIGARCH) model are used to quantify fractality in returns and volatility time series respectively. Besides, the largest Lyapunov exponent is employed to quantify chaos in both time series. The empirical results from sixteen family business companies follow. For return series, fractality analysis show that most of family business returns listed on CSE exhibit anti-persistent dynamics, whilst market returns have persistent dynamics. Besides, chaos tests show that business family stock returns are not chaotic while market returns exhibit evidence of chaotic behaviour. For volatility series, fractality analysis shows that most of family business stocks and market index exhibit long memory in volatility. Furthermore, results from chaos tests show that volatility of family business returns is not chaotic, whilst volatility of market index is chaotic. These results may help understanding irregularities patterns in Moroccan family business stock returns and volatility, and how they are different from market dynamics.

  1. Parents’ Optimism, Positive Parenting, and Child Peer Competence in Mexican-Origin Families

    Science.gov (United States)

    Castro-Schilo, Laura; Ferrer, Emilio; Taylor, Zoe E.; Robins, Richard W.; Conger, Rand D.; Widaman, Keith F.

    2012-01-01

    SYNOPSIS Objective This study examined how parents’ optimism influences positive parenting and child peer competence in Mexican-origin families. Design A sample of 521 families (521 mothers, 438 fathers, and 521 11-year-olds) participated in the cross-sectional study. We used structural equation modeling to assess whether effective parenting would mediate the effect of parents’ optimism on child peer competence and whether mothers’ and fathers’ optimism would moderate the relation between positive parenting and child social competence. Results Mothers’ and fathers’ optimism were associated with effective parenting, which in turn was related to children’s peer competence. Mothers’ and fathers’ optimism also moderated the effect of parenting on child peer competence. High levels of parental optimism buffered children against poor parenting; at low levels of parental optimism, positive parenting was more strongly related to child peer competence. Conclusions Results are consistent with the hypothesis that positive parenting is promoted by parents’ optimism and is a proximal driver of child social competence. Parental optimism moderates effects of parenting on child outcomes. PMID:23526877

  2. Regularized semiclassical limits: Linear flows with infinite Lyapunov exponents

    KAUST Repository

    Athanassoulis, Agissilaos; Katsaounis, Theodoros; Kyza, Irene

    2016-01-01

    Semiclassical asymptotics for Schrödinger equations with non-smooth potentials give rise to ill-posed formal semiclassical limits. These problems have attracted a lot of attention in the last few years, as a proxy for the treatment of eigenvalue crossings, i.e. general systems. It has recently been shown that the semiclassical limit for conical singularities is in fact well-posed, as long as the Wigner measure (WM) stays away from singular saddle points. In this work we develop a family of refined semiclassical estimates, and use them to derive regularized transport equations for saddle points with infinite Lyapunov exponents, extending the aforementioned recent results. In the process we answer a related question posed by P.L. Lions and T. Paul in 1993. If we consider more singular potentials, our rigorous estimates break down. To investigate whether conical saddle points, such as -|x|, admit a regularized transport asymptotic approximation, we employ a numerical solver based on posteriori error control. Thus rigorous upper bounds for the asymptotic error in concrete problems are generated. In particular, specific phenomena which render invalid any regularized transport for -|x| are identified and quantified. In that sense our rigorous results are sharp. Finally, we use our findings to formulate a precise conjecture for the condition under which conical saddle points admit a regularized transport solution for the WM. © 2016 International Press.

  3. Regularized semiclassical limits: Linear flows with infinite Lyapunov exponents

    KAUST Repository

    Athanassoulis, Agissilaos

    2016-08-30

    Semiclassical asymptotics for Schrödinger equations with non-smooth potentials give rise to ill-posed formal semiclassical limits. These problems have attracted a lot of attention in the last few years, as a proxy for the treatment of eigenvalue crossings, i.e. general systems. It has recently been shown that the semiclassical limit for conical singularities is in fact well-posed, as long as the Wigner measure (WM) stays away from singular saddle points. In this work we develop a family of refined semiclassical estimates, and use them to derive regularized transport equations for saddle points with infinite Lyapunov exponents, extending the aforementioned recent results. In the process we answer a related question posed by P.L. Lions and T. Paul in 1993. If we consider more singular potentials, our rigorous estimates break down. To investigate whether conical saddle points, such as -|x|, admit a regularized transport asymptotic approximation, we employ a numerical solver based on posteriori error control. Thus rigorous upper bounds for the asymptotic error in concrete problems are generated. In particular, specific phenomena which render invalid any regularized transport for -|x| are identified and quantified. In that sense our rigorous results are sharp. Finally, we use our findings to formulate a precise conjecture for the condition under which conical saddle points admit a regularized transport solution for the WM. © 2016 International Press.

  4. Hurst's Exponent Determination for Radial Distribution Functions of In, Sn and In-40 wt%Sn Melt

    International Nuclear Information System (INIS)

    Zhou Yong-Zhi; Li Mei; Geng Hao-Ran; Yang Zhong-Xi; Sun Chun-Jing

    2011-01-01

    Hurst's exponent of radial distribution functions (RDFs) within the short-range scope of In, Sn and In-40 wt % Sn melts are determined by the rescaled range analysis method. Hurst's exponents H are between 0.94 and 0.97, which display long-range dependence. Within short-range scope, the number of particles from a reference particle belongs to fractional Brownian motion. After RDF serials are randomly scrambled, Hurst's exponents all dramatically dropped, which proves long-range dependence. H irregularly varies as the temperature rises, but the change tendency is not consistent with the correlation radius r c . (general)

  5. Non-universality of critical exponents in the paraconductivity of short-coherence-length superconductors

    International Nuclear Information System (INIS)

    Gauzzi, A.

    1993-01-01

    The Aslamazov-Larkin paraconductivity term is calculated in the case of sufficiently small superconducting coherence length. It is found that the critical exponent of paraconductivity depends on the short-wavelength cut-off of the fluctuation spectrum in the whole Ginzburg-Landau mean-field region. Hence, it is predicted that the Aslamazov-Larkin universal relation between the critical exponent of paraconductivity and the dimensionality of the superconducting state is no longer valid in short-coherence-length superconductors. This prediction is confirmed by paraconductivity measurements on cuprate superconductors. (orig.)

  6. Family presence during resuscitation: A Canadian Critical Care Society position paper.

    Science.gov (United States)

    Oczkowski, Simon John Walsh; Mazzetti, Ian; Cupido, Cynthia; Fox-Robichaud, Alison E

    2015-01-01

    Recent evidence suggests that patient outcomes are not affected by the offering of family presence during resuscitation (FPDR), and that psychological outcomes are neutral or improved in family members of adult patients. The exclusion of family members from the resuscitation area should, therefore, be reassessed. The present Canadian Critical Care Society position paper is designed to help clinicians and institutions decide whether to incorporate FPDR as part of their routine clinical practice, and to offer strategies to implement FPDR successfully. The authors conducted a literature search of the perspectives of health care providers, patients and families on the topic of FPDR, and considered the relevant ethical values of beneficence, nonmaleficence, autonomy and justice in light of the clinical evidence for FPDR. They reviewed randomized controlled trials and observational studies of FPDR to determine strategies that have been used to screen family members, select appropriate chaperones and educate staff. FPDR is an ethically sound practice in Canada, and may be considered for the families of adult and pediatric patients in the hospital setting. Hospitals that choose to implement FPDR should develop transparent policies regarding which family members are to be offered the opportunity to be present during the resuscitation. Experienced chaperones should accompany and support family members in the resuscitation area. Intensive educational interventions and increasing experience with FPDR are associated with increased support for the practice from health care providers. FPDR should be considered to be an important component of patient and family-centred care.

  7. On Hurst exponent estimation under heavy-tailed distributions

    Czech Academy of Sciences Publication Activity Database

    Baruník, Jozef; Krištoufek, Ladislav

    2010-01-01

    Roč. 389, č. 18 (2010), s. 3844-3855 ISSN 0378-4371 R&D Projects: GA ČR GA402/09/0965 Grant - others:GA UK(CZ) 118310; GA UK(CZ) 46108 Institutional research plan: CEZ:AV0Z10750506 Keywords : high frequency data analysis * heavy tails * Hurst exponent Subject RIV: AH - Economics Impact factor: 1.521, year: 2010 http://library.utia.cas.cz/separaty/2010/E/barunik-0343525.pdf

  8. A modified approach to predict pore pressure using the D exponent method: An example from the Carbonera Formation, Colombia

    International Nuclear Information System (INIS)

    Solano, Yully P; Uribe, Rodolfo; Frydman, Marcelo; Saavedra, Nestor F; Calderon, Zuly H

    2007-01-01

    The methodology for the pore pressure prediction known as an exponent is o function of an exponent of adjustment that was originally defined for the Gulf of Mexico (Jorden and Shirley, 1966; Eaton, 1972). A limiting factor of this methodology is the definition of the normal compaction trend (NCT), which needs to be interpreted from the data (Mouchet and Mitchell, 1989). In this study, the D exponent methodology was modified to make it applicable to the Oligocene Carbonera Formation in an oil field of the llanos foothills Colombia. The approach consisted of calculating the ratio between affective stress and the D exponent of each wall, in order to find a robust NCT for the entire field, thus reducing subjectivity in the traditional d exponent methodology. Pore pressure determinations from Measured Direct Tests (MDT) at one wall confirm the predictive capability of our approach

  9. Are familial factors underlying the association between socioeconomic position and prescription medicine?

    DEFF Research Database (Denmark)

    Madsen, Mia; Andersen, Per Kragh; Gerster, Mette

    2013-01-01

    OBJECTIVES: Although well established, the association between socioeconomic position and health and health behaviour is not clearly understood, and it has been speculated that familial factors, for example, dispositional factors or exposures in the rearing environment, may be underlying the asso......OBJECTIVES: Although well established, the association between socioeconomic position and health and health behaviour is not clearly understood, and it has been speculated that familial factors, for example, dispositional factors or exposures in the rearing environment, may be underlying...... and the Danish Registry of Medicinal Product statistics. A total of 8582 monozygotic (MZ) and 15 788 dizygotic same sex (DZSS) twins were included. OUTCOME MEASURES: Number of prescription fillings during follow-up (1995-2005) was analysed according to education and income. Results of unpaired and intrapair...

  10. Fast and unbiased estimator of the time-dependent Hurst exponent

    Science.gov (United States)

    Pianese, Augusto; Bianchi, Sergio; Palazzo, Anna Maria

    2018-03-01

    We combine two existing estimators of the local Hurst exponent to improve both the goodness of fit and the computational speed of the algorithm. An application with simulated time series is implemented, and a Monte Carlo simulation is performed to provide evidence of the improvement.

  11. Directional maximum likelihood self-estimation of the path-loss exponent

    NARCIS (Netherlands)

    Hu, Y.; Leus, G.J.T.; Dong, Min; Zheng, Thomas Fang

    2016-01-01

    The path-loss exponent (PLE) is a key parameter in wireless propagation channels. Therefore, obtaining the knowledge of the PLE is rather significant for assisting wireless communications and networking to achieve a better performance. Most existing methods for estimating the PLE not only require

  12. Improved integrability of the gradients of solutions of elliptic equations with variable nonlinearity exponent

    International Nuclear Information System (INIS)

    Zhikov, Vasilii V; Pastukhova, Svetlana E

    2008-01-01

    Elliptic equations of p(x)-Laplacian type are investigated. There is a well-known logarithmic condition on the modulus of continuity of the nonlinearity exponent p(x), which ensures that a Laplacian with variable order of nonlinearity inherits many properties of the usual p-Laplacian of constant order. One of these is the so-called improved integrability of the gradient of the solution. It is proved in this paper that this property holds also under a slightly more general condition on the exponent p(x), although then the improvement of integrability is logarithmic rather than power-like. The method put forward is based on a new generalization of Gehring's lemma, which relies upon the reverse Hoelder inequality 'with increased support and exponent on the right-hand side'. A counterexample is constructed that reveals the extent to which the condition on the modulus of continuity obtained is sharp. Bibliography: 28 titles.

  13. The Exponent of High-frequency Source Spectral Falloff and Contribution to Source Parameter Estimates

    Science.gov (United States)

    Kiuchi, R.; Mori, J. J.

    2015-12-01

    As a way to understand the characteristics of the earthquake source, studies of source parameters (such as radiated energy and stress drop) and their scaling are important. In order to estimate source parameters reliably, often we must use appropriate source spectrum models and the omega-square model is most frequently used. In this model, the spectrum is flat in lower frequencies and the falloff is proportional to the angular frequency squared. However, Some studies (e.g. Allmann and Shearer, 2009; Yagi et al., 2012) reported that the exponent of the high frequency falloff is other than -2. Therefore, in this study we estimate the source parameters using a spectral model for which the falloff exponent is not fixed. We analyze the mainshock and larger aftershocks of the 2008 Iwate-Miyagi Nairiku earthquake. Firstly, we calculate the P wave and SH wave spectra using empirical Green functions (EGF) to remove the path effect (such as attenuation) and site effect. For the EGF event, we select a smaller earthquake that is highly-correlated with the target event. In order to obtain the stable results, we calculate the spectral ratios using a multitaper spectrum analysis (Prieto et al., 2009). Then we take a geometric mean from multiple stations. Finally, using the obtained spectra ratios, we perform a grid search to determine the high frequency falloffs, as well as corner frequency of both of events. Our results indicate the high frequency falloff exponent is often less than 2.0. We do not observe any regional, focal mechanism, or depth dependencies for the falloff exponent. In addition, our estimated corner frequencies and falloff exponents are consistent between the P wave and SH wave analysis. In our presentation, we show differences in estimated source parameters using a fixed omega-square model and a model allowing variable high-frequency falloff.

  14. Numerical difficulties to obtain 3-d critical exponents from platonic solids

    International Nuclear Information System (INIS)

    Alcaraz, F.C.; Herrmann, H.J.

    1985-01-01

    The possibility to extract critical exponents of 3-d systems exploring the mass gap amplitudes of platonic solids is tested. For the Ising model the proposed method does not work for numerical reasons. (Author) [pt

  15. Overcoming Barriers to Family Planning through Integration: Perspectives of HIV-Positive Men in Nyanza Province, Kenya

    Directory of Open Access Journals (Sweden)

    Rachel L. Steinfeld

    2013-01-01

    Full Text Available This study explored barriers to and facilitators of using family planning services among HIV-positive men in Nyanza Province, Kenya. From May to June 2010, in-depth interviews were conducted with 30 men receiving care at 15 HIV clinics. The key barriers to the use of family planning included concerns about side effects of contraceptives, lack of knowledge about contraceptive methods, myths and misconceptions including fear of infertility, structural barriers such as staffing shortages at HIV clinics, and a lack of male focus in family planning methods and service delivery. The integration of family planning into HIV clinics including family planning counseling and education was cited as an important strategy to improve family planning receptivity among men. Integrating family planning into HIV services is a promising strategy to facilitate male involvement in family planning. Integration needs to be rigorously evaluated in order to measure its impact on unmet need for contraception among HIV-positive women and their partners and assure that it is implemented in a manner that engages both men and women.

  16. Investigating textural controls on Archie's porosity exponent using process-based, pore-scale modelling

    Science.gov (United States)

    Niu, Q.; Zhang, C.

    2017-12-01

    Archie's law is an important empirical relationship linking the electrical resistivity of geological materials to their porosity. It has been found experimentally that the porosity exponent m in Archie's law in sedimentary rocks might be related to the degree of cementation, and therefore m is termed as "cementation factor" in most literatures. Despite it has been known for many years, there is lack of well-accepted physical interpretations of the porosity exponent. Some theoretical and experimental evidences have also shown that m may be controlled by the particle and/or pore shape. In this study, we conduct a pore-scale modeling of the porosity exponent that incorporates different geological processes. The evolution of m of eight synthetic samples with different particle sizes and shapes are calculated during two geological processes, i.e., compaction and cementation. The numerical results show that in dilute conditions, m is controlled by the particle shape. As the samples deviate from dilute conditions, m increases gradually due to the strong interaction between particles. When the samples are at static equilibrium, m is noticeably larger than its values at dilution condition. The numerical simulation results also show that both geological compaction and cementation induce a significant increase in m. In addition, the geometric characteristics of these samples (e.g., pore space/throat size, and their distributions) during compaction and cementation are also calculated. Preliminary analysis shows a unique correlation between the pore size broadness and porosity exponent for all eight samples. However, such a correlation is not found between m and other geometric characteristics.

  17. Quality of Gaussian basis sets: direct optimization of orbital exponents by the method of conjugate gradients

    International Nuclear Information System (INIS)

    Kari, R.E.; Mezey, P.G.; Csizmadia, I.G.

    1975-01-01

    Expressions are given for calculating the energy gradient vector in the exponent space of Gaussian basis sets and a technique to optimize orbital exponents using the method of conjugate gradients is described. The method is tested on the (9/sups/5/supp/) Gaussian basis space and optimum exponents are determined for the carbon atom. The analysis of the results shows that the calculated one-electron properties converge more slowly to their optimum values than the total energy converges to its optimum value. In addition, basis sets approximating the optimum total energy very well can still be markedly improved for the prediction of one-electron properties. For smaller basis sets, this improvement does not warrant the necessary expense

  18. Critical exponents in the transition to chaos in one-dimensional

    Indian Academy of Sciences (India)

    We report the numerically evaluated critical exponents associated with the scaling of generalized fractal dimensions during the transition from order to chaos. The analysis is carried out in detail in the context of unimodal and bimodal maps representing typical one-dimensional discrete dynamical systems. The behavior of ...

  19. Dynamical generalized Hurst exponent as a tool to monitor unstable periods in financial time series

    Science.gov (United States)

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

    2012-06-01

    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.

  20. Positive Youth Development, Life Satisfaction and Problem Behaviors of Adolescents in Intact and Non-Intact Families in Hong Kong

    Directory of Open Access Journals (Sweden)

    Daniel Tan Lei Shek

    2013-08-01

    Full Text Available This study investigated whether Chinese adolescents living in intact and non-intact families differed in their positive development, life satisfaction, and risk behavior. A total of 3,328 Secondary 1 students responded to measures of positive youth development (such as resilience and psychosocial competencies, life satisfaction, and risk behavior (substance abuse, delinquency, Internet addiction, consumption of pornographic materials, self-harm, and behavioral intention to engage in problem behavior. Findings revealed that adolescents growing up in intact families reported higher levels of positive developmental outcomes and life satisfaction as compared with adolescents from non-intact families. Adolescents in non-intact families also reported higher levels of risk behaviors than those growing up in intact families.

  1. Metamotifs - a generative model for building families of nucleotide position weight matrices

    Directory of Open Access Journals (Sweden)

    Down Thomas A

    2010-06-01

    Full Text Available Abstract Background Development of high-throughput methods for measuring DNA interactions of transcription factors together with computational advances in short motif inference algorithms is expanding our understanding of transcription factor binding site motifs. The consequential growth of sequence motif data sets makes it important to systematically group and categorise regulatory motifs. It has been shown that there are familial tendencies in DNA sequence motifs that are predictive of the family of factors that binds them. Further development of methods that detect and describe familial motif trends has the potential to help in measuring the similarity of novel computational motif predictions to previously known data and sensitively detecting regulatory motifs similar to previously known ones from novel sequence. Results We propose a probabilistic model for position weight matrix (PWM sequence motif families. The model, which we call the 'metamotif' describes recurring familial patterns in a set of motifs. The metamotif framework models variation within a family of sequence motifs. It allows for simultaneous estimation of a series of independent metamotifs from input position weight matrix (PWM motif data and does not assume that all input motif columns contribute to a familial pattern. We describe an algorithm for inferring metamotifs from weight matrix data. We then demonstrate the use of the model in two practical tasks: in the Bayesian NestedMICA model inference algorithm as a PWM prior to enhance motif inference sensitivity, and in a motif classification task where motifs are labelled according to their interacting DNA binding domain. Conclusions We show that metamotifs can be used as PWM priors in the NestedMICA motif inference algorithm to dramatically increase the sensitivity to infer motifs. Metamotifs were also successfully applied to a motif classification problem where sequence motif features were used to predict the family of

  2. On nonlinear evolution variational inequalities involving variable exponent

    Directory of Open Access Journals (Sweden)

    Mingqi Xiang

    2013-12-01

    Full Text Available In this paper, we discuss a class of quasilinear evolution variational inequalities with variable exponent growth conditions in a generalized Sobolev space. We obtain the existence of weak solutions by means of penalty method. Moreover, we study the extinction properties of weak solutions to parabolic inequalities and provide a sufficient condition that makes the weak solutions vanish in a finite time. The existence of global attractors for weak solutions is also obtained via the theories of multi-valued semiflow.

  3. Magnetic entropy change and critical exponents in double perovskite Y{sub 2}NiMnO{sub 6}

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, G. [School of Physical Sciences, Jawaharlal Nehru University, New Delhi-110067 (India); Tripathi, T.S. [Inter-University Accelerator Centre, New Delhi-110067 (India); Saha, J. [School of Physical Sciences, Jawaharlal Nehru University, New Delhi-110067 (India); Patnaik, S., E-mail: spatnaik@mail.jnu.ac.in [School of Physical Sciences, Jawaharlal Nehru University, New Delhi-110067 (India)

    2014-11-15

    We report the magnetic entropy change (ΔS{sub M}) and the critical exponents in the double perovskite manganite Y{sub 2}NiMnO{sub 6} with a ferromagnetic to paramagnetic transition T{sub C}∼85K. For a magnetic field change ΔH=80kOe, a maximum magnetic entropy change ΔS{sub M}=−6.57J/kgK is recorded around T{sub C}. The critical exponents β=0.363±0.05 and γ=1.331±0.09 obtained from power law fitting to spontaneous magnetization M{sub S}(T) and the inverse initial susceptibility χ{sub 0}{sup −1}(T) satisfy well to values derived for a 3D-Heisenberg ferromagnet. The critical exponent δ=4.761±0.129 is determined from the isothermal magnetization at T{sub C}. The scaling exponents corresponding to second order phase transition are consistent with the exponents from Kouvel–Fisher analysis and satisfy Widom's scaling relation δ=1+(γ/β). Additionally, they also satisfy the single scaling equation M(H,ϵ)=ϵ{sup β}f±(H/ϵ{sup β+γ}) according to which the magnetization-field-temperature data around T{sub C} should collapse into two curves for temperatures below and above T{sub C}. - Highlights: • The magneto-caloric (MC) effect and the critical exponent analysis in Y{sub 2}NiMnO{sub 6} are studied. • Methods such as Kouvel–Fisher, Widom's and Mean-Field scaling are used. • The magnetic ground state in Y{sub 2}NiMnO{sub 6} is based on isotropic 3D Heisenberg model. • The large MC effect can be utilized towards magnetic refrigeration around 77 K. • The nearest neighbor interaction in Y{sub 2}NiMnO{sub 6} rules out ferroelectricity.

  4. Gaussian fluctuation of the diffusion exponent of virus capsid in a living cell nucleus

    Science.gov (United States)

    Itto, Yuichi

    2018-05-01

    In their work [4], Bosse et al. experimentally showed that virus capsid exhibits not only normal diffusion but also anomalous diffusion in nucleus of a living cell. There, it was found that the distribution of fluctuations of the diffusion exponent characterizing them takes the Gaussian form, which is, quite remarkably, the same form for two different types of the virus. This suggests high robustness of such fluctuations. Here, the statistical property of local fluctuations of the diffusion exponent of the virus capsid in the nucleus is studied. A maximum-entropy-principle approach (originally proposed for a different virus in a different cell) is applied for obtaining the fluctuation distribution of the exponent. Largeness of the number of blocks identified with local areas of interchromatin corrals is also examined based on the experimental data. It is shown that the Gaussian distribution of the local fluctuations can be derived, in accordance with the above form. In addition, it is quantified how the fluctuation distribution on a long time scale is different from the Gaussian distribution.

  5. Effect of parental family history of Alzheimer's disease on serial position profiles.

    Science.gov (United States)

    La Rue, Asenath; Hermann, Bruce; Jones, Jana E; Johnson, Sterling; Asthana, Sanjay; Sager, Mark A

    2008-07-01

    An exaggerated recency effect (ie, disproportionate recall of last-presented items) has been consistently observed in the word list learning of patients with Alzheimer's disease (AD). Our study sought to determine whether there were similar alterations in serial position learning among asymptomatic persons at risk for AD as a result of parental family history. Subjects included 623 asymptomatic middle-aged children of patients with AD (median, 53 years) and 157 control participants whose parents survived to at least age 70 without AD or other memory disorders. All participants were administered the Rey Auditory Verbal Learning Test, which requires learning and recall of 15 unrelated nouns. There was no significant difference in total words recalled between the AD children and control groups. However, compared with controls, AD children exhibited a significantly greater tendency to recall words from the end (recency) versus beginning (primacy) of the list. Serial position effects were unrelated to apolipoprotein allele epsilon 4 or depressive symptoms. Asymptomatic persons at risk for AD by virtue of family history do not show a difference in total words recalled compared with controls, but they exhibit a distinctly different serial position curve, suggesting greater reliance on immediate as opposed to episodic memory. This is the same serial position pattern observed in mild AD, seen here in reduced severity. Longitudinal follow-up is planned to determine whether changes in serial position patterns are a meaningful marker for preclinical detection of AD.

  6. The Role of Positive Psychological Capital and the Family Function in Prediction of Happiness in high school students

    Directory of Open Access Journals (Sweden)

    F rashidi kochi

    2016-11-01

    Full Text Available The aim of this study was to determine the role of positive psychological capital and family functioning in predicting happiness among adolescence. Correlational research method was recruited to analyze the data. The sample comprised of 290 high Scholl students that selected by the convenience sampling method. In this research Snyder’s hope, Nezami and Colleagues self-efficacy, Scheier and Carver's optimism, McMaster's family functioning and Connor and Davidson's Resiliency and Oxford happiness questionnaire used to collect data. Pearson correlation and stepwise regression were used to analyze data. The finding showed that there was a significant positive relationship between family function components and positive psychological capital with happiness. The results of stepwise regression showed that roles, Resiliency, self-efficacy, optimism and emotion expression had significant and important role in predicting happiness. Totally, explained 35% of the variance happiness. In conclusion, these findings indicate the importance roles of family and positive psychological capital in adolescence's happiness.

  7. Nonlinear anisotropic elliptic equations with variable exponents and degenerate coercivity

    Directory of Open Access Journals (Sweden)

    Hocine Ayadi

    2018-02-01

    Full Text Available In this article, we prove the existence and the regularity of distributional solutions for a class of nonlinear anisotropic elliptic equations with $p_i(x$ growth conditions, degenerate coercivity and $L^{m(\\cdot}$ data, with $m(\\cdot$ being small, in appropriate Lebesgue-Sobolev spaces with variable exponents. The obtained results extend some existing ones [8,10].

  8. Computation of the Lyapunov exponents in the compass-gait model under OGY control via a hybrid Poincaré map

    International Nuclear Information System (INIS)

    Gritli, Hassène; Belghith, Safya

    2015-01-01

    Highlights: • A numerical calculation method of the Lyapunov exponents in the compass-gait model under OGY control is proposed. • A new linearization method of the impulsive hybrid dynamics around a one-periodic hybrid limit cycle is achieved. • We develop a simple analytical expression of a controlled hybrid Poincaré map. • A dimension reduction of the hybrid Poincaré map is realized. • We describe the numerical computation procedure of the Lyapunov exponents via the designed hybrid Poincaré map. - Abstract: This paper aims at providing a numerical calculation method of the spectrum of Lyapunov exponents in a four-dimensional impulsive hybrid nonlinear dynamics of a passive compass-gait model under the OGY control approach by means of a controlled hybrid Poincaré map. We present a four-dimensional simplified analytical expression of such hybrid map obtained by linearizing the uncontrolled impulsive hybrid nonlinear dynamics around a desired one-periodic passive hybrid limit cycle. In order to compute the spectrum of Lyapunov exponents, a dimension reduction of the controlled hybrid Poincaré map is realized. The numerical calculation of the spectrum of Lyapunov exponents using the reduced-dimension controlled hybrid Poincaré map is given in detail. In order to show the effectiveness of the developed method, the spectrum of Lyapunov exponents is calculated as the slope (bifurcation) parameter varies and hence used to predict the walking dynamics behavior of the compass-gait model under the OGY control.

  9. Brief communication: Possible explanation of the values of Hack's drainage basin, river length scaling exponent

    Science.gov (United States)

    Hunt, Allen G.

    2016-04-01

    Percolation theory can be used to find water flow paths of least resistance. Application of percolation theory to drainage networks allows identification of the range of exponent values that describe the tortuosity of rivers in real river networks, which is then used to generate the observed scaling between drainage basin area and channel length, a relationship known as Hack's law. Such a theoretical basis for Hack's law may allow interpretation of the range of exponent values based on an assessment of the heterogeneity of the substrate.

  10. Examining the "Neglected Side of the Work-Family Interface": Antecedents of Positive and Negative Family-to-Work Spillover

    Science.gov (United States)

    Stevens, Daphne Pedersen; Minnotte, Krista Lynn; Mannon, Susan E.; Kiger, Gary

    2007-01-01

    This study extends previous research by Dilworth by examining antecedents of both positive and negative family-to-work spillover--a long-neglected area of research. It also uses an extended definition of domestic labor that includes emotion work and status enhancement. Using data from a random sample of dual-earner couples, the study found gender…

  11. Work-family culture, work-family interference and well-being at work : iIs it possible to distinguish between a positive and a negative process?

    NARCIS (Netherlands)

    Peeters, M.C.W.; Wattez, C.; Demerouti, E.; Regt, de W.

    2009-01-01

    Purpose – The purpose of this paper is to examine whether work-family (WF) interference functions as an explaining mechanism in the link between work-family culture and well-being, hereby distinguishing between a negative and a positive process. The negative, energy depleting process initiates from

  12. Relation between the Hurst Exponent and the Efficiency of Self-organization of a Deformable System

    Science.gov (United States)

    Alfyorova, E. A.; Lychagin, D. V.

    2018-04-01

    We have established the degree of self-organization of a system under plastic deformation at different scale levels. Using fractal analysis, we have determined the Hurst exponent and correlation lengths in the region of formation of a corrugated (wrinkled) structure in [111] nickel single crystals under compression. This has made it possible to single out two (micro-and meso-) levels of self-organization in the deformable system. A qualitative relation between the values of the Hurst exponent and the stages of the stress-strain curve has been established.

  13. Critical exponents for diluted resistor networks.

    Science.gov (United States)

    Stenull, O; Janssen, H K; Oerding, K

    1999-05-01

    An approach by Stephen [Phys. Rev. B 17, 4444 (1978)] is used to investigate the critical properties of randomly diluted resistor networks near the percolation threshold by means of renormalized field theory. We reformulate an existing field theory by Harris and Lubensky [Phys. Rev. B 35, 6964 (1987)]. By a decomposition of the principal Feynman diagrams, we obtain diagrams which again can be interpreted as resistor networks. This interpretation provides for an alternative way of evaluating the Feynman diagrams for random resistor networks. We calculate the resistance crossover exponent phi up to second order in epsilon=6-d, where d is the spatial dimension. Our result phi=1+epsilon/42+4epsilon(2)/3087 verifies a previous calculation by Lubensky and Wang, which itself was based on the Potts-model formulation of the random resistor network.

  14. Statistics of semiflexible self-avoiding trails on a family of two-dimensional compact fractals

    International Nuclear Information System (INIS)

    Živić, I; Elezović-Hadžić, S; Milošević, S

    2011-01-01

    We have applied the exact and Monte Carlo renormalization group (MCRG) method to study the statistics of semiflexible self-avoiding trails (SATs) on the family of plane-filling (PF) fractals. Each fractal of the family is compact, that is, the fractal dimension d f is equal to 2 for all members of the PF family, which are enumerated by an odd integer b, 3≤b<∞. Varying values of the stiffness parameter s of trails from 1 to 0 (so that when s decreases the trail stiffness increases) we calculate exactly (for 3 ≤ b ≤ 7) and through the MCRG approach (for b ≤ 201) the sets of the critical exponents ν (associated with the mean squared end-to-end distances of SATs) and γ (associated with the total number of different SATs). Our results show that critical exponents are stiffness dependent functions, so that ν(s) is a monotonically decreasing function of s, for each studied b, whereas γ(s) displays a non-monotonic behavior for some values of b. On the other hand, by fixing the stiffness parameter s, our results show clearly that for highly flexible trails (with s = 1 and 0.9) ν is a non-monotonic function of b, while for stiffer SATs (with s ≤ 0.7) ν monotonically decreases with b. We also show that γ(b) increases with increasing b, independently of s. Finally, we compare the obtained SAT data with those obtained for the semiflexible self-avoiding walk (SAW) model on the same fractal family, and for both models we discuss behavior of the studied exponents in the fractal-to-Euclidean crossover region b→∞

  15. Riemannian theory of Hamiltonian chaos and Lyapunov exponents

    Science.gov (United States)

    Casetti, Lapo; Clementi, Cecilia; Pettini, Marco

    1996-12-01

    A nonvanishing Lyapunov exponent λ1 provides the very definition of deterministic chaos in the solutions of a dynamical system; however, no theoretical mean of predicting its value exists. This paper copes with the problem of analytically computing the largest Lyapunov exponent λ1 for many degrees of freedom Hamiltonian systems as a function of ɛ=E/N, the energy per degree of freedom. The functional dependence λ1(ɛ) is of great interest because, among other reasons, it detects the existence of weakly and strongly chaotic regimes. This aim, the analytic computation of λ1(ɛ), is successfully reached within a theoretical framework that makes use of a geometrization of Newtonian dynamics in the language of Riemannian differential geometry. An alternative point of view about the origin of chaos in these systems is obtained independently of the standard explanation based on homoclinic intersections. Dynamical instability (chaos) is here related to curvature fluctuations of the manifolds whose geodesics are natural motions and is described by means of the Jacobi-Levi-Civita equation (JLCE) for geodesic spread. In this paper it is shown how to derive from the JLCE an effective stability equation. Under general conditions, this effective equation formally describes a stochastic oscillator; an analytic formula for the instability growth rate of its solutions is worked out and applied to the Fermi-Pasta-Ulam β model and to a chain of coupled rotators. Excellent agreement is found between the theoretical prediction and numeric values of λ1(ɛ) for both models.

  16. Exponential convergence for nonlinear diffusion problems with positive lateral boundary conditions

    International Nuclear Information System (INIS)

    Holland, C.J.; Berryman, J.G.

    1985-01-01

    It is established that the solution u of u/sub t/ = Δ(u/sup m/)>0, with positive initial data, positive lateral boundary data, and positive exponent m, converges exponentially to the solution v of the corresponding stationary equation Δ(v/sup m/) = 0. The analysis also provides the form of the leading contribution to the difference

  17. Lyapunov Exponent and Out-of-Time-Ordered Correlator's Growth Rate in a Chaotic System.

    Science.gov (United States)

    Rozenbaum, Efim B; Ganeshan, Sriram; Galitski, Victor

    2017-02-24

    It was proposed recently that the out-of-time-ordered four-point correlator (OTOC) may serve as a useful characteristic of quantum-chaotic behavior, because, in the semiclassical limit ℏ→0, its rate of exponential growth resembles the classical Lyapunov exponent. Here, we calculate the four-point correlator C(t) for the classical and quantum kicked rotor-a textbook driven chaotic system-and compare its growth rate at initial times with the standard definition of the classical Lyapunov exponent. Using both quantum and classical arguments, we show that the OTOC's growth rate and the Lyapunov exponent are, in general, distinct quantities, corresponding to the logarithm of the phase-space averaged divergence rate of classical trajectories and to the phase-space average of the logarithm, respectively. The difference appears to be more pronounced in the regime of low kicking strength K, where no classical chaos exists globally. In this case, the Lyapunov exponent quickly decreases as K→0, while the OTOC's growth rate may decrease much slower, showing a higher sensitivity to small chaotic islands in the phase space. We also show that the quantum correlator as a function of time exhibits a clear singularity at the Ehrenfest time t_{E}: transitioning from a time-independent value of t^{-1}lnC(t) at ttime at t>t_{E}. We note that the underlying physics here is the same as in the theory of weak (dynamical) localization [Aleiner and Larkin, Phys. Rev. B 54, 14423 (1996)PRBMDO0163-182910.1103/PhysRevB.54.14423; Tian, Kamenev, and Larkin, Phys. Rev. Lett. 93, 124101 (2004)PRLTAO0031-900710.1103/PhysRevLett.93.124101] and is due to a delay in the onset of quantum interference effects, which occur sharply at a time of the order of the Ehrenfest time.

  18. Scaling exponents of the velocity structure functions in the interplanetary medium

    Directory of Open Access Journals (Sweden)

    V. Carbone

    Full Text Available We analyze the scaling exponents of the velocity structure functions, obtained from the velocity fluctuations measured in the interplanetary space plasma. Using the expression for the energy transfer rate which seems the most relevant in describing the evolution of the pseudo-energy densities in the interplanetary medium, we introduce an energy cascade model derived from a simple fragmentation process, which takes into account the intermittency effect. In the absence and in the presence of the large-scale magnetic field decorrelation effect the model reduces to the fluid and the hydromagnetic p-model, respectively. We show that the scaling exponents of the q-th power of the velocity structure functions, as obtained by the model in the absence of the decorrelation effect, furnishes the best-fit to the data analyzed from the Voyager 2 velocity field measurements at 8.5 AU. Our results allow us to hypothesize a new kind of scale-similarity for magnetohydrodynamic turbulence when the decorrelation effect is at work, related to the fourth-order velocity structure function.

  19. The path integral formulation of fractional Brownian motion for the general Hurst exponent

    International Nuclear Information System (INIS)

    Calvo, I; Sanchez, R

    2008-01-01

    In 1995, Sebastian (1995 J. Phys. A: Math. Gen. 28 4305) gave a path integral computation of the propagator of subdiffusive fractional Brownian motion (fBm), i.e. fBm with a Hurst or self-similarity exponent H element of (0, 1/2). The extension of Sebastian's calculation to superdiffusion, H element of (1/2, 1], becomes however quite involved due to the appearance of additional boundary conditions on fractional derivatives of the path. In this communication, we address the construction of the path integral representation in a different fashion, which allows us to treat both subdiffusion and superdiffusion on an equal footing. The derivation of the propagator of fBm for the general Hurst exponent is then performed in a neat and unified way. (fast track communication)

  20. Mental health inequalities in Slovenian 15-year-old adolescents explained by personal social position and family socioeconomic status.

    Science.gov (United States)

    Klanšček, Helena Jeriček; Ziberna, Janina; Korošec, Aleš; Zurc, Joca; Albreht, Tit

    2014-03-28

    Mental health inequalities are an increasingly important global problem. This study examined the association between mental health status and certain socioeconomic indicators (personal social position and the socioeconomic status of the family) in Slovenian 15-year-old adolescents. Data originate from the WHO-Collaborative cross-national 'Health Behavior in School-aged Children' study conducted in Slovenia in 2010 (1,815 secondary school pupils, aged 15). Mental health status was measured by: KIDSCREEN-10, the Strength and Difficulties questionnaire (SDQ), a life satisfaction scale, and one question about feelings of depression. Socioeconomic position was measured by the socioeconomic status of the family (Family Affluence Scale, perceived material welfare, family type, occupational status of parents) and personal social position (number of friends and the type of school). Logistic regression and a multivariate analysis of variance (MANOVA) were performed. Girls had 2.5-times higher odds of suffering feelings of depression (p mental health than those with a higher socioeconomic position. Because of the financial crisis, we can expect an increase in social inequalities and a greater impact on adolescents' mental health status in Slovenia in the future.

  1. Fractional Black–Scholes option pricing, volatility calibration and implied Hurst exponents in South African context

    Directory of Open Access Journals (Sweden)

    Emlyn Flint

    2017-03-01

    Full Text Available Background: Contingent claims on underlying assets are typically priced under a framework that assumes, inter alia, that the log returns of the underlying asset are normally distributed. However, many researchers have shown that this assumption is violated in practice. Such violations include the statistical properties of heavy tails, volatility clustering, leptokurtosis and long memory. This paper considers the pricing of contingent claims when the underlying is assumed to display long memory, an issue that has heretofore not received much attention. Aim: We address several theoretical and practical issues in option pricing and implied volatility calibration in a fractional Black–Scholes market. We introduce a novel eight-parameter fractional Black–Scholes-inspired (FBSI model for the implied volatility surface, and consider in depth the issue of calibration. One of the main benefits of such a model is that it allows one to decompose implied volatility into an independent long-memory component – captured by an implied Hurst exponent – and a conditional implied volatility component. Such a decomposition has useful applications in the areas of derivatives trading, risk management, delta hedging and dynamic asset allocation. Setting: The proposed FBSI volatility model is calibrated to South African equity index options data as well as South African Rand/American Dollar currency options data. However, given the focus on the theoretical development of the model, the results in this paper are applicable across all financial markets. Methods: The FBSI model essentially combines a deterministic function form of the 1-year implied volatility skew with a separate deterministic function for the implied Hurst exponent, thus allowing one to model both observed implied volatility surfaces as well as decompose them into independent volatility and long-memory components respectively. Calibration of the model makes use of a quasi-explicit weighted

  2. The Fermi-Pasta-Ulam Problem and Its Underlying Integrable Dynamics: An Approach Through Lyapunov Exponents

    Science.gov (United States)

    Benettin, G.; Pasquali, S.; Ponno, A.

    2018-05-01

    FPU models, in dimension one, are perturbations either of the linear model or of the Toda model; perturbations of the linear model include the usual β -model, perturbations of Toda include the usual α +β model. In this paper we explore and compare two families, or hierarchies, of FPU models, closer and closer to either the linear or the Toda model, by computing numerically, for each model, the maximal Lyapunov exponent χ . More precisely, we consider statistically typical trajectories and study the asymptotics of χ for large N (the number of particles) and small ɛ (the specific energy E / N), and find, for all models, asymptotic power laws χ ˜eq Cɛ ^a, C and a depending on the model. The asymptotics turns out to be, in general, rather slow, and producing accurate results requires a great computational effort. We also revisit and extend the analytic computation of χ introduced by Casetti, Livi and Pettini, originally formulated for the β -model. With great evidence the theory extends successfully to all models of the linear hierarchy, but not to models close to Toda.

  3. Singular elliptic systems involving concave terms and critical Caffarelli-Kohn-Nirenberg exponents

    Directory of Open Access Journals (Sweden)

    Mohammed E. O. El Mokhtar

    2012-03-01

    Full Text Available In this article, we establish the existence of at least four solutions to a singular system with a concave term, a critical Caffarelli-Kohn-Nirenberg exponent, and sign-changing weight functions. Our main tools are the Nehari manifold and the mountain pass theorem.

  4. Positive effects of a cognitive-behavioral intervention program for family caregivers of demented elderly

    Directory of Open Access Journals (Sweden)

    Patrícia Paes Araujo Fialho

    2012-10-01

    Full Text Available OBJECTIVE: It was to examine the effects of a Cognitive-Behavioral Therapy (CBT program administered to family caregivers of dementia patients. METHODS: Forty family caregivers were enrolled in a CBT intervention across eight weekly sessions. Cognitive, functional and behavioral status of patients were evaluated, as well as their own and their family caregivers' perceptions of quality of life. Specific instruments were also applied to evaluate caregiver stress level, coping, anxiety and depression. RESULTS: At the end of the program, family caregivers reported fewer neuropsychiatric symptoms among patients and an improvement in patients' quality of life. In addition, caregivers changed their coping strategies, whereas a significant decrease was observed in their anxiety levels. CONCLUSION: The CBT program employed appears to be a promising and useful tool for clinical practice, displaying positive effects on quality of life and neuropsychiatric symptoms of dementia, as well as proving beneficial for alleviating anxiety and stress in family caregivers.

  5. Phase Transitions, Geometrothermodynamics, and Critical Exponents of Black Holes with Conformal Anomaly

    Directory of Open Access Journals (Sweden)

    Jie-Xiong Mo

    2014-01-01

    Full Text Available We investigate the phase transitions of black holes with conformal anomaly in canonical ensemble. Some interesting and novel phase transition phenomena have been discovered. It is shown that there are striking differences in both Hawking temperature and phase structure between black holes with conformal anomaly and those without it. Moreover, we probe in detail the dependence of phase transitions on the choice of parameters. The results show that black holes with conformal anomaly have much richer phase structure than those without it. There would be two, only one, or no phase transition points depending on the parameters. The corresponding parameter regions are derived both numerically and graphically. Geometrothermodynamics are built up to examine the phase structure we have discovered. It is shown that Legendre invariant thermodynamic scalar curvature diverges exactly where the specific heat diverges. Furthermore, critical behaviors are investigated by calculating the relevant critical exponents. And we prove that these critical exponents satisfy the thermodynamic scaling laws.

  6. Anomalous roughness of turbulent interfaces with system size dependent local roughness exponent

    International Nuclear Information System (INIS)

    Balankin, Alexander S.; Matamoros, Daniel Morales

    2005-01-01

    In a system far from equilibrium the system size can play the role of control parameter that governs the spatiotemporal dynamics of the system. Accordingly, the kinetic roughness of interfaces in systems far from equilibrium may depend on the system size. To get an insight into this problem, we performed a detailed study of rough interfaces formed in paper combustion experiments. Using paper sheets of different width λ, we found that the turbulent flame fronts display anomalous multi-scaling characterized by non-universal global roughness exponent α and by the system size dependent spectrum of local roughness exponents, ζ q (λ)=ζ 1 (1)q -ω λ φ q =0.93q -0.15 . The structure factor of turbulent flame fronts also exhibits unconventional scaling dependence on λ. These results are expected to apply to a broad range of far from equilibrium systems when the kinetic energy fluctuations exceed a certain critical value.

  7. An Investigation of the Effectiveness of Family-Centred Positive Behaviour Support of Young Children with Disabilities

    Science.gov (United States)

    Chu, Szu-Yin

    2015-01-01

    Positive Behaviour Intervention and Support (PBIS) is an evidence-based approach that has been proven to be effective in remediating problem behaviours in children. The purpose of this study was to evaluate the effectiveness of the family-centred PBIS approach when involving Taiwanese families in the treatment of off-task and non-compliant…

  8. Nonlinearity exponent of ac conductivity in disordered systems

    International Nuclear Information System (INIS)

    Nandi, U N; Sircar, S; Karmakar, A; Giri, S

    2012-01-01

    We measured the real part of ac conductance Σ(x,f) or Σ(T,f) of iron-doped mixed-valent polycrystalline manganite oxides LaMn 1-x Fe x O 3 as a function of frequency f by varying initial conductance Σ 0 by quenched disorder x at a fixed temperature T (room) and by temperature T at a fixed quenched disorder x. At a fixed temperature T, Σ(x,f) of a sample with fixed x remains almost constant at its zero-frequency dc value Σ 0 at lower frequency. With increase in f, Σ(x,f) increases slowly from Σ 0 and finally increases rapidly following a power law with an exponent s at high frequency. Scaled appropriately, the data for Σ(T,f) and Σ(x,f) fall on the same universal curve, indicating the existence of a general scaling formalism for the ac conductivity in disordered systems. The characteristic frequency f c at which Σ(x,f) or Σ(T,f) increases for the first time from Σ 0 scales with initial conductance Σ 0 as f c ∼ Σ 0 x f , where x f is the onset exponent. The value of x f is nearly equal to one and is found to be independent of x and T. Further, an inverse relationship between x f and s provides a self-consistency check of the systematic description of Σ(x,f) or Σ(T,f). This apparent universal value of x f is discussed within the framework of existing theoretical models and scaling theories. The relevance to other similar disordered systems is also highlighted. (paper)

  9. Sensitivity of TDF and CRE to variations in exponents of N and T

    International Nuclear Information System (INIS)

    Orton, C.G.

    1976-01-01

    A typical example is given of the calculation by two methods of the value of the radiation dose given in 20 treatments at 5 fractions per week to be equivalent to 6000 rad given in 30 treatments also at 5 fractions per week. The solutions obtained were identical and demonstrated that, in normal clinical practice, whatever values are chosen for the exponents of N and T in the basic NSD equation, the CRE (Kirk, J., Gray, W.M., and Watson, E.R., 1971, Clinical Radiology, vol. 22, 145) and TDF (Orton, C.G., and Ellis, F., 1973, Br. J. Radiol., vol. 46, 529) methods are exactly equivalent. The variations in the values calculated by the TDF method of the dose/fraction in the same example for differing values of the exponents of N and T were typically less than +- 3%, and even for more drastic changes a variation of less than 5% resulted. The TDF and CRE methods are not therefore very sensitive to changes in these exponents. It is emphasized that since CREs are not linearly additive, application of the TDF method greatly reduces the probability of arithmetical error, particularly for more complex treatment regimes. The TDF method should however be applied with great caution if the time, dose or fractionation differ significantly from that used in conventional radiotherapeutic practice, since the theory was based on clinical evidence obtained by retrospective analysis of typical radiotherapy data. (U.K.)

  10. Sensitivity of TDF and CRE to variations in exponents of N and T

    Energy Technology Data Exchange (ETDEWEB)

    Orton, C G [Rhode Island Hospital, Providence (USA). Dept. of Radiation Oncology

    1976-10-01

    A typical example is given of the calculation by two methods of the value of the radiation dose given in 20 treatments at 5 fractions per week to be equivalent to 6000 rad given in 30 treatments also at 5 fractions per week. The solutions obtained were identical and demonstrated that, in normal clinical practice, whatever values are chosen for the exponents of N and T in the basic NSD equation, the CRE (Kirk, J., Gray, W.M., and Watson, E.R., 1971, Clinical Radiology, vol. 22, 145) and TDF (Orton, C.G., and Ellis, F., 1973, Br. J. Radiol., vol. 46, 529) methods are exactly equivalent. The variations in the values calculated by the TDF method of the dose/fraction in the same example for differing values of the exponents of N and T were typically less than +- 3%, and even for more drastic changes a variation of less than 5% resulted. The TDF and CRE methods are not therefore very sensitive to changes in these exponents. It is emphasized that since CREs are not linearly additive, application of the TDF method greatly reduces the probability of arithmetical error, particularly for more complex treatment regimes. The TDF method should however be applied with great caution if the time, dose or fractionation differ significantly from that used in conventional radiotherapeutic practice, since the theory was based on clinical evidence obtained by retrospective analysis of typical radiotherapy data.

  11. Effect of interband interaction on isotope effect exponent of MgB2 ...

    Indian Academy of Sciences (India)

    The interband interaction of the electron–phonon interaction shows more effect on the isotope exponent than on the non-phonon interaction. Acknowledgement. The authors would like to thank Thailand Research Fund for financial support and the University of the Thai Chamber of Commerce for partial financial support and.

  12. Lyapunov exponent as a metric for assessing the dynamic content and predictability of large-eddy simulations

    Science.gov (United States)

    Nastac, Gabriel; Labahn, Jeffrey W.; Magri, Luca; Ihme, Matthias

    2017-09-01

    Metrics used to assess the quality of large-eddy simulations commonly rely on a statistical assessment of the solution. While these metrics are valuable, a dynamic measure is desirable to further characterize the ability of a numerical simulation for capturing dynamic processes inherent in turbulent flows. To address this issue, a dynamic metric based on the Lyapunov exponent is proposed which assesses the growth rate of the solution separation. This metric is applied to two turbulent flow configurations: forced homogeneous isotropic turbulence and a turbulent jet diffusion flame. First, it is shown that, despite the direct numerical simulation (DNS) and large-eddy simulation (LES) being high-dimensional dynamical systems with O (107) degrees of freedom, the separation growth rate qualitatively behaves like a lower-dimensional dynamical system, in which the dimension of the Lyapunov system is substantially smaller than the discretized dynamical system. Second, a grid refinement analysis of each configuration demonstrates that as the LES filter width approaches the smallest scales of the system the Lyapunov exponent asymptotically approaches a plateau. Third, a small perturbation is superimposed onto the initial conditions of each configuration, and the Lyapunov exponent is used to estimate the time required for divergence, thereby providing a direct assessment of the predictability time of simulations. By comparing inert and reacting flows, it is shown that combustion increases the predictability of the turbulent simulation as a result of the dilatation and increased viscosity by heat release. The predictability time is found to scale with the integral time scale in both the reacting and inert jet flows. Fourth, an analysis of the local Lyapunov exponent is performed to demonstrate that this metric can also determine flow-dependent properties, such as regions that are sensitive to small perturbations or conditions of large turbulence within the flow field. Finally

  13. Momentum distribution critical exponents for one dimensional large U hubbard model in thermodynamic limit

    International Nuclear Information System (INIS)

    Qin Shaojin; Yu Lu.

    1996-03-01

    The critical exponent of the momentum distribution near k F , 3k F and 5k F are studied numerically for one-dimensional U → ∞ Hubbard model, using finite size systems and extrapolating them to the thermodynamic limit. Results at k F agree with earlier calculations, while at 3k F exponents less than 1 are obtained for finite size systems with extrapolation to 1 (regular behaviour) in the thermodynamic limit, in contrast to earlier analytic prediction 9/8. The distribution is regular at 5k F even for finite systems. The singularity near 3k F is interpreted as due to low energy excitations near 3k F in finite systems. (author). 18 refs, 4 figs, 1 tab

  14. Adiabatic invariants and asymptotic behavior of Lyapunov exponents of the Schrodinger equation

    International Nuclear Information System (INIS)

    Delyon, F.; Foulon, P.

    1986-01-01

    We give an upper bound for the high-energy behavior of the Lyapunov exponent of the one-dimensional Schrodinger equation. We relate this behavior to the diffrentiability properties of the potential. As an application, this result provides an upper bound for the asymptotic length of the gaps of the Schrodinger equation

  15. Effects on resilience of women family caregivers of adults with serious mental illness: the role of positive cognitions.

    Science.gov (United States)

    Zauszniewski, Jaclene A; Bekhet, Abir K; Suresky, M Jane

    2009-12-01

    This study examined the effects of risk and protective factors on resilience in 60 women family members of adults with serious mental illness. Both the risk factors constituting caregiver burden (strain, stigma, client dependence, and family disruption) and protective factors, including eight positive cognitions were found to predict two indicators of resilience: resourcefulness and sense of coherence. The effects of caregiver burden on resourcefulness and sense of coherence were mediated by positive cognitions, lending support to resilience theory and suggesting the need to develop interventions to encourage positive thinking among women caregivers of adults with mental illness.

  16. Correlates of HCV seropositivity among familial contacts of HCV positive patients

    Directory of Open Access Journals (Sweden)

    Matera Antonio

    2006-09-01

    Full Text Available Abstract Background Determinants of intrafamilial HCV transmission are still being debated. The aim of this study is to investigate the correlates of HCV seropositivity among familial contacts of HCV positive patients in Italy. Methods A cross-sectional study was conducted with 175 HCV positive patients (index cases, recruited from Policlinico Gemelli in Rome as well as other hospitals in Central Italy between 1995 and 2000 (40% female, mean age 57 ± 15.2 years, and 259 familial contacts. Differences in proportions of qualitative variables were tested with non-parametric tests (χ2, Yates correction, Fisher exact test, and a p value Results Seropositivity for HCV was found in 8.9% of the contacts. From the univariate analysis, risk factors significantly associated to HCV positivity in the contacts were: intravenous drug addiction (p = 0.004 and intercourse with drug addicts (p = 0.005. The only variables associated significantly and independently to HCV seropositivity in patients' contacts were intercourse with drug addicts (OR = 19.28; 95% CI: 2.01 – 184.94, the retirement status from work (OR = 3.76; 95% CI: 1.17 – 11.98, the time of the relationship (OR = 1.06; 95% CI: 1.00 – 1.11 and tattoos (OR = 7.68; 95% CI: 1.00 – 60.20. Conclusion The present study confirms that having intercourse with a drug addict is the most significant risk factor for intrafamilial HCV transmission. The association with retirement status from work could be related to both a long-term relationship with an index case and past exposure to common risk factors.

  17. The relationship between 19th century BMIs and family size: Economies of scale and positive externalities.

    Science.gov (United States)

    Carson, Scott Alan

    2015-04-01

    The use of body mass index values (BMI) to measure living standards is now a well-accepted method in economics. Nevertheless, a neglected area in historical studies is the relationship between 19th century BMI and family size, and this relationship is documented here to be positive. Material inequality and BMI are the subject of considerable debate, and there was a positive relationship between BMI and wealth and an inverse relationship with inequality. After controlling for family size and wealth, BMI values were related with occupations, and farmers and laborers had greater BMI values than workers in other occupations. Copyright © 2014 Elsevier GmbH. All rights reserved.

  18. Comment on 'Exact analytical solution for the generalized Lyapunov exponent of the two-dimensional Anderson localization'

    International Nuclear Information System (INIS)

    Markos, P; Schweitzer, L; Weyrauch, M

    2004-01-01

    In a recent publication, Kuzovkov et al (2002 J. Phys.: Condens. Matter. 14 13777) announced an analytical solution of the two-dimensional Anderson localization problem via the calculation of a generalized Lyapunov exponent using signal theory. Surprisingly, for certain energies and small disorder strength they observed delocalized states. We study the transmission properties of the same model using well-known transfer matrix methods. Our results disagree with the findings obtained using signal theory. We point to the possible origin of this discrepancy and comment on the general strategy of using a generalized Lyapunov exponent for studying Anderson localization. (comment)

  19. The Hausdorff dimension of random walks and the correlation length critical exponent in Euclidean field theory

    International Nuclear Information System (INIS)

    Kiskis, J.; Narayanan, R.; Vranas, P.

    1993-01-01

    The authors study the random walk representation of the two-point function in statistical mechanics models near the critical point. Using standard scaling arguments, the authors show that the critical exponent v describing the vanishing of the physical mass at the critical point is equal to v θ /d w , where d w is the Hausdorff dimension of the walk, and v θ = var-phi, where var-phi is the crossover exponent known in the context of field theory. This implies that the Hausdorff dimension of the walk is var-phi/v for O(N) models. 3 refs

  20. Invariant graphs of a family of non-uniformly expanding skew products over Markov maps

    Science.gov (United States)

    Walkden, C. P.; Withers, T.

    2018-06-01

    We consider a family of skew-products of the form where T is a continuous, expanding, locally eventually onto Markov map and is a family of homeomorphisms of . A function is said to be an invariant graph if is an invariant set for the skew-product; equivalently, u(T(x))  =  g x (u(x)). A well-studied problem is to consider the existence, regularity and dimension-theoretic properties of such functions, usually under strong contraction or expansion conditions (in terms of Lyapunov exponents or partial hyperbolicity) in the fibre direction. Here we consider such problems in a setting where the Lyapunov exponent in the fibre direction is zero on a set of periodic orbits but expands except on a neighbourhood of these periodic orbits. We prove that u either has the structure of a ‘quasi-graph’ (or ‘bony graph’) or is as smooth as the dynamics, and we give a criteria for this to happen.

  1. Positive Psychology and Familial Factors as Predictors of Latina/o Students' Psychological Grit

    Science.gov (United States)

    Vela, Javier C.; Lu, Ming-Tsan P.; Lenz, A. Stephen; Hinojosa, Karina

    2015-01-01

    Positive psychology is a useful framework to understand Latina/o students' experiences. In the current study, we examined how presence of meaning in life, search for meaning in life, hope, and family importance influenced 128 Latina/o college students' psychological grit. We used the Meaning in Life Questionnaire (MLQ), Subjective Happiness Scale,…

  2. Positive Family Intervention for Severe Challenging Behavior I: A Multisite Randomized Clinical Trial

    Science.gov (United States)

    Durand, V. Mark; Hieneman, Meme; Clarke, Shelley; Wang, Mo; Rinaldi, Melissa L.

    2013-01-01

    The present study was a multisite randomized clinical trial assessing the effects of adding a cognitive-behavioral intervention to positive behavior support (PBS). Fifty-four families who met the criteria of (a) having a child with a developmental disability, (b) whose child displayed serious challenging behavior (e.g., aggression, self-injury,…

  3. Application of the Lyapunov exponent to detect noise-induced chaos in oscillating microbial cultures

    International Nuclear Information System (INIS)

    Patnaik, P.R.

    2005-01-01

    Oscillating microbial processes can, under certain conditions, gravitate into chaotic behavior induced by external noise. Detection and control of chaos are important for the survival of the microorganisms and to operate a process usefully. In this study the largest Lyapunov exponent is recommended as a convenient and reliable index of chaos in continuous oscillating cultures. For the growth of Saccharomyces cerevisiae as a model system, the exponents increase with the oxygen mass transfer coefficient and decrease as the dilution rate increases. By comparing with the corresponding time-domain oscillations determined earlier, it is inferred that weakly oscillating cultures are less likely to be driven to chaotic behavior. The main carbon source, glucose, is quite robust to chaotic destabilization, thus enhancing its suitability as a manipulated variable for bioreactor control

  4. Truncatable bootstrap equations in algebraic form and critical surface exponents

    Energy Technology Data Exchange (ETDEWEB)

    Gliozzi, Ferdinando [Dipartimento di Fisica, Università di Torino andIstituto Nazionale di Fisica Nucleare - sezione di Torino,Via P. Giuria 1, Torino, I-10125 (Italy)

    2016-10-10

    We describe examples of drastic truncations of conformal bootstrap equations encoding much more information than that obtained by a direct numerical approach. A three-term truncation of the four point function of a free scalar in any space dimensions provides algebraic identities among conformal block derivatives which generate the exact spectrum of the infinitely many primary operators contributing to it. In boundary conformal field theories, we point out that the appearance of free parameters in the solutions of bootstrap equations is not an artifact of truncations, rather it reflects a physical property of permeable conformal interfaces which are described by the same equations. Surface transitions correspond to isolated points in the parameter space. We are able to locate them in the case of 3d Ising model, thanks to a useful algebraic form of 3d boundary bootstrap equations. It turns out that the low-lying spectra of the surface operators in the ordinary and the special transitions of 3d Ising model form two different solutions of the same polynomial equation. Their interplay yields an estimate of the surface renormalization group exponents, y{sub h}=0.72558(18) for the ordinary universality class and y{sub h}=1.646(2) for the special universality class, which compare well with the most recent Monte Carlo calculations. Estimates of other surface exponents as well as OPE coefficients are also obtained.

  5. Aging Wiener-Khinchin theorem and critical exponents of 1/f^{β} noise.

    Science.gov (United States)

    Leibovich, N; Dechant, A; Lutz, E; Barkai, E

    2016-11-01

    The power spectrum of a stationary process may be calculated in terms of the autocorrelation function using the Wiener-Khinchin theorem. We here generalize the Wiener-Khinchin theorem for nonstationary processes and introduce a time-dependent power spectrum 〈S_{t_{m}}(ω)〉 where t_{m} is the measurement time. For processes with an aging autocorrelation function of the form 〈I(t)I(t+τ)〉=t^{Υ}ϕ_{EA}(τ/t), where ϕ_{EA}(x) is a nonanalytic function when x is small, we find aging 1/f^{β} noise. Aging 1/f^{β} noise is characterized by five critical exponents. We derive the relations between the scaled autocorrelation function and these exponents. We show that our definition of the time-dependent spectrum retains its interpretation as a density of Fourier modes and discuss the relation to the apparent infrared divergence of 1/f^{β} noise. We illustrate our results for blinking-quantum-dot models, single-file diffusion, and Brownian motion in a logarithmic potential.

  6. Positive Emotional Effects of Leisure in Green Spaces in Alleviating Work–Family Spillover in Working Mothers

    Directory of Open Access Journals (Sweden)

    Po-Ju Chang

    2017-07-01

    Full Text Available Studies have shown that family and work spillover affects well-being and that leisure activities can alleviate the negative effects of work-related stress on health. However, few studies have focused on investigating the effects of specific leisure activities among specific populations. To examine whether leisure activities in green spaces can promote individual recovery processes and alleviate the effects of work and family spillover on positive emotions, this study applied the effort-recovery model to a population of working mothers. Through online and paper questionnaires, sample data were collected from 221 working mothers in Taiwan. Structural equation modeling was used to test the experimental hypothesis, and mediation analysis was used to determine whether leisure in green spaces is a mediating factor. The results indicated that leisure in green spaces is a mediator of the relationship of negative work and family spillover with positive emotions. In addition, strolls and park visits were found to provide greater psychological benefits to working mothers, compared with picnics.

  7. Positive Emotional Effects of Leisure in Green Spaces in Alleviating Work–Family Spillover in Working Mothers

    Science.gov (United States)

    Chang, Po-Ju; Bae, So Young

    2017-01-01

    Studies have shown that family and work spillover affects well-being and that leisure activities can alleviate the negative effects of work-related stress on health. However, few studies have focused on investigating the effects of specific leisure activities among specific populations. To examine whether leisure activities in green spaces can promote individual recovery processes and alleviate the effects of work and family spillover on positive emotions, this study applied the effort-recovery model to a population of working mothers. Through online and paper questionnaires, sample data were collected from 221 working mothers in Taiwan. Structural equation modeling was used to test the experimental hypothesis, and mediation analysis was used to determine whether leisure in green spaces is a mediating factor. The results indicated that leisure in green spaces is a mediator of the relationship of negative work and family spillover with positive emotions. In addition, strolls and park visits were found to provide greater psychological benefits to working mothers, compared with picnics. PMID:28696388

  8. Positive Emotional Effects of Leisure in Green Spaces in Alleviating Work-Family Spillover in Working Mothers.

    Science.gov (United States)

    Chang, Po-Ju; Bae, So Young

    2017-07-11

    Studies have shown that family and work spillover affects well-being and that leisure activities can alleviate the negative effects of work-related stress on health. However, few studies have focused on investigating the effects of specific leisure activities among specific populations. To examine whether leisure activities in green spaces can promote individual recovery processes and alleviate the effects of work and family spillover on positive emotions, this study applied the effort-recovery model to a population of working mothers. Through online and paper questionnaires, sample data were collected from 221 working mothers in Taiwan. Structural equation modeling was used to test the experimental hypothesis, and mediation analysis was used to determine whether leisure in green spaces is a mediating factor. The results indicated that leisure in green spaces is a mediator of the relationship of negative work and family spillover with positive emotions. In addition, strolls and park visits were found to provide greater psychological benefits to working mothers, compared with picnics.

  9. On the curve of critical exponents for nonlinear elliptic problems in the case of a zero mass

    Science.gov (United States)

    Il'yasov, Ya. Sh.

    2017-03-01

    For semilinear elliptic equations -Δ u = λ| u| p-2 u-| u| q-2 u, boundary value problems in bounded and unbounded domains are considered. In the plane of exponents p × q, the so-called curves of critical exponents are defined that divide this plane into domains with qualitatively different properties of the boundary value problems and the corresponding parabolic equations. New solvability conditions for boundary value problems, conditions for the stability and instability of stationary solutions, and conditions for the existence of global solutions to parabolic equations are found.

  10. Using largest Lyapunov exponent to confirm the intrinsic stability of boiling water reactors

    International Nuclear Information System (INIS)

    Gavilian-Moreno, Carlos; Espinosa-Paredes, Gilberto

    2016-01-01

    The aim of this paper is the study of instability state of boiling water reactors with a method based in largest Lyapunov exponents (LLEs). Detecting the presence of chaos in a dynamical system is an important problem that is solved by measuring the LLE. Lyapunov exponents quantify the exponential divergence of initially close state-space trajectories and estimate the amount of chaos in a system. This method was applied to a set of signals from several nuclear power plant (NPP) reactors under commercial operating conditions that experienced instabilities events, apparently each of a different nature. Laguna Verde and Forsmark NPPs with in-phase instabilities, and Cofrentes NPP with out-of-phases instability. This study presents the results of intrinsic instability in the boiling water reactors of three NPPs. In the analyzed cases the limit cycle was not reached, which implies that the point of equilibrium exerts influence and attraction on system evolution

  11. Using largest Lyapunov exponent to confirm the intrinsic stability of boiling water reactors

    Energy Technology Data Exchange (ETDEWEB)

    Gavilian-Moreno, Carlos [Iberdrola Generacion, S.A., Cofrentes Nuclear Power Plant, Project Engineering Department, Paraje le Plano S/N, Valencia (Spain); Espinosa-Paredes, Gilberto [Area de ingeniera en Recursos Energeticos, Universidad Autonoma Metropolitana-Iztapalapa, Mexico city (Mexico)

    2016-04-15

    The aim of this paper is the study of instability state of boiling water reactors with a method based in largest Lyapunov exponents (LLEs). Detecting the presence of chaos in a dynamical system is an important problem that is solved by measuring the LLE. Lyapunov exponents quantify the exponential divergence of initially close state-space trajectories and estimate the amount of chaos in a system. This method was applied to a set of signals from several nuclear power plant (NPP) reactors under commercial operating conditions that experienced instabilities events, apparently each of a different nature. Laguna Verde and Forsmark NPPs with in-phase instabilities, and Cofrentes NPP with out-of-phases instability. This study presents the results of intrinsic instability in the boiling water reactors of three NPPs. In the analyzed cases the limit cycle was not reached, which implies that the point of equilibrium exerts influence and attraction on system evolution.

  12. Using Largest Lyapunov Exponent to Confirm the Intrinsic Stability of Boiling Water Reactors

    Directory of Open Access Journals (Sweden)

    Carlos J. Gavilán-Moreno

    2016-04-01

    Full Text Available The aim of this paper is the study of instability state of boiling water reactors with a method based in largest Lyapunov exponents (LLEs. Detecting the presence of chaos in a dynamical system is an important problem that is solved by measuring the LLE. Lyapunov exponents quantify the exponential divergence of initially close state-space trajectories and estimate the amount of chaos in a system. This method was applied to a set of signals from several nuclear power plant (NPP reactors under commercial operating conditions that experienced instabilities events, apparently each of a different nature. Laguna Verde and Forsmark NPPs with in-phase instabilities, and Cofrentes NPP with out-of-phases instability. This study presents the results of intrinsic instability in the boiling water reactors of three NPPs. In the analyzed cases the limit cycle was not reached, which implies that the point of equilibrium exerts influence and attraction on system evolution.

  13. Socio-economic position, family demands and reported health in working men and women.

    Science.gov (United States)

    Regidor, Enrique; Pascual, Cruz; de la Fuente, Luis; Santos, Juana M; Astasio, Paloma; Ortega, Paloma

    2011-02-01

    This study evaluates the extent to which domestic workload explains socio-economic differences in poor self-reported health in women and men. In total, 6284 men and women who were employed and living with a partner were selected from the 2003 Spanish Health Interview Survey. The indicators of family demands investigated were person responsible for housework, number of persons in the household and the presence of at least one child under 15 years of age in the household. The measures of socio-economic position were educational level and household income, and the measures of health status were poor perceived health and limitation of activity due to disease. Household size and presence of a child under 15 in the home were not related with the measures of health status. The indicator about the person who does the housework was related with poor perceived health and with activity limitation. Specifically, the worst health status was seen in respondents who lived in homes where the partner or other family members did the housework. In general, the relation between indicators of socio-economic position and measures of health status was not modified after taking into account the person who does the housework. Among working people with a partner, persons who work and do their own housework do not have poorer perceived health than those living in homes where other people do the housework. This indicator of family demands does not explain the socio-economic differences in self-reported health.

  14. Associations of women's position in the household and food insecurity with family planning use in Nepal.

    Science.gov (United States)

    Diamond-Smith, Nadia; Raj, Anita; Prata, Ndola; Weiser, Sheri D

    2017-01-01

    Women in Nepal have low status, especially younger women in co-resident households. Nepal also faces high levels of household food insecurity and malnutrition, and stagnation in uptake of modern family planning methods. This study aims to understand if household structure and food insecurity interact to influence family planning use in Nepal. Using data on married, non-pregnant women aged 15-49 with at least one child from the Nepal 2011 Demographic and Health Survey (N = 7,460), we explore the relationship between women's position in the household, food insecurity as a moderator, and family planning use, using multi-variable logistic regressions. We adjust for household and individual factors, including other status-related variables. In adjusted models, living in a food insecure household and co-residing with in-laws either with no other daughter-in-laws or as the eldest or youngest daughter-in-law (compared to not-co-residing with in-laws) are all associated with lower odds of family planning use. In the interaction model, younger-sisters-in-law and women co-residing with no sisters-in-law in food insecure households have the lowest odds of family planning use. This study shows that household position is associated with family planning use in Nepal, and that food insecurity modifies these associations-highlighting the importance of considering both factors in understanding reproductive health care use in Nepal. Policies and programs should focus on the multiple pathways through which food insecurity impacts women's reproductive health, including focusing on women with the lowest status in households.

  15. Critical exponents of the transition from incoherence to partial oscillation death in the Winfree model

    International Nuclear Information System (INIS)

    Basnarkov, Lasko; Urumov, Viktor

    2009-01-01

    We consider an analytically solvable version of the Winfree model of synchronization of phase oscillators (proposed by Ariaratnam and Strogatz 2001 Phys. Rev. Lett. 86 4278). It is obtained that the transition from incoherence to a partial death state is characterized by third-order or higher phase transitions according to the Ehrenfest classification. The order of the transition depends on the shape of the distribution function for natural frequencies of oscillators in the vicinity of their lowest frequency. The corresponding critical exponents are found analytically and verified with numerical simulations of equations of motion. We also consider the generalized Winfree model with the interaction strength proportional to a power of the Kuramoto order parameter and find the domain where the critical exponent remains unchanged by this modification

  16. Cumulative Effective Hölder Exponent Based Indicator for Real-Time Fetal Heartbeat Analysis during Labour

    Science.gov (United States)

    Struzik, Zbigniew R.; van Wijngaarden, Willem J.

    We introduce a special purpose cumulative indicator, capturing in real time the cumulative deviation from the reference level of the exponent h (local roughness, Hölder exponent) of the fetal heartbeat during labour. We verify that the indicator applied to the variability component of the heartbeat coincides with the fetal outcome as determined by blood samples. The variability component is obtained from running real time decomposition of fetal heartbeat into independent components using an adaptation of an oversampled Haar wavelet transform. The particular filters used and resolutions applied are motivated by obstetricial insight/practice. The methodology described has the potential for real-time monitoring of the fetus during labour and for the prediction of the fetal outcome, allerting the attending staff in the case of (threatening) hypoxia.

  17. The effectiveness of cognitive behavioral stress management training on mental health, social interaction and family function in adolescents of families with one Human Immunodeficiency Virus (HIV) positive member.

    Science.gov (United States)

    Keypour, Maryam; Arman, Soroor; Maracy, Mohammad Reza

    2011-06-01

    This study evaluated stress management training to improve mental health, social interaction and family function among adolescents of families with one Human Immunodeficiency Virus (HIV) positive member. There were 34 adolescents (13-18 years old) with at least one family member living with HIV from whom finally 15 attended the study and participated in 8 weekly sessions of stress management training. The tests used in this study were: Strengths and Difficulties Questionnaire (self and parent report), General Health Questionnare-28 (GHQ-28) and Family Assessment Device (FAD), conducted before, after and three months after the intervention. The collected data were analyzed by repeated measure test using SPSS software (Version 18.0). Adolescents with one HIV positive family member showed high level of emotional problem (40%) and conduct problem (33.3%). There was a significant difference between before, after and 3months after intervention based on GHQ-28 mean scores and FAD mean sores (p social behavior based on SDQ (self report and parents report forms) in all three stages (before, after and three months after intervention). Stress management training is effective in improving mental health, family function and social interaction among adolescents living with parents infected with HIV/AIDS.

  18. Prevalence of a positive family history of type 2 diabetes in women with polycystic ovarian disease.

    Science.gov (United States)

    Fox, R

    1999-12-01

    The known association between insulin resistance and polycystic ovarian disease (PCOD) has been studied by determination of the prevalence of a positive family history of diabetes in a consecutive series of oligomenorrheic women with polycystic ovaries and eumenorrheic women with normal ovaries who served as controls. A significantly greater proportion of the families of the patients with PCOD had at least one member affected by type 2 diabetes (39.1% of the PCOD group and 7.6% of the controls; p PCOD had an increased prevalence of type 2 diabetes within their families. Paternal and maternal family members affected were in similar proportions, there being no evidence of preferential transmission through the female line in this study. The increased prevalence of type 2 diabetes in the families of women with polycystic ovaries is further evidence for the association between PCOD and insulin resistance, and provides a possible explanation for the familial nature of the ovarian disorder.

  19. Critical exponents for square lattice trails with a fixed number of vertices of degree 4

    International Nuclear Information System (INIS)

    James, E W; Soteros, C E

    2002-01-01

    We prove several previously conjectured results about the number of n-edge trails and n-edge embeddings of Eulerian graphs, each with a fixed number, k, of degree 4 vertices, in the lattice Z 2 . In particular, under the assumption that the relevant critical exponents exist, we prove that the difference between the critical exponent for closed trails (Eulerian graph embeddings) and that for self-avoiding circuits (polygons) is exactly k, the number of degree 4 vertices. Similarly, we prove that the difference between the critical exponent for either open trails or open Eulerian graph embeddings and that for self-avoiding walks is also k. These results are proved by establishing upper and lower bounds for the number of n-edge embeddings of closed (open) Eulerian graphs with k vertices of degree 4 in terms of the number of n-edge self-avoiding polygons (walks). The lower bounds are proved using a Kesten pattern theorem argument and the upper bounds are established by developing (based on a detailed case analysis) a method for removing vertices of degree 4 from an embedding by altering at most a constant (independent of n) number of vertices and edges of the embedding. The work presented here extends and improves the arguments first given in the work of Zhao and Lookman (1993 J. Phys. A: Math. Gen. 26 1067-76)

  20. Associations between positive parenting practices and child externalizing behavior in underserved Latino immigrant families.

    Science.gov (United States)

    Holtrop, Kendal; McNeil Smith, Sharde'; Scott, Jenna C

    2015-06-01

    This study examined whether five specific parenting practices (i.e., monitoring, discipline, skill encouragement, problem solving, and positive involvement) were associated with reduced child externalizing behaviors among a sample of Latino immigrant families. It utilized baseline data from 83 Latino couples with children participating in a larger randomized controlled trial of a culturally adapted parenting intervention. Results reveal that monitoring, discipline, skill encouragement, and problem solving each made independent contributions to the prediction of child externalizing behavior, although not all in the expected direction. Further analyses examining mothers and fathers separately suggest that mother-reported monitoring and father-reported discipline practices uniquely contributed to these findings. These results may have important implications for prevention and clinical intervention efforts with Latino immigrant families, including the cultural adaptation and implementation of parenting interventions with this underserved population. © 2014 Family Process Institute.

  1. Happy Family Kitchen II: a cluster randomized controlled trial of a community-based positive psychology family intervention for subjective happiness and health-related quality of life in Hong Kong.

    Science.gov (United States)

    Ho, Henry C Y; Mui, Moses; Wan, Alice; Ng, Yin-Lam; Stewart, Sunita M; Yew, Carol; Lam, Tai Hing; Chan, Sophia S

    2016-07-29

    Most positive psychology interventions conducted in the West have been focused on the individual. Family relationships are highly valued in the Chinese collectivist culture, and it is of interest to know whether family-focused interventions can improve the well-being of Chinese people. We have previously reported the effectiveness of a positive psychology family intervention in terms of family well-being. Based on the data derived from the Happy Family Kitchen II project, this paper examines the effectiveness of a community-based positive psychology family intervention on subjective happiness and health-related quality of life. Thirty-one social service units and schools organized intervention programs for 2070 participants in Hong Kong. In a cluster randomized controlled trial, participants were randomly assigned on the basis of computer-generated numbers into the intervention group or the control group. The intervention programs emphasized one of five positive psychology themes: joy, gratitude, flow, savoring, and listening. The control group engaged in activities unrelated to the intervention, such as arts and crafts workshops. Subjective happiness and mental and physical quality of life were assessed at baseline and at 4 weeks and 12 weeks postintervention. Data of 1261 participants were analyzed. The results showed that the intervention was more effective than the control condition in improving subjective happiness, with a small effect size, at 12 weeks postintervention (β = .15, p = .020, Cohen's d = .16). However, there were no improvements in mental and physical quality of life in the intervention group compared with the control group at 4 weeks (β = .39, p = .494, d = .05; β = -.10, p = 1.000, d = -.01, respectively) and 12 weeks postintervention (β = .71, p = .233, d = .08; β = -.05, p = 1.000, d = -.01, respectively). Furthermore, the booster session was no more effective than the tea

  2. Family income and young adolescents’ perceived social position: associations with self-esteem and life satisfaction in the UK Millennium Cohort Study

    Science.gov (United States)

    Bannink, Rienke; Pearce, Anna

    2016-01-01

    Background Self-esteem and life satisfaction are important aspects of positive mental health in young people, and both are socially distributed. However, the majority of evidence is based on socioeconomic characteristics of the family. As children enter adolescence and gain independence, perceptions of their own social position are likely to influence mental health. Design and objectives Using data on 11-year-olds from the UK Millennium Cohort Study, we investigated associations of both family income and young adolescents’ perception of their social position with self-esteem and life satisfaction. We hypothesised that there would be differences in the impact of perceived social position on positive mental health when investigating the full scale scoring distribution or the bottom of the distribution. Therefore, we estimated proportional odds for having greater positive mental health (across the distribution of scores) and ORs for poor outcomes (lowest 10% scores). Results The likelihood of greater self-esteem and life satisfaction increased with income; similarly, the risk of having poor self-esteem and life satisfaction increased as income decreased. Young adolescents who perceived their family as poorer than their friends (instead of about the same) were less likely to have greater self-esteem and life satisfaction and were more likely to have poor outcomes. Young adolescents who perceived their family as richer were more likely to have poor self-esteem, but were not less likely to have greater self-esteem. For life satisfaction, young adolescents who perceived their families as richer were less likely to have greater and more likely to have poor life satisfaction. Conclusions Policies to redistribute income in families with children are likely to benefit the mental health of young people. However, it is also important to consider the impact of social comparison on young people's mental health as they enter adolescence. PMID:26957529

  3. Zipf exponent of trajectory distribution in the hidden Markov model

    Science.gov (United States)

    Bochkarev, V. V.; Lerner, E. Yu

    2014-03-01

    This paper is the first step of generalization of the previously obtained full classification of the asymptotic behavior of the probability for Markov chain trajectories for the case of hidden Markov models. The main goal is to study the power (Zipf) and nonpower asymptotics of the frequency list of trajectories of hidden Markov frequencys and to obtain explicit formulae for the exponent of the power asymptotics. We consider several simple classes of hidden Markov models. We prove that the asymptotics for a hidden Markov model and for the corresponding Markov chain can be essentially different.

  4. Zipf exponent of trajectory distribution in the hidden Markov model

    International Nuclear Information System (INIS)

    Bochkarev, V V; Lerner, E Yu

    2014-01-01

    This paper is the first step of generalization of the previously obtained full classification of the asymptotic behavior of the probability for Markov chain trajectories for the case of hidden Markov models. The main goal is to study the power (Zipf) and nonpower asymptotics of the frequency list of trajectories of hidden Markov frequencys and to obtain explicit formulae for the exponent of the power asymptotics. We consider several simple classes of hidden Markov models. We prove that the asymptotics for a hidden Markov model and for the corresponding Markov chain can be essentially different

  5. Conditional Lyapunov exponents and transfer entropy in coupled bursting neurons under excitation and coupling mismatch

    Science.gov (United States)

    Soriano, Diogo C.; Santos, Odair V. dos; Suyama, Ricardo; Fazanaro, Filipe I.; Attux, Romis

    2018-03-01

    This work has a twofold aim: (a) to analyze an alternative approach for computing the conditional Lyapunov exponent (λcmax) aiming to evaluate the synchronization stability between nonlinear oscillators without solving the classical variational equations for the synchronization error dynamical system. In this first framework, an analytic reference value for λcmax is also provided in the context of Duffing master-slave scenario and precisely evaluated by the proposed numerical approach; (b) to apply this technique to the study of synchronization stability in chaotic Hindmarsh-Rose (HR) neuronal models under uni- and bi-directional resistive coupling and different excitation bias, which also considered the root mean square synchronization error, information theoretic measures and asymmetric transfer entropy in order to offer a better insight of the synchronization phenomenon. In particular, statistical and information theoretical measures were able to capture similarity increase between the neuronal oscillators just after a critical coupling value in accordance to the largest conditional Lyapunov exponent behavior. On the other hand, transfer entropy was able to detect neuronal emitter influence even in a weak coupling condition, i.e. under the increase of conditional Lyapunov exponent and apparently desynchronization tendency. In the performed set of numerical simulations, the synchronization measures were also evaluated for a two-dimensional parameter space defined by the neuronal coupling (emitter to a receiver neuron) and the (receiver) excitation current. Such analysis is repeated for different feedback couplings as well for different (emitter) excitation currents, revealing interesting characteristics of the attained synchronization region and conditions that facilitate the emergence of the synchronous behavior. These results provide a more detailed numerical insight of the underlying behavior of a HR in the excitation and coupling space, being in accordance

  6. Predicting the long tail of book sales: Unearthing the power-law exponent

    Science.gov (United States)

    Fenner, Trevor; Levene, Mark; Loizou, George

    2010-06-01

    The concept of the long tail has recently been used to explain the phenomenon in e-commerce where the total volume of sales of the items in the tail is comparable to that of the most popular items. In the case of online book sales, the proportion of tail sales has been estimated using regression techniques on the assumption that the data obeys a power-law distribution. Here we propose a different technique for estimation based on a generative model of book sales that results in an asymptotic power-law distribution of sales, but which does not suffer from the problems related to power-law regression techniques. We show that the proportion of tail sales predicted is very sensitive to the estimated power-law exponent. In particular, if we assume that the power-law exponent of the cumulative distribution is closer to 1.1 rather than to 1.2 (estimates published in 2003, calculated using regression by two groups of researchers), then our computations suggest that the tail sales of Amazon.com, rather than being 40% as estimated by Brynjolfsson, Hu and Smith in 2003, are actually closer to 20%, the proportion estimated by its CEO.

  7. Characterization of fish sauce aroma-impact compounds using GC-MS, SPME-Osme-GCO, and Stevens' power law exponents.

    Science.gov (United States)

    Pham, A J; Schilling, M W; Yoon, Y; Kamadia, V V; Marshall, D L

    2008-05-01

    The objectives of this study were to characterize volatile compounds and to determine the characteristic aromas associated with impact compounds in 4 fish sauces using solid-phase micro-extraction, gas chromatography-mass spectrometry, Osme, and gas chromatography olfactometry (SPME-Osme-GCO) coupled with Stevens' Power Law. Compounds were separated using GCMS and GCO and were identified with the mass spectral database, aroma perceived at the sniffing port, retention indices, and verification of compounds by authentic standards in the GCMS and GCO. Aromas that were isolated and present in all 4 fish sauce samples at all concentrations included fishy (trimethylamine), pungent and dirty socks (combination of butanoic, pentanoic, hexanoic, and heptanoic acids), cooked rice and buttery popcorn (2,6-dimethyl pyrazine), and sweet and cotton candy (benzaldehyde). All fish sauces contained the same aromas as determined by GCO and GCMS (verified using authentic standard compounds), but the odor intensity associated with each compound or group of compounds was variable for different fish sauce samples. Stevens' Power Law exponents were also determined using this analytical technique, but exponents were not consistent for the same compounds that were found in all fish sauces. Stevens' Power Law exponents ranged from 0.14 to 0.37, 0.24 to 0.34, 0.09 to 0.21, and 0.10 to 0.35 for dirty socks, fishy, buttery popcorn, and sweet aromas, respectively. This demonstrates that there is variability in Stevens' Power Law exponents for odorants within fish sauce samples.

  8. Dependence of exponents on text length versus finite-size scaling for word-frequency distributions

    Science.gov (United States)

    Corral, Álvaro; Font-Clos, Francesc

    2017-08-01

    Some authors have recently argued that a finite-size scaling law for the text-length dependence of word-frequency distributions cannot be conceptually valid. Here we give solid quantitative evidence for the validity of this scaling law, using both careful statistical tests and analytical arguments based on the generalized central-limit theorem applied to the moments of the distribution (and obtaining a novel derivation of Heaps' law as a by-product). We also find that the picture of word-frequency distributions with power-law exponents that decrease with text length [X. Yan and P. Minnhagen, Physica A 444, 828 (2016), 10.1016/j.physa.2015.10.082] does not stand with rigorous statistical analysis. Instead, we show that the distributions are perfectly described by power-law tails with stable exponents, whose values are close to 2, in agreement with the classical Zipf's law. Some misconceptions about scaling are also clarified.

  9. Efficacy of Positive Thinking Training on the Family Process and Subjective Wellbeing of Female Heads of Household

    Directory of Open Access Journals (Sweden)

    محمد خدایاری فرد

    2017-03-01

    Full Text Available The present study was designed to investigate the efficacy of positive thinking training on family process and subjective wellbeing of female heads of household. The method was a semi-experimental with pretest-posttest and control group; and the study population included all female heads of household residing in Chaharbagh, Alborz province, who have at least one primary school-kid.  Using available sampling method, 50 women were selected among school-students’ mothers, and were randomly assigned into two equal groups of experimental and control groups. Both groups filled Self-Report Family Process Scale (SFPS and Subjective Wellbeing Questionnaire (SWQ. The experimental group received positive thinking training for eight 2-hours-sessions. Then, all participants were assessed again as the posttest. The data were analyzed by covariance analysis method. Findings showed that after the intervention family process scores of experimental group had been significantly improved, while subjective wellbeing scores had not significantly enhanced. Therefore, it can be told that the present program was effective in increasing the family process, though it went ineffective in improving subjective wellbeing in these irritable individuals. Thus, altering and enriching the program and conducting further investigations seems necessary.

  10. Positive psychology outcome measures for family caregivers of people living with dementia: a systematic review

    NARCIS (Netherlands)

    Stansfeld, J.; Stoner, C.R.; Wenborn, J.; Vernooij-Dassen, M.J.F.J.; Moniz-Cook, E.; Orrell, M.

    2017-01-01

    BACKGROUND: Family caregivers of people living with dementia can have both positive and negative experiences of caregiving. Despite this, existing outcome measures predominately focus on negative aspects of caregiving such as burden and depression. This review aimed to evaluate the development and

  11. Family-of-Origin Factors and Partner Violence in the Intimate Relationships of Gay Men Who Are HIV Positive

    Science.gov (United States)

    Craft, Shonda M.; Serovich, Julianne M.

    2005-01-01

    This exploratory study examined the prevalence of intimate partner violence in a sample of gay men who are HIV positive. The concept of intergenerational transmission of violence, from family systems theory, provided the basis of this examination. It was hypothesized that men who had witnessed or experienced violence in their families of origin…

  12. Factors that enable nurse-patient communication in a family planning context: a positive deviance study.

    Science.gov (United States)

    Kim, Young Mi; Heerey, Michelle; Kols, Adrienne

    2008-10-01

    Family planning programmes in developing countries need a better understanding of nurse-patient communication in order to improve the quality of counselling. To identify factors in the clinic and in the community that enable nurses and patients to communicate effectively with one another. The study explored the personal experiences of nurses and patients who communicate especially effectively during family planning consultations (so-called "positive deviants"). Sixty-four randomly selected public clinics located in East Java, Indonesia. Seven positive deviant nurses and 32 positive deviant patients were identified from among 64 nurses and 768 patients who participated in an earlier patient coaching study. Flooding prevented 5 patients from participating in the study, reducing their number to 27. Investigators conducted: (1) a content analysis of qualitative data collected by structured in-depth interviews and focus-group discussions (FGDs) with positive deviant nurses and patients, and (2) analyses of variance (ANOVA) of quantitative data on clinic, nurse, and patient characteristics. Positive deviant nurses identified four factors, listed in rough order of importance, that helped them communicate effectively: independent study to strengthen their knowledge and skills; communication aids; feedback from colleagues; and motivation stemming from a desire to help people, patients' appreciation, husband's support, and increased income. Positive deviant patients identified five enabling factors: motivation due to their need for a service; confidence in their own communication skills; positive feedback from nurses; belief in patients' right and responsibility to communicate with nurses; and communication aids. Insights from positive deviant nurses and patients suggest that efforts to improve nurse-patient communication should go beyond conventional communication skills training. Managers should consider a mix of clinic-based interventions (such as peer feedback

  13. Error exponents for entanglement concentration

    International Nuclear Information System (INIS)

    Hayashi, Masahito; Koashi, Masato; Matsumoto, Keiji; Morikoshi, Fumiaki; Winter, Andreas

    2003-01-01

    Consider entanglement concentration schemes that convert n identical copies of a pure state into a maximally entangled state of a desired size with success probability being close to one in the asymptotic limit. We give the distillable entanglement, the number of Bell pairs distilled per copy, as a function of an error exponent, which represents the rate of decrease in failure probability as n tends to infinity. The formula fills the gap between the least upper bound of distillable entanglement in probabilistic concentration, which is the well-known entropy of entanglement, and the maximum attained in deterministic concentration. The method of types in information theory enables the detailed analysis of the distillable entanglement in terms of the error rate. In addition to the probabilistic argument, we consider another type of entanglement concentration scheme, where the initial state is deterministically transformed into a (possibly mixed) final state whose fidelity to a maximally entangled state of a desired size converges to one in the asymptotic limit. We show that the same formula as in the probabilistic argument is valid for the argument on fidelity by replacing the success probability with the fidelity. Furthermore, we also discuss entanglement yield when optimal success probability or optimal fidelity converges to zero in the asymptotic limit (strong converse), and give the explicit formulae for those cases

  14. Geodesic stability, Lyapunov exponents, and quasinormal modes

    International Nuclear Information System (INIS)

    Cardoso, Vitor; Miranda, Alex S.; Berti, Emanuele; Witek, Helvi; Zanchin, Vilson T.

    2009-01-01

    Geodesic motion determines important features of spacetimes. Null unstable geodesics are closely related to the appearance of compact objects to external observers and have been associated with the characteristic modes of black holes. By computing the Lyapunov exponent, which is the inverse of the instability time scale associated with this geodesic motion, we show that, in the eikonal limit, quasinormal modes of black holes in any dimensions are determined by the parameters of the circular null geodesics. This result is independent of the field equations and only assumes a stationary, spherically symmetric and asymptotically flat line element, but it does not seem to be easily extendable to anti-de Sitter spacetimes. We further show that (i) in spacetime dimensions greater than four, equatorial circular timelike geodesics in a Myers-Perry black-hole background are unstable, and (ii) the instability time scale of equatorial null geodesics in Myers-Perry spacetimes has a local minimum for spacetimes of dimension d≥6.

  15. Determination of the Lyapunov exponents and the information dimension in some dynamical systems

    International Nuclear Information System (INIS)

    Ziar, A.

    1992-01-01

    Classical phase space for some dynamical systems relevant in nuclear physics are studied. The nuclei is described by convex billiards or in the mean field theory. In both cases, besides the Poincare surface of sections which gives a qualitative description, each trajectory is characterized by its maximum Lyapunov exponent. The analytic monodromy matrix for a free particle in convex billiards rotating around an axis perpendicular to the plan of billiards, is determined, generalizing a previous result obtained for static billiards. In the frame of the mean field theory, it is shown an interesting alternative to the Lyapunov exponent, which is the dimension of the manifold in the phase space associated to the trajectory, leading to the evaluation of the relative chaotic volume in phase space as a function of the different parameters. The dimension appears as a character which could be determined easily for the rotating mean field, where the dimension of the manifold on which the trajectory is lying could be equal to 5 or 4 for chaotic trajectories, and less or equal to 3 for regular ones

  16. Relationship between deficiency of vitamin D and exponents of metabolic syndrome.

    Science.gov (United States)

    Kramkowska, M; Grzelak, T; Walczak, M; Bogdanski, P; Pupek-Musialik, D; Czyzewska, K

    2015-06-01

    Widespread hypovitaminosis D and an increased incidence of metabolic syndrome (MetS) represent significant problems of contemporary medicine but link between them remain unresolved. We aimed to define relationship between vitamin D serum concentration and exponents of MetS. The studies were conducted on 70 individuals (51 with and 19 without MetS). Concentrations of 25(OH)D (25-hydroxyergocalciferol and 25-hydroxycholecalciferol), calcium, cholesterol, HDL, cholesterol LDL, triglycerides, fasting glucose, blood pressure and anthropometric parameters were measured. Median concentration of vitamin D in the research population amounted to 41.46 nmol/L. Concentration of 25(OH)D in MetS group was lower than in remainder participants (38.45 nmol/L vs. 58.50 nmol/L, p = 0.0104). An inverse correlation was demonstrated between 25(OH)D level on one hand and body weight, waist and hips circumference, adipose body weight, Body Mass Index, Waist to Height Ratio (WHtR), glycaemia and number of MetS components on the other in persons free of MetS. No such relationships could be documented in MetS group. In the entire population values of Waist to Hip Ratio (WHpR) and WHtR indices manifested correlation with hyperglycaemia, hypertriglyceridaemia, low HDL concentrations. In persons without MetS a relationship was detected between vitamin D concentration and exponents of metabolic syndrome, although further studies on this problem are required.

  17. Work-family harmony

    OpenAIRE

    Adhikari,Pralhad

    2018-01-01

    The phenomenon of positively thinking about work and organization during the family hours by a worker is called work-family harmony. On the fag opposite of work-family conflict is work-family harmony. The work extends/intrudes into the family life of the worker, but in a positive way. This kind of positive thinking about the organization helps person's subjective well-being grow and his mental health is also nourished.

  18. Analysis of Multiple Structural Changes in Financial Contagion Based on the Largest Lyapunov Exponents

    Directory of Open Access Journals (Sweden)

    Rui Wang

    2014-01-01

    Full Text Available A modified multiple structural changes model is built to test structural breaks of the financial system based on calculating the largest Lyapunov exponents of the financial time series. Afterwards, the Lorenz system is used as a simulation example to inspect the new model. As the Lorenz system has strong nonlinearity, the verification results show that the new model has good capability in both finding the breakpoint and revealing the changes in nonlinear characteristics of the time series. The empirical study based on the model used daily data from the S&P 500 stock index during the global financial crisis from 2005 to 2012. The results provide four breakpoints of the period, which divide the contagion into four stages: stationary, local outbreak, global outbreak, and recovery period. An additional significant result is the obvious chaos characteristic difference in the largest Lyapunov exponents and the standard deviation at various stages, particularly at the local outbreak stage.

  19. Wilson's theory of critical phenomena. Higher order corrections to critical exponents

    International Nuclear Information System (INIS)

    Zinn-Justin, J.

    1973-01-01

    The Wilson's theory of critical phenomena is presented, in the context of renormalized field theory in d dimension and of the Callan-Symanzik equations. This theory allows in particular to compute critical exponents that govern the behavior of some correlation functions near the critical temperature, as power series in epsilon=4-d, using the standard perturbation theory. Owing to the large value of the expansion parameter epsilon, whose physical value is one, it is very important to perform higher order calculations [fr

  20. Generalized Hurst exponent approach to efficiency in MENA markets

    Science.gov (United States)

    Sensoy, A.

    2013-10-01

    We study the time-varying efficiency of 15 Middle East and North African (MENA) stock markets by generalized Hurst exponent analysis of daily data with a rolling window technique. The study covers a time period of six years from January 2007 to December 2012. The results reveal that all MENA stock markets exhibit different degrees of long-range dependence varying over time and that the Arab Spring has had a negative effect on market efficiency in the region. The least inefficient market is found to be Turkey, followed by Israel, while the most inefficient markets are Iran, Tunisia, and UAE. Turkey and Israel show characteristics of developed financial markets. Reasons and implications are discussed.

  1. The Hurst exponent over time: testing the assertion that emerging markets are becoming more efficient

    Science.gov (United States)

    Cajueiro, Daniel O.; Tabak, Benjamin M.

    2004-05-01

    This paper is concerned with the assertion found in the financial literature that emerging markets are becoming more efficient over time. To verify whether this assertion is true or not, we propose the calculation of the Hurst exponent over time using a time window with 4 years of data. The data used here comprises the bulk of emerging markets for Latin America and Asia. Our empirical results show that this assertion seems to be true for most countries, but it does not hold for countries such as Brazil, The Philippines and Thailand. Moreover, in order to check whether or not these results depend on the short term memory and the volatility of returns common in such financial asset return data, we filter the data by an AR-GARCH procedure and present the Hurst exponents for this filtered data.

  2. Perturbation theory for Lyapunov exponents of an Anderson model on a strip

    CERN Document Server

    Schulz-Baldes, H

    2003-01-01

    It is proven that the localization length of an Anderson model on a strip of width $L$ is bounded above by $L/\\lambda^2$ for small values of the coupling constant $\\lambda$ of the disordered potential. For this purpose, a new formalism is developed in order to calculate the bottom Lyapunov exponent associated with random products of large symplectic matrices perturbatively in the coupling constant of the randomness.

  3. Men’s and women’s position in the family in the context of social gender roles

    OpenAIRE

    Vargün, Berivan

    2016-01-01

    Men’s and Women’s positions in traditional families differ in the context of social gender roles. Identifying and analysing the socio-cultural values concerning gender roles transmitted down to individuals through teaching is important in that they demonstrate the status of traditional values and unwritten rules which are alive in societies today.  The study was conducted in the central quarters of Şanlıurfa and Batman cities. Firstly, men’s and women’s duties in a family, women’s positio...

  4. The feminist position on family planning in Spain.

    Science.gov (United States)

    Navarro, M V

    1984-04-01

    The Spanish feminist movement had its origins in the early 1970; in 1975 the first offical feminist conference made the following demands on the public authorities; 1) to abolish all sections of the Criminal Code which restrict women's freedom to control of their own bodies through making illegal information on and the purchase of contraceptives, 2) to decriminalize abortion, 3) to create family planning centers and to legalize contraceptives and provide them through the social security system, and 4) to include sex information in study courses. The distribution and sale of contraceptives was not legalized until 1978 and induced abortion is still a criminal offense. Nevertheless, after the 1975 meetins, a Coordinating Organization was established for the family planning committees that were functioning in the different feminist organizations. The problem of where to obtain contraceptives was solved by a group of feminist women which opened the 1st family planning center in Spain in 19779 This center was managed directly by members of the group. This and similar efforts culminated in the origin of the Movement for Movement for Family Planning that demanded in 1978; 1) the provision of sex information confronting the dominant sexual ideology and which is made a ccompulsory subject from school age, for both sexes; 2) free access to contraception for everyone; 3) the legalization of abortion, 4) the development of extensive information campaign on the problems of conception and contraception; and 5) the creation of independent, self-managed, family planning centers. There is now a Coordinating Organization of Family Planning Centers that was established in 1982. The socialist government is determined to create a public network of family planning centers.

  5. Family income and young adolescents' perceived social position: associations with self-esteem and life satisfaction in the UK Millennium Cohort Study.

    Science.gov (United States)

    Bannink, Rienke; Pearce, Anna; Hope, Steven

    2016-10-01

    Self-esteem and life satisfaction are important aspects of positive mental health in young people, and both are socially distributed. However, the majority of evidence is based on socioeconomic characteristics of the family. As children enter adolescence and gain independence, perceptions of their own social position are likely to influence mental health. Using data on 11-year-olds from the UK Millennium Cohort Study, we investigated associations of both family income and young adolescents' perception of their social position with self-esteem and life satisfaction. We hypothesised that there would be differences in the impact of perceived social position on positive mental health when investigating the full scale scoring distribution or the bottom of the distribution. Therefore, we estimated proportional odds for having greater positive mental health (across the distribution of scores) and ORs for poor outcomes (lowest 10% scores). The likelihood of greater self-esteem and life satisfaction increased with income; similarly, the risk of having poor self-esteem and life satisfaction increased as income decreased. Young adolescents who perceived their family as poorer than their friends (instead of about the same) were less likely to have greater self-esteem and life satisfaction and were more likely to have poor outcomes. Young adolescents who perceived their family as richer were more likely to have poor self-esteem, but were not less likely to have greater self-esteem. For life satisfaction, young adolescents who perceived their families as richer were less likely to have greater and more likely to have poor life satisfaction. Policies to redistribute income in families with children are likely to benefit the mental health of young people. However, it is also important to consider the impact of social comparison on young people's mental health as they enter adolescence. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted

  6. Using a Positive Psychology and Family Framework to Understand Mexican American Adolescents' College-Going Beliefs

    Science.gov (United States)

    Vela, Javier C.; Lenz, A. Stephen; Sparrow, Gregory Scott; Gonzalez, Stacey Lee

    2017-01-01

    Positive psychology is a useful framework to understand Mexican American adolescents' academic experiences. We used a quantitative, predictive design to explore how presence of meaning in life, search for meaning in life, subjective happiness, hope, and family importance influenced 131 Mexican American adolescents' college-going beliefs. We used…

  7. Dynamic dilution exponent in monodisperse entangled polymer solutions

    DEFF Research Database (Denmark)

    Shahid, T.; Huang, Qian; Oosterlinck, F.

    2017-01-01

    of concentration but also depends on the molar mass of the chains. While the proposed approach successfully explains the viscoelastic properties of a large number of semi-dilute solutions of polymers in their own oligomers, important discrepancies are found for semi-dilute entangled polymers in small-molecule......We study and model the linear viscoelastic properties of several entangled semi-dilute and concentrated solutions of linear chains of different molar masses and at different concentrations dissolved in their oligomers. We discuss the dilution effect of the oligomers on the entangled long chains....... In particular, we investigate the influence of both concentration and molar mass on the value of the effective dynamic dilution exponent determined from the level of the storage plateau at low and intermediate frequencies. We show that the experimental results can be quantitatively explained by considering...

  8. Abdominal aortic aneurysms do not develop more aggressively among patients with a positive family history of the disease

    DEFF Research Database (Denmark)

    Mejnert Jørgensen, Trine; Wemmelund, Holger; Green, Anders

    Title: Abdominal aortic aneurysms no not develop more aggressively among patients with a positive family history of the disease Authors: Trine M. M. Joergensen, Holger Wemmelund, Anders Green, Jes Lindholt, Kim Houlind. Introduction: It is well known, that a family history of abdominal aortic...... aneurysm (AAA) strongly increases the risk of developing AAA, but it is still uncertain whether familial AAA’s develops differently than non-familial AAA’s. Objectives: To investigate whether familial AAA’s develop more aggressively than non-familial AAA’s by looking at growth rate, risk of surgery...... and rupture, as well as the size of the aneurysm at the time of diagnosis and the patient´s age at the time of operation, rupture and diagnosis. Design: Observational retrospective longitudinal study Materials: 318 patients (273 men and 45 women) with AAA diagnosed between 1996-2008 in Jutland, Denmark...

  9. A new interpretation of zero Lyapunov exponents in BKL time for Mixmaster cosmology

    International Nuclear Information System (INIS)

    Wu Xin

    2010-01-01

    A global relationship between cosmological time and Belinskii-Khalatnikov-Lifshitz (BKL) time during the entire evolution of the Mixmaster Bianchi IX universe is used to explain why all the Lyapunov exponents are zero at the BKL time. The actual reason is that the domain of the cosmological time is finite as the BKL time runs from minus infinity to infinity.

  10. Positive Psychology and Familial Factors as Predictors of Latina/o Students' Hope and College Performance

    Science.gov (United States)

    Cavazos Vela, Javier; Lerma, Eunice; Lenz, A. Stephen; Hinojosa, Karina; Hernandez-Duque, Omar; Gonzalez, Stacey L.

    2014-01-01

    We investigated the contributions of positive psychology and familial factors as predictors of hope and academic performance among 166 Latina/o college students enrolled at a Hispanic Serving Institution of Higher Education. The results indicated that presence of meaning in life, search for meaning in life, daily spiritual experiences, and…

  11. The brief time-reversibility of the local Lyapunov exponents for a small chaotic Hamiltonian system

    International Nuclear Information System (INIS)

    Waldner, Franz; Hoover, William G.; Hoover, Carol G.

    2014-01-01

    Highlights: •We consider the local Lyapunov spectrum for a four-dimensional Hamilton system. •Its stable periodic motion can be reversed for long times. •In the chaotic motion, time reversal occurs only for a short time. •Perturbations will change this short unstable case into a different stable case. •These observations might relate chaos to the Second Law of Thermodynamics. - Abstract: We consider the local (instantaneous) Lyapunov spectrum for a four-dimensional Hamiltonian system. Its stable periodic motion can be reversed for long times. Its unstable chaotic motion, with two symmetric pairs of exponents, cannot. In the latter case reversal occurs for more than a thousand fourth-order Runge–Kutta time steps, followed by a transition to a new set of paired Lyapunov exponents, unrelated to those seen in the forward time direction. The relation of the observed chaotic dynamics to the Second Law of Thermodynamics is discussed

  12. Ramifications of ostracism as a consequence of revelation of HIV positive status: its effect o individuals and families in Botswana

    Directory of Open Access Journals (Sweden)

    Tabitha T. Langeni

    2003-12-01

    the structure and composition of the family in Botswana. The study showed that the highest proportion of respondents who would abandon an HIV positive partner (58.4% occurs among young people aged 15 to 19 years; and that the propensity to abandon an HIV positive partner diminishes with advancement in age. In-depth inquiries on why HIV positive partners would be abandoned produced responses that revolved around fear of exposure, vulnerability and association with an HIV positive individual. The study showed that the highest proportion of respondents who would not reveal their HIV positive status occurs among those who have lost a relative or a friend to AIDS. Fear of being isolated, rejected, stigmatized and unwanted featured among the top reasons why respondents would not reveal their HIV positive status. Society’s reaction towards HIV positive individuals and families with HIV/AIDS patients appeared strong enough to drive individuals to hide their positive status and to go ahead and take the risk of onward transmission of the virus.

  13. Asymptotic scaling properties and estimation of the generalized Hurst exponents in financial data

    Science.gov (United States)

    Buonocore, R. J.; Aste, T.; Di Matteo, T.

    2017-04-01

    We propose a method to measure the Hurst exponents of financial time series. The scaling of the absolute moments against the aggregation horizon of real financial processes and of both uniscaling and multiscaling synthetic processes converges asymptotically towards linearity in log-log scale. In light of this we found appropriate a modification of the usual scaling equation via the introduction of a filter function. We devised a measurement procedure which takes into account the presence of the filter function without the need of directly estimating it. We verified that the method is unbiased within the errors by applying it to synthetic time series with known scaling properties. Finally we show an application to empirical financial time series where we fit the measured scaling exponents via a second or a fourth degree polynomial, which, because of theoretical constraints, have respectively only one and two degrees of freedom. We found that on our data set there is not clear preference between the second or fourth degree polynomial. Moreover the study of the filter functions of each time series shows common patterns of convergence depending on the momentum degree.

  14. Influence of hydrogen-ion concentration exponent on undrained shear behaviour of bentonites; Bentonaito no hihaisui sendan kyodo ni oyobosu suiso ion nodo shisu no eikyo

    Energy Technology Data Exchange (ETDEWEB)

    Kamei, T [Kiso Jiban Consultants Co. Ltd., Tokyo (Japan); Tokida, M [Nagano National College of Technology, Nagano (Japan)

    1994-12-21

    Because there is a report example that the yield stress of a landslide clay increases along with a decrease of a hydrogen-ion concentration exponent, it is thought that a shear strength of the landslide clay depends on the hydrogen-ion concentration exponent. Furthermore, when the soil stabilization method by lime is applied to the soft ground and high organic earth, it is pointed out that the hydrogen-ion concentration exponent will become one of the harmful factors. Accordingly, it is understood that revealing an influence of a hydrogen-ion concentration exponent affects on the characteristics of an earth is one of the important factors, to evaluate a strength, deformation and so forth of the viscous ground. In this study, in order to examine an influence of a hydrogen-ion concentration exponent affecting on an undrained shear behavior of the bentonites, for the artificially adjusted bentonite specimens with 5 kinds of different pH, the isotropic consolidated undrained triaxial compression tests were performed, and consequently an influence of pH affecting on the engineering characteristics of the bentonites was made clear quantitatively. 28 refs., 16 figs., 5 tabs.

  15. Developmental Trajectories of Positive and Negative Affect in Children at High and Low Familial Risk for Depressive Disorder

    Science.gov (United States)

    Olino, Thomas M.; Lopez-Duran, Nestor L.; Kovacs, Maria; George, Charles J.; Gentzler, Amy L.; Shaw, Daniel S.

    2011-01-01

    Background: Although low positive affect (PA) and high negative affect (NA) have been posited to predispose to depressive disorders, little is known about the developmental trajectories of these affects in children at familial risk for mood disorders. Methods: We examined 202 offspring of mothers who had a history of juvenile-onset unipolar…

  16. Microscopic processes controlling the Herschel-Bulkley exponent

    Science.gov (United States)

    Lin, Jie; Wyart, Matthieu

    2018-01-01

    The flow curve of various yield stress materials is singular as the strain rate vanishes and can be characterized by the so-called Herschel-Bulkley exponent n =1 /β . A mean-field approximation due to Hebraud and Lequeux (HL) assumes mechanical noise to be Gaussian and leads to β =2 in rather good agreement with observations. Here we prove that the improved mean-field model where the mechanical noise has fat tails instead leads to β =1 with logarithmic correction. This result supports that HL is not a suitable explanation for the value of β , which is instead significantly affected by finite-dimensional effects. From considerations on elastoplastic models and on the limitation of speed at which avalanches of plasticity can propagate, we argue that β =1 +1 /(d -df) , where df is the fractal dimension of avalanches and d the spatial dimension. Measurements of df then supports that β ≈2.1 and β ≈1.7 in two and three dimensions, respectively. We discuss theoretical arguments leading to approximations of β in finite dimensions.

  17. The effectiveness of cognitive behavioral stress management training on mental health, social interaction and family function in adolescents of families with one Human Immunodeficiency Virus (HIV positive member

    Directory of Open Access Journals (Sweden)

    Maryam Keypour

    2011-01-01

    Full Text Available Background: This study evaluated stress management training to improve mental health, social interaction and family function among adolescents of families with one Human Immunodeficiency Virus (HIV positive member. Methods: There were 34 adolescents (13-18 years old with at least one family member living with HIV from whom finally 15 attended the study and participated in 8 weekly sessions of stress management training. The tests used in this study were: Strengths and Difficulties Questionnaire (self and parent report, General Health Questionnare-28 (GHQ-28 and Family Assessment Device (FAD, conducted before, after and three months after the intervention. The collected data were analyzed by repeated measure test using SPSS software (Version 18.0. Results: Adolescents with one HIV positive family member showed high level of emotional problem (40% and conduct problem (33.3%. There was a significant difference between before, after and 3months after intervention based on GHQ-28 mean scores and FAD mean sores (p < 0.001. There was a significant difference between mean scores of peers′ relationship based on SDQ (self report and parents report forms before and after intervention, but there was no significant difference between mean scores of pro social behavior based on SDQ (self report and parents report forms in all three stages (before, after and three months after intervention. Conclusions: Stress management training is effective in improving mental health, family function and social interaction among adolescents living with parents infected with HIV/AIDS.

  18. Positioning the expanded akirin gene family of Atlantic salmon within the transcriptional networks of myogenesis

    International Nuclear Information System (INIS)

    Macqueen, Daniel J.; Bower, Neil I.; Johnston, Ian A.

    2010-01-01

    Research highlights: → The expanded akirin gene family of Atlantic salmon was characterised. → akirin paralogues are regulated between mono- and multi-nucleated muscle cells. → akirin paralogues positioned within known genetic networks controlling myogenesis. → Co-expression of akirin paralogues is evident across cell types/during myogenesis. → Selection has likely maintained common regulatory elements among akirin paralogues. -- Abstract: Vertebrate akirin genes usually form a family with one-to-three members that regulate gene expression during the innate immune response, carcinogenesis and myogenesis. We recently established that an expanded family of eight akirin genes is conserved across salmonid fish. Here, we measured mRNA levels of the akirin family of Atlantic salmon (Salmo salar L.) during the differentiation of primary myoblasts cultured from fast-skeletal muscle. Using hierarchical clustering and correlation, the data was positioned into a network of expression profiles including twenty further genes that regulate myogenesis. akirin1(2b) was not significantly regulated during the maturation of the cell culture. akirin2(1a) and 2(1b), along with IGF-II and several igfbps, were most highly expressed in mononuclear cells, then significantly and constitutively downregulated as differentiation proceeded and myotubes formed/matured. Conversely, akirin1(1a), 1(1b), 1(2a), 2(2a) and 2(2b) were expressed at lowest levels when mononuclear cells dominated the culture and highest levels when confluent layers of myotubes were evident. However, akirin1(2a) and 2(2a) were first upregulated earlier than akirin1(1a), 1(1b) and 2(2b), when rates of myoblast proliferation were highest. Interestingly, akirin1(1b), 1(2a), 2(2a) and 2(2b) formed part of a module of co-expressed genes involved in muscle differentiation, including myod1a, myog, mef2a, 14-3-3β and 14-3-3γ. All akirin paralogues were expressed ubiquitously across ten tissues, although mRNA levels

  19. Positioning the expanded akirin gene family of Atlantic salmon within the transcriptional networks of myogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Macqueen, Daniel J., E-mail: djm59@st-andrews.ac.uk [Laboratory of Physiological and Evolutionary Genomics, Scottish Oceans Institute, University of St Andrews, St Andrews, Fife KY16 8LB (United Kingdom); Bower, Neil I., E-mail: nib@st-andrews.ac.uk [Laboratory of Physiological and Evolutionary Genomics, Scottish Oceans Institute, University of St Andrews, St Andrews, Fife KY16 8LB (United Kingdom); Johnston, Ian A., E-mail: iaj@st-andrews.ac.uk [Laboratory of Physiological and Evolutionary Genomics, Scottish Oceans Institute, University of St Andrews, St Andrews, Fife KY16 8LB (United Kingdom)

    2010-10-01

    Research highlights: {yields} The expanded akirin gene family of Atlantic salmon was characterised. {yields} akirin paralogues are regulated between mono- and multi-nucleated muscle cells. {yields} akirin paralogues positioned within known genetic networks controlling myogenesis. {yields} Co-expression of akirin paralogues is evident across cell types/during myogenesis. {yields} Selection has likely maintained common regulatory elements among akirin paralogues. -- Abstract: Vertebrate akirin genes usually form a family with one-to-three members that regulate gene expression during the innate immune response, carcinogenesis and myogenesis. We recently established that an expanded family of eight akirin genes is conserved across salmonid fish. Here, we measured mRNA levels of the akirin family of Atlantic salmon (Salmo salar L.) during the differentiation of primary myoblasts cultured from fast-skeletal muscle. Using hierarchical clustering and correlation, the data was positioned into a network of expression profiles including twenty further genes that regulate myogenesis. akirin1(2b) was not significantly regulated during the maturation of the cell culture. akirin2(1a) and 2(1b), along with IGF-II and several igfbps, were most highly expressed in mononuclear cells, then significantly and constitutively downregulated as differentiation proceeded and myotubes formed/matured. Conversely, akirin1(1a), 1(1b), 1(2a), 2(2a) and 2(2b) were expressed at lowest levels when mononuclear cells dominated the culture and highest levels when confluent layers of myotubes were evident. However, akirin1(2a) and 2(2a) were first upregulated earlier than akirin1(1a), 1(1b) and 2(2b), when rates of myoblast proliferation were highest. Interestingly, akirin1(1b), 1(2a), 2(2a) and 2(2b) formed part of a module of co-expressed genes involved in muscle differentiation, including myod1a, myog, mef2a, 14-3-3{beta} and 14-3-3{gamma}. All akirin paralogues were expressed ubiquitously across ten

  20. Family emotional expressiveness and family structure

    Directory of Open Access Journals (Sweden)

    Čotar-Konrad Sonja

    2016-01-01

    Full Text Available The present paper scrutinizes the relationship between family emotional expressiveness (i.e., the tendency to express dominant and/or submissive positive and negative emotions and components of family structure as proposed in Olson’s Circumplex model (i.e., cohesion and flexibility, family communication, and satisfaction in families with adolescents. The study was conducted on a sample of 514 Slovenian adolescents, who filled out two questionnaires: the Slovenian version of Family Emotional Expressiveness - FEQ and FACES IV. The results revealed that all four basic dimensions of family functioning were significantly associated with higher/more frequent expressions of positive submissive emotions, as well as with lower/less frequent expressions of negative dominant emotions. Moreover, expressions of negative submissive emotions explained a small, but significant amount of variance in three out of four family functioning variables (satisfaction, flexibility, and communication. The importance of particular aspects of emotional expressiveness for family cohesion, flexibility, communication, and satisfaction is discussed, and the relevance of present findings for family counselling is outlined.

  1. Critical behavior of the system of two crossing self-avoiding walks on a family of three-dimensional fractal lattices

    International Nuclear Information System (INIS)

    Zivic, I.; Elezovic-Hadzic, S.; Milosevic, S.

    2009-01-01

    We study the polymer system consisting of two-polymer chains situated in a fractal container that belongs to the three-dimensional Sierpinski Gasket (3D SG) family of fractals. The two-polymer system is modeled by two interacting self-avoiding walks (SAW) immersed in a good solvent. To conceive the inter-chain interactions we apply the model of two crossing self-avoiding walks (CSAW) in which the chains can cross each other. By applying renormalization group (RG) method, we establish the relevant phase diagrams for b=2 and b=3 members of the 3D SG fractal family. Also, at the appropriate transition fixed points we calculate the contact critical exponents φ, associated with the number of contacts between monomers of different chains. For larger b(2≤b≤30) we apply Monte Carlo renormalization group (MCRG) method, and compare the obtained results for φ with phenomenological proposals for the contact critical exponent, as well as with results obtained for other similar models of two-polymer system.

  2. An Emic, Mixed-Methods Approach to Defining and Measuring Positive Parenting among Low-Income Black Families

    Science.gov (United States)

    McWayne, Christine M.; Mattis, Jacqueline S.; Green Wright, Linnie E.; Limlingan, Maria Cristina; Harris, Elise

    2017-01-01

    Research Findings: This within-group exploratory sequential mixed-methods investigation sought to identify how ethnically diverse, urban-residing, low-income Black families conceptualize positive parenting. During the item development phase 119 primary caregivers from Head Start programs participated in focus groups and interviews. These…

  3. Effect of parameter calculation in direct estimation of the Lyapunov exponent in short time series

    Directory of Open Access Journals (Sweden)

    A. M. López Jiménez

    2002-01-01

    Full Text Available The literature about non-linear dynamics offers a few recommendations, which sometimes are divergent, about the criteria to be used in order to select the optimal calculus parameters in the estimation of Lyapunov exponents by direct methods. These few recommendations are circumscribed to the analysis of chaotic systems. We have found no recommendation for the estimation of λ starting from the time series of classic systems. The reason for this is the interest in distinguishing variability due to a chaotic behavior of determinist dynamic systems of variability caused by white noise or linear stochastic processes, and less in the identification of non-linear terms from the analysis of time series. In this study we have centered in the dependence of the Lyapunov exponent, obtained by means of direct estimation, of the initial distance and the time evolution. We have used generated series of chaotic systems and generated series of classic systems with varying complexity. To generate the series we have used the logistic map.

  4. Logotherapy and positive psychology

    Directory of Open Access Journals (Sweden)

    Oscar R. Oro

    2015-09-01

    Full Text Available Psychology omitted to approach, during almost a century, the positive aspects from persons, like creativity, humor, optimism, hope, forgiveness, life meaning, and happiness. These themes are approached by Positive Psychology, with Seligman like the principal exponent. Psychology was dedicated to explore the negative aspects from human beings improving human health. Nevertheless, this pathogenic model could not prevent mental disease. Concepts of Positive Psychology have a solid antecedent in Víktor Frankl ́s studies, which is the Logotherapy founder. This allows incorporating another perspective to approach positive aspects, from a philosophical and anthropological focus. Although the ways adopted by Frank and Seligman are different, both considered main aspects of human existence. Nevertheless, they investigated in different countries (from Europe and EE.UU.; in different circumstances (concentration camps, deaths, tortures; vs. academic context; in different historical periods and different social contexts (a country that lost the war and other that gave freedom to Europeans. In this work is used the concept life sense as the focus in professional formation and psychotherapy approach. 

  5. Phase space reconstruction and estimation of the largest Lyapunov exponent for gait kinematic data

    Energy Technology Data Exchange (ETDEWEB)

    Josiński, Henryk [Silesian University of Technology, Akademicka 16, 44-100 Gliwice (Poland); Świtoński, Adam [Polish-Japanese Institute of Information Technology, Aleja Legionów 2, 41-902 Bytom (Poland); Silesian University of Technology, Akademicka 16, 44-100 Gliwice (Poland); Michalczuk, Agnieszka; Wojciechowski, Konrad [Polish-Japanese Institute of Information Technology, Aleja Legionów 2, 41-902 Bytom (Poland)

    2015-03-10

    The authors describe an example of application of nonlinear time series analysis directed at identifying the presence of deterministic chaos in human motion data by means of the largest Lyapunov exponent. The method was previously verified on the basis of a time series constructed from the numerical solutions of both the Lorenz and the Rössler nonlinear dynamical systems.

  6. Applying the Nominal Response Model within a Longitudinal Framework to Construct the Positive Family Relationships Scale

    Science.gov (United States)

    Preston, Kathleen Suzanne Johnson; Parral, Skye N.; Gottfried, Allen W.; Oliver, Pamella H.; Gottfried, Adele Eskeles; Ibrahim, Sirena M.; Delany, Danielle

    2015-01-01

    A psychometric analysis was conducted using the nominal response model under the item response theory framework to construct the Positive Family Relationships scale. Using data from the Fullerton Longitudinal Study, this scale was constructed within a long-term longitudinal framework spanning middle childhood through adolescence. Items tapping…

  7. Critical exponents of a fluid mixture in the presence of isotope exchange: Isobutyric acid/D2O

    International Nuclear Information System (INIS)

    Gulari, E.; Chu, B.; Woermann, D.

    1980-01-01

    Experiments on phase diagrams and critical opalescence of a fluid mixture, isobutyric acid in D 2 O, indicate that the presence of isotope exchange reactions can change the critical behavior of such a system from that of a simple binary fluid mixture. Appreciable amounts of additional species due to isotope exchange distort the coexistence curve, shift the critical solution concentration y/sub c/ away from the concentration (y/sub I/*) where the maximal phase separation temperature T/sub p/,max occurs, and make the critical exponents γ and ν in the one-phase region (T>T/sub c/) different from those of the coexisting two-phase region (T 0 C differing from y/sub I/*=0.310 at T/sub p/,max=45.11 0 C. In the one-phase region, γ=1.25, ν=0.633, and xi 0 =3.13 A, in excellent agreement with γ=1.24 and ν=0.633 of simple fluid systems. However, in the coexisting two-phase region, the critical exponents appear to be renormalized with γ/sub x/ =1.39, ν/sub x/approx. =0.76, and xi 0 approx. =0.6 A. These results are in agreement with the renormalized critical exponents γ/sub x/=1.40 +- 0.02 and ν/sub x/ =0.73 +- 0.04 near the plait point of a ternary liquid mixture: ethanol--water--chloroform

  8. Family-of-Origin Factors and Partner Violence in the Intimate Relationships of Gay Men Who Are HIV Positive

    OpenAIRE

    CRAFT, SHONDA M.; SEROVICH, JULIANNE M.

    2005-01-01

    This exploratory study examined the prevalence of intimate partner violence in a sample of gay men who are HIV positive. The concept of intergenerational transmission of violence, from family systems theory, provided the basis of this examination. It was hypothesized that men who had witnessed or experienced violence in their families of origin would be more likely to perpetrate or experience violence in their intimate relationships. Perpetration and receipt of abuse were assessed to provide ...

  9. Quantifying the degree of persistence in random amoeboid motion based on the Hurst exponent of fractional Brownian motion.

    Science.gov (United States)

    Makarava, Natallia; Menz, Stephan; Theves, Matthias; Huisinga, Wilhelm; Beta, Carsten; Holschneider, Matthias

    2014-10-01

    Amoebae explore their environment in a random way, unless external cues like, e.g., nutrients, bias their motion. Even in the absence of cues, however, experimental cell tracks show some degree of persistence. In this paper, we analyzed individual cell tracks in the framework of a linear mixed effects model, where each track is modeled by a fractional Brownian motion, i.e., a Gaussian process exhibiting a long-term correlation structure superposed on a linear trend. The degree of persistence was quantified by the Hurst exponent of fractional Brownian motion. Our analysis of experimental cell tracks of the amoeba Dictyostelium discoideum showed a persistent movement for the majority of tracks. Employing a sliding window approach, we estimated the variations of the Hurst exponent over time, which allowed us to identify points in time, where the correlation structure was distorted ("outliers"). Coarse graining of track data via down-sampling allowed us to identify the dependence of persistence on the spatial scale. While one would expect the (mode of the) Hurst exponent to be constant on different temporal scales due to the self-similarity property of fractional Brownian motion, we observed a trend towards stronger persistence for the down-sampled cell tracks indicating stronger persistence on larger time scales.

  10. Hybrid Percolation Transition in Cluster Merging Processes: Continuously Varying Exponents

    Science.gov (United States)

    Cho, Y. S.; Lee, J. S.; Herrmann, H. J.; Kahng, B.

    2016-01-01

    Consider growing a network, in which every new connection is made between two disconnected nodes. At least one node is chosen randomly from a subset consisting of g fraction of the entire population in the smallest clusters. Here we show that this simple strategy for improving connection exhibits a more unusual phase transition, namely a hybrid percolation transition exhibiting the properties of both first-order and second-order phase transitions. The cluster size distribution of finite clusters at a transition point exhibits power-law behavior with a continuously varying exponent τ in the range 2 power-law behavior of the avalanche size distribution arising in models with link-deleting processes in interdependent networks.

  11. Rigorous lower bound on the dynamic critical exponent of some multilevel Swendsen-Wang algorithms

    International Nuclear Information System (INIS)

    Li, X.; Sokal, A.D.

    1991-01-01

    We prove the rigorous lower bound z exp ≥α/ν for the dynamic critical exponent of a broad class of multilevel (or ''multigrid'') variants of the Swendsen-Wang algorithm. This proves that such algorithms do suffer from critical slowing down. We conjecture that such algorithms in fact lie in the same dynamic universality class as the stanard Swendsen-Wang algorithm

  12. The use of the Hurst exponent to predict changes in trends on the Warsaw Stock Exchange

    Science.gov (United States)

    Domino, Krzysztof

    2011-01-01

    The local properties of the time series of the evolution of share prices of 126 significant companies traded on the Warsaw Stock Exchange during the period between 1991-2008 have been investigated. The analysis was applied to daily financial returns. I have used the local DFA to obtain the Hurst exponent (diffusion coefficient) while searching for negative correlations by which changes of long-term trends would be effected. A certain evidence, proving that after the signature of anti-correlation-the drop in the Hurst exponent-the change in the trend and in the return rate of an investment is probable, was pointed out. Hence after further investigation this method may be useful as a part of an investment strategy. As the Warsaw Stock Exchange is relatively smaller and younger than other significant world Stock Exchanges-and as the developing market is less efficient-the generalization for others markets needs further investigation.

  13. Relation Between Intelligence and Family Size, Position, and Income in Adolescent Girls in Saudi Arabia.

    Science.gov (United States)

    Osman, Habab; Alahmadi, Maryam; Bakhiet, Salaheldin; Lynn, Richard

    2016-12-01

    Data are reported showing statistically significant negative correlations between intelligence and family size, position, and income in a sample of 604 adolescent girls in Saudi Arabia. There were no statistically significant correlations or associations between whether the mother or father were deceased or both parents were alive, and whether the parents were living together or were divorced. © The Author(s) 2016.

  14. No differences in ventral striatum responsivity between adolescents with a positive family history of alcoholism and controls.

    Science.gov (United States)

    Müller, Kathrin U; Gan, Gabriela; Banaschewski, Tobias; Barker, Gareth J; Bokde, Arun L W; Büchel, Christian; Conrod, Patricia; Fauth-Bühler, Mira; Flor, Herta; Gallinat, Jürgen; Garavan, Hugh; Gowland, Penny; Heinz, Andreas; Ittermann, Bernd; Lawrence, Claire; Loth, Eva; Mann, Karl; Martinot, Jean-Luc; Nees, Frauke; Paus, Tomáš; Pausova, Zdenka; Rietschel, Marcella; Ströhle, Andreas; Struve, Maren; Schumann, Gunter; Smolka, Michael N

    2015-05-01

    Individuals with alcohol-dependent parents show an elevated risk of developing alcohol-related problems themselves. Modulations of the mesolimbic reward circuit have been postulated as a pre-existing marker of alcoholism. We tested whether a positive family history of alcoholism is correlated with ventral striatum functionality during a reward task. All participants performed a modified version of the monetary incentive delay task while their brain responses were measured with functional magnetic resonance imaging. We compared 206 healthy adolescents (aged 13-15) who had any first- or second-degree relative with alcoholism to 206 matched controls with no biological relative with alcoholism. Reward anticipation as well as feedback of win recruited the ventral striatum in all participants, but adolescents with a positive family history of alcoholism did not differ from their matched peers. Also we did not find any correlation between family history density and reward anticipation or feedback of win. This finding of no differences did not change when we analyzed a subsample of 77 adolescents with at least one parent with alcohol use disorder and their matched controls. Because this result is in line with another study reporting no differences between children with alcohol-dependent parents and controls at young age, but contrasts with studies of older individuals, one might conclude that at younger age the effect of family history has not yet exerted its influence on the still developing mesolimbic reward circuit. © 2014 Society for the Study of Addiction.

  15. The Ising model on a random planar lattice: The structure of the phase transition and the exact critical exponents

    International Nuclear Information System (INIS)

    Boulatov, D.V.; Kazakov, V.A.

    1987-01-01

    We investigate the critical properties of a recently proposed exactly soluble Ising model on a planar random dynamical lattice representing a regularization of the zero-dimensional string with internal fermions. The sum over all lattices gives rise to a new quantum degree of freedom - fluctuation of the metric. The whole system of critical exponents is found: α = -1, β = 1/2, γ = 2, δ = 5, v . D = 3. To test the universality we have used the planar graphs with the coordination number equal to 4 (Φ 4 theory graphs) as well as with the equal to 3 (Φ 3 theory graphs or triangulations). The critical exponents coincide for both cases. (orig.)

  16. Modulational estimate for the maximal Lyapunov exponent in Fermi-Pasta-Ulam chains

    Science.gov (United States)

    Dauxois, Thierry; Ruffo, Stefano; Torcini, Alessandro

    1997-12-01

    In the framework of the Fermi-Pasta-Ulam (FPU) model, we show a simple method to give an accurate analytical estimation of the maximal Lyapunov exponent at high energy density. The method is based on the computation of the mean value of the modulational instability growth rates associated to unstable modes. Moreover, we show that the strong stochasticity threshold found in the β-FPU system is closely related to a transition in tangent space, the Lyapunov eigenvector being more localized in space at high energy.

  17. The Hurst exponent in energy futures prices

    Science.gov (United States)

    Serletis, Apostolos; Rosenberg, Aryeh Adam

    2007-07-01

    This paper extends the work in Elder and Serletis [Long memory in energy futures prices, Rev. Financial Econ., forthcoming, 2007] and Serletis et al. [Detrended fluctuation analysis of the US stock market, Int. J. Bifurcation Chaos, forthcoming, 2007] by re-examining the empirical evidence for random walk type behavior in energy futures prices. In doing so, it uses daily data on energy futures traded on the New York Mercantile Exchange, over the period from July 2, 1990 to November 1, 2006, and a statistical physics approach-the ‘detrending moving average’ technique-providing a reliable framework for testing the information efficiency in financial markets as shown by Alessio et al. [Second-order moving average and scaling of stochastic time series, Eur. Phys. J. B 27 (2002) 197-200] and Carbone et al. [Time-dependent hurst exponent in financial time series. Physica A 344 (2004) 267-271; Analysis of clusters formed by the moving average of a long-range correlated time series. Phys. Rev. E 69 (2004) 026105]. The results show that energy futures returns display long memory and that the particular form of long memory is anti-persistence.

  18. Famiglia e geno-poiesi nel Nazionalsocialismo - Family and genos-poiesis in National Socialism

    Directory of Open Access Journals (Sweden)

    Alberto Castaldini

    2014-12-01

    Full Text Available The Nazi regime (1933-45 wanted to protect and promote through the creation of a new family structure the conservation of the biological heredity of the German nation, in order to preserve and refine obsessively the identity and the purity of the so-called Blutsgemeinschaft, the “community of blood” in which to identify the political and the cultural entity of the Volk, one of the pillars of Hitler’s biocracy. In the first half of the 20th century the value of memory, the nature of the family and the meaning of the relationship between the generations were manipulated and debased. This view, with its tragic ethical and juridical consequences, was scientifically warranted by German academic world, whose leading exponents took controversial positions. For instance the human biologist and eugenicist Otmar von Verschuer (1896-1969 theorized a biological unity between present and past, stating that the “German people is a large community of ancestors, namely a consanguineous solidarity”. In this way the Nazis deeply redefined the bonds of kinship and the genos assumed the nature of a “fictitious symbol” (C. Tullio-Altan in the service of a regime that in the name of an imaginary ancestral vitalism pursued a systematic policy of death.

  19. Pulling self-interacting linear polymers on a family of fractal lattices embedded in three-dimensional space

    International Nuclear Information System (INIS)

    Elezović-Hadžić, S; Živić, I

    2013-01-01

    We have studied the problem of force pulling self-interacting linear polymers situated in fractal containers that belong to the Sierpinski gasket (SG) family of fractals embedded in three-dimensional (3D) space. Each member of this family is labeled with an integer b (2 ≤ b ≤ ∞). The polymer chain is modeled by a self-avoiding walk (SAW) with one end anchored to one of the four boundary walls of the lattice, while the other (floating in the bulk of the fractal) is the position at which the force is acting. By applying an exact renormalization group (RG) method we have established the phase diagrams, including the critical force–temperature dependence, for fractals with b = 2,3 and 4. Also, for the same fractals, in all polymer phases, we examined the generating function G 1 for the numbers of all possible SAWs with one end anchored to the boundary wall. We found that besides the usual power-law singularity of G 1 , governed by the critical exponent γ 1 , whose specific values are worked out for all cases studied, in some regimes the function G 1 displays an essential singularity in its behavior. (paper)

  20. An exploration of socioeconomic, spiritual, and family support among HIV-positive women in India.

    Science.gov (United States)

    Majumdar, Basanti

    2004-01-01

    Through in-depth, tape-recorded interviews, this qualitative pilot study explored the feelings and concerns of 10 HIV-positive women, aged 18 to 70 years, and the socioeconomic, spiritual, and family support available to them in Kolkata, India. A qualitative approach of continuous comparative analysis of themes revealed that although heterosexual contact was the main source of infection, poverty and sexual violence were indirect social factors. These women experienced markedly less socioeconomic, spiritual, and family support after contracting the disease. In addition to worsening physical symptoms, emotional and mental anguish forced them into isolation, negatively affecting their mental health. Social isolation infiltrated their spiritual lives, producing feelings of helplessness about the future of their children. The identification of this process is important to nursing practice, as it highlights key areas of concern in the implementation of prevention programs and future research.

  1. Automatic detection of ischemic stroke based on scaling exponent electroencephalogram using extreme learning machine

    Science.gov (United States)

    Adhi, H. A.; Wijaya, S. K.; Prawito; Badri, C.; Rezal, M.

    2017-03-01

    Stroke is one of cerebrovascular diseases caused by the obstruction of blood flow to the brain. Stroke becomes the leading cause of death in Indonesia and the second in the world. Stroke also causes of the disability. Ischemic stroke accounts for most of all stroke cases. Obstruction of blood flow can cause tissue damage which results the electrical changes in the brain that can be observed through the electroencephalogram (EEG). In this study, we presented the results of automatic detection of ischemic stroke and normal subjects based on the scaling exponent EEG obtained through detrended fluctuation analysis (DFA) using extreme learning machine (ELM) as the classifier. The signal processing was performed with 18 channels of EEG in the range of 0-30 Hz. Scaling exponents of the subjects were used as the input for ELM to classify the ischemic stroke. The performance of detection was observed by the value of accuracy, sensitivity and specificity. The result showed, performance of the proposed method to classify the ischemic stroke was 84 % for accuracy, 82 % for sensitivity and 87 % for specificity with 120 hidden neurons and sine as the activation function of ELM.

  2. The Effects of Aesthetic Science Activities on Improving At-Risk Families Children's Anxiety About Learning Science and Positive Thinking

    Science.gov (United States)

    Hong, Zuway-R.; Lin, Huann-shyang; Chen, Hsiang-Ting; Wang, Hsin-Hui; Lin, Chia-Jung

    2014-01-01

    The purpose of this study was to explore the effects of aesthetic science activities on improving elementary school at-risk families' children's positive thinking, attitudes toward science, and decreasing their anxiety about learning science. Thirty-six 4th-grade children from at-risk families volunteered to participate in a 12-week intervention and formed the experimental group; another 97 typical 4th graders were randomly selected to participant in the assessment and were used as the comparison group. The treatment for experimental group children emphasized scaffolding aesthetic science activities and inquiry strategies. The Elementary School Student Questionnaire was administered to assess all children's positive thinking, attitudes toward science, and anxiety about learning science. In addition, nine target children from the experimental group with the lowest scores on either positive thinking, or attitudes toward science, or with the highest scores on anxiety about learning science in the pre-test were recruited to be interviewed at the end of the intervention and observed weekly. Confirmatory factor analyses, analyses of covariance, and content theme analysis assessed the similarities and differences between groups. It was found that the at-risk families' children were motivated by the treatment and made significant progress on positive thinking and attitudes toward science, and also decreased their anxiety about learning science. The findings from interviews and classroom observations also revealed that the intervention made differences in children's affective perceptions of learning science. Implication and research recommendation are discussed.

  3. Absence of positive solutions to the system of differential inequalities on manifolds

    Science.gov (United States)

    Sun, Yuhua

    2018-01-01

    We investigate the nonexistence of positive solutions to a certain system of differential inequalities on a complete connected non-compact Riemannian manifold. We show that if for some reference point x0, the volume of geodesic ball μ(B(x0, r)) ≤ Crp ln q r holds for all large enough r and for some constant C, then there exists no positive solution to the system. Here the exponents p and q are sharp and cannot be relaxed.

  4. Extraction of the power law exponent for 1 GeV/nucleon Au + C projectile multifragmentation

    International Nuclear Information System (INIS)

    Gilkes, M.L.; Elliott, J.B.; Huager, A.; Hirsch, A.S.; Hjort, E.

    1993-01-01

    Using moments of the measured charge distribution in exclusive gold multifragmentation events, we present a preliminary determination of the power law exponent τ. For a system undergoing a phase transition near the critical point, τ governs the cluster size distribution and is expected on rather general grounds to lie in the range 2 < τ < 3

  5. Clinic Attendance for Antiretroviral Pills Pick-Up among HIV-Positive People in Nepal: Roles of Perceived Family Support and Associated Factors.

    Science.gov (United States)

    Ayer, Rakesh; Kikuchi, Kimiyo; Ghimire, Mamata; Shibanuma, Akira; Pant, Madhab Raj; Poudel, Krishna C; Jimba, Masamine

    2016-01-01

    HIV-positive people's clinic attendance for medication pick-up is critical for successful HIV treatment. However, limited evidence exists on it especially in low-income settings such as Nepal. Moreover, the role of family support in clinic attendance remains under-explored. Therefore, this study was conducted to examine the association between perceived family support and regular clinic attendance and to assess factors associated with regular clinic attendance for antiretroviral pills pick-up among HIV-positive individuals in Nepal. A cross-sectional study was conducted among 423 HIV-positive people in three districts of Nepal. Clinic attendance was assessed retrospectively for the period of 12 months. To assess the factors associated, an interview survey was conducted using a semi-structured questionnaire from July to August, 2015. Multiple logistic regression models were used to assess the factors associated with regular clinic attendance. Of 423 HIV-positive people, only 32.6% attended the clinics regularly. They were more likely to attend them regularly when they received high family support (AOR = 3.98, 95% CI = 2.29, 6.92), participated in support programs (AOR = 1.68, 95% CI = 1.00, 2.82), and had knowledge on the benefits of antiretroviral therapy (AOR = 2.62, 95% CI = 1.15, 5.99). In contrast, they were less likely to attend them regularly when they commuted more than 60 minutes to the clinics (AOR = 0.53, 95% CI = 0.30, 0.93), when they self-rated their health status as being very good (AOR = 0.13, 95% CI = 0.04, 0.44), good (AOR = 0.14, 95% CI = 0.04, 0.46), and fair (AOR = 0.21, 95% CI = 0.06, 0.70). HIV-positive individuals are more likely to attend the clinics regularly when they receive high family support, know the benefits of antiretroviral therapy, and participate in support programs. To improve clinic attendance, family support should be incorporated with HIV care programs in resource limited settings. Service providers should also consider

  6. Clinic Attendance for Antiretroviral Pills Pick-Up among HIV-Positive People in Nepal: Roles of Perceived Family Support and Associated Factors

    Science.gov (United States)

    Kikuchi, Kimiyo; Ghimire, Mamata; Shibanuma, Akira; Pant, Madhab Raj; Poudel, Krishna C.; Jimba, Masamine

    2016-01-01

    Introduction HIV-positive people’s clinic attendance for medication pick-up is critical for successful HIV treatment. However, limited evidence exists on it especially in low-income settings such as Nepal. Moreover, the role of family support in clinic attendance remains under-explored. Therefore, this study was conducted to examine the association between perceived family support and regular clinic attendance and to assess factors associated with regular clinic attendance for antiretroviral pills pick-up among HIV-positive individuals in Nepal. Methods A cross-sectional study was conducted among 423 HIV-positive people in three districts of Nepal. Clinic attendance was assessed retrospectively for the period of 12 months. To assess the factors associated, an interview survey was conducted using a semi-structured questionnaire from July to August, 2015. Multiple logistic regression models were used to assess the factors associated with regular clinic attendance. Results Of 423 HIV-positive people, only 32.6% attended the clinics regularly. They were more likely to attend them regularly when they received high family support (AOR = 3.98, 95% CI = 2.29, 6.92), participated in support programs (AOR = 1.68, 95% CI = 1.00, 2.82), and had knowledge on the benefits of antiretroviral therapy (AOR = 2.62, 95% CI = 1.15, 5.99). In contrast, they were less likely to attend them regularly when they commuted more than 60 minutes to the clinics (AOR = 0.53, 95% CI = 0.30, 0.93), when they self-rated their health status as being very good (AOR = 0.13, 95% CI = 0.04, 0.44), good (AOR = 0.14, 95% CI = 0.04, 0.46), and fair (AOR = 0.21, 95% CI = 0.06, 0.70). Conclusion HIV-positive individuals are more likely to attend the clinics regularly when they receive high family support, know the benefits of antiretroviral therapy, and participate in support programs. To improve clinic attendance, family support should be incorporated with HIV care programs in resource limited settings

  7. Evaluating Noise Sensitivity on the Time Series Determination of Lyapunov Exponents Applied to the Nonlinear Pendulum

    Directory of Open Access Journals (Sweden)

    L.F.P. Franca

    2003-01-01

    Full Text Available This contribution presents an investigation on noise sensitivity of some of the most disseminated techniques employed to estimate Lyapunov exponents from time series. Since noise contamination is unavoidable in cases of data acquisition, it is important to recognize techniques that could be employed for a correct identification of chaos. State space reconstruction and the determination of Lyapunov exponents are carried out to investigate the response of a nonlinear pendulum. Signals are generated by numerical integration of the mathematical model, selecting a single variable of the system as a time series. In order to simulate experimental data sets, a random noise is introduced in the signal. Basically, the analyses of periodic and chaotic motions are carried out. Results obtained from mathematical model are compared with the one obtained from time series analysis, evaluating noise sensitivity. This procedure allows the identification of the best techniques to be employed in the analysis of experimental data.

  8. Familial risks and estrogen receptor-positive breast cancer in Hong Kong Chinese women.

    Science.gov (United States)

    Tse, Lap Ah; Li, Mengjie; Chan, Wing-cheong; Kwok, Chi-hei; Leung, Siu-lan; Wu, Cherry; Yu, Ignatius Tak-sun; Yu, Wai-cho; Lao, Xiangqian; Wang, Xiaorong; Wong, Carmen Ka-man; Lee, Priscilla Ming-yi; Wang, Feng; Yang, Xiaohong Rose

    2015-01-01

    The role of family history to the risk of breast cancer was analyzed by incorporating menopausal status in Hong Kong Chinese women, with a particular respect to the estrogen receptor-positive (ER+) type. Seven hundred and forty seven breast cancer incident cases and 781 hospital controls who had completed information on family cancer history in first-degree relatives (nature father, mother, and siblings) were recruited. Odds ratio for breast cancer were calculated by unconditional multiple logistic regression, stratified by menopausal status (a surrogate of endogenous female sex hormone level and age) and type of relative affected with the disease. Further subgroup analysis by tumor type according to ER status was investigated. Altogether 52 (6.96%) breast cancer cases and 23 (2.95%) controls was found that the patients' one or more first-degree relatives had a history of breast cancer, showing an adjusted odds ratio (OR) of 2.41 (95%CI: 1.45-4.02). An excess risk of breast cancer was restricted to the ER+ tumor (OR = 2.43, 95% CI: 1.38-4.28), with a relatively higher risk associated with an affected mother (OR = 3.97, 95%CI: 1.46-10.79) than an affected sister (OR = 2.06, 95%CI: 1.07-3.97), while the relative risk was more prominent in the subgroup of pre-menopausal women. Compared with the breast cancer overall, the familial risks to the ER+ tumor increased progressively with the number of affected first-degree relatives. This study provides new insights on a relationship between family breast cancer history, menopausal status, and the ER+ breast cancer. A separate risk prediction model for ER+ tumor in Asian population is desired.

  9. Positive and negative effects of family involvement on work-related burnout

    NARCIS (Netherlands)

    Brummelhuis, Lieke L. ten; Lippe, Tanja van der; Kluwer, Esther S.; Flap, Henk

    2008-01-01

    We aimed to explain the influence of family involvement on feelings of burnout among employees who combine work and family tasks. As proxies for family involvement, we used the family structure (partner, number and age of children) and family tasks (e.g. hours spent on household chores). We compared

  10. Relation Between Hertz Stress-Life Exponent, Ball-Race Conformity, and Ball Bearing Life

    Science.gov (United States)

    Zaretsky, Erwin V.; Poplawski, Joseph V.; Root, Lawrence E.

    2008-01-01

    ANSI/ABMA and ISO standards based on Lundberg-Palmgren bearing life theory are normalized for ball bearings having inner- and outerrace conformities of 52 percent (0.52) and made from pre-1940 bearing steel. The Lundberg-Palmgren theory incorporates an inverse 9th power relation between Hertz stress and fatigue life for ball bearings. The effect of race conformity on ball set life independent of race life is not incorporated into the Lundberg-Palmgren theory. In addition, post-1960 vacuum-processed bearing steel exhibits a 12th power relation between Hertz stress and life. The work reported extends the previous work of Zaretsky, Poplawski, and Root to calculate changes in bearing life--that includes the life of the ball set--caused by race conformity, Hertz stress-life exponent, ball bearing type and bearing series. The bearing fatigue life in actual application will usually be equal to or greater than that calculated using the ANSI/ABMA and ISO standards that incorporate the Lundberg-Palmgren theory. The relative fatigue life of an individual race is more sensitive to changes in race conformity for Hertz stress-life exponent n of 12 than where n = 9. However, when the effects are combined to predict actual bearing life for a specified set of conditions and bearing geometry, the predicted life of the bearing will be greater for a value of n = 12 than n = 9.

  11. Moment Lyapunov Exponent and Stochastic Stability of Binary Airfoil under Combined Harmonic and Non-Gaussian Colored Noise Excitations

    Science.gov (United States)

    Hu, D. L.; Liu, X. B.

    Both periodic loading and random forces commonly co-exist in real engineering applications. However, the dynamic behavior, especially dynamic stability of systems under parametric periodic and random excitations has been reported little in the literature. In this study, the moment Lyapunov exponent and stochastic stability of binary airfoil under combined harmonic and non-Gaussian colored noise excitations are investigated. The noise is simplified to an Ornstein-Uhlenbeck process by applying the path-integral method. Via the singular perturbation method, the second-order expansions of the moment Lyapunov exponent are obtained, which agree well with the results obtained by the Monte Carlo simulation. Finally, the effects of the noise and parametric resonance (such as subharmonic resonance and combination additive resonance) on the stochastic stability of the binary airfoil system are discussed.

  12. The relation between mass-gap amplitudes and critical exponents in the Heisenberg model

    International Nuclear Information System (INIS)

    Alcaraz, F.C.; Felicio, J.R.D. de

    1985-01-01

    A recent result concerning the universality of the ratio of mass-gap amplitudes using the well known 1-D Heisenberg model which is the quantum version of the two-dimensional eight-vertex model is discussed. The believed extended scaling relation (x sub(p) = x sub(is an element of)/4) relating the polarization and energy anomalous dimensions is confirmed. The exponent, α, ν, γ sub(m) and γ sub(p) is also obtained by usual phenomenological renormalization group methods. (Author) [pt

  13. Change in the family food environment is associated with positive dietary change in children.

    Science.gov (United States)

    Hendrie, Gilly; Sohonpal, Gundeep; Lange, Kylie; Golley, Rebecca

    2013-01-07

    The family food environment is an important influence in the development of children's dietary habits. Research suggests that influences of current dietary behaviour and behaviour change may differ. The aims of this paper were to: (1) investigate the association between the food environment at baseline and change in children's saturated fat intake; and (2) to explore whether a change in the food environment was associated with a change in children's saturated fat intake. Secondary analysis of a 12 week cluster randomised controlled trial in 133 4-13 year old children. Families were randomly allocated to parental education regarding changing to reduced-fat dairy foods or a comparison non-dietary behaviour. The interventions were family focused. Parents received education from a dietitian in 3x30 minute sessions to facilitate behaviour change. Parents completed a comprehensive questionnaire capturing three domains of the food environment--Parent knowledge and attitudes; shaping practices; and behaviours and role modelling. Children's dietary intake was assessed via multiple 24-hour recalls at baseline and week 12. Changes in the family food environment and primary outcome (saturated fat) were calculated. Hierarchical linear regression models were performed to explore the association between baseline and change in food environment constructs and change in saturated fat intake. Standardised Beta are presented (pchange in saturated fat. An increase in nutrition knowledge (β=-0.2), perceived responsibility (β=-0.3) and restriction (β=-0.3) from baseline to week 12 were associated with greater reduction in saturated fat intake. The present study was one of the first to quantify changes in the family food environment, and identify a number of factors which were associated with a positive dietary change. Because interventions focus on behaviour change, the findings may provide specific targets for intervention strategies in the future. Australia New Zealand Clinical

  14. The roles of gene duplication, gene conversion and positive selection in rodent Esp and Mup pheromone gene families with comparison to the Abp family.

    Science.gov (United States)

    Karn, Robert C; Laukaitis, Christina M

    2012-01-01

    Three proteinaceous pheromone families, the androgen-binding proteins (ABPs), the exocrine-gland secreting peptides (ESPs) and the major urinary proteins (MUPs) are encoded by large gene families in the genomes of Mus musculus and Rattus norvegicus. We studied the evolutionary histories of the Mup and Esp genes and compared them with what is known about the Abp genes. Apparently gene conversion has played little if any role in the expansion of the mouse Class A and Class B Mup genes and pseudogenes, and the rat Mups. By contrast, we found evidence of extensive gene conversion in many Esp genes although not in all of them. Our studies of selection identified at least two amino acid sites in β-sheets as having evolved under positive selection in the mouse Class A and Class B MUPs and in rat MUPs. We show that selection may have acted on the ESPs by determining K(a)/K(s) for Exon 3 sequences with and without the converted sequence segment. While it appears that purifying selection acted on the ESP signal peptides, the secreted portions of the ESPs probably have undergone much more rapid evolution. When the inner gene converted fragment sequences were removed, eleven Esp paralogs were present in two or more pairs with K(a)/K(s) >1.0 and thus we propose that positive selection is detectable by this means in at least some mouse Esp paralogs. We compare and contrast the evolutionary histories of all three mouse pheromone gene families in light of their proposed functions in mouse communication.

  15. A super-family of transcriptional activators regulates bacteriophage packaging and lysis in Gram-positive bacteria

    Science.gov (United States)

    Quiles-Puchalt, Nuria; Tormo-Más, María Ángeles; Campoy, Susana; Toledo-Arana, Alejandro; Monedero, Vicente; Lasa, Íñigo; Novick, Richard P.; Christie, Gail E.; Penadés, José R.

    2013-01-01

    The propagation of bacteriophages and other mobile genetic elements requires exploitation of the phage mechanisms involved in virion assembly and DNA packaging. Here, we identified and characterized four different families of phage-encoded proteins that function as activators required for transcription of the late operons (morphogenetic and lysis genes) in a large group of phages infecting Gram-positive bacteria. These regulators constitute a super-family of proteins, here named late transcriptional regulators (Ltr), which share common structural, biochemical and functional characteristics and are unique to this group of phages. They are all small basic proteins, encoded by genes present at the end of the early gene cluster in their respective phage genomes and expressed under cI repressor control. To control expression of the late operon, the Ltr proteins bind to a DNA repeat region situated upstream of the terS gene, activating its transcription. This involves the C-terminal part of the Ltr proteins, which control specificity for the DNA repeat region. Finally, we show that the Ltr proteins are the only phage-encoded proteins required for the activation of the packaging and lysis modules. In summary, we provide evidence that phage packaging and lysis is a conserved mechanism in Siphoviridae infecting a wide variety of Gram-positive bacteria. PMID:23771138

  16. Familial risks and estrogen receptor-positive breast cancer in Hong Kong Chinese women.

    Directory of Open Access Journals (Sweden)

    Lap Ah Tse

    Full Text Available The role of family history to the risk of breast cancer was analyzed by incorporating menopausal status in Hong Kong Chinese women, with a particular respect to the estrogen receptor-positive (ER+ type.Seven hundred and forty seven breast cancer incident cases and 781 hospital controls who had completed information on family cancer history in first-degree relatives (nature father, mother, and siblings were recruited. Odds ratio for breast cancer were calculated by unconditional multiple logistic regression, stratified by menopausal status (a surrogate of endogenous female sex hormone level and age and type of relative affected with the disease. Further subgroup analysis by tumor type according to ER status was investigated.Altogether 52 (6.96% breast cancer cases and 23 (2.95% controls was found that the patients' one or more first-degree relatives had a history of breast cancer, showing an adjusted odds ratio (OR of 2.41 (95%CI: 1.45-4.02. An excess risk of breast cancer was restricted to the ER+ tumor (OR = 2.43, 95% CI: 1.38-4.28, with a relatively higher risk associated with an affected mother (OR = 3.97, 95%CI: 1.46-10.79 than an affected sister (OR = 2.06, 95%CI: 1.07-3.97, while the relative risk was more prominent in the subgroup of pre-menopausal women. Compared with the breast cancer overall, the familial risks to the ER+ tumor increased progressively with the number of affected first-degree relatives.This study provides new insights on a relationship between family breast cancer history, menopausal status, and the ER+ breast cancer. A separate risk prediction model for ER+ tumor in Asian population is desired.

  17. Influence of granulometry in the Hurst exponent of air liquid interfaces formed during capillary rising in a granular media

    Directory of Open Access Journals (Sweden)

    Gontijo Guilherme L.

    2017-01-01

    Full Text Available We report results concerning the fractal dimension of a air/fluid interface formed during the capillary rising of a fluid into a dense granular media. The system consists in a modified Hele-Shaw cell filled with grains at different granulometries and confined in a narrow gap between the glass plates. The system is then placed onto a water reservoir, and the liquid penetrates the medium due to capillary forces. We measure the Hurst exponent of the liquid/air interface with help of image processing, and follow the temporal evolution of the profiles. We observe that the Hurst exponent can be related with the granulometry, but the range of values are odd to the predicted values from models or theory.

  18. Rethinking Family Patriarchy and Women's Positions in Presocialist China

    Science.gov (United States)

    Zuo, Jiping

    2009-01-01

    Grounded in the patrilineal family system in presocialist China, this study explores the intersection between generation and gender dimensions of family patriarchy in influencing marital power relations. Data come from the life stories of 80 elderly married individuals, collected during the 2000-2001 period in the city of Beijing. Patterns of male…

  19. All in the family: Work-family enrichment and crossover among farm couples.

    Science.gov (United States)

    Sprung, Justin M; Jex, Steve M

    2017-04-01

    This study expands upon the contextualization of the work-family interface by examining positive work-family experiences within the farming industry. Both individual and crossover effects were examined among a sample of 217 married farm couples. Results demonstrated multiple significant relationships between self-reported attitudes, work-family enrichment, and health outcomes. In addition, crossover effects reveal the importance of individual attitudes (husband work engagement and wife farm satisfaction) for spousal work-family enrichment and health outcomes. Furthermore, individual work-family enrichment was positively related to spousal psychological health and negatively related to spousal physical symptoms. Many of these findings remained significant after controlling for work-family conflict. Overall, our results suggest the potential beneficial impact of the integrated work-family dynamic associated with the farming profession for positive work-family experiences. Implications of these findings, as well as directions for future research, are discussed. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  20. Connection of optimum temporal exponents with a principle of least action

    Science.gov (United States)

    Sergeev, E. V.; Karzanov, A. V.; Tremaskin, A. V.

    2008-06-01

    The principle of the least action states, that the motion of objects on optimum trajectories conjugates to the underload expenditure of activity. In the canonical approach this statement is reduced to searching extreme activity. For the immediate proof of the underload expenditure of activity on optimum trajectories the relevant mathematical algorithm in the basis of which bottom the concept of optimum time exponents lays is offered. Using this algorithm, various modes of a motion of charged particles are explored: the harmonic motion, a motion in the homogeneous force field, a motion in a central force field and a motion on inertia. The terrain clearance minimum under the rate of flux of activity for the harmonic motions is detected.

  1. Mother-Child Positivity and Negativity: Family-Wide and Child-Specific Main Effects and Interactions Predict Child Adjustment

    Science.gov (United States)

    Oliver, Bonamy R.; Pike, Alison

    2018-01-01

    Links between positive and negative aspects of the parent-child relationship and child adjustment are undisputed. Scholars recognize the importance of parental differential treatment (PDT) of siblings, yet, less is known about PDT in the context of the shared (family-wide) parent-child relationship climate, or about the extent to which positivity…

  2. Nature of protein family signatures: insights from singular value analysis of position-specific scoring matrices.

    Directory of Open Access Journals (Sweden)

    Akira R Kinjo

    Full Text Available Position-specific scoring matrices (PSSMs are useful for detecting weak homology in protein sequence analysis, and they are thought to contain some essential signatures of the protein families. In order to elucidate what kind of ingredients constitute such family-specific signatures, we apply singular value decomposition to a set of PSSMs and examine the properties of dominant right and left singular vectors. The first right singular vectors were correlated with various amino acid indices including relative mutability, amino acid composition in protein interior, hydropathy, or turn propensity, depending on proteins. A significant correlation between the first left singular vector and a measure of site conservation was observed. It is shown that the contribution of the first singular component to the PSSMs act to disfavor potentially but falsely functionally important residues at conserved sites. The second right singular vectors were highly correlated with hydrophobicity scales, and the corresponding left singular vectors with contact numbers of protein structures. It is suggested that sequence alignment with a PSSM is essentially equivalent to threading supplemented with functional information. In addition, singular vectors may be useful for analyzing and annotating the characteristics of conserved sites in protein families.

  3. Family-of-Origin Factors and Partner Violence in the Intimate Relationships of Gay Men Who Are HIV Positive

    Science.gov (United States)

    SEROVICH, JULIANNE M.

    2005-01-01

    This exploratory study examined the prevalence of intimate partner violence in a sample of gay men who are HIV positive. The concept of intergenerational transmission of violence, from family systems theory, provided the basis of this examination. It was hypothesized that men who had witnessed or experienced violence in their families of origin would be more likely to perpetrate or experience violence in their intimate relationships. Perpetration and receipt of abuse were assessed to provide a more comprehensive examination of these relationships. The results of this study indicated that psychological abuse was the most commonly reported form of violence in these relationships. The results also provided partial support for the hypothesized relationship between family-of-origin violence and subsequent violence in an intimate relationship. Implications for future research and intervention are discussed. PMID:15914700

  4. A Family Focused Randomized Controlled Trial to Prevent Adolescent Alcohol and Tobacco Use: The Moderating Roles of Positive Parenting and Adolescent Gender

    Science.gov (United States)

    Jones, Deborah J.; Olson, Ardis L.; Forehand, Rex; Gaffney, Cecelia A.; Zens, Michael S.; Bau, J. J.

    2005-01-01

    Four years of longitudinal data from 2,153 families with a 5th- or 6th-grade preadolescent participating in a family-focused pediatric primary-care-based prevention program were used to examine whether prevention effects were moderated by positive parenting and/or adolescent gender. Alcohol and tobacco use, internalizing problems, and…

  5. The first experimental confirmation of the fractional kinetics containing the complex-power-law exponents: Dielectric measurements of polymerization reactions

    Science.gov (United States)

    Nigmatullin, R. R.; Arbuzov, A. A.; Salehli, F.; Giz, A.; Bayrak, I.; Catalgil-Giz, H.

    2007-01-01

    For the first time we achieved incontestable evidence that the real process of dielectric relaxation during the polymerization reaction of polyvinylpyrrolidone (PVP) is described in terms of the fractional kinetic equations containing complex-power-law exponents. The possibility of the existence of the fractional kinetics containing non-integer complex-power-law exponents follows from the general theory of dielectric relaxation that has been suggested recently by one of the authors (R.R.N). Based on the physical/geometrical meaning of the fractional integral with complex exponents there is a possibility to develop a general theory of dielectric relaxation based on the self-similar (fractal) character of the reduced (averaged) microprocesses that take place in the mesoscale region. This theory contains some essential predictions related to existence of the non-integer power-law kinetics and the results of this paper can be considered as the first confirmation of existence of the kinetic phenomena that are described by fractional derivatives with complex-power-law exponents. We want to stress here that with the help of a new complex fitting function for the complex permittivity it becomes possible to describe the whole process for real and imaginary parts simultaneously throughout the admissible frequency range (30 Hz-13 MHz). The fitting parameters obtained for the complex permittivity function for three temperatures (70, 90 and 110 °C) confirm in general the picture of reaction that was known qualitatively before. They also reveal some new features, which improve the interpretation of the whole polymerization process. We hope that these first results obtained in the paper will serve as a good stimulus for other researches to find the traces of the existence of new fractional kinetics in other relaxation processes unrelated to the dielectric relaxation. These results should lead to the reconsideration and generalization of irreversibility and kinetic phenomena that

  6. Modeling the Effect of Privatization on Behavior of Hurst Exponent Using Stochastic Catastrophe Theory

    Science.gov (United States)

    Bolgorian, Meysam; Raei, Reza

    In this paper using the global Hurst exponent, the impact of privatization of public companies in Iran on the degree of efficiency in Tehran Stock Exchange is assessed. The results show that selling public companies' share in Tehran Stock Exchange (TSE) leads to a structural break in degree of market development. To model this phenomenon a catastrophe approach is used and it is demonstrated that this structural break can be better explained by a cusp catastrophe model.

  7. Exponence, allomorphy and haplology in the number and State morphology of Modern Hebrew

    OpenAIRE

    Faust, Noam

    2018-01-01

    This paper provides an account of the regularities of plural exponence in Modern Hebrew. There are two genders in Modern Hebrew, each with its specific plural marker. Nouns can appear in the Construct or Free states, and the State of a noun also has an effect on the plural marking, though only in the case of masculine nouns. Finally, in nouns with possessive suffixes and in newly-formed dual nouns, plural number seems to be marked twice in the feminine noun, but only once in the masculine nou...

  8. Estimating the density-scaling exponent of a monatomic liquid from its pair potential

    DEFF Research Database (Denmark)

    Bøhling, Lasse; Bailey, Nicholas; Schrøder, Thomas

    2014-01-01

    This paper investigates two conjectures for calculating the density dependence of the density-scaling exponent γ of a single-component, pair-potential liquid with strong virial potential-energy correlations. The first conjecture gives an analytical expression for γ directly in terms of the pair...... potential. The second conjecture is a refined version of this involving the most likely nearest-neighbor distance determined from the pair-correlation function. The conjectures are tested by simulations of three systems, one of which is the standard Lennard-Jones liquid. While both expressions give...

  9. Gravitational collapse and naked singularities

    Indian Academy of Sciences (India)

    Suppose we have a one-parameter family of initial data sets ... the scaling law MBH ∝ |p − p∗|γ, where γ is a positive constant called a critical exponent. ... by more straightforward work [19], in which the causal structure of the critical solution ...

  10. Change in the family food environment is associated with positive dietary change in children

    Directory of Open Access Journals (Sweden)

    Hendrie Gilly

    2013-01-01

    saturated fat intake. Conclusions The present study was one of the first to quantify changes in the family food environment, and identify a number of factors which were associated with a positive dietary change. Because interventions focus on behaviour change, the findings may provide specific targets for intervention strategies in the future. Trial registration Australia New Zealand Clinical Trials Registry ACTRN12609000453280.

  11. Density-scaling exponents and virial potential-energy correlation coefficients for the (2n, n) Lennard-Jones system

    DEFF Research Database (Denmark)

    Friisberg, Ida Marie; Costigliola, Lorenzo; Dyre, Jeppe C.

    2017-01-01

    This paper investigates the relation between the density-scaling exponent γ and the virial potentialenergy coefficient R at several thermodynamic state points in three dimensions for the generalized (2n, n) Lennard-Jones (LJ) system for n = 4, 9, 12, 18, as well as for the standard n = 6 LJ syste...

  12. Analysis and control of chaotic behavior in boost converter by ramp compensation based on Lyapunov exponents assignment: theoretical and experimental investigation

    International Nuclear Information System (INIS)

    Zamani, Najmeh; Ataei, Mohammad; Niroomand, Mehdi

    2015-01-01

    Highlights: • Applying nonlinear analysis of complex dynamics displayed by current-mode controlled boost converter. • The ramp compensation method is used to control bifurcation and chaos in these converters based on bifurcation diagram and Lyapunov exponents assignment. • A discrete-time iterative nonlinear mapping model has been derived by inserting the ramp compensation parameter in the dynamical equations of the system. • A design methodology for chaos control is provided in this converter based on Lyapunov exponents assignment in desired values theoretically by proper selection of compensator slope. • Practical results are provided to confirm the theoretical analysis and simulations. - Abstract: Nonlinear analysis of complex dynamics displayed by current mode dc–dc converter and idea of Lyapunov exponents assignment by ramp compensator in order to control chaotic behavior is proposed in this article. A discrete-time iterative nonlinear mapping model is derived. The occurrence of the complex behaviors of bifurcation and chaos generated by varying the circuit parameters are investigated through numerical analysis and software implementation of the circuit. Next, in order to control bifurcation and chaos in these converters, the ramp compensation method is used. By inserting the ramp compensation parameter in the dynamical equations of the system, these complex behaviors are examined theoretically and numerically as well. It is proved that through this method, the stable period-one operation of the converter can be extended. By evaluating the Lyapunov exponents (LEs) of the system, the impact of the slope on the location of LEs are determined analytically. This leads to a design methodology for control of chaos in this converter based on LEs assignment in desired values by proper selection of compensator slope. By developing an experimental set up, practical results are obtained to confirm the theoretical analysis and simulations.

  13. Benford analysis of quantum critical phenomena: First digit provides high finite-size scaling exponent while first two and further are not much better

    Science.gov (United States)

    Bera, Anindita; Mishra, Utkarsh; Singha Roy, Sudipto; Biswas, Anindya; Sen(De), Aditi; Sen, Ujjwal

    2018-06-01

    Benford's law is an empirical edict stating that the lower digits appear more often than higher ones as the first few significant digits in statistics of natural phenomena and mathematical tables. A marked proportion of such analyses is restricted to the first significant digit. We employ violation of Benford's law, up to the first four significant digits, for investigating magnetization and correlation data of paradigmatic quantum many-body systems to detect cooperative phenomena, focusing on the finite-size scaling exponents thereof. We find that for the transverse field quantum XY model, behavior of the very first significant digit of an observable, at an arbitrary point of the parameter space, is enough to capture the quantum phase transition in the model with a relatively high scaling exponent. A higher number of significant digits do not provide an appreciable further advantage, in particular, in terms of an increase in scaling exponents. Since the first significant digit of a physical quantity is relatively simple to obtain in experiments, the results have potential implications for laboratory observations in noisy environments.

  14. Spectral analysis of structure functions and their scaling exponents in forced isotropic turbulence

    Science.gov (United States)

    Linkmann, Moritz; McComb, W. David; Yoffe, Samuel; Berera, Arjun

    2014-11-01

    The pseudospectral method, in conjunction with a new technique for obtaining scaling exponents ζn from the structure functions Sn (r) , is presented as an alternative to the extended self-similarity (ESS) method and the use of generalized structure functions. We propose plotting the ratio | Sn (r) /S3 (r) | against the separation r in accordance with a standard technique for analysing experimental data. This method differs from the ESS technique, which plots the generalized structure functions Gn (r) against G3 (r) , where G3 (r) ~ r . Using our method for the particular case of S2 (r) we obtain the new result that the exponent ζ2 decreases as the Taylor-Reynolds number increases, with ζ2 --> 0 . 679 +/- 0 . 013 as Rλ --> ∞ . This supports the idea of finite-viscosity corrections to the K41 prediction for S2, and is the opposite of the result obtained by ESS. The pseudospectral method permits the forcing to be taken into account exactly through the calculation of the energy input in real space from the work spectrum of the stirring forces. The combination of the viscous and the forcing corrections as calculated by the pseudospectral method is shown to account for the deviation of S3 from Kolmogorov's ``four-fifths''-law at all scales. This work has made use of the resources provided by the UK supercomputing service HECToR, made available through the Edinburgh Compute and Data Facility (ECDF). A. B. is supported by STFC, S. R. Y. and M. F. L. are funded by EPSRC.

  15. Families as Partners: Supporting Family Resiliency through Early Intervention

    Science.gov (United States)

    Frantz, Rebecca; Hansen, Sarah Grace; Squires, Jane; Machalicek, Wendy

    2018-01-01

    Child development occurs within the context of the child's family, neighborhood, and community environment. Early childhood providers support positive outcomes, not only for the children with whom they directly work with but also for their families. Families of children with developmental delays often experience unique challenges. A family…

  16. Some comments on Hurst exponent and the long memory processes on capital markets

    Science.gov (United States)

    Sánchez Granero, M. A.; Trinidad Segovia, J. E.; García Pérez, J.

    2008-09-01

    The analysis of long memory processes in capital markets has been one of the topics in finance, since the existence of the market memory could implicate the rejection of an efficient market hypothesis. The study of these processes in finance is realized through Hurst exponent and the most classical method applied is R/S analysis. In this paper we will discuss the efficiency of this methodology as well as some of its more important modifications to detect the long memory. We also propose the application of a classical geometrical method with short modifications and we compare both approaches.

  17. A remarkable new family of Jurassic insects (Neuroptera with primitive wing venation and its phylogenetic position in Neuropterida.

    Directory of Open Access Journals (Sweden)

    Qiang Yang

    Full Text Available BACKGROUND: Lacewings (insect order Neuroptera, known in the fossil record since the Early Permian, were most diverse in the Mesozoic. A dramatic variety of forms ranged in that time from large butterfly-like Kalligrammatidae to minute two-winged Dipteromantispidae. PRINCIPAL FINDINGS: We describe the intriguing new neuropteran family Parakseneuridae fam. nov. with three new genera and 15 new species from the Middle Jurassic of Daohugou (Inner Mongolia, China and the Early/Middle Jurassic of Sai-Sagul (Kyrgyzstan: Parakseneura undula gen. et sp. nov., P. albomacula gen. et sp. nov., P. curvivenis gen. et sp. nov., P. nigromacula gen. et sp. nov., P. nigrolinea gen. et sp. nov., P. albadelta gen. et sp. nov., P. cavomaculata gen. et sp. nov., P. inflata gen. et sp. nov., P. metallica gen. et sp. nov., P. emarginata gen. et sp. nov., P. directa gen. et sp. nov., Pseudorapisma jurassicum gen. et sp. nov., P. angustipenne gen. et sp. nov., P. maculatum gen. et sp. nov. (Daohugou; Shuraboneura ovata gen. et sp. nov. (Sai-Sagul. The family comprises large neuropterans with most primitive wing venation in the order indicated by the presence of ScA and AA1+2, and the dichotomous branching of MP, CuA, CuP, AA3+4, AP1+2. The phylogenetic position of Parakseneuridae was investigated using a phylogenetic analysis of morphological scoring for 33 families of extinct and extant Neuropterida combined with DNA sequence data for representatives of all extant families. Parakseneuridae were recovered in a clade with Osmylopsychopidae, Prohemerobiidae, and Ithonidae. CONCLUSIONS/SIGNIFICANCE: The presence of the presumed AA1+2 in wings of Parakseneuridae is a unique plesiomorphic condition hitherto unknown in Neuropterida, the clade comprising Neuroptera, Megaloptera, Raphidioptera. The relative uncertainty of phylogenetic position of Parakseneuridae and the majority of other families of Neuroptera reflects deficient paleontological data, especially from critical

  18. The Role of Ethnic Culture in Work-Family Balance among Armenian Women in Leadership Positions in Higher Education

    Science.gov (United States)

    Baran, Hasmig

    2012-01-01

    In contemporary society women leaders in education have struggled to balance work and family. While some women have succeeded in finding that balance, many others are still struggling. The purpose of this qualitative study was to examine the experiences of three Armenian women in senior-level leadership positions in higher education in the United…

  19. Professionals' positive perceptions of fathers are associated with more favourable attitudes towards including them in family interventions.

    Science.gov (United States)

    de Montigny, Francine; Gervais, Christine; Meunier, Sophie; Dubeau, Diane

    2017-12-01

    This Université du Québec en Outaouais study examined professionals' attitudes towards fathers, their perceived self-efficacy when working with them and their perceptions of the importance of including fathers in family interventions. Professionals in Québec, Canada, working in childcare fields such as education, social services, health, community services and management answered a self-report questionnaire between 2013 and 2015. The 296 respondents (90% females) had a mean age of 39 (20-65), were from urban, semi-urban and rural settings and provided services to families with children up to five years of age. Social service professionals perceived fathers more negatively than did other professionals. Even though male professionals perceived fathers more negatively, they felt more confident working with them than did their female counterparts. Positive perceptions of fathers were associated with more favourable attitudes towards including them in family interventions, and this association was mediated by the professionals' perceptions of their own self-efficacy. The most negative attitudes were reported by social service professionals. Male professionals viewed fathers more negatively but were more confident working with them than were female colleagues. Improving professionals' perceptions of fathers could help to promote their inclusion in family interventions. ©2017 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.

  20. Inferring wavelength dependence of AOD and Ångström exponent over a sub-tropical station in South Africa using AERONET data: Influence of meteorology, long-range transport and curvature effect

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, K. Raghavendra, E-mail: kanike.kumar@gmail.com [Discipline of Physics, School of Chemistry and Physics, Westville Campus, University of KwaZulu-Natal, Durban 4000 (South Africa); Sivakumar, V. [Discipline of Physics, School of Chemistry and Physics, Westville Campus, University of KwaZulu-Natal, Durban 4000 (South Africa); Reddy, R.R.; Gopal, K. Rama [Department of Physics, Aerosol and Atmospheric Research Laboratory, Sri Krishnadevaraya University, Anantapur 515 003, Andhra Pradesh (India); Adesina, A. Joseph [Discipline of Physics, School of Chemistry and Physics, Westville Campus, University of KwaZulu-Natal, Durban 4000 (South Africa)

    2013-09-01

    Aerosol optical properties over a southern sub-tropical site Skukuza, South Africa were studied to determine the variability of the aerosol characteristics using CIMEL Sunphotometer data as part of the AErosol RObotic NETwork (AERONET) from December 2005 to November 2006. Aerosol optical depth (AOD), Ångström exponent (α), and columnar water vapor (CWV) data were collected, analyzed, and compiled. Participating in this network provided a unique opportunity for understanding the sources of aerosols affecting the atmosphere of South Africa (SA) and the regional radiation budget. The meteorological patterns significantly (p < 0.05) influenced the amount and size distribution of the aerosols. Results showed that seasonal variation of AOD at 500 nm (AOD{sub 500}) over the observation site were characterized by low values (0.10–0.13) in autumn, moderate values (0.14–0.16) in summer and winter seasons, and high to very high values (0.18–0.40) during the spring, with an overall mean value of 0.18 ± 0.12. Ångström exponent α{sub 440–870}, varied from 0.5 to 2.89, with significant (p < 0.0001) seasonal variability. CWV showed a strong annual cycle with maximum values in the summer and autumn seasons. The relationship between AOD, Ångström exponent (α), and CWV showed a strong dependence (p < 0.0001) of α on AOD and CWV, while there was no significant correlation between AOD and CWV. Investigation of the adequacy of the simple use of the spectral AOD and Ångström exponent data was used in deriving the curvature (a{sub 2}) showed to obtain information for determining the aerosol-particle size. The negative a{sub 2} values are characterized by aerosol-size dominated by fine-mode (0.1–1 μm), while the positive curvatures indicate abundance of coarse particles (> 1 μm). Trajectory cluster analyses revealed that the air masses during the autumn and winter seasons have longer advection pathways, passing over the ocean and continent. This is reflected in the

  1. The high exponent limit $p \\to \\infty$ for the one-dimensional nonlinear wave equation

    OpenAIRE

    Tao, Terence

    2009-01-01

    We investigate the behaviour of solutions $\\phi = \\phi^{(p)}$ to the one-dimensional nonlinear wave equation $-\\phi_{tt} + \\phi_{xx} = -|\\phi|^{p-1} \\phi$ with initial data $\\phi(0,x) = \\phi_0(x)$, $\\phi_t(0,x) = \\phi_1(x)$, in the high exponent limit $p \\to \\infty$ (holding $\\phi_0, \\phi_1$ fixed). We show that if the initial data $\\phi_0, \\phi_1$ are smooth with $\\phi_0$ taking values in $(-1,1)$ and obey a mild non-degeneracy condition, then $\\phi$ converges locally uniformly to a piecewis...

  2. Children's Expressions of Positive Emotion Are Sustained by Smiling, Touching, and Playing with Parents and Siblings: A Naturalistic Observational Study of Family Life

    Science.gov (United States)

    Bai, Sunhye; Repetti, Rena L.; Sperling, Jacqueline B.

    2016-01-01

    Research on family socialization of positive emotion has primarily focused on the infant and toddler stages of development, and relied on observations of parent-child interactions in highly structured laboratory environments. Little is known about how children's spontaneous expressions of positive emotion are maintained in the uncontrolled…

  3. Position of the family Scrophulariaceae from Ukrainian flora in APG system

    OpenAIRE

    Hrytsyna M.

    2013-01-01

    In molecular phylogenetic system polyphyletic family Scrophulariaceae R.B.R is disintegrated into seven monophyletic groups: Scrophulariaceae, Veronicaceae, Orobanchaceae, Calceolariaceae, Stilbaceae, Phrymaceae and Linderniaceae within order Lamiales. They are composed mainly by the members of this family and also by small families of this order. Нoloparasitic and hemiparasitic genera re identified as a separate group. The genera of Ukrainian flora belonging to such tribes as Scrophulari...

  4. Cigarette Smoking among African American Youth from Single Mother Homes: Examining the Roles of Maternal Smoking and Positive Parenting within an Extended Family Framework

    Science.gov (United States)

    Foster, Sarah E.; Zalot, Alecia A.; Jones, Deborah J.

    2007-01-01

    The current study examined the main and interactive effects of three family context variables, maternal smoking, positive parenting behavior, and the quality of the mother's relationship with another adult or family member who assists with parenting (i.e., coparent), and adolescent smoking among African American youth from single mother homes. The…

  5. Attitude of the youth to the institute of family and family values

    Directory of Open Access Journals (Sweden)

    Artur A. Rean

    2016-03-01

    Full Text Available The paper draws attention to the large number of divorces in contemporary Russia. It is emphasized that much of them fall on the first years of marriage. However, most of the surveys conducted in recent years have shown that the family is one of the leading positions in the structure of adolescent value. On the basis of this juxtaposition, it is concluded that young people need to be specially trained for family life. Contemporary family and the school cannot cope with this task. We have carried out a large-scale empirical study in eight regions of different federal districts of Russia, the results of which are shown in the paper. Total sample amounted of more than 7,000 people. The sample included respondents from large and small cities in Russia, as well as from the villages of nuclear and one-parent families, families with 1-2 children and also large families. The research has shown that in the structure of life values the family still occupies the first position. It was also found that the vast majority of respondents emphasize the need to be specially trained for building a family. However, only one third of respondents believe that this can be done by conducting special courses on the family and family life in schools. For the majority of the respondents, their parent family is not a guide or a pattern. The greatest impact on the youth in the process of growing up is produced by mother. Fathers, occupying the second position, prove to be outsiders with a large gap. It was revealed that a generalized portrait of the mother and the father are completely positive, i.e. they do not contain any negative characteristics. The top ten most popular qualities to describe father and mother are the following: kind, reliable, caring, responsible, family-making, smart. Other qualities of the top ten highest priorities differ.

  6. Vigorous physical activity impairs myocardial function in patients with arrhythmogenic right ventricular cardiomyopathy and in mutation positive family members

    DEFF Research Database (Denmark)

    Saberniak, Jørg; Hasselberg, Nina E; Borgquist, Rasmus

    2014-01-01

    patients and 45 mutation-positive family members. Athletes were defined as subjects with ≥4 h vigorous exercise/week [≥1440 metabolic equivalents (METs × minutes/week)] during a minimum of 6 years. Athlete definition was fulfilled in 37/110 (34%) subjects. We assessed right ventricular (RV) and left...

  7. Position of the family Scrophulariaceae from Ukrainian flora in APG system

    Directory of Open Access Journals (Sweden)

    Myroslava R. Hrytsyna

    2013-04-01

    Full Text Available In molecular phylogenetic system polyphyletic family Scrophulariaceae R.B.R is disintegrated into seven monophyletic groups: Scrophulariaceae, Veronicaceae, Orobanchaceae, Calceolariaceae, Stilbaceae, Phrymaceae and Linderniaceae within order Lamiales. They are composed mainly by the members of this family and also by small families of this order. Нoloparasitic and hemiparasitic genera re identified as a separate group. The genera of Ukrainian flora belonging to such tribes as Scrophulariaceae, Veronicaceae, Orobanchaceae.

  8. Universal Scaling and Critical Exponents of the Anisotropic Quantum Rabi Model

    Science.gov (United States)

    Liu, Maoxin; Chesi, Stefano; Ying, Zu-Jian; Chen, Xiaosong; Luo, Hong-Gang; Lin, Hai-Qing

    2017-12-01

    We investigate the quantum phase transition of the anisotropic quantum Rabi model, in which the rotating and counterrotating terms are allowed to have different coupling strengths. The model interpolates between two known limits with distinct universal properties. Through a combination of analytic and numerical approaches, we extract the phase diagram, scaling functions, and critical exponents, which determine the universality class at finite anisotropy (identical to the isotropic limit). We also reveal other interesting features, including a superradiance-induced freezing of the effective mass and discontinuous scaling functions in the Jaynes-Cummings limit. Our findings are extended to the few-body quantum phase transitions with N >1 spins, where we expose the same effective parameters, scaling properties, and phase diagram. Thus, a stronger form of universality is established, valid from N =1 up to the thermodynamic limit.

  9. Detection of the onset of numerical chaotic instabilities by lyapunov exponents

    Directory of Open Access Journals (Sweden)

    Alicia Serfaty De Markus

    2001-01-01

    Full Text Available It is commonly found in the fixed-step numerical integration of nonlinear differential equations that the size of the integration step is opposite related to the numerical stability of the scheme and to the speed of computation. We present a procedure that establishes a criterion to select the largest possible step size before the onset of chaotic numerical instabilities, based upon the observation that computational chaos does not occur in a smooth, continuous way, but rather abruptly, as detected by examining the largest Lyapunov exponent as a function of the step size. For completeness, examination of the bifurcation diagrams with the step reveals the complexity imposed by the algorithmic discretization, showing the robustness of a scheme to numerical instabilities, illustrated here for explicit and implicit Euler schemes. An example of numerical suppression of chaos is also provided.

  10. Human Service Employees Coping with Job Stress, Family Stress and Work-Family Conflict.

    Science.gov (United States)

    Carbone, Dominic J.

    The intersection of work and family life has always been a popular topic of discussion among family theorists. This study examined human service employees in direct service positions coping with work stress, family stress, and work-family conflict. The effects of work stress, family stress and work-family conflict on depression were examined.…

  11. Feelings of Women With Strong Family Histories Who Subsequent to Their Breast Cancer Diagnosis Tested BRCA Positive.

    Science.gov (United States)

    Joseph, Meera; Rab, Faiza; Panabaker, Karen; Nisker, Jeff

    2015-05-01

    Family physicians in Canada as reported in several studies do not recognize the importance of family history in relation to breast/ovarian cancer and thus Canadian women with strong family histories continue to develop early-onset breast cancer without the knowledge of or ability to make choices regarding increased surveillance or preventative strategies. This study explored the feelings of women who learned about their hereditary risk only after their diagnosis younger than 52 years and who eventually tested positive for a BRCA gene mutation. Thirty-four such women were mailed an invitation to participate in this research including a letter of information, consent form, and discussion prompts for their written narrative response. Rigorous mixed method analyses were performed using Charmaz-based qualitative analyses as well as quantitative analyses. Thirteen women (38.2%) responded with narratives for qualitative analysis from which 4 themes were coconstructed as follows: I, types of emotions; II, emotional response; III, coping with emotions; and IV, advice to women at similar risk. Women felt they should have learned about their hereditary risk from their family physician and through public education before their diagnosis. Although not experienced at the time of diagnosis, anger, frustration, and regret were experienced after receiving their BRCA results. These emotions arose from our research participants' lack of opportunity for prior genetic counseling and testing opportunity for genetic counseling and testing. With increased public and physician education, it is hoped that women with significant family histories of breast/ovarian cancer will be identified before diagnosis and given options regarding cancer surveillance and risk reduction strategies.

  12. FUSION BASED MULTIMODAL AUTHENTICATION IN BIOMETRICS USING CONTEXT-SENSITIVE EXPONENT ASSOCIATIVE MEMORY MODEL : A NOVEL APPROACH

    OpenAIRE

    P. E. S. N. Krishna Prasad; Pavan Kumar K; M. V. Ramakrishna; B. D. C. N. Prasad

    2013-01-01

    Biometrics is one of the primary key concepts of real application domains such as aadhar card, passport, pan card, etc. In such applications user can provide two to three biometrics patterns like face, finger, palm, signature, iris data, and so on. We considered face and finger patterns for encoding and then also for verification. Using this data we proposed a novel model for authentication in multimodal biometrics often called Context-Sensitive Exponent Associative Memory Mode...

  13. Hartree-Fock study of the Anderson metal-insulator transition in the presence of Coulomb interaction: Two types of mobility edges and their multifractal scaling exponents

    Science.gov (United States)

    Lee, Hyun-Jung; Kim, Ki-Seok

    2018-04-01

    We investigate the role of Coulomb interaction in the multifractality of Anderson metal-insulator transition, where the Coulomb interaction is treated within the Hartree-Fock approximation, but disorder effects are taken into account exactly. An innovative technical aspect in our simulation is to utilize the Ewald-sum technique, which allows us to introduce the long-range nature of the Coulomb interaction into Hartree-Fock self-consistent equations of order parameters more accurately. This numerical simulation reproduces the Altshuler-Aronov correction in a metallic state and the Efros-Shklovskii pseudogap in an insulating phase, where the density of states ρ (ω ) is evaluated in three dimensions. Approaching the quantum critical point of a metal-insulator transition from either the metallic or insulting phase, we find that the density of states is given by ρ (ω ) ˜|ω| 1 /2 , which determines one critical exponent of the McMillan-Shklovskii scaling theory. Our main result is to evaluate the eigenfunction multifractal scaling exponent αq, given by the Legendre transformation of the fractal dimension τq, which characterizes the scaling behavior of the inverse participation ratio with respect to the system size L . Our multifractal analysis leads us to identify two kinds of mobility edges, one of which occurs near the Fermi energy and the other of which appears at a high energy, where the density of states at the Fermi energy shows the Coulomb-gap feature. We observe that the multifractal exponent at the high-energy mobility edge remains to be almost identical to that of the Anderson localization transition in the absence of Coulomb interactions. On the other hand, we find that the multifractal exponent near the Fermi energy is more enhanced than that at the high-energy mobility edge, suspected to result from interaction effects. However, both the multifractal exponents do not change even if the strength of the Coulomb interaction varies. We also show that the

  14. LGBTQ relationally based positive psychology: An inclusive and systemic framework.

    Science.gov (United States)

    Domínguez, Daniela G; Bobele, Monte; Coppock, Jacqueline; Peña, Ezequiel

    2015-05-01

    Positive psychologists have contributed to our understandings of how positive emotions and flexible cognition enhance resiliency. However, positive psychologists' research has been slow to address the relational resources and interactions that help nonheterosexual families overcome adversity. Addressing overlooked lesbian, gay, bisexual, transgender, or queer (LGBTQ) and systemic factors in positive psychology, this article draws on family resilience literature and LGBTQ literature to theorize a systemic positive psychology framework for working with nonheterosexual families. We developed the LGBTQ relationally based positive psychology framework that integrates positive psychology's strengths-based perspective with the systemic orientation of Walsh's (1996) family resilience framework along with the cultural considerations proposed by LGBTQ family literature. We theorize that the LGBTQ relationally based positive psychology framework takes into consideration the sociopolitical adversities impacting nonheterosexual families and sensitizes positive psychologists, including those working in organized care settings, to the systemic interactions of same-sex loving relationships. (c) 2015 APA, all rights reserved).

  15. Estimating the small-x exponent of the structure function g1NS from the Bjorken sum rule

    International Nuclear Information System (INIS)

    Knauf, Anke; Meyer-Hermann, Michael; Soff, Gerhard

    2002-01-01

    We present a new estimate of the exponent governing the small-x behavior of the nonsinglet structure function g 1 p-n derived under the assumption that the Bjorken sum rule is valid. We use the world wide average of α s and the NNNLO QCD corrections to the Bjorken sum rule. The structure function g 1 NS is found to be clearly divergent for small x

  16. Longitudinal Influence of Paternal Distress on Children’s Representations of Fathers, Family Cohesion, and Family Conflict

    Science.gov (United States)

    Adamsons, Kari L.; Robinson, JoAnn L.; Sabatelli, Ronald M.

    2014-01-01

    A parent’s distress is known to color children’s experiences of their families. Studies, however, have rarely focused on the levels of distress experienced by fathers, and in particular, as they affect the emotional experiences of their children. We examine the impact that fathers’ experience of distress throughout their children’s early years has on children’s emerging narrative representations of father-child relationships and of family conflict and cohesion. In this longitudinal investigation, fathers of young children reported their distress on two occasions in relation to self, the marital relationship, and the family climate. Fathers also concurrently reported on their children’s temperament, specifically negative emotionality. Children responded to story stem beginnings about challenging situations in the family and their narratives were scored for dysregulated negative-disciplinary and positive parental behaviors of fathers, family conflict themes, and family harmony themes. It was hypothesized that children of more distressed fathers would represent greater dysregulated fathering and higher levels of family conflict, and lower levels of positive fathering and family harmony than children of less distressed fathers. Further, the study examined whether this effect was mediated through the fathers’ reports of their children’s negative emotionality. Results partially supported the hypothesized direct and indirect effects. Children’s narratives of negative-disciplinary fathering and family conflict were more common in boys when fathers reported greater distress, and temperament ratings fully mediated this effect. However, their narratives of positive fathering and family harmony were not significantly affected. That positive family features were preserved in children’s narratives even in the face of greater father distress suggests that families may be able to build resilience to internalized distress through these positive narrative

  17. Profiled Roller Stress/Fatigue Life Analysis Methodology and Establishment of an Appropriate Stress/Life Exponent

    Science.gov (United States)

    1997-01-01

    The objective of this work was to determine the three dimensional volumetric stress field, surface pressure distribution and actual contact area between a 0.50" square roller with different crown profiles and a flat raceway surface using Finite Element Analysis. The 3-dimensional stress field data was used in conjunction with several bearing fatigue life theories to extract appropriate values for stress-life exponents. Also, results of the FEA runs were used to evaluate the laminated roller model presently used for stress and life prediction.

  18. Review Article: On the relation between the seismic activity and the Hurst exponent of the geomagnetic field at the time of the 2000 Izu swarm

    Directory of Open Access Journals (Sweden)

    F. Masci

    2013-09-01

    Full Text Available Many papers document the observation of earthquake-related precursory signatures in geomagnetic field data. However, the significance of these findings is ambiguous because the authors did not adequately take into account that these signals could have been generated by other sources, and the seismogenic origin of these signals have not been validated by comparison with independent datasets. Thus, they are not reliable examples of magnetic disturbances induced by the seismic activity. Hayakawa et al. (2004 claim that at the time of the 2000 Izu swarm the Hurst exponent of the Ultra-Low-Frequency (ULF: 0.001–10 Hz band of the geomagnetic field varied in accord with the energy released by the seismicity. The present paper demonstrates that the behaviour of the Hurst exponent was insufficiently investigated and also misinterpreted by the authors. We clearly show that during the Izu swarm the changes of the Hurst exponent were strongly related to the level of global geomagnetic activity and not to the increase of the local seismic activity.

  19. Work hours and work-family conflict: the double-edged sword of involvement in work and family.

    Science.gov (United States)

    Matthews, Russell A; Swody, Cathleen A; Barnes-Farrell, Janet L

    2012-08-01

    In this study, we examine the role of work hours in a model that incorporates involvement in both work and family with experiences of work-family conflict and subjective well-being. Self-report data were collected from 383 full-time employees and analysed using structural equation modelling techniques. Results demonstrate that role salience was positively related to behavioural involvement with work and with family. In turn, behavioural family involvement was negatively related to work hours and family-to-work conflict, while behavioural work involvement was positively related to work hours. Behavioural family involvement was also positively related to life satisfaction. Finally, both family-to-work conflict and end-of-workday strain were negatively related to life satisfaction. Our results provide insight into unexpected problems that might arise when employees place overly high importance on work and work long hours. This study serves as a foundation for researchers to examine the interplay of time spent with work and family with other aspects of the work-family interface. Copyright © 2011 John Wiley & Sons, Ltd.

  20. Fractality Evidence and Long-Range Dependence on Capital Markets: a Hurst Exponent Evaluation

    Science.gov (United States)

    Oprean, Camelia; Tănăsescu, Cristina

    2014-07-01

    Since the existence of market memory could implicate the rejection of the efficient market hypothesis, the aim of this paper is to find any evidence that selected emergent capital markets (eight European and BRIC markets, namely Hungary, Romania, Estonia, Czech Republic, Brazil, Russia, India and China) evince long-range dependence or the random walk hypothesis. In this paper, the Hurst exponent as calculated by R/S fractal analysis and Detrended Fluctuation Analysis is our measure of long-range dependence in the series. The results reinforce our previous findings and suggest that if stock returns present long-range dependence, the random walk hypothesis is not valid anymore and neither is the market efficiency hypothesis.

  1. Constructing the "Ideal" Family for Family-Centred Practice: Challenges for Delivery

    Science.gov (United States)

    Dodd, Jenny; Saggers, Sherry; Wildy, Helen

    2009-01-01

    Family-centred practice positions families as the key decision-makers, central to and experts in the wants and needs of their child. This paper discusses how families interviewed for a Western Australian study describe their relationships with a range of allied health professionals in the paediatric disability sector. The allied health…

  2. Rethinking Family Power.

    Science.gov (United States)

    Kranichfeld, Marion L.

    1987-01-01

    Men's power is emphasized in the family power literature on marital decision making. Little attention has been paid to women's power, accrued through their deeper embeddedness in intrafamilial roles. Micro-level analysis of family power demonstrates that women's positions in the family power structure rest not on the horizontal marital tie but…

  3. Orbital Exponent Optimization in Elementary VB Calculations of the Chemical Bond in the Ground State of Simple Molecular Systems

    Science.gov (United States)

    Magnasco, Valerio

    2008-01-01

    Orbital exponent optimization in the elementary ab-initio VB calculation of the ground states of H[subscript 2][superscript +], H[subscript 2], He[subscript 2][superscript +], He[subscript 2] gives a fair description of the exchange-overlap component of the interatomic interaction that is important in the bond region. Correct bond lengths and…

  4. Family income and young adolescents' perceived social position: Associations with self-esteem and life satisfaction in the UK Millennium Cohort Study

    NARCIS (Netherlands)

    R. Bannink (Rienke); A. Pearce (Anna); S. Hope (Steven)

    2016-01-01

    textabstractBackground Self-esteem and life satisfaction are important aspects of positive mental health in young people, and both are socially distributed. However, the majority of evidence is based on socioeconomic characteristics of the family. As children enter adolescence and gain independence,

  5. Shared vision promotes family firm performance.

    Science.gov (United States)

    Neff, John E

    2015-01-01

    A clear picture of the influential drivers of private family firm performance has proven to be an elusive target. The unique characteristics of private family owned firms necessitate a broader, non-financial approach to reveal firm performance drivers. This research study sought to specify and evaluate the themes that distinguish successful family firms from less successful family firms. In addition, this study explored the possibility that these themes collectively form an effective organizational culture that improves longer-term firm performance. At an organizational level of analysis, research findings identified four significant variables: Shared Vision (PNS), Role Clarity (RCL), Confidence in Management (CON), and Professional Networking (OLN) that positively impacted family firm financial performance. Shared Vision exhibited the strongest positive influence among the significant factors. In addition, Family Functionality (APGAR), the functional integrity of the family itself, exhibited a significant supporting role. Taken together, the variables collectively represent an effective family business culture (EFBC) that positively impacted the long-term financial sustainability of family owned firms. The index of effective family business culture also exhibited potential as a predictive non-financial model of family firm performance.

  6. Shared Vision promotes family firm performance

    Directory of Open Access Journals (Sweden)

    John Edward Neff

    2015-05-01

    Full Text Available A clear picture of the influential drivers of private family firm performance has proven to be an elusive target. The unique characteristics of private family owned firms necessitate a broader, non-financial approach to reveal firm performance drivers. This research study sought to specify and evaluate the themes that distinguish successful family firms from less successful family firms. In addition, this study explored the possibility that these themes collectively form an effective organizational culture that improves longer-term firm performance. At an organizational level of analysis, research findings identified four significant variables: Shared Vision (PNS, Role Clarity (RCL, Confidence in Management (CON, and Professional Networking (OLN that positively impacted family firm financial performance. Shared Vision exhibited the strongest positive influence among the significant factors. In addition, Family Functionality (APGAR, the functional integrity of the family itself exhibited a significant supporting role. Taken together, the variables collectively represent an effective family business culture (EFBC that positively impacted the long-term financial sustainability of family owned firms. The index of effective family business culture also exhibited potential as a predictive non-financial model of family firm performance.

  7. Estimate of the largest Lyapunov characteristic exponent of a high dimensional atmospheric global circulation model: a sensitivity analysis

    International Nuclear Information System (INIS)

    Guerrieri, A.

    2009-01-01

    In this report the largest Lyapunov characteristic exponent of a high dimensional atmospheric global circulation model of intermediate complexity has been estimated numerically. A sensitivity analysis has been carried out by varying the equator-to-pole temperature difference, the space resolution and the value of some parameters employed by the model. Chaotic and non-chaotic regimes of circulation have been found. [it

  8. The influence of young age and positive family history of breast cancer on the prognosis of ductal carcinoma in situ treated by excision with or without radiation therapy or by mastectomy

    International Nuclear Information System (INIS)

    Szelei-Stevens, Kathleen A.; Kuske, Robert R.; Yantsos, Valerie A.; Cederbom, Gunnar J.; Bolton, John S.; Fineberg, Barbara B.

    2000-01-01

    Background: Several recent studies have investigated the influence of family history on the progression of DCIS patients treated by tylectomy and radiation therapy. Since three treatment strategies have been used for DCIS at our institution, we evaluated the influence of family history and young age on outcome by treatment method. Methods: Between 1/1/82 and 12/31/92, 128 patients were treated for DCIS by mastectomy (n = 50, 39%), tylectomy alone (n = 43, 34%), and tylectomy with radiation therapy (n = 35, 27%). Median follow-up is 8.7 years. Thirty-nine patients had a positive family history of breast cancer; 26 in a mother, sister, or daughter (first-degree relative); and 26 in a grandmother, aunt, or cousin (second-degree relative). Thirteen patients had a positive family history in both first- and second-degree relatives. Results: Six women developed a recurrence in the treated breast; all of these were initially treated with tylectomy alone. There were no recurrences in the mastectomy group or the tylectomy patients treated with postoperative radiation therapy. Patients with a positive family history had a 10.3% local recurrence rate (LRR), vs. a 2.3% LRR in patients with a negative family history (p = 0.05). Four of 44 patients (9.1%) 50 years of age or younger recurred, compared to two of 84 patients (2.4%) over the age of 50 (p = 0.10). Fifteen patients had both a positive family history and were 50 years of age or younger. Among these women, the recurrence rate was 20%. Women in this group treated by lesionectomy alone had a LRR of 38% (3 of 8). Conclusion: The most important determinant of outcome was the selection of treatment modality, with all of the recurrences occurring in the tylectomy alone group. In addition to treatment method, a positive family history significantly influenced LRR in patients treated by tylectomy, especially in women 50 years of age or younger. These results suggest that DCIS patients, particularly premenopausal women with a

  9. Family dynamics and infant temperament in Danish families

    DEFF Research Database (Denmark)

    Wilson, M.E.; Hall, Elisabeth O.C.; White, M.A.

    1994-01-01

    temperament. A sample of 99 families in Odense, Denmark, completed the Family Dynamics Measure in the third trimester of pregnancy and again when the infant was 8-9 months old. At this second time, the mothers also completed the Revised Infant Temperament Questionnaire. Overall we found small changes......Transition to parenthood involves the fine balance of family dynamics which both affect, and are affected by, the infant's temperament. The purpose of this study was to investigate changes in family dynamics over the transition to parenthood and the relationship of family dynamics to infant......, although always in a negative direction, in family dynamics over this transition. The largest change was an increase in perceived role conflict reported by both mothers and fathers. Mothers reported more role conflict than fathers. Positive family dynamics were related to infant rhythmicity....

  10. Family dynamics and infant temperament in Danish families

    DEFF Research Database (Denmark)

    Wilson, M.E.; Hall, Elisabeth O.C.; White, M.A.

    1994-01-01

    , although always in a negative direction, in family dynamics over this transition. The largest change was an increase in perceived role conflict reported by both mothers and fathers. Mothers reported more role conflict than fathers. Positive family dynamics were related to infant rhythmicity.......Transition to parenthood involves the fine balance of family dynamics which both affect, and are affected by, the infant's temperament. The purpose of this study was to investigate changes in family dynamics over the transition to parenthood and the relationship of family dynamics to infant...... temperament. A sample of 99 families in Odense, Denmark, completed the Family Dynamics Measure in the third trimester of pregnancy and again when the infant was 8-9 months old. At this second time, the mothers also completed the Revised Infant Temperament Questionnaire. Overall we found small changes...

  11. A model of adaptation for families of elderly patients with dementia: focusing on family resilience.

    Science.gov (United States)

    Kim, Geun Myun; Lim, Ji Young; Kim, Eun Joo; Kim, Sang Suk

    2017-07-19

    We constructed a model explaining families' positive adaptation in chronic crisis situations such as the problematic behavior of elderly patients with dementia and attendant caregiving stress, based on the family resilience model. Our aim was to devise an adaptation model for families of elderly patients with dementia. A survey of problematic behavior in elderly patients with dementia, family stress, family resilience, and family adaptation was conducted with 292 consenting individuals. The collected data were analyzed using structural equation modeling. The communication process, family stress, and problematic behavior of elderly patients with dementia had direct and indirect effects on family adaptation, while belief system, organization pattern, and social support had indirect effects. Specifically, family stress and more severe problematic behavior by elderly patients with dementia negatively influenced family adaptation, while greater family resilience improved such adaptation. Interventions aiming to enhance family resilience, based on the results of this study, are required to help families with positive adaptation. Such family programs might involve practical support such as education on the characteristics of elderly persons with dementia and coping methods for their problematic behavior; forming self-help groups for families; revitalizing communication within families; and activating communication channels with experts.

  12. Pregnancy, parturition, parity and position in the family. Any influence on the development of paediatric inguinal hernia/hydrocele?

    Science.gov (United States)

    Irabor, D O; Ogundoyin O O; Ogunlana, D I

    2014-01-01

    To see if pre-partum factors have a relationship to the development of inguinal hernia in children. A prospective study on children with hernia. On first contact, the affected child was examined and data like the age, sex, weight, blood group, the diagnosis, side of the lesion and other co-morbid conditions was recorded. The mother filled a questionnaire about her age, parity, illness during pregnancy, her mode of delivery and the patient's position in the family. There were 104 patients from 103 mothers, their ages ranged from 13 days to 14 years with the highest incidence in the 1-4 age group. The sex ratio was overwhelmingly male (M:F ratio was 38:1). Right sided hernias were predominant. Only 7% had a family history. The peak age group of the mothers was 26-32 years and about 33% of the mothers had some illness during pregnancy. The birth positions of the patients showed that majority of them were either 1st or 2nd born children. Women of ages 26-32 likelyto have children with inguinal hernia. Malaria during pregnancy is unlikely to have a role to play. 1st and 2nd born male children have a higher chance of having inguinal hernia.

  13. Control of chaos in permanent magnet synchronous motor by using optimal Lyapunov exponents placement

    Energy Technology Data Exchange (ETDEWEB)

    Ataei, Mohammad, E-mail: ataei@eng.ui.ac.i [Department of Electrical Engineering, Faculty of Engineering, University of Isfahan, Hezar-Jerib St., Postal Code 8174673441, Isfahan (Iran, Islamic Republic of); Kiyoumarsi, Arash, E-mail: kiyoumarsi@eng.ui.ac.i [Department of Electrical Engineering, Faculty of Engineering, University of Isfahan, Hezar-Jerib St., Postal Code 8174673441, Isfahan (Iran, Islamic Republic of); Ghorbani, Behzad, E-mail: behzad.ghorbani63@gmail.co [Department of Control Engineering, Najafabad Azad University, Najafabad, Isfahan (Iran, Islamic Republic of)

    2010-09-13

    Permanent Magnet Synchronous Motor (PMSM) experiences chaotic behavior for a certain range of its parameters. In this case, since the performance of the PMSM degrades, the chaos should be eliminated. In this Letter, the control of the undesirable chaos in PMSM using Lyapunov exponents (LEs) placement is proposed that is also improved by choosing optimal locations of the LEs in the sense of predefined cost function. Moreover, in order to provide the physical realization of the method, nonlinear parameter estimator for the system is suggested. Finally, to show the effectiveness of the proposed methodology, the simulation results for applying this control strategy are provided.

  14. Percolation with first-and-second neighbour bonds: a renormalization-group calculation of critical exponents

    International Nuclear Information System (INIS)

    Riera, R.; Oliveira, P.M.C. de; Chaves, C.M.G.F.; Queiroz, S.L.A. de.

    1980-04-01

    A real-space renormalization group approach for the bond percolation problem in a square lattice with first- and second- neighbour bonds is proposed. The respective probabilities are treated, as independent variables. Two types of cells are constructed. In one of them the lattice is considered as two interpenetrating sublattices, first-neighbour bonds playing the role of intersublattice links. This allows the calculation of both critical exponents ν and γ, without resorting to any external field. Values found for the critical indices are in good agreement with data available in the literature. The phase diagram in parameter space is also obtained in each case. (Author) [pt

  15. Engagement in the electoral processes: scaling laws and the role of political positions.

    Science.gov (United States)

    Mantovani, M C; Ribeiro, H V; Lenzi, E K; Picoli, S; Mendes, R S

    2013-08-01

    We report on a statistical analysis of the engagement in the electoral processes of all Brazilian cities by considering the number of party memberships and the number of candidates for mayor and councillor. By investigating the relationships between the number of party members and the population of voters, we have found that the functional forms of these relationships are well described by sublinear power laws (allometric scaling) surrounded by a multiplicative log-normal noise. We have observed that this pattern is quite similar to those we previously reported for the relationships between the number of candidates (mayor and councillor) and population of voters [Europhys. Lett. 96, 48001 (2011)], suggesting that similar universal laws may be ruling the engagement in the electoral processes. We also note that the power-law exponents display a clear hierarchy, where the more influential is the political position the smaller is the value of the exponent. We have also investigated the probability distributions of the number of candidates (mayor and councillor), party memberships, and voters. The results indicate that the most influential positions are characterized by distributions with very short tails, while less influential positions display an intermediate power-law decay before showing an exponential-like cutoff. We discuss the possibility that, in addition to the political power of the position, limitations in the number of available seats can also be connected with this changing of behavior. We further believe that our empirical findings point out to an under-representation effect, where the larger the city is, the larger are the obstacles for more individuals to become directly engaged in the electoral process.

  16. The impact of leader-member exchange (LMX) on work-family interference and work-family facilitation

    NARCIS (Netherlands)

    L.G. Tummers (Lars); B.A.C. Bronkhorst (Babette)

    2014-01-01

    markdownabstract__Abstract__ Purpose – We analyze the effects of leadership on work-family spillovers. Specifically, we analyze the relationships between leadership (leader-member exchange, LMX) with one negative work-family spillover effect (work-family interference) and one positive work-family

  17. Positioning Analysis of Filipino Family Narratives in the Context of Prisoner Reintegration

    Directory of Open Access Journals (Sweden)

    Donald Jay Bertulfo

    2016-11-01

    Full Text Available Prisoner reintegration may be viewed as a crisis situation that may lead to a period of instability within the family. Existing researches in this area remain focused on the individual perspective of ex-offenders rather than the experiences of receiving families back in their households. In this study, we aim to examine the reintegration experiences of the family as a group from an initial state of chaos to equilibrium upon the reentry of an incarcerated parent. Using a sample of 12 interviews of family members left behind by incarcerated fathers, three major storylines relating to the family’s struggle for moral re-ascendancy in the context of parental reintegration are identified: othering, rehabilitation, and restoration. We explain the interlocking emotional, discursive, and material forms of labor embedded in the process of prisoner reintegration. Policy implications on social and institutional aid to the families of reintegrating fathers are also discussed.

  18. Complexified quantum field theory and 'mass without mass' from multidimensional fractional actionlike variational approach with dynamical fractional exponents

    International Nuclear Information System (INIS)

    El-Nabulsi, Ahmad Rami

    2009-01-01

    Multidimensional fractional actionlike variational problem with time-dependent dynamical fractional exponents is constructed. Fractional Euler-Lagrange equations are derived and discussed in some details. The results obtained are used to explore some novel aspects of fractional quantum field theory where many interesting consequences are revealed, in particular the complexification of quantum field theory, in particular Dirac operators and the novel notion of 'mass without mass'.

  19. Importance sampling with imperfect cloning for the computation of generalized Lyapunov exponents

    Science.gov (United States)

    Anteneodo, Celia; Camargo, Sabrina; Vallejos, Raúl O.

    2017-12-01

    We revisit the numerical calculation of generalized Lyapunov exponents, L (q ) , in deterministic dynamical systems. The standard method consists of adding noise to the dynamics in order to use importance sampling algorithms. Then L (q ) is obtained by taking the limit noise-amplitude → 0 after the calculation. We focus on a particular method that involves periodic cloning and pruning of a set of trajectories. However, instead of considering a noisy dynamics, we implement an imperfect (noisy) cloning. This alternative method is compared with the standard one and, when possible, with analytical results. As a workbench we use the asymmetric tent map, the standard map, and a system of coupled symplectic maps. The general conclusion of this study is that the imperfect-cloning method performs as well as the standard one, with the advantage of preserving the deterministic dynamics.

  20. Decrease in Hurst exponent of human gait with aging and neurodegenerative diseases

    International Nuclear Information System (INIS)

    Zhauang Jianjun; Ning Xinbao; Yang Xiaodong; Huo Chengyu; Hou Fengzhen

    2008-01-01

    In this paper the decrease in the Hurst exponent of human gait with aging and neurodegenerative diseases was observed by using an improved rescaled range (R/S) analysis method. It indicates that the long-range correlations of gait rhythm from young healthy people are stronger than those from the healthy elderly and the diseased. The result further implies that fractal dynamics in human gait will be altered due to weakening or impairment of neural control on locomotion resulting from aging and neurodegenerative diseases. Due to analysing short-term data sequences rather than long datasets required by most nonlinear methods, the algorithm has the characteristics of simplicity and sensitivity, most importantly, fast calculation as well as powerful anti-noise capacities. These findings have implications for modelling locomotor control and also for quantifying gait dynamics in varying physiologic and pathologic states

  1. Family Social Support Rate of HIV positive Individuals in Khorram Abad

    Directory of Open Access Journals (Sweden)

    mozhgan Massoudi

    2005-12-01

    Conclusion: Patients who receive more family social support, are more willing to say about their problem to other peoples, and use condom more frequently than other patients in their sexual activities. Since the majority of the studied patients received weak social support, it is recommended to improve and promote their social support by informing and educating their families.

  2. Socioeconomic status and parenting in ethnic minority families: testing a minority family stress model.

    Science.gov (United States)

    Emmen, Rosanneke A G; Malda, Maike; Mesman, Judi; van Ijzendoorn, Marinus H; Prevoo, Mariëlle J L; Yeniad, Nihal

    2013-12-01

    According to the family stress model (Conger & Donnellan, 2007), low socioeconomic status (SES) predicts less-than-optimal parenting through family stress. Minority families generally come from lower SES backgrounds than majority families, and may experience additional stressors associated with their minority status, such as acculturation stress. The primary goal of this study was to test a minority family stress model with a general family stress pathway, as well as a pathway specific to ethnic minority families. The sample consisted of 107 Turkish-Dutch mothers and their 5- to 6-year-old children, and positive parenting was observed during a 7-min problem-solving task. In addition, mothers reported their daily hassles, psychological distress, and acculturation stress. The relation between SES and positive parenting was partially mediated by both general maternal psychological stress and maternal acculturation stress. Our study contributes to the argument that stressors specific to minority status should be considered in addition to more general demographic and family stressors in understanding parenting behavior in ethnic minority families.

  3. Effectiveness evaluation of the Positive Family Support intervention: A three-tiered public health delivery model for middle schools.

    Science.gov (United States)

    Smolkowski, Keith; Seeley, John R; Gau, Jeffery M; Dishion, Tom J; Stormshak, Elizabeth A; Moore, Kevin J; Falkenstein, Corrina A; Fosco, Gregory M; Garbacz, S Andrew

    2017-06-01

    This article presents the results of an evaluation of Positive Family Support, an ecological family intervention and treatment approach to parent supports and family management training developed from a history of basic and translational research. This effectiveness trial, with 41 public middle schools randomly assigned to intervention or control, examined student-, teacher-, and parent-reported outcomes, as well as math and reading scores and school attendance. Multilevel analyses suggested that for students at risk for behavior problems, immediate-intervention schools outperformed control schools on parent-reported negative school contacts for students at risk for behavior problems. Implementation, however, was hampered by several challenges, including school funding cuts, lack of staff time to provide parenting supports, and staff turnover. Given that preventive interventions are generally cost effective, it is critical that researchers continue their efforts to refine these interventions and find ways to support schools' implementation of evidence-based programs that can reduce problem behavior. This article is part of a special issue "Parental Engagement in School-Based Interventions". Copyright © 2017 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.

  4. Proneness to social anxiety modulates neural complexity in the absence of exposure: A resting state fMRI study using Hurst exponent.

    Science.gov (United States)

    Gentili, Claudio; Vanello, Nicola; Cristea, Ioana; David, Daniel; Ricciardi, Emiliano; Pietrini, Pietro

    2015-05-30

    To test the hypothesis that brain activity is modulated by trait social anxiety, we measured the Hurst Exponent (HE), an index of complexity in time series, in healthy individuals at rest in the absence of any social trigger. Functional magnetic resonance imaging (fMRI) time series were recorded in 36 subjects at rest. All volunteers were healthy without any psychiatric, medical or neurological disorder. Subjects completed the Liebowitz Social Anxiety Scale (LSAS) and the Brief Fear of Negative Evaluation (BFNE) to assess social anxiety and thoughts in social contexts. We also obtained the fractional Amplitude of Low Frequency Fluctuations (fALFF) of the BOLD signal as an independent control measure for HE data. BFNE scores correlated positively with HE in the posterior cingulate/precuneus, while LSAS scores correlated positively with HE in the precuneus, in the inferior parietal sulci and in the parahippocamus. Results from fALFF were highly consistent with those obtained using LSAS and BFNE to predict HE. Overall our data indicate that spontaneous brain activity is influenced by the degree of social anxiety, on a continuum and in the absence of social stimuli. These findings suggest that social anxiety is a trait characteristic that shapes brain activity and predisposes to different reactions in social contexts. Copyright © 2015. Published by Elsevier Ireland Ltd.

  5. Positive selection in the SLC11A1 gene in the family Equidae.

    Science.gov (United States)

    Bayerova, Zuzana; Janova, Eva; Matiasovic, Jan; Orlando, Ludovic; Horin, Petr

    2016-05-01

    Immunity-related genes are a suitable model for studying effects of selection at the genomic level. Some of them are highly conserved due to functional constraints and purifying selection, while others are variable and change quickly to cope with the variation of pathogens. The SLC11A1 gene encodes a transporter protein mediating antimicrobial activity of macrophages. Little is known about the patterns of selection shaping this gene during evolution. Although it is a typical evolutionarily conserved gene, functionally important polymorphisms associated with various diseases were identified in humans and other species. We analyzed the genomic organization, genetic variation, and evolution of the SLC11A1 gene in the family Equidae to identify patterns of selection within this important gene. Nucleotide SLC11A1 sequences were shown to be highly conserved in ten equid species, with more than 97 % sequence identity across the family. Single nucleotide polymorphisms (SNPs) were found in the coding and noncoding regions of the gene. Seven codon sites were identified to be under strong purifying selection. Codons located in three regions, including the glycosylated extracellular loop, were shown to be under diversifying selection. A 3-bp indel resulting in a deletion of the amino acid 321 in the predicted protein was observed in all horses, while it has been maintained in all other equid species. This codon comprised in an N-glycosylation site was found to be under positive selection. Interspecific variation in the presence of predicted N-glycosylation sites was observed.

  6. Positioning Analysis of Filipino Family Narratives in the Context of Prisoner Reintegration

    OpenAIRE

    Donald Jay Bertulfo; Nico Canoy; Michael Angelo Celeste

    2016-01-01

    Prisoner reintegration may be viewed as a crisis situation that may lead to a period of instability within the family. Existing researches in this area remain focused on the individual perspective of ex-offenders rather than the experiences of receiving families back in their households. In this study, we aim to examine the reintegration experiences of the family as a group from an initial state of chaos to equilibrium upon the reentry of an incarcerated parent. Using a sample of 12 interview...

  7. Dual-career family as an exampleof egalitarian family

    Directory of Open Access Journals (Sweden)

    Joanna Ostrouch-Kamińska

    2011-11-01

    Full Text Available The economic, cultural, and social transformation, growth of women's economic strength as well as the level of their education, and development of ideas of equal rights of women and men on the labour market and in social life cause changes in gender relation in the family. Poles more and more often declare and support egalitarian family, and a new model of a family appears among existing ones – dual-career family.The main aim of the article is to consider the sources of its rise, description of gender positions in marital relation, the division of tasks and responsibilities, possible dilemmas and conflicts, but also emotional, intellectual and social advantages. The analysis were put into context of changes in defining and describing family, and also in context of different family discourses. One of them was underlined the most – egalitarian one as the most approximate to the way of defining and understanding dual-career family model.

  8. [A PhD completed 7. Just add positivity? Dental caries, obesity and problem behaviour in children: the role of parents and family -relations].

    Science.gov (United States)

    de Jong-Lenters, M

    2016-11-01

    In this doctoral research project the relationship between, on the one hand, parenting and the functioning of families, and, on the other, child dental health were measured on the basis of interviews, questionnaires and observations of parent-child interaction. The groups studied consisted of children with and without caries and a variety of socio-economic backgrounds. The analyses revealed a distinct and significant difference between children with and children without caries with respect to parenting style and parent-child interaction. Positive parenting skills, such as positive involvement, positive reinforcement and problem-solving ability, correlate less often with children with caries. The study also revealed that children of parents with a parenting style that involved coercion and strict type of discipline, combined with the expression of little warmth, had a greater likelihood of developing caries. No relationship was found between an unhealthy high Body Mass Index (BMI) and the presence of dental caries. There was a significant relationship between behavioural problems and the presence of dental caries, which may be explained by an underlying influence of the family factors that were measured.

  9. The impact of leader-member exchange (LMX) on work-family interference and work-family facilitation

    OpenAIRE

    Tummers, Lars; Bronkhorst, Babette

    2014-01-01

    markdownabstract__Abstract__ Purpose – We analyze the effects of leadership on work-family spillovers. Specifically, we analyze the relationships between leadership (leader-member exchange, LMX) with one negative work-family spillover effect (work-family interference) and one positive work-family spillover effect (work-family facilitation). We hypothesize that LMX influences work-family spillover via different mediators, rather than one all-encompassing mediator, such as empowerment. Design/m...

  10. Retrievals of aerosol optical depth and Angström exponent from ground-based Sun-photometer data of Singapore.

    Science.gov (United States)

    Salinas, Santo V; Chew, Boon N; Liew, Soo C

    2009-03-10

    The role of aerosols in climate and climate change is one of the factors that is least understood at the present. Aerosols' direct interaction with solar radiation is a well understood mechanism that affects Earth's net radiative forcing. However, quantifying its magnitude is more problematic because of the temporal and spatial variability of aerosol particles. To enhance our understanding of the radiative effects of aerosols on the global climate, Singapore has joined the AERONET (Aerosol Robotic Network) worldwide network by contributing ground-based direct Sun measurements performed by means of a multiwavelength Sun-photometer instrument. Data are collected on an hourly basis, then are uploaded to be fully screened and quality assured by AERONET. We use a one year data record (level 1.5/2.0) of measured columnar atmospheric optical depth, spanning from November 2006 to October 2007, to study the monthly and seasonal variability of the aerosol optical depth and the Angström exponent. We performed independent retrievals of these parameters (aerosol optical depth and Angström exponent) by using the photometer's six available bands covering the near-UV to near-IR (380-1080 nm). As a validation, our independent retrievals were compared with AERONET 1.5/2.0 level direct Sun product.

  11. Assessment of Effects of a Delay Block and a Nonlinear Block in Systems with Chaotic Behavior Using Lyapunov Exponents

    Directory of Open Access Journals (Sweden)

    Pablo César Rodríguez Gómez

    2017-05-01

    Full Text Available Context: Because feedback systems are very common and widely used, studies of the structural characteristics under which chaotic behavior is generated have been developed. These can be separated into a nonlinear system and a linear system at least of the third order. Methods such as the descriptive function have been used for analysis. Method: A feedback system is proposed comprising a linear system, a nonlinear system and a delay block, in order to assess his behavior using Lyapunov exponents. It is evaluated with three different linear systems, different delay values and different values for parameters of nonlinear characteristic, aiming to reach chaotic behavior. Results: One hundred experiments were carried out for each of the three linear systems, by changing the value of some parameters, assessing their influence on the dynamics of the system. Contour plots that relate these parameters to the Largest Lyapunov exponent were obtained and analyzed. Conclusions: In spite non-linearity is a condition for the existence of chaos, this does not imply that any nonlinear characteristic generates a chaotic system, it is reflected by the contour plots showing the transitions between chaotic and no chaotic behavior of the feedback system. Language: English

  12. The impact of leader-member exchange (LMX) on work-family interference and work-family facilitation

    NARCIS (Netherlands)

    L.G. Tummers (Lars); B.A.C. Bronkhorst (Babette)

    2014-01-01

    markdownabstract__Abstract__ __Purpose__ – We analyze the effects of leadership on work-family spillovers. Specifically, we analyze the relationships between leadership (leader-member exchange, LMX) with one negative work-family spillover effect (work-family interference) and one positive

  13. When Family-Supportive Supervision Matters: Relations between Multiple Sources of Support and Work-Family Balance

    Science.gov (United States)

    Greenhaus, Jeffrey H.; Ziegert, Jonathan C.; Allen, Tammy D.

    2012-01-01

    This study examines the mechanisms by which family-supportive supervision is related to employee work-family balance. Based on a sample of 170 business professionals, we found that the positive relation between family-supportive supervision and balance was fully mediated by work interference with family (WIF) and partially mediated by family…

  14. The effects of parental education and family income on mother-child relationships, father-child relationships, and family environments in the People's Republic of China.

    Science.gov (United States)

    Zhang, Xiao

    2012-12-01

    Using a cross-sectional design with 407 Chinese children aged 3-5 years and their parents, this study examined the effects of socioeconomic status, specifically parents' education and family income, on the children's mother-child relationships, father-child relationships, and the social environment in their families. The results indicated that income negatively predicted conflict in father-child relationships and positively predicted family active-recreational environments. Income also positively predicted family cohesion among girls but not boys. Maternal education negatively predicted conflict in mother-child relationships and positively predicted closeness in mother-child and father-child relationships, family cohesion, and the intellectual-cultural and active-recreational environments in the family. Paternal education positively predicted family cohesion and intellectual-cultural and active-recreational environments. Income was found to partially mediate the effects of both maternal and paternal education on family active-recreational environments. Findings are discussed in the frameworks of the family stress model and the family investment model. © FPI, Inc.

  15. Risk and Resilience in Military Children and Families

    Science.gov (United States)

    2011-11-01

    score not assoc with child or family functioning • Spouses positive parenting and SM’s positive family problem solving assoc with child prosocial ...CI Seven Core Components Family focused care management (e.g. ensuring instrumental support/attention to complications) Emotion regulation skill

  16. The Family Liaison Position in High-Poverty, Urban Schools

    Science.gov (United States)

    Dretzke, Beverly J.; Rickers, Susan R.

    2016-01-01

    This study examined the roles and responsibilities of family liaisons working in urban schools with enrollments characterized by high poverty, high mobility, and ethnic diversity. Results indicated that the major responsibilities of the liaisons were creating a trusting and welcoming environment, facilitating parent involvement in the school,…

  17. Next-generation leadership development in family businesses: the critical roles of shared vision and family climate.

    Science.gov (United States)

    Miller, Stephen P

    2014-01-01

    The multigenerational survival rate for family-owned businesses is not good. Lack of a shared vision for the family enterprise and weak next-generation leadership are often cited as two of the leading reasons for the failure of family firms to successfully transition from one generation of family ownership to the next. The climate of the business-owning family has also been suggested as important to the performance of the family enterprise. Despite these commonly held tenets, there is a lack of rigorous quantitative research that explores the relationships among these three factors. To address this gap, a quantitative study of 100 next-generation family firm leaders and 350 family and non-family leaders and employees with whom they work was conducted. The results demonstrate that a shared vision for the family business has a strong effect on the leadership effectiveness of next-generation family leaders and a moderate effect on the degree to which they are positively engaged with their work. The findings also show that two dimensions of family climate significantly influence the likelihood that a shared vision for the family firm has been created. Open communication in the family is positively related to the presence of a shared vision for the business. Intergenerational authority, which refers to a senior generation that exercises unquestioned authority and sets the rules, is negatively related to the presence of a shared vision. Surprisingly, a third dimension of family climate, cognitive cohesion, which includes shared values in the family, had no relationship with the degree to which there was a shared vision for the family business. The implications for family business owners is that they would be wise to spend as much time on fostering a positive family climate characterized by open communication as they do on creating and executing a successful business strategy if their goal is to pass the business from one generation of family owners to the next.

  18. Next-generation leadership development in family businesses: the critical roles of shared vision and family climate

    Science.gov (United States)

    Miller, Stephen P.

    2014-01-01

    The multigenerational survival rate for family-owned businesses is not good. Lack of a shared vision for the family enterprise and weak next-generation leadership are often cited as two of the leading reasons for the failure of family firms to successfully transition from one generation of family ownership to the next. The climate of the business-owning family has also been suggested as important to the performance of the family enterprise. Despite these commonly held tenets, there is a lack of rigorous quantitative research that explores the relationships among these three factors. To address this gap, a quantitative study of 100 next-generation family firm leaders and 350 family and non-family leaders and employees with whom they work was conducted. The results demonstrate that a shared vision for the family business has a strong effect on the leadership effectiveness of next-generation family leaders and a moderate effect on the degree to which they are positively engaged with their work. The findings also show that two dimensions of family climate significantly influence the likelihood that a shared vision for the family firm has been created. Open communication in the family is positively related to the presence of a shared vision for the business. Intergenerational authority, which refers to a senior generation that exercises unquestioned authority and sets the rules, is negatively related to the presence of a shared vision. Surprisingly, a third dimension of family climate, cognitive cohesion, which includes shared values in the family, had no relationship with the degree to which there was a shared vision for the family business. The implications for family business owners is that they would be wise to spend as much time on fostering a positive family climate characterized by open communication as they do on creating and executing a successful business strategy if their goal is to pass the business from one generation of family owners to the next. PMID

  19. Next-Generation Leadership Development in Family Businesses: The Critical Roles of Shared Vision and Family Climate

    Directory of Open Access Journals (Sweden)

    Stephen Phillip Miller

    2014-12-01

    Full Text Available The multigenerational survival rate for family-owned businesses is not good. Lack of a shared vision for the family enterprise and weak next-generation leadership are often cited as two of the leading reasons for the failure of family firms to successfully transition from one generation of family ownership to the next. The climate of the business-owning family has also been suggested as important to the performance of the family enterprise. Despite these commonly held tenets, there is a lack of rigorous quantitative research that explores the relationships among these three factors. To address this gap, a quantitative study of 100 next-generation family firm leaders and 350 family and non-family leaders and employees with whom they work was conducted. The results demonstrate that a shared vision for the family business has a strong effect on the leadership effectiveness of next-generation family leaders and a moderate effect on the degree to which they are positively engaged with their work. The findings also show that two dimensions of family climate significantly influence the likelihood that a shared vision for the family firm has been created. Open communication in the family is positively related to the presence of a shared vision for the business. Intergenerational authority, which refers to a senior generation that exercises unquestioned authority and sets the rules, is negatively related to the presence of a shared vision. Surprisingly, a third dimension of family climate, cognitive cohesion, which includes shared values in the family, had no relationship with the degree to which there was a shared vision for the family business. The implications for family business owners is that they would be wise to spend as much time on fostering a positive family climate characterized by open communication as they do on creating and executing a successful business strategy if their goal is to pass the business from one generation of family owners to

  20. Efektivita kapitálových trhů: Fraktální dimenze, Hurstův exponent a entropie

    Czech Academy of Sciences Publication Activity Database

    Krištoufek, Ladislav; Vošvrda, Miloslav

    2012-01-01

    Roč. 60, č. 2 (2012), s. 208-221 ISSN 0032-3233 R&D Projects: GA ČR GA402/09/0965 Institutional support: RVO:67985556 Keywords : capital markets efficiency * fractal dimension * long-range dependence * entropy Subject RIV: AH - Economics Impact factor: 0.722, year: 2012 http://library.utia.cas.cz/separaty/2012/E/kristoufek-capital markets efficiency fractal dimension hurst exponent and entropy.pdf

  1. Reliability of Lyapunov characteristic exponents computed by the two-particle method

    Science.gov (United States)

    Mei, Lijie; Huang, Li

    2018-03-01

    For highly complex problems, such as the post-Newtonian formulation of compact binaries, the two-particle method may be a better, or even the only, choice to compute the Lyapunov characteristic exponent (LCE). This method avoids the complex calculations of variational equations compared with the variational method. However, the two-particle method sometimes provides spurious estimates to LCEs. In this paper, we first analyze the equivalence in the definition of LCE between the variational and two-particle methods for Hamiltonian systems. Then, we develop a criterion to determine the reliability of LCEs computed by the two-particle method by considering the magnitude of the initial tangent (or separation) vector ξ0 (or δ0), renormalization time interval τ, machine precision ε, and global truncation error ɛT. The reliable Lyapunov characteristic indicators estimated by the two-particle method form a V-shaped region, which is restricted by d0, ε, and ɛT. Finally, the numerical experiments with the Hénon-Heiles system, the spinning compact binaries, and the post-Newtonian circular restricted three-body problem strongly support the theoretical results.

  2. Work-family conflict and enrichment in nurses: between job demands, perceived organisational support and work-family backlash.

    Science.gov (United States)

    Ghislieri, Chiara; Gatti, Paola; Molino, Monica; Cortese, Claudio G

    2017-01-01

    This study investigated how work relationships (perceived organisational support, supervisor and co-worker work-family backlash) and job demands (workload, emotional dissonance) can interact with work-family conflict and work-family enrichment. Despite the extensive literature on the work-family interface, few studies on the nursing profession have considered the role of job demands and work relationships, focusing on both the positive and negative side of the work-family interface. The study involved a sample of 500 nurses working in an Italian hospital. Hierarchical multiple regression analyses were used to test hypotheses. Analyses showed that work-family conflict has a positive relationship with job demands and supervisor backlash, and a negative relationship with perceived organisational support. Work-family enrichment was found to have a negative relationship with job demands and a positive relationship with perceived organisational support. No significant relationships were found between work-family enrichment and both backlash dimensions. The study confirmed the importance of promoting a balance between job demands and resources in order to create favourable conditions for work-family enrichment and to prevent work-family conflict. The findings suggest that it may be advisable for health-care organisations to invest in measures at individual, team and organisational levels, specifically in training and counselling for nurses and supervisors. © 2016 John Wiley & Sons Ltd.

  3. Family co-operation programme description.

    Science.gov (United States)

    Peine, H A; Terry, T

    1990-01-01

    Current parenting practices indicate a continuing trend towards less family interaction. Institutional attempts to intervene with parents often fail. The 'Family Co-operation Programme' provides a tangible method for families and schools to work together in preventing alcohol and drug abuse, by utilising the positive influence of the home and strengthening family relationships. The Board of Education for the State of Utah has tested and is currently implementing a unique, low-cost, alternative to impact on the home. Utilising a K-12 alcohol/drug abuse school-based curriculum, the child, based on his/her inclass training, becomes the resource for family co-operation activities. These include training in coping skills, decision-making, resistance to peer persuasion, increased self-esteem and alcohol/drug information. Grade level materials go home with the child, who returns a requested parent evaluation. Data for over one thousand families show the positive impact of the activities.

  4. Family involvement and hotel online reputation

    Directory of Open Access Journals (Sweden)

    J. Diéguez-Soto

    2017-07-01

    Full Text Available Online reputation is nowadays particularly significant in the context of hotel firms due to the high sensitivity and enormous influence of electronic word-of-mouth activities of customers. Since there is still no clear set of online reputation-generating factors, the aim of this paper is to contribute to this knowledge considering the role of family governance as an antecedent of hotel online reputation. Specifically, our purpose is to explain whether the heterogeneity among family firms regarding their family influence on the business exerts a significant effect on online reputation of hotel firms, investigating how family ownership and family management dimensions interact in terms of influencing online reputation. Our findings, based on a sample of 157 Spanish family hotels, indicate a positive influence of family ownership on a hotel's online reputation, augmented by a positive moderating effect of the family management represented by the presence of a family CEO managing the hotel.

  5. Adult family relationships in the context of friendship

    Science.gov (United States)

    Fuller-Iglesias, Heather R.; Webster, Noah; Antonucci, Toni C.

    2013-01-01

    The present study examined the complex way in which relationships with family and friends shape health and well-being in adulthood over time. Specifically, we explored whether the longitudinal effects of positive and negative family relationship quality on health and well-being differ in the context of varying levels of positive friend relationships. Data were from two waves (1992/1993 and 2005) of the Social Relations, Aging and Health Study. The sample included respondents aged 18 and older at Wave 1 who reported having a best friend at both waves (N = 455), and consisted of 291 (64%) women and 164 (36%) men. Wave 1 friend positivity and family positivity interacted to predict self-rated health but not self-esteem, indicating that among respondents with a less positive friend relationship, more positive family relationships were related to worse health at Wave 2. Wave 1 friend positivity and family negativity significantly interacted to predict self-rated health and self-esteem at Wave 2. The nature of the interactions were consistent in that among respondents with a more highly positive friend relationship, less negative family relationships were linked to better health and self-esteem at Wave 2. Findings provide insight into the complex way in which social relations impact positive outcomes in adulthood. Previous studies have documented the consistent and straightforward manner in which negative relationships impact health and well-being, whereas this study illustrates that the role of positive social relations is more variable and dependent on multiple relationship contexts. PMID:24273462

  6. Working mothers: Family-work conflict, job performance and family/work variables

    Directory of Open Access Journals (Sweden)

    Cynthia J Patel

    2006-10-01

    Full Text Available The present study examined the relationship between family-work conflict, job performance and selected work and family characteristics in a sample of working mothers employed at a large retail organization. The hypothesis of a negative relationship between family-work conflict and job performance was rejected. Married women reported significantly higher family-work conflict than unmarried women, while women in the highest work category gained the highest job performance rating. More than half the sample indicated that paid work was more important than their housework and reported that their working had a positive impact on their families. The findings are discussed in relation to the changing work and family identities of non-career women.

  7. Understanding familial and non-familial renal cell cancer.

    Science.gov (United States)

    Bodmer, Daniëlle; van den Hurk, Wilhelmina; van Groningen, Jan J M; Eleveld, Marc J; Martens, Gerard J M; Weterman, Marian A J; van Kessel, Ad Geurts

    2002-10-01

    Molecular genetic analysis of familial and non-familial cases of conventional renal cell carcinoma (RCC) revealed a critical role(s) for multiple genes on human chromosome 3. For some of these genes, e.g. VHL, such a role has been firmly established, whereas for others, definite confirmation is still pending. Additionally, a novel role for constitutional chromosome 3 translocations as risk factors for conventional RCC development is rapidly emerging. Also, several candidate loci have been mapped to other chromosomes in both familial and non-familial RCCs of distinct histologic subtypes. The MET gene on chromosome 7, for example, was found to be involved in both forms of papillary RCC. A PRCC-TFE3 fusion gene is typically encountered in t(X;1)-positive non-familial papillary RCCs and results in abrogation of the cell cycle mitotic spindle checkpoint in a dominant-negative fashion, thus leading to RCC. Together, these data turn human RCC into a model system in which different aspects of both familial and non-familial syndromes may act as novel paradigms for cancer development.

  8. On the improvement of Wiener attack on RSA with small private exponent.

    Science.gov (United States)

    Wu, Mu-En; Chen, Chien-Ming; Lin, Yue-Hsun; Sun, Hung-Min

    2014-01-01

    RSA system is based on the hardness of the integer factorization problem (IFP). Given an RSA modulus N = pq, it is difficult to determine the prime factors p and q efficiently. One of the most famous short exponent attacks on RSA is the Wiener attack. In 1997, Verheul and van Tilborg use an exhaustive search to extend the boundary of the Wiener attack. Their result shows that the cost of exhaustive search is 2r + 8 bits when extending the Weiner's boundary r bits. In this paper, we first reduce the cost of exhaustive search from 2r + 8 bits to 2r + 2 bits. Then, we propose a method named EPF. With EPF, the cost of exhaustive search is further reduced to 2r - 6 bits when we extend Weiner's boundary r bits. It means that our result is 2(14) times faster than Verheul and van Tilborg's result. Besides, the security boundary is extended 7 bits.

  9. On the Improvement of Wiener Attack on RSA with Small Private Exponent

    Directory of Open Access Journals (Sweden)

    Mu-En Wu

    2014-01-01

    Full Text Available RSA system is based on the hardness of the integer factorization problem (IFP. Given an RSA modulus N=pq, it is difficult to determine the prime factors p and q efficiently. One of the most famous short exponent attacks on RSA is the Wiener attack. In 1997, Verheul and van Tilborg use an exhaustive search to extend the boundary of the Wiener attack. Their result shows that the cost of exhaustive search is 2r+8 bits when extending the Weiner's boundary r bits. In this paper, we first reduce the cost of exhaustive search from 2r+8 bits to 2r+2 bits. Then, we propose a method named EPF. With EPF, the cost of exhaustive search is further reduced to 2r-6 bits when we extend Weiner's boundary r bits. It means that our result is 214 times faster than Verheul and van Tilborg's result. Besides, the security boundary is extended 7 bits.

  10. The clinical impact of a positive family history of psychosis or mental ...

    African Journals Online (AJOL)

    Background: A family history of psychosis is associated with negative clinical characteristics of psychosis. Aim: We aimed to determine the relationship between a family history (in first-degree relatives) of psychosis (FHP) or of any mental illness (FHM), and the clinical features (including cannabis use) of first episode early ...

  11. Factors associated with positive adjustment in siblings of children with severe emotional disturbance: the role of family resources and community life.

    Science.gov (United States)

    Kilmer, Ryan P; Cook, James R; Munsell, Eylin Palamaro; Salvador, Samantha Kane

    2010-10-01

    This study builds on the scant research involving siblings of children with severe emotional disturbances (SED) and examines: associations between adversity experiences and adjustment among 5- to 10-year-old siblings, and relations among family resources, community life, and sibling adjustment. Caregivers from 100 families completed standardized indicators of sibling adjustment and scales reflecting multiple contextual variables. Results document negative associations between stress exposure and sibling adjustment. Regression models also indicate positive associations between the caregiver-child relationship and broader family resources on sibling behavioral and emotional strengths, even after accounting for adversity experiences; adversity exposure was the prime correlate in regression models involving sibling oppositional behavior. Analyses also suggest that strain related to parenting a child with SED is associated with sibling adjustment. This work documents the needs of these siblings and their family systems and highlights the relevance of not only core proximal influences (e.g., child-caregiver relationship) but also elements of their broader contexts. Implications and recommendations are described, including the need to support plans of care that involve services, supports, or preventive strategies for these siblings. © 2010 American Orthopsychiatric Association.

  12. A structural model of family empowerment for families of children with special needs.

    Science.gov (United States)

    Han, Kuem Sun; Yang, Yunkyung; Hong, Yeong Seon

    2018-03-01

    To explain and predict family empowerment in families of children with special needs. Family empowerment of families of children with special needs can be explained using the Double ABCX model. Although constant stressors such as parenting stress and family demands can have negative effects on family empowerment, family resources and parenting efficacy can mediate the negative effect through effective coping strategies. A cross-sectional research design was employed. A survey was conducted with 240 parents of children with special needs. Upon exclusion of four responses deemed inadequate to the statistics process, 236 responses were selected for the analysis. Based on the items used in the previous research, we used the scale of family demands 38, the scale of parenting stress 24, the scale of parenting efficacy 37, the scale of pattern of organisation 30, the scale of communication process 16 and the scale of family empowerment 32. In families of children with special needs, parenting stress had a negative effect on parenting efficacy and family resources, namely, pattern of organisation and communication process. Family needs had a positive effect on parenting efficacy. Parenting stress and family demands influenced family empowerment through parenting efficacy and family resources (pattern of organisation and communication process), while parenting efficacy contributed to family empowerment. This study empirically analysed the usefulness of the Double ABCX model in predicting family empowerment. Family resource factors (organisation pattern and communication process) and perception or judgement factors (such as parenting efficacy) were found to mediate the negative impact of various stressors experienced by families of children with special needs. The study findings suggest that clinical practice and management should focus on providing efficient intervention methods to lower stress in families of children with special needs. Reinforcing factors contributing to

  13. Development and Two-Year Follow-Up Evaluation of a Training Workshop for the Large Preventive Positive Psychology Happy Family Kitchen Project in Hong Kong.

    Directory of Open Access Journals (Sweden)

    Agnes Y Lai

    Full Text Available Evidence-based practice and capacity-building approaches are essential for large-scale health promotion interventions. However, there are few models in the literature to guide and evaluate training of social service workers in community settings. This paper presents the development and evaluation of the "train-the-trainer" workshop (TTT for the first large scale, community-based, family intervention projects, entitled "Happy Family Kitchen Project" (HFK under the FAMILY project, a Hong Kong Jockey Club Initiative for a Harmonious Society. The workshop aimed to enhance social workers' competence and performance in applying positive psychology constructs in their family interventions under HFK to improve family well-being of the community they served. The two-day TTT was developed and implemented by a multidisciplinary team in partnership with community agencies to 50 social workers (64% women. It focused on the enhancement of knowledge, attitude, and practice of five specific positive psychology themes, which were the basis for the subsequent development of the 23 family interventions for 1419 participants. Acceptability and applicability were enhanced by completing a needs assessment prior to the training. The TTT was evaluated by trainees' reactions to the training content and design, changes in learners (trainees and benefits to the service organizations. Focus group interviews to evaluate the workshop at three months after the training, and questionnaire survey at pre-training, immediately after, six months, one year and two years after training were conducted. There were statistically significant increases with large to moderate effect size in perceived knowledge, self-efficacy and practice after training, which sustained to 2-year follow-up. Furthermore, there were statistically significant improvements in family communication and well-being of the participants in the HFK interventions they implemented after training. This paper offers a

  14. Development and Two-Year Follow-Up Evaluation of a Training Workshop for the Large Preventive Positive Psychology Happy Family Kitchen Project in Hong Kong.

    Science.gov (United States)

    Lai, Agnes Y; Mui, Moses W; Wan, Alice; Stewart, Sunita M; Yew, Carol; Lam, Tai-Hing; Chan, Sophia S

    2016-01-01

    Evidence-based practice and capacity-building approaches are essential for large-scale health promotion interventions. However, there are few models in the literature to guide and evaluate training of social service workers in community settings. This paper presents the development and evaluation of the "train-the-trainer" workshop (TTT) for the first large scale, community-based, family intervention projects, entitled "Happy Family Kitchen Project" (HFK) under the FAMILY project, a Hong Kong Jockey Club Initiative for a Harmonious Society. The workshop aimed to enhance social workers' competence and performance in applying positive psychology constructs in their family interventions under HFK to improve family well-being of the community they served. The two-day TTT was developed and implemented by a multidisciplinary team in partnership with community agencies to 50 social workers (64% women). It focused on the enhancement of knowledge, attitude, and practice of five specific positive psychology themes, which were the basis for the subsequent development of the 23 family interventions for 1419 participants. Acceptability and applicability were enhanced by completing a needs assessment prior to the training. The TTT was evaluated by trainees' reactions to the training content and design, changes in learners (trainees) and benefits to the service organizations. Focus group interviews to evaluate the workshop at three months after the training, and questionnaire survey at pre-training, immediately after, six months, one year and two years after training were conducted. There were statistically significant increases with large to moderate effect size in perceived knowledge, self-efficacy and practice after training, which sustained to 2-year follow-up. Furthermore, there were statistically significant improvements in family communication and well-being of the participants in the HFK interventions they implemented after training. This paper offers a practical example

  15. ANALISIS PENGARUH WORK-FAMILY BALANCE DAN PROGRAM FAMILY FRIENDLY TERHADAP KEPUASAN KERJA Studi Kasus pada Rumah Sakit Panti Wilasa Citarum, Semarang

    OpenAIRE

    Paloma Paramita; Waridin Waridin

    2007-01-01

    This research aim to test the impact of work-family balance and family friendly program to job satisfaction. The sample of the research are 75 nurses in Panti Wilasa Hospital by purposive sampling. Result of the research support hypotheses. First, work-family balance have positive impact to job satisfaction, second, family friendly program have positive impact to job satisfaction. Analyses in the research use multiple regression.

  16. Family history of cardiovascular events and endothelial dysfunction in children with familial hypercholesterolemia

    NARCIS (Netherlands)

    de Jongh, Saskia; Lilien, Marc R.; Bakker, Henk D.; Hutten, Barbara A.; Kastelein, John J. P.; Stroes, Erik S. G.

    2002-01-01

    Objectives: in patients with familial hypercholesterolemia (FH), the propensity towards atherosclerosis may vary considerably. In the general population, a positive family history is associated with an increased risk for cardiovascular events. Since endothelial dysfunction is predictive for future

  17. Application of the largest Lyapunov exponent and non-linear fractal extrapolation algorithm to short-term load forecasting

    International Nuclear Information System (INIS)

    Wang Jianzhou; Jia Ruiling; Zhao Weigang; Wu Jie; Dong Yao

    2012-01-01

    Highlights: ► The maximal predictive step size is determined by the largest Lyapunov exponent. ► A proper forecasting step size is applied to load demand forecasting. ► The improved approach is validated by the actual load demand data. ► Non-linear fractal extrapolation method is compared with three forecasting models. ► Performance of the models is evaluated by three different error measures. - Abstract: Precise short-term load forecasting (STLF) plays a key role in unit commitment, maintenance and economic dispatch problems. Employing a subjective and arbitrary predictive step size is one of the most important factors causing the low forecasting accuracy. To solve this problem, the largest Lyapunov exponent is adopted to estimate the maximal predictive step size so that the step size in the forecasting is no more than this maximal one. In addition, in this paper a seldom used forecasting model, which is based on the non-linear fractal extrapolation (NLFE) algorithm, is considered to develop the accuracy of predictions. The suitability and superiority of the two solutions are illustrated through an application to real load forecasting using New South Wales electricity load data from the Australian National Electricity Market. Meanwhile, three forecasting models: the gray model, the seasonal autoregressive integrated moving average approach and the support vector machine method, which received high approval in STLF, are selected to compare with the NLFE algorithm. Comparison results also show that the NLFE model is outstanding, effective, practical and feasible.

  18. The impact of war on Puerto Rican families: challenges and strengthened family relationships.

    Science.gov (United States)

    Magaly Freytes, I; Hannold, Elizabeth M; Resende, Rosana; Wing, Kristen; Uphold, Constance R

    2013-08-01

    We describe the impact of war on Puerto Rican Veterans and family members. We used qualitative research methods to collect and analyze data. We interviewed 8 Veterans and 8 family members. We used the constant comparison method to review data to identify prominent themes. Two categories emerged: (1) Challenges associated with post-deployment family reintegration, and (2) A positive aftermath of war on the family. Overall, findings indicate that OEF/OIF Veterans and family members were not prepared for the changes they encounter post-deployment. Despite these challenges, some Veterans and family members strengthened their relationships and renewed their appreciation for one another.

  19. Family-supportive organization perceptions and organizational commitment: the mediating role of work-family conflict and enrichment and partner attitudes.

    Science.gov (United States)

    Wayne, Julie Holliday; Casper, Wendy J; Matthews, Russell A; Allen, Tammy D

    2013-07-01

    The present study aims to explain the processes through which family-supportive organizational perceptions (FSOP) relate to employee affective commitment. We suggest multiple mechanisms through which this relationship transpires-(a) the focal employee's experience of work-to-family conflict and enrichment and (b) the attitudes of the employee's spouse/partner. Hypotheses are tested with data from 408 couples. Results suggest that employee FSOP is positively associated with employee commitment through both employee work-to-family experiences and partner attitudes. FSOP was positively related to employee work-to-family enrichment, which was positively associated with employee affective commitment. FSOP was negatively associated with employee work-to-family conflict, which related to a partner's more positive attitude toward the employee's work schedule and higher commitment to the employee's firm. Partner commitment was positively and reciprocally related to employee affective commitment. These relationships partially mediated the FSOP-employee affective commitment relationship and varied as a function of parental status and single- versus dual-earner couple status but not as a function of employee gender. Theoretical and practical implications are discussed. PsycINFO Database Record (c) 2013 APA, all rights reserved.

  20. Perceptions of Personal and Familial Adjustment by Children from Intact, Single-Parent, and Reconstituted Families.

    Science.gov (United States)

    Nunn, Gerald D.; And Others

    1983-01-01

    Investigated children's (N=566) personal and familial adjustment as a function of familial configuration and gender. The results revealed less positive adjustment among children from divorced families. Males appeared to be favorably affected within the single-parent configuration, while females were more favorably adjusted within the reconstituted…

  1. Family Dinners. For Parents Particularly.

    Science.gov (United States)

    Klein, Helen Altman

    2001-01-01

    Asserts that family dinners deserve attention as a positive contributor to children's well-being. Maintains that family dinners give stability to a potentially confusing day, present a place for children to express themselves, and provide children's first community. Includes ideas for helping families identify their own dinner patterns and…

  2. On the effects of surrogacy of energy dissipation in determining the intermittency exponent in fully developed turbulence

    Science.gov (United States)

    Cleve, J.; Greiner, M.; Sreenivasan, K. R.

    2003-03-01

    The two-point correlation function of the energy dissipation, obtained from a one-point time record of an atmospheric boundary layer, reveals a rigorous power law scaling with intermittency exponent μ approx 0.20 over almost the entire inertial range of scales. However, for the related integral moment, the power law scaling is restricted to the upper part of the inertial range only. This observation is explained in terms of the operational surrogacy of the construction of energy dissipation, which influences the behaviour of the correlation function for small separation distances.

  3. Characterizing Submonolayer Growth of 6P on Mica: Capture Zone Distributions vs. Growth Exponents and the Role of Hot Precursors

    Science.gov (United States)

    Einstein, T. L.; Morales-Cifuentes, Josue; Pimpinelli, Alberto

    2015-03-01

    Analyzing capture-zone distributions (CZD) using the generalized Wigner distribution (GWD) has proved a powerful way to access the critical nucleus size i. Of the several systems to which the GWD has been applied, we consider 6P on mica, for which Winkler's group found i ~ 3 . Subsequently they measured the growth exponent α (island density ~Fα , for flux F) of this system and found good scaling but different values at small and large F, which they attributed to DLA and ALA dynamics, but with larger values of i than found from the CZD analysis. We investigate this result in some detail. The third talk of this group describes a new universal relation between α and the characteristic exponent β of the GWD. The second talk reports the results of a proposed model that takes long-known transient ballistic adsorption into account, for the first time in a quantitative way. We find several intermediate scaling regimes, with distinctive values of α and an effective activation energy. One of these, rather than ALA, gives the best fit of the experimental data and a value of i consistent with the CZD analysis. Work at UMD supported by NSF CHE 13-05892.

  4. Work, family, and gender: elements for a theory of work-family balance.

    Science.gov (United States)

    Cantera, Leonor M; Cubells, Ma Eugenia; Martínez, Luz Ma; Blanch, Josep M

    2009-11-01

    Over last century, work was not only a means of economic survival, but also a very strong factor of psychological structuring and of organization of personal, family, and everyday life. The new world of work provides new challenges to the balance of work and family life. A questionnaire was administered to a sample of 453 people with the aim of analyzing the relation between variables such as family burdens and domestic responsibilities, and the appraisal of work and family, values involved in work-family balance. The results of this study show that, in the present economic and cultural context, assuming family burdens and domestic responsibilities increases the positive appraisal of work and family, both in men and women. This has theoretical and practical implications concerning the challenge of work-family balance.

  5. The relationship between family obligation and religiosity on caregiving.

    Science.gov (United States)

    Epps, Fayron

    2014-01-01

    The purpose of this study was to examine the relationship between family obligation and religiosity on the positive appraisal of caregiving among African-American, Hispanic and non-Hispanic Caucasian family caregivers of older adults. Roy's adaptation model guided formulation of the aims and study design. A cross-sectional, correlational study design was employed to examine the relationship amongst variables for the family caregiver participants. Study participants (N = 69) completed a demographic tool and four instruments the: (1) Katz index, (2) obligation scale, (3) Duke University religion index, and (4) positive appraisal of care scale. There was a significant correlation between family obligation and positive appraisal of caregiving. However, there was no relationship between the family caregiver's religiosity and positive appraisal of caregiving overall. Demographic variables were also examined to show a higher marginal mean for Hispanic primary caregivers in relation to the positive appraisal of caregiving. Future studies should consider replicating these findings in a larger sample to provide health care professionals with substantial evidence to incorporate culturally sensitive interventions aimed at promoting positive outcomes and healthy family behaviors. Copyright © 2014 Mosby, Inc. All rights reserved.

  6. Virtual walks in spin space: A study in a family of two-parameter models

    Science.gov (United States)

    Mullick, Pratik; Sen, Parongama

    2018-05-01

    We investigate the dynamics of classical spins mapped as walkers in a virtual "spin" space using a generalized two-parameter family of spin models characterized by parameters y and z [de Oliveira et al., J. Phys. A 26, 2317 (1993), 10.1088/0305-4470/26/10/006]. The behavior of S (x ,t ) , the probability that the walker is at position x at time t , is studied in detail. In general S (x ,t ) ˜t-αf (x /tα) with α ≃1 or 0.5 at large times depending on the parameters. In particular, S (x ,t ) for the point y =1 ,z =0.5 corresponding to the Voter model shows a crossover in time; associated with this crossover, two timescales can be defined which vary with the system size L as L2logL . We also show that as the Voter model point is approached from the disordered regions along different directions, the width of the Gaussian distribution S (x ,t ) diverges in a power law manner with different exponents. For the majority Voter case, the results indicate that the the virtual walk can detect the phase transition perhaps more efficiently compared to other nonequilibrium methods.

  7. A New Chaotic System with Positive Topological Entropy

    Directory of Open Access Journals (Sweden)

    Zhonglin Wang

    2015-08-01

    Full Text Available This paper introduces a new simple system with a butterfly chaotic attractor. This system has rich and complex dynamics. With some typical parameters, its Lyapunov dimension is greater than other known three dimensional chaotic systems. It exhibits chaotic behavior over a large range of parameters, and the divergence of flow of this system is not a constant. The dynamics of this new system are analyzed via Lyapunov exponent spectrum, bifurcation diagrams, phase portraits and the Poincaré map. The compound structures of this new system are also analyzed. By means of topological horseshoe theory and numerical computation, the Poincaré map defined for the system is proved to be semi-conjugate to 3-shift map, and thus the system has positive topological entropy.

  8. "There is still so much ahead of us"-family functioning in families of palliative cancer patients.

    Science.gov (United States)

    Kühne, Franziska; Krattenmacher, Thomas; Bergelt, Corinna; Beierlein, Volker; Herzog, Wolfgang; V Klitzing, Kai; Weschenfelder-Stachwitz, Heike; Romer, Georg; Möller, Birgit

    2013-06-01

    Adopting a systems approach, parental cancer has its impact on patients, spouses, and dependent children. The purpose of the current study was to examine family functioning dependent on parental disease stage and on family member perspective in families of cancer patients with adolescent children. The cross-sectional study was conducted within a German multisite research project of families before their first child-centered counseling encounter. The sample comprised individuals nested within N = 169 families. Analyses performed included analysis of covariance (ANCOVA) and intraclass correlation. Open answers were analyzed following quantitative content analysis procedures. Between 15% and 36% of family members reported dysfunctional general functioning scores. Parents indicated more dysfunctional scores on the Family Assessment Device scale Roles, and adolescents more dysfunctional Communication scores. Regarding assessment of family functioning, there was higher agreement in families with parents in a palliative situation. For adolescents with parents in palliation, incidents because of the disease tend to become more dominant, and spending time with the family tends to become even more important. As our study pointed out, parental cancer, and especially parental palliative disease, is associated with both perceived critical and positive aspects in family functioning. Supporting families in these concerns as well as encouraging perceptions of positive aspects are important components of psycho-oncological interventions for families with dependent children. PsycINFO Database Record (c) 2013 APA, all rights reserved.

  9. The Enhanced Aussie Optimism Positive Thinking Skills Program: Assessing the relationship between internalising symptoms and family functioning in children aged 9-11 years of age

    Directory of Open Access Journals (Sweden)

    Patricia eKennedy

    2015-04-01

    Full Text Available The family context plays a critical role in the health of the child. This was the first study to examine the usefulness of the General Functioning subscale of the Family Assessment Device (FAD-GF in assessing family functioning and its relationship to internalising symptoms in school-aged children aged between 9 and 11 years of age. Eight hundred and forty-seven Year 4 and 5 students from 13 schools (607 intervention students, and 240 control students participated in the Aussie Optimism Positive Thinking Skills Program (AO-PTS - a universal school-based program targeting internalising symptoms. Students rated how ‘healthy’ they perceived their family to be at pre-test and at 6-month follow-up. Although some aspects of validity and reliability could be improved, results indicated that perceptions of family functioning at pre-test were predictive of internalising symptoms at the 6-month follow-up. The FAD-GF therefore showed promise as a potential measure of family functioning for children as young as nine years old. Regardless of children’s pre-test levels of perceived family functioning, no intervention effects were found on the anxiety and depression scales; this finding suggests that child perceptions of family functioning may act as a general protective factor against internalising symptomology.

  10. FAMILIAL AMYLOID POLYNEUROPATHY——CLINICAL REPORT OF A FAMILY

    Institute of Scientific and Technical Information of China (English)

    李延峰; 郭玉璞; 池田修一; 方定华

    1996-01-01

    This paper reports a familial amyloid polyneumpathy (FAP) family in China. This family being investigated had 69 members of five generations. From the third generation, there have been 16 patients. The age of onset was about 3 to 5 decades. The initial symptoms were autonomic nerve symptcans, such as impotence, dyspepaia and diarrhoea, associated with the sensory loss of lower extremities. As the disease progressed. the upper extremities and motor ability were also involved. The duration of disease course wasabout 8-10 years, most patients died of infection and cacbexia. Sural biopsy in 3 patients had showed positive Congo red staining. From the clinical view, this FAP family is similar to FAP I found in Japan. Thetrue classification, however, should be confirmed by further genetic analysis.

  11. The Role of Identity and Work-Family Support in Work-Family Enrichment and Its Work-Related Consequences

    Science.gov (United States)

    Wayne, Julie Holliday; Randel, Amy E.; Stevens, Jaclyn

    2006-01-01

    Despite growing research on the positive connections between work and family, antecedents and consequences of work-family enrichment are understudied. Using a sample of employees from a major insurance company, we assessed the relationship of (i) individual (i.e., work and family identities), (ii) family (emotional and instrumental support), and…

  12. Family history of premature myocardial infarction, life course socioeconomic position and coronary heart disease mortality--A Cohort of Norway (CONOR) study.

    Science.gov (United States)

    Fiskå, Bendik S; Ariansen, Inger; Graff-Iversen, Sidsel; Tell, Grethe S; Egeland, Grace M; Næss, Øyvind

    2015-01-01

    To investigate self-reported family history (FH) of premature myocardial infarction (MI) in first-degree relatives as a risk factor for coronary heart disease (CHD) mortality, and assess whether any observed effect could be explained by current or life course socioeconomic position. 130,066 participants from Cohort of Norway were examined during 1994-2003. A subgroup (n=84,631) had additional life course socioeconomic data. Using Cox proportional hazard analyses, we calculated hazard ratios (HR) for CHD mortality, assessed by linkages to the Norwegian Cause of Death Registry through 2009. For subgroup analyses, we created an index of life course socioeconomic position, and assessed its role as a potential confounder in the association of FH with CHD. For men, MI in parents and siblings were both a significant risk factor for CHD mortality after adjusting for established risk factors and current socioeconomic conditions; the highest risk was with MI in siblings (HR: 1.44 [1.19-1.75]). For women, FH constituted significant risk after similar adjustment only for those with MI in parents plus siblings (HR: 1.78 [1.16-2.73]). Adjusting for current and life course socioeconomic conditions only marginally lowered the estimates, and those with FH did not have worse life course socioeconomic position than those without. FH of premature MI is an independent risk factor for CHD mortality that differs in magnitude of effect by the sex of the index person and type of familial relationship. Life course socioeconomic position has little impact on the association between FH and CHD, suggesting the effect is not confounded by this. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  13. Life in Remarriage Families.

    Science.gov (United States)

    Dahl, Ann Sale; And Others

    1987-01-01

    In preliminary findings from research interviews with nonclinical remarriage families who were not receiving treatment, both marital satisfaction and children's adjustment were described in primarily positive terms, especially after the first few years. Families reported that the process of managing complexities, uncertainties, and mixed feelings…

  14. Daily positive spillover and crossover from mothers' work to youth health.

    Science.gov (United States)

    Lawson, Katie M; Davis, Kelly D; McHale, Susan M; Hammer, Leslie B; Buxton, Orfeu M

    2014-12-01

    Prior research shows that employees' work experiences can "spill over" into their family lives and "cross over" to affect family members. Expanding on studies that emphasize negative implications of work for family life, this study examined positive work-to-family spillover and positive and negative crossover between mothers and their children. Participants were 174 mothers in the extended care (nursing home) industry and their children (ages 9-17), both of whom completed daily diaries on the same 8 consecutive evenings. On each workday, mothers reported whether they had a positive experience at work, youth reported on their mothers' positive and negative mood after work, and youth rated their own mental (positive and negative affect) and physical health (physical health symptoms, sleep quality, sleep duration). Results of 2-level models showed that mothers' positive mood after work, on average, was directly related to youth reports of more positive affect, better sleep quality, and longer sleep duration. In addition, mothers with more positive work experiences, on average, displayed less negative mood after work, and in turn, adolescents reported less negative affect and fewer physical health symptoms. Results are discussed in terms of daily family system dynamics.

  15. Daily Positive Spillover and Crossover from Mothers’ Work to Youth Health

    Science.gov (United States)

    Lawson, Katie M.; Davis, Kelly D.; McHale, Susan M.; Hammer, Leslie B.; Buxton, Orfeu M.

    2016-01-01

    Prior research shows that employees’ work experiences can “spill over” into their family lives and “cross over” to affect family members. Expanding on studies that emphasize negative implications of work for family life, this study examined positive work-to-family spillover and positive and negative crossover between mothers and their children. Participants were 174 mothers in the extended care (nursing home) industry and their children (ages 9-17), both of whom completed daily diaries on the same, eight, consecutive evenings. On each workday, mothers reported whether they had a positive experience at work, youth reported on their mothers’ positive and negative mood after work, and youth rated their own mental (positive and negative affect) and physical health (physical health symptoms, sleep quality, sleep duration). Results of two-level models showed that mothers’ positive mood after work, on average, was directly related to youth reports of more positive affect, better sleep quality, and longer sleep duration. In addition, mothers with more positive work experiences, on average, displayed less negative mood after work, and in turn, adolescents reported less negative affect and fewer physical health symptoms. Results are discussed in terms of daily family system dynamics. PMID:25243577

  16. ANTHIM THE IVIRITE AN EXPONENT OF CAUCASIAN AND ROMANIAN SPIRITUALITY IN THE 18TH CENTURY

    Directory of Open Access Journals (Sweden)

    Angela BOTEZ

    2016-10-01

    Full Text Available The paper approaches the theme about Anthim the Ivirite is an exponent of Romanian and Caucasian spirituality. Honouring this personality we start from the observation that his spiritual heritage remains relevant over the ages. Some biographers claim that Anthim the Ivirite was from a noble family. His life was as well dramatic, as noble. Anthim the Ivirite remains in Romanian history as a deeply religious man and a man of many talents. He spoke several foreign languages among which Romanian, Greek, Arabic and Turkish. Saint Anthim was a scholar, a printer of religious writings, he wrote religious literature and succeeded to leave a deep mark in the Romanian culture that times undimmed. We consider relevant also that among the important anniversaries of the year 2016 along with the anniversary of Saint Anthim the Ivirite the Romanian Orthodox Church celebrates all the Romanian Church typographers who have contributed fundamentally to a rich religious culture in Romanian. A religious journalist notice for a specialized publication that The fact that the Romanian Orthodox Church, under the clear vision of His Beatitude Patriarch Daniel has chosen to inscribe amongst the paramount holidays of the year 2016 the Church typographers represents a memorable and soul-uplifting gesture, a gesture of conscience in agreement with all who wanted and succeeded to conquer time through the eternity of the typed letter, taking the Word of God in all the four skies and seeding the values of Christian faith and Christian moral in the hearts and thoughts of all Romanians. Posterity’s judgment was warm, respectful and fair in what concerns Saint Hierarch Anthim, and the Holy Synod of the Romanian Orthodox Church glorified him, as a saint and martyr of our Romanian Orthodox Church and this is the reason why the final part of the paper is dedicated to the identification of a string of interesting Anthim anniversaries over the times.

  17. Perceptions of community and family level IDU and HIV related stigma, disclosure decisions and experiences with layered stigma among HIV positive injection drug users in Vietnam

    OpenAIRE

    Rudolph, A.E.; Davis, W.W.; Quan, V.M.; Ha, T.V.; Minh, N.L.; Gregowski, A.; Salter, Megan; Celentano, D.D.; Go, V.

    2011-01-01

    This paper explores how perceived stigma and layered stigma related to injection drug use and being HIV positive influence the decision to disclose one’s HIV status to family and community and experiences with stigma following disclosure among a population of HIV positive male injection drug users (IDUs) in Thai Nguyen, Vietnam. In qualitative interviews conducted between 2007 and 2008, 25 HIV positive male IDUs described layered stigma in their community but an absence of layered stigma with...

  18. Risk-taking behavior in private family firms: the role of the non-family CEO

    OpenAIRE

    Huybrechts, Jolien; Voordeckers, Wim; Lybaert, Nadine; Vandemaele, Sigrid

    2011-01-01

    This paper studies the risk-taking behavior of private family firms in general as well as variations in risk-taking behavior among the group of family firms. We use the agency perspective to theoretically argue that the usually high degree of coupling of ownership and management causes family firms to be on average less risk-taking than non-family firms. The introduction of a non-family CEO who usually has no or only limited legal ownership will have a positive influence on the level of risk-...

  19. Wavefunctions, quantum diffusion, and scaling exponents in golden-mean quasiperiodic tilings

    International Nuclear Information System (INIS)

    Thiem, Stefanie; Schreiber, Michael

    2013-01-01

    We study the properties of wavefunctions and the wavepacket dynamics in quasiperiodic tight-binding models in one, two, and three dimensions. The atoms in the one-dimensional quasiperiodic chains are coupled by weak and strong bonds aligned according to the Fibonacci sequence. The associated d-dimensional quasiperiodic tilings are constructed from the direct product of d such chains, which yields either the hypercubic tiling or the labyrinth tiling. This approach allows us to consider fairly large systems numerically. We show that the wavefunctions of the system are multifractal and that their properties can be related to the structure of the system in the regime of strong quasiperiodic modulation by a renormalization group (RG) approach. We also study the dynamics of wavepackets to get information about the electronic transport properties. In particular, we investigate the scaling behaviour of the return probability of the wavepacket with time. Applying again the RG approach we show that in the regime of strong quasiperiodic modulation the return probability is governed by the underlying quasiperiodic structure. Further, we also discuss lower bounds for the scaling exponent of the width of the wavepacket and propose a modified lower bound for the absolute continuous regime.

  20. Wavefunctions, quantum diffusion, and scaling exponents in golden-mean quasiperiodic tilings.

    Science.gov (United States)

    Thiem, Stefanie; Schreiber, Michael

    2013-02-20

    We study the properties of wavefunctions and the wavepacket dynamics in quasiperiodic tight-binding models in one, two, and three dimensions. The atoms in the one-dimensional quasiperiodic chains are coupled by weak and strong bonds aligned according to the Fibonacci sequence. The associated d-dimensional quasiperiodic tilings are constructed from the direct product of d such chains, which yields either the hypercubic tiling or the labyrinth tiling. This approach allows us to consider fairly large systems numerically. We show that the wavefunctions of the system are multifractal and that their properties can be related to the structure of the system in the regime of strong quasiperiodic modulation by a renormalization group (RG) approach. We also study the dynamics of wavepackets to get information about the electronic transport properties. In particular, we investigate the scaling behaviour of the return probability of the wavepacket with time. Applying again the RG approach we show that in the regime of strong quasiperiodic modulation the return probability is governed by the underlying quasiperiodic structure. Further, we also discuss lower bounds for the scaling exponent of the width of the wavepacket and propose a modified lower bound for the absolute continuous regime.

  1. Family-based processes associated with adolescent distress, substance use and risky sexual behavior in families affected by maternal HIV.

    Science.gov (United States)

    Lester, Patricia; Stein, Judith A; Bursch, Brenda; Rice, Eric; Green, Sara; Penniman, Typhanye; Rotheram-Borus, Mary Jane

    2010-01-01

    The present study investigated how maternal HIV and mediating family processes are associated with adolescent distress, substance use, and risky sexual behavior. Mother-adolescent (ages 12-21) dyads (N = 264) were recruited from neighborhoods where the HIV-affected families resided (161 had mothers with HIV). Mediating family processes were youth aggressive conflict style, maternal bonding, maternal role reversal expectations, and overall family functioning. Results of structural equation modeling indicated that youth aggressive conflict resolution style was strongly associated with adolescent distress, substance use, and risky sexual behavior. In HIV-affected families, youth less frequently reported using an aggressive conflict resolution style and more frequently reported positive maternal bonds; their mothers reported less positive family functioning than control families. Finally, maternal distress indirectly affected adolescent distress and risk behavior via youth aggressive conflict resolution style.

  2. Do family CEOs impact firm value? An empirical analysis of Indian family firms

    Directory of Open Access Journals (Sweden)

    Lakshmi Kalyanaraman

    2015-01-01

    Full Text Available We study the association between family CEO and firm value on a sample of 288 family firms during the 6-year period, from 2009 to 2014. The sample is drawn from domestic private companies belonging to non-financial services sector included in the NSE CNX 500 index. We find that family CEO has no significant association with firm value, when the family is not the majority shareholder. Family shareholding has positive relationship with firm value, but does not moderate the relationship of family CEO with firm value. We show that family CEO and firm value are negatively related when the family does not hold majority equity stake in the family firm. While family shareholding has no significant relationship with firm value, it has a negative interaction effect on the relationship between family CEO and firm value. The research findings have important implications for family firms as well as the nonfamily investors in the family firms.

  3. NASA Family Science Night: Changing perceptions one family at a time

    Science.gov (United States)

    Mitchell, Sara E.; Drobnes, Emilie; Sol Colina-Trujillo, M.; Noel-Storr, Jacob

    2008-12-01

    Parents and families have the greatest influence on children's attitudes towards education and career choices. If students' attitudes towards science, particularly the physical sciences, are not influenced positively by parental/familial attitudes, efforts to improve the quality of content and teaching of these subjects in school may be futile. Research shows that parental involvement increases student achievement outcomes, and family-oriented programs have a direct impact on student performance. Based on this premise, the NASA Goddard Space Flight Center started a series of Family Science Nights for middle school students and their families. The program provides a non-threatening venue for families to explore the importance of science and technology in our daily lives by engaging in learning activities that change their perception and understanding of science - making it more practical and approachable for participants of all ages. Family Science Night strives to change the way that students and their families participate in science, within the program and beyond.

  4. Work-Family facilitation : a positive psychological perspective on role combination

    NARCIS (Netherlands)

    Steenbergen, Elianne Florence van

    2007-01-01

    This dissertation provides a balanced picture of the experiences that individuals can have in the combination of their work and family roles. Extending the common focus in previous literature on experiences of role conflict (and their detrimental consequences), the present research also addresses

  5. A systematic review of the literature on family functioning across all eating disorder diagnoses in comparison to control families.

    Science.gov (United States)

    Holtom-Viesel, Anita; Allan, Steven

    2014-02-01

    The objectives of this review were to systematically identify and evaluate quantitative research comparing family functioning (a) in eating disorder families with control families, (b) in families with different eating disorder diagnoses (c) perceptions of different family members and (d) the relationship between family functioning and recovery. This adds to the findings of previous reviews of family functioning by including data from control families, the range of diagnoses, and focusing on recovery. Findings were considered in relation to models of family functioning. Using specific search criteria, 17 research papers were identified and evaluated. Findings indicated that eating disorder families reported worse family functioning than control families but there was little evidence for a typical pattern of family dysfunction. A consistent pattern of family dysfunction for different diagnoses was not suggested but patients consistently rated their family as more dysfunctional than one or both of their parents. With respect to outcome and recovery, those with more positive perceptions of family functioning generally had more positive outcomes, irrespective of severity of eating disorder. Conclusions were limited by inconsistent findings and methodological issues. Further research is needed into the relationship between family functioning and outcome and the assessment of family functioning beyond self-report. © 2013.

  6. Perception of family emotional climate by family members of persons with schizophrenia.

    Science.gov (United States)

    Gandhi, Sailaxmi; Pavalur, Rajitha; Thirthalli, Jagadisha; Phillip, Mariamma

    2016-08-01

    There is a dearth of instruments to assess schizophrenia persons' Family Emotional Climate (FEC). This study aims to explore the relation between family members' personality traits and FEC. We invited a convenience sample of 50 both gender family members who were accompanying the person with schizophrenia for out-patient department (OPD) consultation to provide data on a socio-demographic proforma and the researcher prepared 'Emotional climate assessment questionnaire - caregivers' version' (ECAQ-C) as well as the Eysenck personality questionnaire. Caregivers' extroversion traits (r = .427, p = .002) were positively correlated and neuroticism traits were negatively correlated (r = -.330, p = .019) with their positive perception of FEC. There was a higher perception of positive FEC (mean scores = 65.5 ± 10.5) while caregivers seemed to perceive less negative FEC (mean scores = 36.5 ± 10.2). Caregivers with education above 11th std perceived less (χ(2) = 8.6, p = .013) of negative FEC. The findings highlight that caregivers' personality traits seem to influence the FEC. While caregivers' perception of FEC is positive in this study, those in the higher education group seem to have a better perception of FEC indicating that education also may influence FEC. © The Author(s) 2016.

  7. Gradual multifractal reconstruction of time-series: Formulation of the method and an application to the coupling between stock market indices and their Hölder exponents

    Science.gov (United States)

    Keylock, Christopher J.

    2018-04-01

    A technique termed gradual multifractal reconstruction (GMR) is formulated. A continuum is defined from a signal that preserves the pointwise Hölder exponent (multifractal) structure of a signal but randomises the locations of the original data values with respect to this (φ = 0), to the original signal itself(φ = 1). We demonstrate that this continuum may be populated with synthetic time series by undertaking selective randomisation of wavelet phases using a dual-tree complex wavelet transform. That is, the φ = 0 end of the continuum is realised using the recently proposed iterated, amplitude adjusted wavelet transform algorithm (Keylock, 2017) that fully randomises the wavelet phases. This is extended to the GMR formulation by selective phase randomisation depending on whether or not the wavelet coefficient amplitudes exceeds a threshold criterion. An econophysics application of the technique is presented. The relation between the normalised log-returns and their Hölder exponents for the daily returns of eight financial indices are compared. One particularly noticeable result is the change for the two American indices (NASDAQ 100 and S&P 500) from a non-significant to a strongly significant (as determined using GMR) cross-correlation between the returns and their Hölder exponents from before the 2008 crash to afterwards. This is also reflected in the skewness of the phase difference distributions, which exhibit a geographical structure, with Asian markets not exhibiting significant skewness in contrast to those from elsewhere globally.

  8. Generalized Hurst exponent estimates differentiate EEG signals of healthy and epileptic patients

    Science.gov (United States)

    Lahmiri, Salim

    2018-01-01

    The aim of our current study is to check whether multifractal patterns of the electroencephalographic (EEG) signals of normal and epileptic patients are statistically similar or different. In this regard, the generalized Hurst exponent (GHE) method is used for robust estimation of the multifractals in each type of EEG signals, and three powerful statistical tests are performed to check existence of differences between estimated GHEs from healthy control subjects and epileptic patients. The obtained results show that multifractals exist in both types of EEG signals. Particularly, it was found that the degree of fractal is more pronounced in short variations of normal EEG signals than in short variations of EEG signals with seizure free intervals. In contrary, it is more pronounced in long variations of EEG signals with seizure free intervals than in normal EEG signals. Importantly, both parametric and nonparametric statistical tests show strong evidence that estimated GHEs of normal EEG signals are statistically and significantly different from those with seizure free intervals. Therefore, GHEs can be efficiently used to distinguish between healthy and patients suffering from epilepsy.

  9. Do Family Responsibilities and a Clinical Versus Research Faculty Position Affect Satisfaction with Career and Work–Life Balance for Medical School Faculty?

    Science.gov (United States)

    Beckett, Laurel; Nettiksimmons, Jasmine; Howell, Lydia Pleotis

    2015-01-01

    Abstract Background: Balancing career and family obligations poses challenges to medical school faculty and contributes to dissatisfaction and attrition from academics. We examined the relationship between family setting and responsibilities, rank, and career and work–life satisfaction for faculty in a large U.S. medical school. Methods: Baseline faculty surveys were analyzed from the first year of a 4-year National Institutes of Health–funded study to evaluate awareness, knowledge, attitudes, and use of family friendly policies and career satisfaction. The study focus was on the impact of family responsibilities and characteristics of the faculty position (rank, clinical vs. nonclinical, and academic series) in multivariate comparisons between primary predictors and outcomes of interest. Results: Both clinical and family responsibilities for children under 18 play a major and interacting role in satisfaction with career and work–life balance. Clinical faculty respondents without children at home reported significantly greater career satisfaction and better work–life balance than their nonclinical counterparts. Nonclinical faculty respondents with children reported greater satisfaction and better balance than counterparts without family responsibilities. However, the advantage in career satisfaction and work–life balance for clinical faculty respondents disappeared for those with responsibility for young children. No gender-based differences were noted in the results or across faculty rank for respondents; however, for women, reaching associate professor resulted in greater career satisfaction. Conclusion: This study suggests that both work-related factors and family responsibilities influence satisfaction with career and work–life balance, but the predictors appear to interact in complex and nuanced ways. Further research is needed to delineate more clearly these interactions and to explore other factors that may play important additional roles. PMID

  10. Do Family Responsibilities and a Clinical Versus Research Faculty Position Affect Satisfaction with Career and Work-Life Balance for Medical School Faculty?

    Science.gov (United States)

    Beckett, Laurel; Nettiksimmons, Jasmine; Howell, Lydia Pleotis; Villablanca, Amparo C

    2015-06-01

    Balancing career and family obligations poses challenges to medical school faculty and contributes to dissatisfaction and attrition from academics. We examined the relationship between family setting and responsibilities, rank, and career and work-life satisfaction for faculty in a large U.S. medical school. Baseline faculty surveys were analyzed from the first year of a 4-year National Institutes of Health-funded study to evaluate awareness, knowledge, attitudes, and use of family friendly policies and career satisfaction. The study focus was on the impact of family responsibilities and characteristics of the faculty position (rank, clinical vs. nonclinical, and academic series) in multivariate comparisons between primary predictors and outcomes of interest. Both clinical and family responsibilities for children under 18 play a major and interacting role in satisfaction with career and work-life balance. Clinical faculty respondents without children at home reported significantly greater career satisfaction and better work-life balance than their nonclinical counterparts. Nonclinical faculty respondents with children reported greater satisfaction and better balance than counterparts without family responsibilities. However, the advantage in career satisfaction and work-life balance for clinical faculty respondents disappeared for those with responsibility for young children. No gender-based differences were noted in the results or across faculty rank for respondents; however, for women, reaching associate professor resulted in greater career satisfaction. This study suggests that both work-related factors and family responsibilities influence satisfaction with career and work-life balance, but the predictors appear to interact in complex and nuanced ways. Further research is needed to delineate more clearly these interactions and to explore other factors that may play important additional roles.

  11. Mental Health of Children Living in Foster Families in Rural Rwanda: The Role of HIV and the Family Environment.

    Science.gov (United States)

    Nduwimana, Estella; Mukunzi, Sylvere; Ng, Lauren C; Kirk, Catherine M; Bizimana, Justin I; Betancourt, Theresa S

    2017-06-01

    Fostering children is common in sub-Saharan Africa, but few studies examine these children's mental health needs. This study investigated the impact of living in a foster family on the mental health of HIV-positive, HIV-affected and HIV-unaffected children (n = 681 aged 10-17) in rural Rwanda. Regression analyses assessed the impact of living in a foster family on mental health, parenting, and daily hardships; multiple mediation analyses assessed whether family factors mediated the association between foster status and mental health. HIV-positive children were eight times more likely to live in foster families than HIV-unaffected children. Being HIV-affected was predictive of depression and irritability symptoms after controlling for family factors. Controlling for HIV-status, foster children had more symptoms of depression, anxiety, and irritability than non-fostered children. Positive parenting fully mediated the association between foster status and mental health. Mental health and parenting interventions for foster children and HIV-affected children may improve child outcomes.

  12. FAKTOR-FAKTOR PENYIMPANGAN POSITIF (POSITIVE DEVIANCE STATUS GIZI BALITA PADA KELUARGA MISKIN DI KABUPATEN GIZI-KURANG RENDAH DAN TINGGI DI PROVINSI SULAWESI SELATAN (FACTORS OF POSITIVE DEVIANCE IN NUTRITIONAL STATUS OF UNDER-FIVES AMONG POOR FAMILY

    Directory of Open Access Journals (Sweden)

    Erna Luciasari

    2013-07-01

    Full Text Available ABSTRACT Background: The amount of poor population in Jeneponto & Selayar districts, South Sulawesi, were relatively similar and higher than the national average. However, Janeponto had high prevalence in malnutrition among children under five (28%, whereas Selayar had low prevalence in malnutrition among children under five (11,31%. Objective: This research aims to measure positive deviance which affects nutrition status in two different districts with relative-similar poverty level as well as different nutrition deficiency prevalence. Method: This research is an advance analysis of Riskesdas 2007 data which targeted poor family with under-five-children as sample. As the first step, data verification is conducted to make sure data completeness. Analysis is done by using statistical description, whereas Chi square test is used to analyzing nutrition-status-factors difference between two districts. Result: Under-five-children nutrition status is highly affected by family socio-economy status which covers education level of parents, income, total of family member, access to clean water, environment hygiene and sanitation, and family morbidity. Conclusion: Positive deviation factor of less malnutrition nutritional status than high malnutrition in poor areas was the high parental education, the small number of household members, and ease of access to water.   Keywords: positive deviance, nutritional status, under-fives, poor family   ABSTRAK Latar Belakang: Penduduk miskin di Kabupaten Jeneponto dan Selayar, Sulawesi Selatan, jumlahnya relatif sama dan lebih tinggi dari angka nasional. Namun, Jeneponto memiliki prevalensi balita gizi-kurang yang tinggi (28%, sedangkan Selayar memiliki prevalensi balita gizi-kurang yang rendah (11,3%. Tujuan: Menentukan faktor-faktor penyimpangan positif yang memengaruhi status gizi di dua kabupaten dengan tingkat kemiskinan relatif sama tetapi berprevalensi gizi kurang berbeda. Metode: Analisis lanjut data

  13. Understanding the Strengths of African American Families.

    Science.gov (United States)

    Littlejohn-Blake, Sheila M.; Darling, Carol Anderson

    1993-01-01

    Focuses on strengths of African-American families and how they function, relevant conceptual approaches, and trends and issues in studying African-American families that can facilitate understanding. A shift from studying dysfunctional families to more positive aspects can help African-American families meet societal challenges. (SLD)

  14. Solar System constraints on massless scalar-tensor gravity with positive coupling constant upon cosmological evolution of the scalar field

    Science.gov (United States)

    Anderson, David; Yunes, Nicolás

    2017-09-01

    Scalar-tensor theories of gravity modify general relativity by introducing a scalar field that couples nonminimally to the metric tensor, while satisfying the weak-equivalence principle. These theories are interesting because they have the potential to simultaneously suppress modifications to Einstein's theory on Solar System scales, while introducing large deviations in the strong field of neutron stars. Scalar-tensor theories can be classified through the choice of conformal factor, a scalar that regulates the coupling between matter and the metric in the Einstein frame. The class defined by a Gaussian conformal factor with a negative exponent has been studied the most because it leads to spontaneous scalarization (i.e. the sudden activation of the scalar field in neutron stars), which consequently leads to large deviations from general relativity in the strong field. This class, however, has recently been shown to be in conflict with Solar System observations when accounting for the cosmological evolution of the scalar field. We here study whether this remains the case when the exponent of the conformal factor is positive, as well as in another class of theories defined by a hyperbolic conformal factor. We find that in both of these scalar-tensor theories, Solar System tests are passed only in a very small subset of coupling parameter space, for a large set of initial conditions compatible with big bang nucleosynthesis. However, while we find that it is possible for neutron stars to scalarize, one must carefully select the coupling parameter to do so, and even then, the scalar charge is typically 2 orders of magnitude smaller than in the negative-exponent case. Our study suggests that future work on scalar-tensor gravity, for example in the context of tests of general relativity with gravitational waves from neutron star binaries, should be carried out within the positive coupling parameter class.

  15. Narrative Identity of Adolescents and Family Functioning

    Directory of Open Access Journals (Sweden)

    Cierpka Anna

    2014-11-01

    Full Text Available The paper presents research conducted within the narrative psychology paradigm. Its main purpose was to explore the relationships between features of adolescents’ identity narratives and their assessments of family functioning and themselves as family members. The choice of subject was motivated by current reports on identity formation difficulties in adolescence. Adolescents’ narratives were subjected to quantitative and qualitative analysis. Associations between specific aspects of self-narratives and participants’ perceptions of how their families functioned and how they functioned in the family system were evaluated. The results confirm the hypothesized relationships between the features of adolescents’ narratives and evaluations of their families and self-assessments of their own functioning in those families. Multi-thematic, content-rich and positively evaluated self-narratives are associated with positive assessments of selected aspects of family functioning and adolescents’ own functioning within the family. The following aspects of family assessment are significant: affective expression, level of emotional involvement in the family, level of control, family role performance and communication. Important factors in the self-assessment were: sense of competence in family role performance, assessment of one’s communication, behavior control and affective expression.

  16. Family history influences the early onset of hepatocellular carcinoma

    Institute of Scientific and Technical Information of China (English)

    Chung-Hwa Park; Seung-Hee Jeong; Hyeon-Woo Yim; Jin Dong Kim; Si Hyun Bae; Jong Young Choi; Seung Kew Yoon

    2012-01-01

    AIM:To evaluate the relationship between a positive family history of primary liver cancer and hepatocellular carcinoma (HCC) development in Korean HCC patients.METHODS:We studied a total of 2242 patients diagnosed with HCC between January 1990 and July 2008,whose family history of primary liver cancer was clearly described in the medical records.RESULTS:Of the 2242 patients,165 (7.4%) had a positive family history of HCC and 2077 (92.6%) did not.The male to female ratio was 3.6:1,and the major causes of HCC were chronic hepatitis B virus (HBV) infection in 75.1%,chronic hepatitis C virus infection in 13.2% and alcohol in 3.1%.The median ages at diagnosis in the positive-and negative-history groups were 52 years (range:29-79 years) and 57 years (range:18-89 years),respectively (P < 0.0001).Furthermore,among 1713 HCC patients with HBV infection,the number of patients under 45 years of age out of 136 patients with positive family history was 26 (19.1%),whereas those out of 1577 patients with negative family history was 197 (12.5%),suggesting that a positive family history may be associated with earlier development of HCC in the Korean population (P =0.0028).CONCLUSION:More intensive surveillance maybe recommended to those with a positive family history of HCC for earlier diagnosis and proper management especially when HBV infection is present.

  17. It's A Family Affair: Reflections About Aging and Health Within a Family Context.

    Science.gov (United States)

    Utz, Rebecca L; Berg, Cynthia A; Butner, Jonathan

    2017-02-01

    One's health and aging cannot be uncoupled from the family system in which it occurs. Not only do families provide genetic material that determines major health risks and outcomes, families also share a culture, environment, and lifestyle that further influence health and aging trajectories. As well, family members are interconnected, so that an illness or a positive lifestyle change in one person can have reverberating effects on the health and well-being of others in the family system. This essay explores how families have the potential to both promote and threaten individual health and well-being, thereby influencing how an individual might age or experience later life. Weaving together personal biographies from three different authors, this essay provides specific examples of how the family affects the health and aging of individuals and how the health and aging of individuals affect the larger family unit. These dynamic processes have the potential to positively or negatively shape individual experiences of health and aging, even among those persons who are not yet in late life. This essay blends a developmental life course perspective with a dynamic family-systems approach to show how families engage in collaborative efforts throughout the life course, in which they both affect and are affected by the diagnosis and management of chronic diseases and the adoption of health promoting behaviors. Applying this perspective to the study of health and aging calls for interdisciplinary thinking, as well as novel methodological and quantitative solutions. © The Author 2016. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  18. Brief Strategic Family Therapy: Engaging Drug Using/Problem Behavior Adolescents and their Families into Treatment

    Science.gov (United States)

    Szapocznik, José; Zarate, Monica; Duff, Johnathan; Muir, Joan

    2013-01-01

    Despite the efficacy of family-based interventions for improving outcomes for adolescent behavior problems such as substance use, engaging and retaining whole families in treatment is one of the greatest challenges therapists confront. This article illustrates how the Brief Strategic Family Therapy® (BSFT®) model, a family-based, empirically validated intervention designed to treat children and adolescents’ problem behaviors, can be used to increase engagement, improve retention, and bring about positive outcomes for families. Research evidence for efficacy and effectiveness is also presented. PMID:23731415

  19. LnqR, a TetR-family transcriptional regulator, positively regulates lacticin Q production in Lactococcus lactis QU 5.

    Science.gov (United States)

    Iwatani, Shun; Ishibashi, Naoki; Flores, Floirendo P; Zendo, Takeshi; Nakayama, Jiro; Sonomoto, Kenji

    2016-09-01

    Lacticin Q is an unmodified leaderless bacteriocin produced by Lactococcus lactis QU 5. It has been revealed that the production and self-immunity of lacticin Q are facilitated by a gene cluster lnqQBCDEF The gene for a putative TetR-family transcriptional regulator, termed lnqR, was found nearby the lnqQBCDEF cluster, but its involvement in lacticin Q biosynthesis remained unknown. In this study, we created an LnqR-overexpressing QU 5 recombinant by using lactococcal constitutive promoter P32 The recombinant QU 5 showed enhanced production of and self-immunity to lacticin Q. RT-PCR analysis has revealed that an overexpression of LnqR increases the amounts of lnqQBCDEF transcripts, and these six genes are transcribed as an operon in a single transcriptional unit. Interestingly, LnqR expression and thus lacticin Q production by L. lactis QU 5 was found temperature dependent, while LnzR, an LnqR-homologue, in L. lactis QU 14 was expressed in a similar but not identical manner to LnqR, resulting in dissimilar bacteriocin productivities by these strains. This report demonstrates LnqR as the first TetR-family transcriptional regulator involved in LAB bacteriocin biosynthesis and that, as an exceptional case of TetR-family regulators, LnqR positively regulates the transcription of these biosynthetic genes. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  20. Gambling related family coping and the impact of problem gambling on families in Hong Kong

    Directory of Open Access Journals (Sweden)

    Elda Mei Lo Chan

    2016-03-01

    Full Text Available Abstract Despite substantial evidence that problem gambling is associated with a wide range of family difficulties, limited effort has been devoted to studying the negative impacts on family members as a result of problem gambling and how they cope and function under the impacts of problem gambling in Chinese communities. Among the very few Chinese-specific gambling-related family impact studies, none have examined how gambling-related family coping responses are related to gambling-related family impacts. Based on a sample of treatment-seeking Chinese family members of problem gamblers, this study aimed to explore: (1 the demographic characteristics and health and psychological well-being of the family members; (2 the gambling-related family member impacts (active disturbance, worrying behavior; (3 the family coping strategies (engaged, tolerant-inactive and withdrawal coping; (4 the relationship between gambling-related family member impacts, psychological distress and family coping strategies. It was hypothesized that positive significant relationships would be found between family member impacts, psychological distress and family coping strategies. From March 2011 to February 2012, a total of 103 family members of problem gamblers who sought help from Tung Wah Group of Hospitals Even Centre in Hong Kong were interviewed. Results showed that a majority of family members were partners or ex-partners of the gambler with low or no income. A large proportion of participants reported moderate to high psychological distress (72.6 %, poor to fair general health (60.2 %, and poor to neither good nor bad quality of life (61.1 %. Family member impacts were positively significantly correlated to all family coping strategies and psychological distress. Tolerant-inactive coping had the strongest relationships with family member impacts and psychological distress. Strong relationships between family member impacts and psychological distress were also

  1. Landau-Ginzburg Limit of Black Hole's Quantum Portrait: Self Similarity and Critical Exponent

    CERN Document Server

    Dvali, Gia

    2012-01-01

    Recently we have suggested that the microscopic quantum description of a black hole is an overpacked self-sustained Bose-condensate of N weakly-interacting soft gravitons, which obeys the rules of 't Hooft's large-N physics. In this note we derive an effective Landau-Ginzburg Lagrangian for the condensate and show that it becomes an exact description in a semi-classical limit that serves as the black hole analog of 't Hooft's planar limit. The role of a weakly-coupled Landau-Ginzburg order parameter is played by N. This description consistently reproduces the known properties of black holes in semi-classical limit. Hawking radiation, as the quantum depletion of the condensate, is described by the slow-roll of the field N. In the semiclassical limit, where black holes of arbitrarily small size are allowed, the equation of depletion is self similar leading to a scaling law for the black hole size with critical exponent 1/3.

  2. Family Ties and Civic Virtues

    DEFF Research Database (Denmark)

    Ljunge, Jan Martin

    I establish a positive relationship between family ties and civic virtues, as captured by disapproval of tax and benefit cheating, corruption, and a range of other dimensions of exploiting others for personal gain. I find that family ties are a complement to social capital, using within country...... evidence from 83 nations and data on second generation immigrants in 29 countries with ancestry in 85 nations. Strong families cultivate universalist values and produce more civic and altruistic individuals. The results provide a constructive role for families in promoting family values that support...

  3. Using Social Network Analysis to Investigate Positive EOL Communication.

    Science.gov (United States)

    Xu, Jiayun; Yang, Rumei; Wilson, Andrew; Reblin, Maija; Clayton, Margaret F; Ellington, Lee

    2018-04-30

    End of life (EOL) communication is a complex process involving the whole family and multiple care providers. Applications of analysis techniques that account for communication beyond the patient and patient/provider, will improve clinical understanding of EOL communication. To introduce the use of social network analysis to EOL communication data, and to provide an example of applying social network analysis to home hospice interactions. We provide a description of social network analysis using social network analysis to model communication patterns during home hospice nursing visits. We describe three social network attributes (i.e. magnitude, directionality, and reciprocity) in the expression of positive emotion among hospice nurses, family caregivers, and hospice cancer patients. Differences in communication structure by primary family caregiver gender and across time were also examined. Magnitude (frequency) in the expression of positive emotion occurred most often between nurses and caregivers or nurses and patients. Female caregivers directed more positive emotion to nurses, and nurses directed more positive emotion to other family caregivers when the primary family caregiver was male. Reciprocity (mutuality) in positive emotion declined towards day of death, but increased on day of actual patient death. There was variation in reciprocity by the type of positive emotion expressed. Our example demonstrates that social network analysis can be used to better understand the process of EOL communication. Social network analysis can be expanded to other areas of EOL research, such as EOL decision-making and health care teamwork. Copyright © 2018. Published by Elsevier Inc.

  4. The Role of Activator Protein-1 (AP-1) Family Members in CD30-Positive Lymphomas

    Science.gov (United States)

    Garces de los Fayos Alonso, Ines; Lagger, Sabine; Merkel, Olaf; Kenner, Lukas

    2018-01-01

    The Activator Protein-1 (AP-1) transcription factor (TF) family, composed of a variety of members including c-JUN, c-FOS and ATF, is involved in mediating many biological processes such as proliferation, differentiation and cell death. Since their discovery, the role of AP-1 TFs in cancer development has been extensively analysed. Multiple in vitro and in vivo studies have highlighted the complexity of these TFs, mainly due to their cell-type specific homo- or hetero-dimerization resulting in diverse transcriptional response profiles. However, as a result of the increasing knowledge of the role of AP-1 TFs in disease, these TFs are being recognized as promising therapeutic targets for various malignancies. In this review, we focus on the impact of deregulated expression of AP-1 TFs in CD30-positive lymphomas including Classical Hodgkin Lymphoma and Anaplastic Large Cell Lymphoma. PMID:29597249

  5. Clarifying Work-Family Intervention Processes: The Roles of Work-Family Conflict and Family Supportive Supervisor Behaviors

    Science.gov (United States)

    Hammer, Leslie B.; Kossek, Ellen E.; Anger, W. Kent; Bodner, Todd; Zimmerman, Kristi L.

    2010-01-01

    Drawing on a conceptual model integrating research on training, work-family interventions, and social support, we conducted a quasi-experimental field study to assess the impact of a supervisory training and self-monitoring intervention designed to increase supervisors' use of family supportive supervisor behaviors. Pre- and post-intervention surveys were completed, nine months apart, by 239 employees at six intervention (N = 117) and six control (N = 122) grocery store sites. Thirty-nine supervisors in the six intervention sites received the training consisting of one hour of self-paced computer-based training, one hour of face-to-face group training, followed by instructions for behavioral self-monitoring (recording the frequency of supportive behaviors) to support on-the-job transfer. Results demonstrated a disordinal interaction for the effect of training and family-to-work conflict on employee job satisfaction, turnover intentions and physical health. In particular, for these outcomes, positive training effects were observed for employees with high family-to-work conflict, while negative training effects were observed for employees with low family-to-work conflict. These moderation effects were mediated by the interactive effect of training and family-to-work conflict on employee perceptions of family-supportive supervisor behaviors. Implications of our findings for future work-family intervention development and evaluation are discussed. PMID:20853943

  6. Intrafamilial clustering of anti-ATLA-positive persons.

    Science.gov (United States)

    Kajiyama, W; Kashiwagi, S; Hayashi, J; Nomura, H; Ikematsu, H; Okochi, K

    1986-11-01

    A total of 1,333 persons in 627 families were surveyed for presence of antibody to adult T-cell leukemia-associated antigen (anti-ATLA). Each person was classified according to the anti-ATLA status (positive for sample 1, negative for sample 2) of the head of household of his or her family. In sample 1, the sex- and age-standardized prevalence of anti-ATLA was 38.5%. This was five times as high as the standardized prevalence in sample 2 (7.8%). There were significant differences in prevalence of anti-ATLA between males in samples 1 and 2 and between females in samples 1 and 2. In every age group, prevalence in sample 1 was greater than that in sample 2 except for males aged 60-69 years. In each of four subareas, families in sample 1 had higher standardized prevalence (29.6-42.5%) than families in sample 2 (6.0-9.7%). Although crude prevalence decreased with family size in sample 1 (62.1-25.4%) as well as in sample 2, indirectly standardized prevalence was almost equal within each sample, regardless of number of family members. The degree of aggregation was independent of locality and family size. These data suggest that anti-ATLA-positive persons aggregate in family units.

  7. Henry Currey FRIBA (1820-1900): leading Victorian hospital architect, and early exponent of the "pavilion principle".

    Science.gov (United States)

    Cook, G C

    2002-06-01

    The "pavilion plan" for hospital design originated in France in the 18th century and was popularised in England by John Roberton and George Godwin in the mid-19th century; the underlying rationale was that with improved ventilation the mortality rate (at that time exceedingly high) was significantly reduced. Among the enthusiasts for this new style was Florence Nightingale (herself a miasmatist)--who had experienced astronomically high death rates in the hospital at Scutari during the Crimean War (1854-6). One of the leading exponents of this style of hospital architecture was Henry Currey (1820-1900) whose greatest achievement was undoubtedly the design for the new St Thomas's Hospital on the Lambeth Palace Road.

  8. Books that Focus on Family.

    Science.gov (United States)

    Winfield, Evelyn T.

    1989-01-01

    Twelve books which touch upon family relationships are reviewed in this article. These books show how families can build positive relationships among their members in a variety of situations. Issues include self-concept, health, sibling rivalry, the generation gap, divorce, and death. (IAH)

  9. Talking about parental substance abuse with children: eight families' experiences of Beardslee's family intervention.

    Science.gov (United States)

    Pihkala, Heljä; Dimova-Bränström, Neda; Sandlund, Mikael

    2017-07-01

    Many children are affected by parental substance use disorder. Beardslee's family intervention (BFI) is a family-based psycho-educative method for children of mentally ill parents, used in psychiatric practise in several Nordic countries. The method has also been used to some extent when a parent suffers from substance use disorder. The aim of the study was to explore the family members' experiences of the BFI when a parent has a diagnosis of substance use disorder, to gain new knowledge about the process of the BFI in this area. Ten children and 14 parents were interviewed about their experiences 6 months after a BFI. The interviews were analyzed by qualitative content analysis. The children's psychological symptoms were measured by the Strengths and Difficulties Questionnaire at baseline and after 6 months. Increased openness about the substance use disorder in the families was a recurrent theme throughout the material and a central issue reported in the children's experiences. The children had a high level of psychological symptoms according to the SDQ at baseline, but the majority of them felt that the BFI made a positive difference in their families and for themselves. The parents reported improved wellbeing of their children. Positive experienced effects for children and parents are reported in families with parental substance use disorder, with possible connection to use of BFI. The present study suggests that Beardslee's family intervention is applicable as a preventive method for children in families with a parent suffering from substance use disorder.

  10. Creating a Social Media Assessment Tool for Family Nursing.

    Science.gov (United States)

    Risling, Tracie; Risling, Derek; Holtslander, Lorraine

    2017-02-01

    The use of social media (SM) is contributing to an unprecedented state of global connectivity and occupying an increasingly prominent position in the lives of individuals and families. The more integrated these media become into society the more likely they are to play a role in overall health and family functioning, be it positively or negatively. Family systems theory provides an ideal lens through which to examine the effects of SM in today's family life. This article introduces a new SM assessment tool aligned with the principles of this foundational theory. Family nurses can use the proposed Social Media Assessment Package (SMAP) to gain an initial picture of usage patterns within a family as well as identify and support positive future SM choices. Practitioners may also use the SMAP in a personal evaluation of their practice as a means to maximize SM use in ongoing professional development.

  11. Associations between family characteristics and parental empowerment in the family, family service situations and the family service system.

    Science.gov (United States)

    Vuorenmaa, M; Perälä, M-L; Halme, N; Kaunonen, M; Åstedt-Kurki, P

    2016-01-01

    Parental empowerment signifies parents' sense of confidence in managing their children, interacting with services that their children use and improving child care services. High empowerment is associated with parents' resilience to demands and their confidence to make decisions and take actions that positively affect their families. Most families with children access various healthcare and education services. Professionals working in these services are therefore ideally placed to reinforce parental empowerment. However, little is known about the characteristics associated with parental empowerment within a generic sample of parents or in the context of basic child care services. The aim of this study was to assess how family characteristics are associated with maternal and paternal empowerment in the family, in service situations and in the service system. Parental empowerment was measured among 955 parents (mothers = 571; fathers = 384) of children aged 0-9 years using the Generic Family Empowerment Scale. Family characteristics were assessed through questions on children, parents and the life situation. Associations between empowerment and family characteristics were evaluated using one-way analysis of variance and t-test. Parental empowerment was predicted by multiple linear regression analysis. Parents' concerns related to their parenting, such as whether they possessed sufficient skills as a parent or losing their temper with children, as well as experiences of stress in everyday life, were negatively associated with all dimensions of maternal and paternal empowerment. Both determinants were more common and more significant in empowerment than child-related problems. Promoting parental self-confidence and providing appropriate emotional and concrete support for everyday functioning may reinforce parental empowerment, thereby enhancing families' well-being and coping, as well as improving their access to required services and timely support. Finally

  12. Exploring Relationships among Proactiveness, Risk-Taking and Innovation Output in Family and Non-Family Firms

    DEFF Research Database (Denmark)

    Craig, Justin B.; Pohjola, Mikko; Kraus, Sascha

    2014-01-01

    In an empirical investigation of 532 Finnish firms, and using the entrepreneurial orientation (EO) literature to frame our arguments, we demonstrate that relationships among proactivity, risk-taking and innovation output differ in family and non-family firms. Specifically, we find evidence...... that risk-taking does not affect innovation output in family firms, whereas in non-family firms, innovation output is increased through risk-taking. Also, proactive family firms influence their innovation output more positively than proactive non-family firms do. This study adds important new insights...... to the growing knowledge of EO, which are discussed in the following for both academic and business audiences....

  13. Daily Stressors and Adult Day Service Use by Family Caregivers: Effects on Depressive Symptoms, Positive Mood and DHEA-S

    Science.gov (United States)

    Zarit, Steven H.; Whetzel, Courtney A.; Kim, Kyungmin; Femia, Elia E.; Almeida, David M.; Rovine, Michael J.; Klein, Laura Cousino

    2014-01-01

    Objectives This study examines effects of daily use of adult day services (ADS) programs by caregivers of individuals with dementia (IWD) on a salivary biomarker of stress reactivity, dehydroepiandrosterone-sulfate (DHEA-S), and whether these effects on DHEA-S are associated with daily variability in positive mood and depressive symptoms. Design We used a daily diary design of 8 consecutive days with alternation of intervention (ADS) and non-intervention days to evaluate within- and between-person effects of the intervention. Setting Caregivers were interviewed daily by telephone at home. Participants 151 family caregivers of IWD who were using ADS. Measurements Saliva samples were collected from caregivers 5 times a day for 8 consecutive days and were assayed for DHEA-S. Daily telephone interviews assessed daily stressors and mood. Results DHEA-S levels were significantly higher on days following ADS use. Daily DHEA-S levels covaried significantly with daily positive mood, but not depressive symptoms. Conclusions These results demonstrate an association of ADS use by family caregivers and higher DHEA-S levels on the next day. Prior research has found that higher DHEA-S levels are protective against the physiological damaging effects of stressor exposure and may reduce risks of illness. Regular use of ADS may help reduce depletion of DHEA-S and allow the body to mount a protective and restorative response to the physiological demands of caregiving. To our knowledge, this is the first study to examine DHEA-S levels across the day in connection with an intervention that affected daily exposure to stressors. PMID:24566240

  14. Daily Positive Spillover and Crossover from Mothers’ Work to Youth Health

    OpenAIRE

    Lawson, Katie M.; Davis, Kelly D.; McHale, Susan M.; Hammer, Leslie B.; Buxton, Orfeu M.

    2014-01-01

    Prior research shows that employees’ work experiences can “spill over” into their family lives and “cross over” to affect family members. Expanding on studies that emphasize negative implications of work for family life, this study examined positive work-to-family spillover and positive and negative crossover between mothers and their children. Participants were 174 mothers in the extended care (nursing home) industry and their children (ages 9-17), both of whom completed daily diaries on the...

  15. Families, Powered On: Improving Family Engagement in Early Childhood Education through Technology. Policy Brief

    Science.gov (United States)

    Daugherty, Lindsay; Dossani, Rafiq; Johnson, Erin-Elizabeth; Wright, Cameron

    2014-01-01

    Family engagement in the education of young children is associated with numerous positive outcomes for those children, and parents and other family members play an important role as "teachers" during the time children spend outside the classroom. Home-based involvement (e.g., a parent-led educational activity), school-based involvement…

  16. The Kerr-Tomimatsu-Sato family of spinning mass solutions

    International Nuclear Information System (INIS)

    Yamazaki, M.

    1982-01-01

    The closed form with an arbitrary positive integer distortion parameter delta of the Kerr-Tomimatsu-Sato family of spinning mass solutions, i.e., stationary axisymmetric, asymptotically flat exact solutions of Einstein's vacuum field equations Rsub(μγ) = 0 is presented. The generalization of the Kerr-Tomimatsu-Sato family of solutions to the case of the arbitrary positive non-integral distortion parameter delta is conjectured. Some analytic properties of the family of solutions are studied. It is shown that all ring singularities are of first order and all ergosurfaces are simple zeros of metric functions f. The charged Kerr-Tomimatsu-Sato family of solutions is also given in the closed form with an arbitrary positive integer distortion parameter delta. It is shown that the Christodoulou-Ruffini mass formula of the Kerr-Newman field or the delta = 1 member of the present family of solutions also holds true in the case of the charged Kerr-Tomimatsu-Sato family of solutions with an arbitary odd integer delta. (Auth.)

  17. Resilient family processes, personal reintegration, and subjective well-being outcomes for military personnel and their family members.

    Science.gov (United States)

    Clark, Malissa A; O'Neal, Catherine W; Conley, Kate M; Mancini, Jay A

    2018-01-01

    Deployment affects not just the service members, but also their family members back home. Accordingly, this study examined how resilient family processes during a deployment (i.e., frequency of communication and household management) were related to the personal reintegration of each family member (i.e., how well each family member begins to "feel like oneself again" after a deployment), as well as several indicators of subjective well-being. Drawing from the family attachment network model (Riggs & Riggs, 2011), the present study collected survey data from 273 service members, their partners, and their adolescent children. Resilient family processes during the deployment itself (i.e., frequency of communication, household management), postdeployment positive and negative personal reintegration, and several indicators of well-being were assessed. Frequency of communication was related to personal reintegration for service members, while household management was related to personal reintegration for nondeployed partners; both factors were related to personal reintegration for adolescents. Negative and positive personal reintegration related to a variety of subjective well-being outcomes for each individual family member. Interindividual (i.e., crossover) effects were also found, particularly between adolescents and nondeployed partners. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  18. Use of family-friendly work arrangements and work-family conflict: Crossover effects in dual-earner couples.

    Science.gov (United States)

    Schooreel, Tess; Verbruggen, Marijke

    2016-01-01

    This study uses a dyadic approach to examine how an employee's work-family conflict is affected when his or her partner makes use of family-friendly work arrangements. We focused on 2 types of family-friendly practices, that is, reduced work hours and schedule or workplace flexibility. Hypotheses were tested with multilevel structural equation modeling using information of 186 dual-earner couples. In line with our hypotheses, we found support for both a positive and a negative crossover effect, though the results showed differences between the 2 types of family-friendly work arrangements. First, a positive crossover effect was found for both reduced work hours and schedule or workplace flexibility; however, the specific mechanisms explaining this effect differed per type of arrangements. In particular, employees whose partner made use of reduced work hours were found to experience less home demands, which was in turn associated with lower family-to-work conflict, whereas employees whose partner made use of schedule or workplace flexibility experienced a similar positive crossover effect but through an increase in the social support they perceived. Second, a negative crossover effect was found only for reduced work hours and not for schedule or workplace flexibility. Specifically, employees whose partner made use of reduced work hours were found to work on average more hours a week, which was in turn related with more work-to-family conflict, whereas employees whose partner made use of schedule or workplace flexibility worked on average fewer hours a week and consequently experienced lower work-to-family conflict. Implications for literature and practice are discussed. (c) 2016 APA, all rights reserved).

  19. Parental stress, family quality of life, and family-teacher partnerships: Families of children with autism spectrum disorder.

    Science.gov (United States)

    Hsiao, Yun-Ju; Higgins, Kyle; Pierce, Tom; Whitby, Peggy J Schaefer; Tandy, Richard D

    2017-11-01

    Reducing parental stress and improving family quality of Life (FQOL) are continuing concerns for families of children with autism spectrum disorder (ASD). Family-teacher partnerships have been identified as a positive factor to help parents reduce their stress and improve their FQOL. However, the interrelations among parental stress, FQOL, and family-teacher partnerships need to be further examined so as to identify the possible paths to help parents reduce their stress and improve their FQOL. The purpose of this study was to examine the interrelations among these three variables. A total of 236 parents of school children with ASD completed questionnaires, which included three measures: (a) the Beach Center Family Quality of Life Scale, (b) the Parental Stress Scale, and (c) the Beach Center Family-Professional Partnerships Scale. The structural equation modeling was used to analyze the interrelations among these three variables. Perceived parental stress had a direct effect on parental satisfaction concerning FQOL and vice versa. Perceived family-teacher partnerships had a direct effect on FQOL, but did not have a direct effect on parental stress. However, family-teacher partnerships had an indirect effect on parental stress through FQOL. Reducing parental stress could improve FQOL for families of children with ASD and vice versa. Strong family-teacher partnerships could help parents of children with ASD improve their FQOL and indirectly reduce their stress. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. A Research Project on Successful Single-Parent Families.

    Science.gov (United States)

    Barry, Ann

    1979-01-01

    Studies variables associated with successful single-parent families. Single parents volunteered to share their positive family experiences. Information was sought on ages of family members and length of single-parent family status, education level and income, relations with absent parent, and relations with children. A hypothesis and counseling…

  1. Adolescent Appraisals of Family Security as a Mediator of the Effect of Family Instability on Adolescent Self-Esteem

    OpenAIRE

    Merkaš, Marina

    2014-01-01

    The aim of this two-wave study was to examine the mediating role of adolescent appraisals of family security in the relation between family instability and adolescent self-esteem in a sample of 377 adolescents and their mothers. Mothers' reports of family instability at Time 1 were significantly and positively associated with adolescent appraisals of family insecurity at Time 1 and Time 2. Adolescent self-esteem at Time 2 was significantly and negatively related to family...

  2. "Connected Presence" in Distributed Family Life

    DEFF Research Database (Denmark)

    Christensen, Toke Haunstrup

    2009-01-01

    also analyses families’ use of the mobile phone in context of modern family life, emphasizing the importance of the temporal and spatial dispersion of family members in explaining the form and content of intra-familial mediated communication. Finally, the dual role of media technologies (including......Concurrently with the recent years’ explosive pervasion of information- and communication technologies, mediated communication has gained a strong position in the daily interaction between family members. Based on the results of qualitative interviews with families in Denmark, this article shows...... the mobile phone) in both integrating and dispersing families is discussed....

  3. The role of family factors in explaining the women’s conflict of work and family roles

    Directory of Open Access Journals (Sweden)

    سیدعلیرضا افشانی

    2016-09-01

    Full Text Available This research aimed to investigate the relationship between family factors including socioeconomic status, family support, family attachment, family role overload, and family power structure with conflict of work and family roles among female employees in Yazd city. Research method was descriptive and correlational; and 323 female employees were selected by cluster sampling method. The work-family roles conflict scales, the perception of social support from family, the family involvement questionnaire, the family roles overload scale, and the scale of power structure in family were used in this study. Data were analyzed by SPSS and AMOS. The Findings indicated that socioeconomic status, family support to employed member, family attachment and family power structure had significant and negative relationship with work and family roles conflict. In contrast there were significant and positive relationships between family role overload with work and family roles conflict. Thus, family factors have a very significant role in amount of work and family roles conflict and also can play an effective role in reducing the conflict-induced pressure and stress.

  4. Electrocortical reactivity to negative and positive facial expressions in individuals with a family history of major depression.

    Science.gov (United States)

    Watters, Anna J; Harris, Anthony W F; Williams, Leanne M

    2018-05-21

    Facial expressions signaling threat and mood-congruent loss have been used to probe abnormal neural reactivity in major depressive disorder (MDD) and may be implicated in genetic vulnerability to MDD. This study investigated electro-cortical reactivity to facial expressions 101 unaffected, adult first degree relatives of probands with MDD and non-relative controls (n = 101). We investigated event-related potentials (ERPs) to five facial expressions of basic emotion: fear, anger, disgust, sadness and happiness under both subliminal (masked) and conscious (unmasked) presentation conditions, and the source localization of group differences. In the conscious condition, controls showed a distinctly positive-going shift in responsive to negative versus happy faces, reflected in a greater positivity for the VPP frontally and the P300 parietally, and less negativity for the N200. By contrast, relatives showed less differentiation of emotions, reflected in less VPP and P300 positivity, particularly for anger and disgust, and which produced an enhanced N200 for sadness. These group differences were consistently source localized to the anterior cingulate cortex. The findings contribute new evidence for neural disruptions underlying the differentiation of salient emotions in familial risk for depression. These disruptions occur in the appraisal (∼200 ms post-stimulus) through to the context evaluation (∼300 ms+ post-stimulus) phases of of emotion processing, consistent with theories that risk for depression involves biased or attenuated processing of emotion. Copyright © 2018. Published by Elsevier B.V.

  5. Familial associations between polycystic ovarian syndrome and common diseases.

    Science.gov (United States)

    Moini, Ashraf; Eslami, Bita

    2009-03-01

    The goal of this study was focused on two subjects. First, to determine possible association between PCOS and family history of breast cancer, ovarian cancer, endometrial cancer, heart attack, thrombosis, diabetes and cardiovascular disease (CVD). Second, to evaluate maternal and paternal transmission in PCOS patients with positive family history of a disease. A cross-sectional study was conducted in 549 infertile women (273 with PCOS and 276 controls) in Arash hospital of Tehran, Iran, between 2007 and 2008 by using questionnaire. In this analysis, there were significantly increased number of women with the positive family history of diabetes among PCOS group (28.21% vs. 19.20%, p=0.01). Meanwhile, four women in PCOS group had self history of diabetes while no one in the control group reported diabetes. A statistically significant positive family history of breast cancer was found among the control group (4.35% vs. 1.30%, p=0.02). Endometrial cancer and diabetes were observed in mother or mother's side of the family but heart attack and thrombosis manifested in father or father's side of the family more. There were no statistically significant differences in a positive individual or family history of ovarian cancer, endometrial cancer, heart attack, thrombosis and CVD between the two groups. In the present study, women and their relatives with PCOS had an increased prevalence of diabetes and it is more common in mother's side of the family.

  6. Strengthening family coping resources: the feasibility of a multifamily group intervention for families exposed to trauma.

    Science.gov (United States)

    Kiser, Laurel J; Donohue, April; Hodgkinson, Stacy; Medoff, Deborah; Black, Maureen M

    2010-12-01

    Families exposed to urban poverty face a disproportionate risk of exposure to repeated trauma. Repeated exposures can lead to severe and chronic reactions in multiple family members with effects that ripple throughout the family system. Interventions for distressed families residing in traumatic contexts, such as low-income, urban settings are desperately needed. This report presents preliminary data in support of Strengthening Family Coping Resources, a trauma-focused, multifamily, skill-building intervention. Strengthening Family Coping Resources is designed for families living in traumatic contexts with the goal of reducing symptoms of posttraumatic stress disorder and other trauma-related disorders in children and caregivers. Results from open trials suggest Strengthening Family Coping Resources is a feasible intervention with positive effects on children's symptoms of trauma-related distress.

  7. Influence of finite-time Lyapunov exponents on winter precipitation over the Iberian Peninsula

    Science.gov (United States)

    Garaboa-Paz, Daniel; Lorenzo, Nieves; Pérez-Muñuzuri, Vicente

    2017-05-01

    Seasonal forecasts have improved during the last decades, mostly due to an increase in understanding of the coupled ocean-atmosphere dynamics, and the development of models able to predict the atmosphere variability. Correlations between different teleconnection patterns and severe weather in different parts of the world are constantly evolving and changing. This paper evaluates the connection between winter precipitation over the Iberian Peninsula and the large-scale tropospheric mixing over the eastern Atlantic Ocean. Finite-time Lyapunov exponents (FTLEs) have been calculated from 1979 to 2008 to evaluate this mixing. Our study suggests that significant negative correlations exist between summer FTLE anomalies and winter precipitation over Portugal and Spain. To understand the mechanisms behind this correlation, summer anomalies of the FTLE have also been correlated with other climatic variables such as the sea surface temperature (SST), the sea level pressure (SLP) or the geopotential. The East Atlantic (EA) teleconnection index correlates with the summer FTLE anomalies, confirming their role as a seasonal predictor for winter precipitation over the Iberian Peninsula.

  8. Family Care Map: Sustaining family-centered care in Polytrauma Rehabilitation Centers

    Science.gov (United States)

    Ford, James H.; Wise, Meg; Krahn, Dean; Oliver, Karen Anderson; Hall, Carmen; Sayer, Nina

    2015-01-01

    The study assessed sustainability of the Family Care Map, a family-centered approach to providing care for Veterans with polytrauma-related injuries, in four Department of Veterans Affairs Polytrauma Rehabilitation Centers. We applied a mixed-methods approach. Staff surveys used standardized measures of sustainability, commitment to change, information, and participation during implementation. Qualitative inquiry assessed Family Care Map implementation and facilitators and barriers to sustainability. Staff sustainability perceptions had a significant positive correlation with affective commitment to change, participation, and information received about the change process. Family Care Map integration into standard practices and use of its concepts with patients and families related to staff perceptions about sustainability. The degree of use and integration of the Family Care Map in traumatic brain injury/polytrauma care varied among the Polytrauma Rehabilitation Centers. Some successful sustainability strategies included integration into daily workflow and organizational culture. Examples of sustainability barriers included staff awareness and use and outdated information. Some practices, such as measuring and documenting the use of the Family Care Map in treatment plans, may not routinely occur. The focus on family-centered care will require further evaluation of organization-, staff-, and innovation-level attributes that influence sustainability of changes designed to improve family-centered care. PMID:25671632

  9. Beyond the Young-Laplace model for cluster growth during dewetting of thin films: effective coarsening exponents and the role of long range dewetting interactions.

    Science.gov (United States)

    Constantinescu, Adi; Golubović, Leonardo; Levandovsky, Artem

    2013-09-01

    Long range dewetting forces acting across thin films, such as the fundamental van der Waals interactions, may drive the formation of large clusters (tall multilayer islands) and pits, observed in thin films of diverse materials such as polymers, liquid crystals, and metals. In this study we further develop the methodology of the nonequilibrium statistical mechanics of thin films coarsening within continuum interface dynamics model incorporating long range dewetting interactions. The theoretical test bench model considered here is a generalization of the classical Mullins model for the dynamics of solid film surfaces. By analytic arguments and simulations of the model, we study the coarsening growth laws of clusters formed in thin films due to the dewetting interactions. The ultimate cluster growth scaling laws at long times are strongly universal: Short and long range dewetting interactions yield the same coarsening exponents. However, long range dewetting interactions, such as the van der Waals forces, introduce a distinct long lasting early time scaling behavior characterized by a slow growth of the cluster height/lateral size aspect ratio (i.e., a time-dependent Young angle) and by effective coarsening exponents that depend on cluster size. In this study, we develop a theory capable of analytically calculating these effective size-dependent coarsening exponents characterizing the cluster growth in the early time regime. Such a pronounced early time scaling behavior has been indeed seen in experiments; however, its physical origin has remained elusive to this date. Our theory attributes these observed phenomena to ubiquitous long range dewetting interactions acting across thin solid and liquid films. Our results are also applicable to cluster growth in initially very thin fluid films, formed by depositing a few monolayers or by a submonolayer deposition. Under this condition, the dominant coarsening mechanism is diffusive intercluster mass transport while the

  10. Work and Family Balance Among Icelandic Employees with Young Children

    DEFF Research Database (Denmark)

    Arnardottir, Audur Arna; Hreinsson, Sturla; Sigurjonsson, Olaf

    Work-family balance is one of the major organizational challenges of the 21st century. Extensive research has been conducted that assesses wf-balance from the conflict standpoint, but in recent years, benefits, resulting from simultaneous participation in the work and family role, have gained......, and mothers experienced significantly more enrichment then men. Work-family enrichment and family-work enrichment were positively correlated to job satisfaction, emotional organizational commitment, life and family satisfaction (r=.25 to.45), whereas work-family conflict and family-work conflict were...... increased interest. This research literature is much less developed and scholars have called for more international studies that simultaneously look at the positive and negative sides of the work-family interface. This study answers to that call and assesses work and family conflict and enrichment from...

  11. Family meals with young children: an online study of family mealtime characteristics, among Australian families with children aged six months to six years.

    Science.gov (United States)

    Litterbach, Eloise-Kate V; Campbell, Karen J; Spence, Alison C

    2017-01-24

    Evidence suggests that family meals influence food intakes and behaviours, which in turn impact children's eating habits, diets and health. Mealtimes therefore offer potential as settings for health promotion. Given diet, health behaviours and health are often socioeconomically patterned, it is important to consider whether family meals differ by socioeconomic position (SEP). The Family Meals with Young Kids study was an online survey completed by parents in 2014. Mealtime characteristics measured included; frequency of shared meals across the day, duration and location of mealtimes, parental modelling, and parental perceived importance of the evening meal. Maternal education was used to assess SEP. The aims of this study were to describe family meal characteristics among Australian families with children aged six months to six years and to describe the socioeconomic patterning of these. Participants (n = 992) were mostly mothers (97%) with a university degree (71%). The evening meal was the most frequently reported meal eaten together with the responding parent and child (77% ≥ five nights/week). Snacks were least commonly eaten together (39% ≥ five days/week). The frequency of having everyone present for the evening meal was inversely associated with SEP (OR 0.70, CI 0.54-0.92). Parent rated importance of family meals was generally high and positively associated with higher SEP (OR 1.32, CI 1.00-1.76). Most children consumed breakfast (73%), lunch (58%) and dinner (82%) sitting at a table or bench and this was positively associated with higher SEP for all meal types (OR 1.61-2.37, p meals was inversely associated with SEP (OR 0.63, CI 0.54-0.72). Less than half of children (36%) watched TV during meals more than once a day. Australian families engage in many healthy mealtime behaviours. Evidence that parents share meals with children and place high value on mealtimes with children provides important opportunities for promoting healthy behaviours

  12. QUAD FAMILY CENTERING

    International Nuclear Information System (INIS)

    PINAYEV, I.

    2005-01-01

    It is well known that beam position monitors (BPM) utilizing signals from pickup electrodes (PUE) provide good resolution and relative accuracy. The absolute accuracy (i.e. position of the orbit in the vacuum chamber) is not very good due to the various reasons. To overcome the limitation it was suggested to use magnetic centers of quadrupoles for the calibration of the BPM [1]. The proposed method provides accuracy better then 200 microns for centering of the beam position monitors using modulation of the whole quadrupole family

  13. INSTITUTIONALIZATION OF FAMILY FARMING IN THE CONTEXT OF A FAMILY BUSINESS IN UKRAINE

    Directory of Open Access Journals (Sweden)

    Y. Solonenko

    2016-03-01

    Full Text Available This article explores the situation of family farms in the world, highlighted their key role in ensuring food security and preserving natural resources. We consider the activities of the Food and Agriculture Organization (FAO of the United Nations aimed at supporting and developing family farms at the regional, national, international levels. In the process of reforming the agricultural sector of Ukraine is the search for effective forms and methods of management. By introducing international experience progressive institutional approach to a market economy in agricultural production, the country embarked on the creation of family farms. Family farms is the most effective form of economic activity in rural areas, provided their institutionalization, state support, fight against corruption and monopolies in agribusiness. In the article the formation of family farms in Ukraine from institutional positions. Reflects the process of formation of the Institute for Family Business in Ukraine as family farms. Defined intrinsic characteristics and stages of institutionalization of family farms. The analysis measures the state and society on the institutionalization of family farms in Ukraine. Outlined prospects of Ukrainian family farms and proposed institutional arrangements to ensure the balanced functioning of a viable model of family farm management in the context of the family business in Ukraine.

  14. A revision of the family Taccaceae

    NARCIS (Netherlands)

    Drenth, E.

    1972-01-01

    A historical survey of the family is followed by a discussion of the systematic position, the affinities within the family, the morphology, anatomy, phytochemical characters, flower biology, geographical distribution, dispersal, and growth. A key to the species is given. Each taxon has been

  15. Altered parenting and the reconstituted family.

    Science.gov (United States)

    Whitley, G G; Kachel, J M

    1991-01-01

    Reconstituted families are a high incidence phenomena in contemporary society. Because the family continues to be a focus for the delivery of nursing care, nurses must now address the special needs of individuals who are members of reconstituted families. Studies in this area provide important background information regarding behavioral patterns in reconstituted families that can be used for assessment and intervention with these families. Through the use of focused assessment parameters, nurses can collect data that will indicate the special needs of members of reconstituted families. In general, nursing interventions with clients who are a part of a reconstituted family fall into two major categories: (a) developing positive parenting behaviors, and (b) protecting the development of the stepchild.

  16. A discrete model on Sierpinski gasket substrate for a conserved current equation with a conservative noise

    Science.gov (United States)

    Kim, Dae Ho; Kim, Jin Min

    2012-09-01

    A conserved discrete model on the Sierpinski gasket substrate is studied. The interface width W in the model follows the Family-Vicsek dynamic scaling form with growth exponent β ≈ 0.0542, roughness exponent α ≈ 0.240 and dynamic exponent z ≈ 4.42. They satisfy a scaling relation α + z = 2zrw, where zrw is the random walk exponent of the fractal substrate. Also, they are in a good agreement with the predicted values of a fractional Langevin equation \\frac{\\partial h}{\\partial t}={\

  17. Empowering the family for girl child development.

    Science.gov (United States)

    Desai, M

    1995-01-01

    This article discusses family interactions that devalue female children in India and the role of government in enriching family life. Child development is dependent upon the family and the social environment. Patriarchy establishes the structure, roles, and responsibilities of the family through hierarchies of age, gender, and generation. Males hold authoritative positions because of their control over resources and the assumption of their superiority. Family unity and stability is based on conformity with the community and kinship norms. The Indian family places a low priority on the development of individual family members and children. Female children are a low priority both as children and as girls. Girls carry a heavy domestic workload in the family, but girls do not receive recognition for their contributions. The family socializes children based on norms of gender and age inequalities. Deviation from patriarchal norms results in ostracism. Families without resources are vulnerable to deprivation and exploitation. Gaps have widened between rich and poor, and men and women. Particularly vulnerable groups are women in single-parent families and female-headed households. The combination of patriarchy, increased consumerism, and structural adjustment programs marginalizes girl children. Every family should be considered equal in dignity and worth and have the right to freedom, choices, life, security of person and privacy, and protection from domestic violence. Vulnerable family members need special attention. Every family member should take responsibility for promoting sensitivity and responsiveness, positive communication, companionable relationships, democratic decision making, respect for individual needs and differences, peaceful and nonviolent approaches for resolving conflicts, and support in crisis situations.

  18. Work-to-Family Conflict, Positive Spillover, and Boundary Management: A Person-Environment Fit Approach

    Science.gov (United States)

    Chen, Zheng; Powell, Gary N.; Greenhaus, Jeffrey H.

    2009-01-01

    This study adopted a person-environment fit approach to examine whether greater congruence between employees' preferences for segmenting their work domain from their family domain (i.e., keeping work matters at work) and what their employers' work environment allowed would be associated with lower work-to-family conflict and higher work-to-family…

  19. Attachment and Family Processes in Children's Psychological Adjustment in Middle Childhood.

    Science.gov (United States)

    Demby, Kimberly P; Riggs, Shelley A; Kaminski, Patricia L

    2017-03-01

    This study examined the links between parent-child attachment, whole family interaction patterns, and child emotional adjustment and adaptability in a sample of 86 community families with children between the ages of 8 and 11 years. Family interactions were observed and coded with the System for Coding Interactions and Family Functioning (SCIFF; Lindahl, 2001). Both parents and each target child completed the appropriate form of the Behavior Assessment System for Children-2nd Edition (BASC-2; Reynolds & Kamphaus, 2004). Target children also completed the Children's Coping Strategies Questionnaire (CCSQ; Yunger, Corby, & Perry, 2005). Hierarchical multiple regressions indicated that Secure mother-child attachment was a robust predictor of children's emotional symptoms, but father-child attachment strategies were not significant independent predictors. Positive Affect in family interactions significantly increased the amount of variance accounted for in children's emotional symptoms. In addition, Family Cohesion and Positive Affect moderated the relationship between father-child attachment and children's emotional symptoms. When data from all BASC-2 informants (mother, father, child) were considered simultaneously and multidimensional constructs were modeled, mother-child security directly predicted children's adjustment and adaptive skills, but the influence of father-child security was fully mediated through positive family functioning. Results of the current study support the utility of considering dyadic attachment and family interaction patterns conjointly when conceptualizing and fostering positive emotional and behavioral outcomes in children. © 2015 Family Process Institute.

  20. IDEA and Family Involvement

    Directory of Open Access Journals (Sweden)

    Mehmet Emin Öztürk

    2017-01-01

    Full Text Available Individuals with Disabilities Education Act (IDEA gives many rights to parents with special needs in terms of involvement and participation. Given the importance of family involvement in the special education process, and federal legislation that increasingly mandated and supported such involvement over time, considerable research has focused on the multiple ways that relationships between schools and families in the special education decision making process have played out. Educational professionals should create a positive climate for CLD families so that they feel more comfortable and therefore are able to participate more authentically and meaningfully.