WorldWideScience

Sample records for positive exponent family

  1. 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…

  2. 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

  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. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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

  11. 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

  12. 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...

  13. 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 ...

  14. 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.,…

  15. 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.

  16. 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…

  17. 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...

  18. 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...

  19. 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,…

  20. 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.

  1. 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.

  2. 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

  3. 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)

  4. 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.

  5. 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)

  6. 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.

  7. 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

  8. 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

  9. 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.

  10. 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.

  11. 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.

  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. 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

  14. 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...

  15. 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…

  16. 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

  17. 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)

  18. 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...

  19. 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.

  20. 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

  1. 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,…

  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. 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.)

  4. 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.

  5. 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.

  6. Positive Behavior Support and Applied Behavior Analysis: A Familial Alliance

    Science.gov (United States)

    Dunlap, Glen; Carr, Edward G.; Horner, Robert H.; Zarcone, Jennifer R.; Schwartz, Ilene

    2008-01-01

    Positive behavior support (PBS) emerged in the mid-1980s as an approach for understanding and addressing problem behaviors. PBS was derived primarily from applied behavior analysis (ABA). Over time, however, PBS research and practice has incorporated evaluative methods, assessment and intervention procedures, and conceptual perspectives associated…

  7. [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.

  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. 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.

  10. 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.

  11. 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.

  12. 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

  13. 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…

  14. [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.

  15. 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

  16. 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.

  17. 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...

  18. 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.

  19. 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)

  20. 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

  1. 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

  2. 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.

  3. 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.

  4. 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

  5. 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.

  6. 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

  7. 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...

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. 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…

  14. 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.

  15. 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.

  16. 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…

  17. 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,…

  18. 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…

  19. 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,…

  20. 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 ...

  1. 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

  2. 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.

  3. 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.

  4. 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

  5. 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.

  6. 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.

  7. 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.

  8. 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...

  9. 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.

  10. 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

  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. 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

  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. 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.

  15. 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.

  16. 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

  17. 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

  18. 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

  19. 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.

  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. 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

  2. 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

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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

  12. 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.

  13. 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…

  14. 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…

  15. 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.

  16. 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)

  17. 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.

  18. 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

  19. 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.

  20. 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.

  1. 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

  2. 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

  3. 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)

  4. 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 ).

  5. 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

  6. 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...

  7. 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…

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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 ...

  15. 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).

  16. 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

  17. 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...

  18. 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.

  19. 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...

  20. 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)

  1. 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.

  2. 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.

  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. 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)

  5. 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.

  6. 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…

  7. 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 ...

  8. 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.

  9. 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.

  10. Marriage, Family and Gender Inequality : An historical exploration of the relationship between family systems, the position of women and development

    NARCIS (Netherlands)

    Carmichael, S.G.|info:eu-repo/dai/nl/35751405X

    2016-01-01

    This dissertation explores the historical underpinnings of current day gender inequalities at a global scale, with a focus on female agency (the degree of control people have over their own lives). To do so it brings together different explorations of the position of women both historically and

  11. 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…

  12. 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...

  13. 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.

  14. 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…

  15. 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…

  16. 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 ...

  17. 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

  18. 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.

  19. 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].

  20. 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.

  1. 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)

  2. 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.

  3. Cortical thickness and VBM in young women at risk for familial depression and their depressed mothers with positive family history.

    Science.gov (United States)

    Ozalay, Ozgun; Aksoy, Burcu; Tunay, Sebnem; Simsek, Fatma; Chandhoki, Swati; Kitis, Omer; Eker, Cagdas; Gonul, Ali Saffet

    2016-06-30

    It has been demonstrated that compared to low-risk subjects, high-risk subjects for depression have structural and functional alterations in their brain scans even before the disease onset. However, it is not known if these alterations are related to vulnerability to depression or epiphenomena. One way to resolve this ambiguity is to detect the structural alterations in the high-risk subjects and determine if the same alterations are present in the probands. In this study, we recruited 24 women with the diagnosis of Major Depressive Disorder (MDD) with recurrent episodes and their healthy daughters (the high-risk for familial depression group; HRFD). We compared structural brain scans of the patients and HRFG group with those of 24 age-matched healthy mothers and their healthy daughters at similar ages to the HRFD group; respectively. Both cortical gray matter (GM) volume and thickness analyses revealed that HRFD daughters and their MDD mothers had similar GM differences in two regions: the right temporoparietal region and the dorsomedial prefrontal cortex. These results suggested that the observed alterations may be related to trait clinical and neurophysiological characteristics of MDD and may present before the onset of illness. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  4. 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...

  5. 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.

  6. 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

  7. 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...

  8. 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.)

  9. 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.

  10. 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.

  11. 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

  12. 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.

  13. 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.

  14. 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.

  15. 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

  16. Using Pediatric Visits to Support Children and Families: Ten Positive Outcomes From HealthySteps

    Science.gov (United States)

    MacLaughlin, Sarah; Gillespie, Linda; Parlakian, Rebecca

    2017-01-01

    Pediatric health care practices are ideal settings within which to provide vital screenings, support, and parent education to families of infants and toddlers. HealthySteps (HS) uses an integrated, relationship-based approach to deliver a range of services and supports such as anticipatory guidance, developmental and behavioral screenings,…

  17. Multigenerational Positive Family History of Psychiatric Disorders Is Associated With a Poor Prognosis in Bipolar Disorder

    NARCIS (Netherlands)

    Post, Robert M.; Altshuler, Lori; Kupka, Ralph; McElroy, Susan L.; Frye, Mark A.; Rowe, Michael; Grunze, Heinz; Suppes, Trisha; Keck, Paul E.; Leverich, Gabriele S.; Nolen, Willem A.

    2015-01-01

    The authors assessed how family history loading affected the course of illness in patients from the United States. A total of 676 outpatients with bipolar disorder from the United States rated their illness and provided a parental and grandparental history of mood disorder, substance abuse, and

  18. 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

  19. 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

  20. 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

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  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

    2017-01-01

    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

  9. 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.

  10. 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.

  11. 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.

  12. 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

  13. Positive selection in the SLC11A1 gene in the family Equidae

    DEFF Research Database (Denmark)

    Bayerova, Zuzana; Janova, Eva; Matiasovic, Jan

    2016-01-01

    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...

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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

  3. 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

  4. 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.

  5. 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.

  6. 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...

  7. 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.

  8. 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.

  9. 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)

  10. 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…

  11. 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…

  12. 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.

  13. Identification of Phylogenetic Position in the Chlamydiaceae Family for Chlamydia Strains Released from Monkeys and Humans with Chlamydial Pathology

    Directory of Open Access Journals (Sweden)

    Alexander Karaulov

    2010-01-01

    Full Text Available Based on the results of the comparative analysis concerning relatedness and evolutional difference of the 16S–23S nucleotide sequences of the middle ribosomal cluster and 23S rRNA I domain, and based on identification of phylogenetic position for Chlamydophila pneumoniae and Chlamydia trichomatis strains released from monkeys, relatedness of the above stated isolates with similar strains released from humans and with strains having nucleotide sequences presented in the GenBank electronic database has been detected for the first time ever. Position of these isolates in the Chlamydiaceae family phylogenetic tree has been identified. The evolutional position of the investigated original Chlamydia and Chlamydophila strains close to analogous strains from the Gen-Bank electronic database has been demonstrated. Differences in the 16S–23S nucleotide sequence of the middle ribosomal cluster and 23S rRNA I domain of plasmid and nonplasmid Chlamydia trachomatis strains released from humans and monkeys relative to different genotype groups (group B-B, Ba, D, Da, E, L1, L2, L2a; intermediate group-F, G, Ga have been revealed for the first time ever. Abnormality in incA chromosomal gene expression resulting in Chlamydia life development cycle disorder, and decrease of Chlamydia virulence can be related to probable changes in the nucleotide sequence of the gene under consideration

  14. Unintended pregnancy among HIV positive couples receiving integrated HIV counseling, testing, and family planning services in Zambia.

    Science.gov (United States)

    Wall, Kristin M; Haddad, Lisa; Vwalika, Bellington; Htee Khu, Naw; Brill, Ilene; Kilembe, William; Stephenson, Rob; Chomba, Elwyn; Vwalika, Cheswa; Tichacek, Amanda; Allen, Susan

    2013-01-01

    We describe rates of unintended pregnancy among HIV positive couples in Lusaka, Zambia. We also identify factors associated with unintended pregnancy among oral contraceptive pill (OCP) using couples in this cohort. Data were analyzed from couples randomized in a factorial design to two family planning intervention videos. Rates of unintended pregnancy were stratified by contraceptive method used at time of pregnancy. Predictors of time to unintended pregnancy among OCP users were determined via multivariate Cox modeling. The highest rates of unintended pregnancy were observed among couples requesting condoms only (26.4/100CY) or OCPs (20.7/100CY); these rates were not significantly different. OCP users accounted for 37% of the couple-years (CY) observed and 87% of unintended pregnancies. Rates of unintended pregnancy for injectable (0.7/100CY) and intrauterine device (1.6/100CY) users were significantly lower relative to condom only users. No pregnancies occurred among contraceptive implant users or after tubal ligation. Factors associated (psex without a condom. Long-acting reversible contraceptive methods were effective in the context of integrated couples HIV prevention and contraceptive services. Injectable methods were also effective in this context. Given the high user failure rate of OCPs, family planning efforts should promote longer-acting methods among OCP users wishing to avoid pregnancy. Where other methods are not available or acceptable, OCP adherence counseling is needed, especially among younger and new OCP users. ClinicalTrials.gov NCT00067522.

  15. 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

  16. 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)

  17. Agp2, a Member of the Yeast Amino Acid Permease Family, Positively Regulates Polyamine Transport at the Transcriptional Level

    KAUST Repository

    Aouida, Mustapha

    2013-06-03

    Agp2 is a plasma membrane protein of the Saccharomyces cerevisiae amino acid transporter family, involved in high-affinity uptake of various substrates including L-carnitine and polyamines. The discovery of two high affinity polyamine permeases, Dur3 and Sam3, prompted us to investigate whether Agp2 directly transports polyamines or acts instead as a regulator. Herein, we show that neither dur3? nor sam3? single mutant is defective in polyamine transport, while the dur3? sam3? double mutant exhibits a sharp decrease in polyamine uptake and an increased resistance to polyamine toxicity similar to the agp2? mutant. Studies of Agp2 localization indicate that in the double mutant dur3? sam3?, Agp2-GFP remains plasma membrane-localized, even though transport of polyamines is strongly reduced. We further demonstrate that Agp2 controls the expression of several transporter genes including DUR3 and SAM3, the carnitine transporter HNM1 and several hexose, nucleoside and vitamin permease genes, in addition to SKY1 encoding a SR kinase that positively regulates low-affinity polyamine uptake. Furthermore, gene expression analysis clearly suggests that Agp2 is a strong positive regulator of additional biological processes. Collectively, our data suggest that Agp2 might respond to environmental cues and thus regulate the expression of several genes including those involved in polyamine transport. © 2013 Aouida et al.

  18. Agp2, a Member of the Yeast Amino Acid Permease Family, Positively Regulates Polyamine Transport at the Transcriptional Level

    KAUST Repository

    Aouida, Mustapha; Texeira, Marta Rubio; Thevelein, Johan M.; Poulin, Richard; Ramotar, Dindial

    2013-01-01

    Agp2 is a plasma membrane protein of the Saccharomyces cerevisiae amino acid transporter family, involved in high-affinity uptake of various substrates including L-carnitine and polyamines. The discovery of two high affinity polyamine permeases, Dur3 and Sam3, prompted us to investigate whether Agp2 directly transports polyamines or acts instead as a regulator. Herein, we show that neither dur3? nor sam3? single mutant is defective in polyamine transport, while the dur3? sam3? double mutant exhibits a sharp decrease in polyamine uptake and an increased resistance to polyamine toxicity similar to the agp2? mutant. Studies of Agp2 localization indicate that in the double mutant dur3? sam3?, Agp2-GFP remains plasma membrane-localized, even though transport of polyamines is strongly reduced. We further demonstrate that Agp2 controls the expression of several transporter genes including DUR3 and SAM3, the carnitine transporter HNM1 and several hexose, nucleoside and vitamin permease genes, in addition to SKY1 encoding a SR kinase that positively regulates low-affinity polyamine uptake. Furthermore, gene expression analysis clearly suggests that Agp2 is a strong positive regulator of additional biological processes. Collectively, our data suggest that Agp2 might respond to environmental cues and thus regulate the expression of several genes including those involved in polyamine transport. © 2013 Aouida et al.

  19. 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.

  20. 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

  1. 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…

  2. 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.

  3. 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...

  4. Fermentation of glycolate by a pure culture of a strictly anaerobic gram-positive bacterium belonging to the family Lachnospiraceae.

    Science.gov (United States)

    Janssen, Peter H; Hugenholtz, Philip

    2003-05-01

    The component bacteria of a three-membered mixed culture able to ferment glycolate to acetate, propionate and CO(2) were isolated in pure culture. All three strains were strict anaerobes that, on the basis of comparative 16S rRNA gene sequence analysis, belonged to the order Clostridiales in the phylum Firmicutes (low G+C gram-positive bacteria). Two of the strains were not involved in glycolate metabolism. The third, the glycolate-fermenting strain 19gly4 (DSM 11261), was related to members of the family Lachnospiraceae. The cells of strain 19gly4 were oval- to lemon-shaped, 0.85 microm long and 0.65 microm in diameter, occurring singly, in pairs, or in chains of up to 30 cells. Strain 19gly4 fermented glycolate or fumarate to acetate, succinate, and CO(2). Hydrogen was not formed, and strain 19gly4 was able to grow on glycolate in pure culture without any syntrophic hydrogen transfer and without the use of an external electron acceptor. There was no evidence for homoacetogenic metabolism. This bacterium therefore differs in metabolism from previously reported glycolate-utilising anaerobes.

  5. 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.

  6. 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

  7. 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

  8. 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

  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. 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.

  11. Support of positive association in family-based genetic analysis between COL27A1 and Tourette syndrome.

    Science.gov (United States)

    Liu, Shiguo; Yu, Xiaoxia; Xu, Quanchen; Cui, Jiajia; Yi, Mingji; Zhang, Xinhua; Ge, Yinlin; Ma, Xu

    2015-08-03

    Recently, a genome-wide association study has indicated associations between single nucleotide polymorphisms in the Collagen Type XXVII Alpha 1 gene (COL27A1) and Tourette syndrome in several ethnic populations. To clarify the global relevance of the previously identified SNPs in the development of Tourette syndrome, the associations between polymorphisms in COL27A1 and Tourette syndrome were assessed in Chinese trios. PCR-directed sequencing was used to evaluate the genetic contributions of three SNPs in COL27A1(rs4979356, rs4979357 and rs7868992) using haplotype relative risk (HRR) and transmission disequilibrium tests (TDT) with a total of 260 Tourette syndrome trios. The family-based association was significant between Tourette syndrome and rs4979356 (TDT: χ2 = 4.804, P = 0.033; HRR = 1.75, P = 0.002; HHRR = 1.32, P = 0.027), and transmission disequilibrium was suspected for rs4979357 (TDT: χ2 = 3.969, P = 0.053; HRR = 1.84, P = 0.001; HHRR = 1.29, P = 0.044). No statistically significant allele transfer was found for rs7868992 (TDT: χ2 = 2.177, P = 0.158). Although the TDT results did not remain significant after applying the conservative Bonferroni correction (p = 0.005), the significant positive HRR analysis confirmed the possibility of showing transmission disequilibrium, which provides evidence for an involvement of COL27A1in the development of TS. However, these results need to be verified with larger datasets from different populations.

  12. Does It Matter if Preschool Children and Mothers Discuss Positive vs. Negative Events during Reminiscing? Links with Mother-Reported Attachment, Family Emotional Climate, and Socioemotional Development

    Science.gov (United States)

    Laible, Deborah

    2011-01-01

    The purpose of the study was to examine the differential relations between mother-child reminiscing about a positive emotional event vs. a negative emotional event and attachment security, family climate, and young children's socioemotional development. Fifty preschool children (M age = 50.69 months, SD = 4.64) and their mothers completed two…

  13. 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,

  14. 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

  15. 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.

  16. Messages on pregnancy and family planning that providers give women living with HIV in the context of a Positive Health, Dignity, and Prevention intervention in Mozambique

    Directory of Open Access Journals (Sweden)

    Hilliard S

    2014-12-01

    Full Text Available Starr Hilliard, Sarah A Gutin, Carol Dawson Rose Department of Community Health Systems, School of Nursing, University of California at San Francisco, San Francisco, CA, USA Background: Family planning is an important HIV prevention tool for women living with HIV (WLHIV. In Mozambique, the prevalence of HIV among women of reproductive age is 13.1% and the average fertility rate is high. However, family planning and reproductive health for WLHIV are under-addressed in Mozambique. This study explores provider descriptions of reproductive health messages in order to identify possible barriers and facilitators to successfully addressing family planning and pregnancy concerns of WLHIV. Methods: In 2006, a Positive Health, Dignity, and Prevention program was introduced in Mozambique focused on training health care providers to work with patients to reduce their transmission risks. Providers received training on multiple components, including family planning and prevention of mother-to-child transmission (PMTCT. In-depth interviews were conducted with 31 providers who participated in the training in five rural clinics in three provinces. Data were analyzed using qualitative content analysis. Results: Analysis showed that providers' clinical messages on family planning, pregnancy, and PMTCT for WLHIV could be arranged along a continuum. Provider statements ranged from saying that WLHIV should not become pregnant and condoms are the only valid form of family planning for WLHIV, to suggesting that WLHIV can have safe pregnancies. Conclusion: These data indicate that many providers continue to believe that WLHIV should not have children and this represents a challenge for integrating family planning into the care of WLHIV. Also, not offering WLHIV a full selection of family planning methods severely limits their ability to protect themselves from unintended pregnancies and to fully exercise their reproductive rights. Responding to the reproductive health

  17. 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

  18. 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

  19. 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

  20. 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.

  1. 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

  2. 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.

  3. 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.

  4. 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

  5. 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.

  6. 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)

  7. Mental Models of Cause and Inheritance for Type 2 Diabetes Among Unaffected Individuals Who Have a Positive Family History.

    Science.gov (United States)

    Daack-Hirsch, Sandra; Shah, Lisa L; Cady, Alyssa D

    2018-03-01

    Using the familial risk perception (FRP) model as a framework, we elicited causal and inheritance explanations for type 2 diabetes (T2D) from people who do not have T2D but have a family history for it. We identified four composite mental models for cause of T2D: (a) purely genetic; (b) purely behavioral/environmental; (c) direct multifactorial, in which risk factors interact and over time directly lead to T2D; and (d) indirect multifactorial, in which risk factors interact and over time cause a precursor health condition (such as obesity or metabolic syndrome) that leads to T2D. Interestingly, participants described specific risk factors such as genetics, food habits, lifestyle, weight, and culture as "running in the family." Our findings provide insight into lay beliefs about T2D that can be used by clinicians to anticipate or make sense of responses to questions they pose to patients about mental models for T2D.

  8. Family Planning Policy Environment in the Democratic Republic of the Congo: Levers of Positive Change and Prospects for Sustainability.

    Science.gov (United States)

    Mukaba, Thibaut; Binanga, Arsene; Fohl, Sarah; Bertrand, Jane T

    2015-06-17

    Building on expressed support from the Prime Minister to the Ministries of Health and Planning, the country's new family planning commitment grew out of: (1) recognition of the impact of family planning on maternal mortality and economic development; (2) knowledge sharing of best practices from other African countries; (3) participatory development of a national strategic plan; (4) strong collaboration between stakeholders; (5) effective advocacy by champions including country and international experts; and (6) increased donor support. The question becomes: Will the favorable policy environment translate into effective local programming?

  9. The aberrant millipede genus Pteridoiulus and its position in a revised molecular phylogeny of the family Julidae (Diplopoda : Julida)

    DEFF Research Database (Denmark)

    Enghoff, Henrik; Petersen, Gitte; Seberg, Ole

    2013-01-01

    A phylogenetic analysis of 62 species (32 genera) of the Palaearctic millipede family Julidae, including the aberrant alpine genus Pteridoiulus Verhoeff, 1913, was made based on partial sequences of the mitochondrial 16S rRNA (16S) gene and the nuclear 28SrRNA(28S) gene, respectively. The two......MAFTTand run inTNT both with gaps treated as a fifth state, and as missing, and finally the alignments were used as input in a maximum likelihood (ML) analysis. The order Julida and the family Julidae were recovered as monophyletic under all weight sets in POY, as well as in the TNT andMLanalyses. Likewise...

  10. Change in Autism Symptoms and Maladaptive Behaviors in Adolescence and Adulthood: The Role of Positive Family Processes

    Science.gov (United States)

    Woodman, Ashley C.; Smith, Leann E.; Greenberg, Jan S.; Mailick, Marsha R.

    2015-01-01

    Little is known about outcomes for individuals with autism spectrum disorders (ASD) into adulthood. Several characteristics of individuals with ASD predict long-term outcomes, and the family environment may also play a role. The present study uses a prospective, longitudinal design to describe and predict trajectories of autism symptoms and…

  11. 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.

  12. Hope for the Future But Fear the Risk of Stigma: Ethiopian Family Caregivers' Lived Experience of Caring for Their HIV Positive Child Two Years After Starting Antiretroviral Treatment.

    Science.gov (United States)

    Biru, Mulatu; Lunqvist, Pia; Molla, Mitikie; Jerene, Degu; Hallström, Inger

    2017-12-08

    Family caregivers are believed to be the primary source of support for HIV-affected children. There is limited evidence about practices of support for caregivers, to strengthen them and to enhance the welfare of HIV positive children, especially in African settings. Our aim was therefore to illuminate caregivers' lived experiences of caring for a child in Ethiopia 2 years after the child was enrolled in antiretroviral therapy. Qualitative interviews with 18 family caregivers of 18 children were performed and analyzed using an inductive design with a hermeneutic phenomenological approach. The family caregivers' lived experience was shown in two main themes comprising "lifelong medication gives hope for the future" and "support challenged by the fear of stigma." The family caregivers experienced hope and dreams for the future as they saw their child as healthy and they had regained normality in life after the child's diagnosis. The caregivers still feared the disclosure of the child's diagnosis, which gave rise to conflicts with the child, the family, and society. Good quality support from the healthcare staff lightened their burdens. Further studies are recommended on the strategies of stigma reduction and developing need-specific modalities to support caregivers in the community.

  13. 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

  14. 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.

  15. Change in Autism Symptoms and Maladaptive Behaviors in Adolescence and Adulthood: The Role of Positive Family Processes

    OpenAIRE

    Woodman, Ashley C.; Smith, Leann E.; Greenberg, Jan S.; Mailick, Marsha R.

    2015-01-01

    Little is known about outcomes for individuals with autism spectrum disorders (ASD) into adulthood. Several characteristics of individuals with ASD predict long-term outcomes, and the family environment may also play a role. The present study uses a prospective, longitudinal design to describe and predict trajectories of autism symptoms and maladaptive behaviors over 8.5 years in a large, community-based sample of adolescents and adults with ASD. Overall, autism symptoms and maladaptive behav...

  16. 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

  17. 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

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. Aspartic acid at position 57 of the HLA-DQ beta chain protects against type I diabetes: a family study.

    OpenAIRE

    Morel, P A; Dorman, J S; Todd, J A; McDevitt, H O; Trucco, M

    1988-01-01

    One hundred seventy-two members from 27 randomly selected multiple case Caucasian families of patients with insulin-dependent diabetes mellitus (IDDM) were studied at the DNA level to ascertain the reliability of codon 57 of the HLA-DQ beta-chain gene as a disease protection/susceptibility marker. The analysis was carried out by polymerase chain reaction amplification of DNA encoding the first domain of the DQ beta chain and by dot blot analysis of the amplified material with allele-specific ...

  3. 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

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  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. 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.

  10. 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

  11. 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

  12. Modulating the Physical and Electronic Properties over Positional Isomerism: The Dispirofluorene-Dihydroindacenodithiophene (DSF-IDT) Family.

    Science.gov (United States)

    Peltier, Jean-David; Heinrich, Benoît; Donnio, Bertrand; Jeannin, Olivier; Rault-Berthelot, Joëlle; Poriel, Cyril

    2017-12-06

    We report the first studies on the intrinsic properties of a meta-substituted dihydroindacenodithienyl fragment and more generally the strong impact of positional isomerism on dihydroindacenodithiophene derivatives. The influence of the para and meta linkages has notably been highlighted not only for the electronic properties in solution (electrochemical properties, anodic polymerization, HOMO/LUMO energy levels, optical transitions, fluorescence spectra) but also on the physical properties in the solid state (molecular organization, crystallinity, and phase transitions). The positional isomerism hence appears to be a very efficient tool to drastically tune the properties of dihydroindacenodithiophene derivatives. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. 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.

  14. Written Communication with Families during the Transition from Childcare to School: How Documents Construct and Position Children, Professionals, and Parents

    Science.gov (United States)

    Lehrer, Joanne S.

    2018-01-01

    This article explores how documents play a role in shaping perceptions of children, professionals, and parents during the transition from childcare to kindergarten in Québec. Positioning analysis was used to explore governmentality, documentality, and interobjectivity in the communication agendas and child assessment documents of seven children.…

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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.)

  20. 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.

  1. 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)

  2. 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)

  3. 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

  4. Efficacy of the Video-feedback Intervention to promote Positive Parenting and Sensitive Discipline in Twin Families (VIPP-Twins): Study protocol for a randomized controlled trial.

    Science.gov (United States)

    Euser, Saskia; Bakermans-Kranenburg, Marian J; van den Bulk, Bianca G; Linting, Mariëlle; Damsteegt, Rani C; Vrijhof, Claudia I; van Wijk, Ilse C; Crone, Eveline A; van IJzendoorn, Marinus H

    2016-06-06

    Intervention programs with the aim of enhancing parenting quality have been found to be differentially effective in decreasing negative child outcomes such as externalizing behavioral problems, resulting in modest overall effect sizes. Here we present the protocol for a randomized controlled trial to examine the efficacy of the Video-feedback Intervention to promote Positive Parenting and Sensitive Discipline for Twin Families (VIPP-Twins) on parenting quality and children's behavioral control and social competence. In addition, we aim to test the differential susceptibility theory; we examine differential efficacy of the intervention based on genetic make-up or temperament for both parents and children. Lastly, we explore neurobiological mechanisms underlying intervention effects on children's developmental outcomes. The original VIPP-SD was adapted for use in families with twins. The VIPP-Twins consists of five biweekly sessions in which the families are visited at home, parent-child interactions are videotaped and parents receive positive feedback on selected video fragments. Families (N = 225) with a same sex twin (mean age = 3.6 years) were recruited to participate in the study. The study consists of four assessments. After two baseline assessments in year 1 and year 2, a random 40 % of the sample will receive the VIPP-Twins program. The first post-test assessment will be carried out one month after the intervention and there will be a long term follow-up assessment two years after the intervention. Measures include observational assessments of parenting and children's social competence and behavioral control, and neurobiological assessments (i.e., hormonal functioning and neural (re-)activity). Results of the study will provide insights in the efficacy of the VIPP-Twins and reveal moderators and mediators of program efficacy. Overall the randomized controlled trial is an experimental test of the differential susceptibility theory. Dutch Trial

  5. [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.

  6. What Factors Are Associated with Positive Effects of Dog Ownership in Families with Children with Autism Spectrum Disorder? The Development of the Lincoln Autism Pet Dog Impact Scale.

    Directory of Open Access Journals (Sweden)

    Sophie Susannah Hall

    Full Text Available Scientific literature exploring the value of assistance dogs to children with autism spectrum disorder (ASD is rapidly emerging. However, there is comparably less literature reporting the effects of pet (as opposed to assistance dogs to these children. In particular, there are no known validated scales which assess how children may alter their behaviours in the presence of the dog, to evaluate the efficacy of pet dogs to these families. Additionally, given the highly individualised nature of ASD it is likely that some children and families gain more benefits from dog ownership than others, yet no research has reported the effect of individual differences. This pilot study reports the development of a 28-item scale based on the perceived impact of a pet dog on a child with autism by parents (Lincoln Autism Pet Dog Impact Scale--LAPDIS. The scale is comprised of three mathematically derived factors: Adaptability, Social Skills and Conflict Management. We assessed how individual differences (aspects may be associated with scores on these three factors. Family Aspects and Dog Aspects were not significantly associated with ratings on the three factors, but Child Aspects (including: contact with horses, child age, disability level and language abilities were related to impact of the dog on all factors. Training Aspects were related to scores on Social Skills (formal training with children with ASD and dogs and attendance at PAWS workshops run by Dogs for Good. These results suggest that individual differences associated with the child and the training approach may be important considerations for a positive impact from dog ownership on families with children with ASD. Differences in family features and the dog may not be so important, but may be worthy of further investigations given the early stage of development in this field.

  7. What Factors Are Associated with Positive Effects of Dog Ownership in Families with Children with Autism Spectrum Disorder? The Development of the Lincoln Autism Pet Dog Impact Scale.

    Science.gov (United States)

    Hall, Sophie Susannah; Wright, Hannah F; Mills, Daniel Simon

    2016-01-01

    Scientific literature exploring the value of assistance dogs to children with autism spectrum disorder (ASD) is rapidly emerging. However, there is comparably less literature reporting the effects of pet (as opposed to assistance) dogs to these children. In particular, there are no known validated scales which assess how children may alter their behaviours in the presence of the dog, to evaluate the efficacy of pet dogs to these families. Additionally, given the highly individualised nature of ASD it is likely that some children and families gain more benefits from dog ownership than others, yet no research has reported the effect of individual differences. This pilot study reports the development of a 28-item scale based on the perceived impact of a pet dog on a child with autism by parents (Lincoln Autism Pet Dog Impact Scale--LAPDIS). The scale is comprised of three mathematically derived factors: Adaptability, Social Skills and Conflict Management. We assessed how individual differences (aspects) may be associated with scores on these three factors. Family Aspects and Dog Aspects were not significantly associated with ratings on the three factors, but Child Aspects (including: contact with horses, child age, disability level and language abilities) were related to impact of the dog on all factors. Training Aspects were related to scores on Social Skills (formal training with children with ASD and dogs and attendance at PAWS workshops run by Dogs for Good). These results suggest that individual differences associated with the child and the training approach may be important considerations for a positive impact from dog ownership on families with children with ASD. Differences in family features and the dog may not be so important, but may be worthy of further investigations given the early stage of development in this field.

  8. Social support among HIV-positive and HIV-negative adolescents in Umlazi, South Africa: changes in family and partner relationships during pregnancy and the postpartum period.

    Science.gov (United States)

    Hill, Lauren M; Maman, Suzanne; Groves, Allison K; Moodley, Dhayendre

    2015-05-17

    Pregnancy is common among adolescents in South Africa, yet the social experiences of adolescents during the pregnancy and postpartum period remain understudied in this context. We aimed to explore how adolescent women's discovery and disclosure of both their pregnancy and HIV status affected their relationships with family members and sexual partners, with a particular focus on whether and how support changed throughout this time period. We conducted in-depth semi-structured interviews with 15 HIV-positive and HIV-negative adolescent women who were either pregnant or had delivered in the last 18 months from one urban clinic in Umlazi, South Africa. Interviews were audiotaped, transcribed, translated, and coded for analysis. Young women described stress and instability in their relationships with family and partners during pregnancy and the postpartum period, though prior to and during HIV-status disclosure women generally experienced less stress than in disclosing their pregnancy to family members and partners. After a destabilizing period immediately following pregnancy disclosure, families became and remained the primary source of material and emotional support for the young women. Women discussed heightened closeness with their partners during pregnancy, but few women had close relationships with their partners postpartum. Support experiences did not differ by HIV status. Programs should be aware of the relative importance of pregnancy-related concerns over HIV-related concerns in this population of young women. Engaging family members is critical in ensuring social support for this population of young pregnant women, and in encouraging timely initiation of antenatal care.

  9. Positive Impact on Physical Activity and Health Behaviour Changes of a 15-Week Family Focused Intervention Program: "Juniors for Seniors".

    Science.gov (United States)

    Bronikowski, Michał; Bronikowska, Małgorzata; Pluta, Beata; Maciaszek, Janusz; Tomczak, Maciej; Glapa, Agata

    2016-01-01

    The promotion of physical activity (PA) in children and their parents requires effective planning and sometimes even interventions. This study shows the effect of PA during a 15-week intervention program "Junior for Seniors" by applying a socioecological model to the interpretation of the data. This comprehensive approach emphasizes the fact that health promotion should focus not only on intrapersonal factors but also on the multilevel factors that might be determinants and modulators of increased PA. In 2015, 24 children ("juniors," 14 girls and 10 boys, aged M = 7.96 ± 0.69) and 22 parents ("seniors," 14 mothers aged M = 38.86 ± 2.96 and 8 fathers aged M = 37.38 ± 2.97) were voluntarily enrolled in a study spread across three primary schools in the city of Poznań, Poland. The effectiveness of the intervention was determined according to postintervention behavioural changes in PA in comparison to preintervention levels, as reported by the parents and children. Overall, the study found increases in PA levels and reductions in sedentary time. Although the changes are modest, there are some unrecognized benefits of the intervention which may have occurred, such as improved sport and motor skills, more frequent family social behaviours (walks, meals, and visiting relatives), or simply improved quality of "do-together" leisure time PA.

  10. 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...

  11. Positive Selection Drives the Evolution of rhino, a Member of the Heterochromatin Protein 1 Family in Drosophila.

    Directory of Open Access Journals (Sweden)

    2005-07-01

    Full Text Available Heterochromatin comprises a significant component of many eukaryotic genomes. In comparison to euchromatin, heterochromatin is gene poor, transposon rich, and late replicating. It serves many important biological roles, from gene silencing to accurate chromosome segregation, yet little is known about the evolutionary constraints that shape heterochromatin. A complementary approach to the traditional one of directly studying heterochromatic DNA sequence is to study the evolution of proteins that bind and define heterochromatin. One of the best markers for heterochromatin is the heterochromatin protein 1 (HP1, which is an essential, nonhistone chromosomal protein. Here we investigate the molecular evolution of five HP1 paralogs present in Drosophila melanogaster. Three of these paralogs have ubiquitous expression patterns in adult Drosophila tissues, whereas HP1D/rhino and HP1E are expressed predominantly in ovaries and testes respectively. The HP1 paralogs also have distinct localization preferences in Drosophila cells. Thus, Rhino localizes to the heterochromatic compartment in Drosophila tissue culture cells, but in a pattern distinct from HP1A and lysine-9 dimethylated H3. Using molecular evolution and population genetic analyses, we find that rhino has been subject to positive selection in all three domains of the protein: the N-terminal chromo domain, the C-terminal chromo-shadow domain, and the hinge region that connects these two modules. Maximum likelihood analysis of rhino sequences from 20 species of Drosophila reveals that a small number of residues of the chromo and shadow domains have been subject to repeated positive selection. The rapid and positive selection of rhino is highly unusual for a gene encoding a chromosomal protein and suggests that rhino is involved in a genetic conflict that affects the germline, belying the notion that heterochromatin is simply a passive recipient of "junk DNA" in eukaryotic genomes.

  12. Positive selection drives the evolution of rhino, a member of the heterochromatin protein 1 family in Drosophila.

    Directory of Open Access Journals (Sweden)

    Danielle Vermaak

    2005-07-01

    Full Text Available Heterochromatin comprises a significant component of many eukaryotic genomes. In comparison to euchromatin, heterochromatin is gene poor, transposon rich, and late replicating. It serves many important biological roles, from gene silencing to accurate chromosome segregation, yet little is known about the evolutionary constraints that shape heterochromatin. A complementary approach to the traditional one of directly studying heterochromatic DNA sequence is to study the evolution of proteins that bind and define heterochromatin. One of the best markers for heterochromatin is the heterochromatin protein 1 (HP1, which is an essential, nonhistone chromosomal protein. Here we investigate the molecular evolution of five HP1 paralogs present in Drosophila melanogaster. Three of these paralogs have ubiquitous expression patterns in adult Drosophila tissues, whereas HP1D/rhino and HP1E are expressed predominantly in ovaries and testes respectively. The HP1 paralogs also have distinct localization preferences in Drosophila cells. Thus, Rhino localizes to the heterochromatic compartment in Drosophila tissue culture cells, but in a pattern distinct from HP1A and lysine-9 dimethylated H3. Using molecular evolution and population genetic analyses, we find that rhino has been subject to positive selection in all three domains of the protein: the N-terminal chromo domain, the C-terminal chromo-shadow domain, and the hinge region that connects these two modules. Maximum likelihood analysis of rhino sequences from 20 species of Drosophila reveals that a small number of residues of the chromo and shadow domains have been subject to repeated positive selection. The rapid and positive selection of rhino is highly unusual for a gene encoding a chromosomal protein and suggests that rhino is involved in a genetic conflict that affects the germline, belying the notion that heterochromatin is simply a passive recipient of "junk DNA" in eukaryotic genomes.

  13. Exponent Rummy

    Science.gov (United States)

    Griffith, Leah

    2016-01-01

    Classroom teachers try to provide opportunities for students to practice and use the algebra skills they are learning in ways that are nonroutine. They also want to help students connect the big ideas of math with the skills they are learning as part of the balance between understanding concepts and procedures. Math games can be used to accomplish…

  14. 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

  15. 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.

  16. 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 ...

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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

  2. 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

  3. 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

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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

  9. 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.

  10. 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.

  11. 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

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. OA20 The positioning of family, friends, community, and service providers in support networks for caring at end-of-life: a social network analysis.

    Science.gov (United States)

    Leonard, Rosemary; Horsfall, Debbie; Rosenberg, John; Noonan, Kerrie

    2015-04-01

    Although there is ample evidence of the risk to carers from the burden of caring, there is also evidence that a caring network can relieve the burden on the principal carer, strengthen community relationships, and increase 'Death Literacy' in the community. There is often an assumption that, in caring networks, family and service providers are central and friends and community are marginal. We examined whether this is the case in practice using SNA. To identify the relative positioning of family, friends, community, and service providers in caring networks. In interviews with carers (N = 23) and focus groups with caring networks (N = 13) participants were asked to list the people in the caring network and rate the strength of their relationships to them (0 no relationship to 3 strong relationship). SNA in UCInet was used to map the networks, examine density (number and strength of relationships) across time (when caring began to the present) and across relationship types (family, friends, community, and service providers) supplemented by qualitative data. The analysis revealed significant increases in the density of the networks over time. The density of relationships with friends was similar to that other family. Community and service providers had significantly lower density. Qualitative analysis revealed that often service providers were not seen as part of the networks. To avoid carer burnout, it is important not to make assumptions about where carers obtain support but work with each carer to mobilise any support that is available. © 2015, Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  18. 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

  19. Demand for family planning among HIV positive women on ART: the case of South Gondar and North Wollo Zones Amhara region.

    Science.gov (United States)

    Abeje, Gedefaw; Motbaynor, Achenef

    2016-01-25

    Although family planning for human immune deficiency virus positive women has numerous advantages, evidences in different parts of the world showed the existence of persistent unmet need. There were few studies done in Ethiopia on level of unmet need for family planning among women in reproductive age on antiretroviral therapy (ART). This study was therefore done to determine the level of demand and unmet need for family planning among women on ART in South Gondar and North Wollo Zones, Amhara region. Institution based cross-sectional study design was used. Data was collected from June 15 to 25, 2013 in South Gondar and North Wollo Zones. Study participants were recruited from six health centers and two hospitals. The study participants were proportionally allocated to the health institutions. Multistage sampling technique was used to recruit study participants. Trained nurses interviewed the respondents using pretested structured Amharic questionnaire. Data was entered, cleaned and analyzed using Statistical Package for Social Science version 16. Ratios and proportions were computed to determine demand and unmet need for family planning. A total of 530 women in reproductive age on ART were interviewed in this study. Two hundred ninety-three women were married. Fourteen (2.6%) women were pregnant at the time of interview. Five of these pregnancies were not planned. In this study, 242 (45.7%) women reported that they were using contraceptives. Most women (74.4%) were using injectable (depo). Among those who were not using contraceptives, 84 (29.2%) reported that they will use in the future. Fifty-two (61.9%) of them said that they will use injectables (depo). In this study, the total demand for family planning among women on ART was 86.7%. From this, 62.1% and 24.6% was met and unmet need respectively. This study revealed that the level of demand and met need for modern contraceptives among reproductive age women on antiretroviral therapy in South Gondar and North

  20. 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.

  1. 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

  2. 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

  3. 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.

  4. 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

  5. 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.

  6. 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.

  7. 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.

  8. 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

  9. 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.

  10. 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

  11. 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

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. 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)

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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

  3. 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.

  4. 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.)

  5. 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)

  6. 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

  7. 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)

  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. 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.

  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. 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)

  12. 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.

  13. 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...

  14. 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...

  15. 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.

  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. 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...

  18. 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

  19. 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

  20. 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

  1. Gender inequality in self-reported health among the elderly in contemporary welfare countries: A cross-country analysis of time use activities, socioeconomic positions and family characteristics.

    Science.gov (United States)

    Adjei, Nicholas Kofi; Brand, Tilman; Zeeb, Hajo

    2017-01-01

    Paradoxically, despite their longer life expectancy, women report poorer health than men. Time devoted to differing social roles could be an explanation for the observed gender differences in health among the elderly. The objective of this study was to explain gender differences in self-reported health among the elderly by taking time use activities, socio-economic positions, family characteristics and cross-national differences into account. Data from the Multinational Time Use Study (MTUS) on 13,223 men and 18,192 women from Germany, Italy, Spain, UK and the US were analyzed. Multiple binary logistic regression models were used to examine the association between social factors and health for men and women separately. We further identified the relative contribution of different factors to total gender inequality in health using the Blinder-Oaxaca decomposition method. Whereas time allocated to paid work, housework and active leisure activities were positively associated with health, time devoted to passive leisure and personal activities were negatively associated with health among both men and women, but the magnitude of the association varied by gender and country. We found significant gender differences in health in Germany, Italy and Spain, but not in the other countries. The decomposition showed that differences in the time allocated to active leisure and level of educational attainment accounted for the largest health gap. Our study represents a first step in understanding cross-national differences in the association between health status and time devoted to role-related activities among elderly men and women. The results, therefore, demonstrate the need of using an integrated framework of social factors in analyzing and explaining the gender and cross-national differences in the health of the elderly population.

  2. Gender inequality in self-reported health among the elderly in contemporary welfare countries: A cross-country analysis of time use activities, socioeconomic positions and family characteristics.

    Directory of Open Access Journals (Sweden)

    Nicholas Kofi Adjei

    Full Text Available Paradoxically, despite their longer life expectancy, women report poorer health than men. Time devoted to differing social roles could be an explanation for the observed gender differences in health among the elderly. The objective of this study was to explain gender differences in self-reported health among the elderly by taking time use activities, socio-economic positions, family characteristics and cross-national differences into account.Data from the Multinational Time Use Study (MTUS on 13,223 men and 18,192 women from Germany, Italy, Spain, UK and the US were analyzed. Multiple binary logistic regression models were used to examine the association between social factors and health for men and women separately. We further identified the relative contribution of different factors to total gender inequality in health using the Blinder-Oaxaca decomposition method.Whereas time allocated to paid work, housework and active leisure activities were positively associated with health, time devoted to passive leisure and personal activities were negatively associated with health among both men and women, but the magnitude of the association varied by gender and country. We found significant gender differences in health in Germany, Italy and Spain, but not in the other countries. The decomposition showed that differences in the time allocated to active leisure and level of educational attainment accounted for the largest health gap.Our study represents a first step in understanding cross-national differences in the association between health status and time devoted to role-related activities among elderly men and women. The results, therefore, demonstrate the need of using an integrated framework of social factors in analyzing and explaining the gender and cross-national differences in the health of the elderly population.

  3. Gender inequality in self-reported health among the elderly in contemporary welfare countries: A cross-country analysis of time use activities, socioeconomic positions and family characteristics

    Science.gov (United States)

    Adjei, Nicholas Kofi; Brand, Tilman; Zeeb, Hajo

    2017-01-01

    Background Paradoxically, despite their longer life expectancy, women report poorer health than men. Time devoted to differing social roles could be an explanation for the observed gender differences in health among the elderly. The objective of this study was to explain gender differences in self-reported health among the elderly by taking time use activities, socio-economic positions, family characteristics and cross-national differences into account. Methods Data from the Multinational Time Use Study (MTUS) on 13,223 men and 18,192 women from Germany, Italy, Spain, UK and the US were analyzed. Multiple binary logistic regression models were used to examine the association between social factors and health for men and women separately. We further identified the relative contribution of different factors to total gender inequality in health using the Blinder-Oaxaca decomposition method. Results Whereas time allocated to paid work, housework and active leisure activities were positively associated with health, time devoted to passive leisure and personal activities were negatively associated with health among both men and women, but the magnitude of the association varied by gender and country. We found significant gender differences in health in Germany, Italy and Spain, but not in the other countries. The decomposition showed that differences in the time allocated to active leisure and level of educational attainment accounted for the largest health gap. Conclusions Our study represents a first step in understanding cross-national differences in the association between health status and time devoted to role-related activities among elderly men and women. The results, therefore, demonstrate the need of using an integrated framework of social factors in analyzing and explaining the gender and cross-national differences in the health of the elderly population. PMID:28949984

  4. Drawing on resilience: piloting the utility of the Kinetic Family Drawing to measure resilience in children of HIV-positive mothers

    Directory of Open Access Journals (Sweden)

    L Ebersöhn

    2012-01-01

    Full Text Available In this article we describe how using a visual, child-friendly measure of resilience in a randomised control trial (RCT, the Kgolo Mmogo (KM project, resulted in representative insights on resilience in a mother-child relationship where the mother is HIV-positive. We used the existing psychological method Kinetic Family Drawing (KFD to measure resilience of young children in the qualitative phase of the concurrent mixed method RCT as the children represent cultural groups for whom standardized measures have not been developed. We use the case example of baseline KM assessment data of 6 year olds (n = 11; 3 female, 8 male. The results of the study demonstrate that the visual and qualitative data from children (KFD added to quantitative information obtained from mothers (Vineland Adaptive Behavior Scale, VABS. Additional information from the KFD had interpretation value for VABS scores and provided a child's perspective regarding resilience. Contrasting information from the KFD problematized mothers' perspectives as indicated in the VABS. The absence of significant information in KFD results regarding VABS sub-domains indicates differences in the cultural/contextual conceptualization of resilience. This exploratory study indicates initial support for the cross-cultural utility of the KFD to measure resilience in young children faced with adversity.

  5. 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.

  6. 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

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  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. 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.

  15. 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.

  16. 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

  17. New insights in the interpretation of array-CGH: autism spectrum disorder and positive family history for intellectual disability predict the detection of pathogenic variants.

    Science.gov (United States)

    Cappuccio, Gerarda; Vitiello, Francesco; Casertano, Alberto; Fontana, Paolo; Genesio, Rita; Bruzzese, Dario; Ginocchio, Virginia Maria; Mormile, Angela; Nitsch, Lucio; Andria, Generoso; Melis, Daniela

    2016-04-12

    Array-CGH (aCGH) is presently used into routine clinical practice for diagnosis of patients with intellectual disability (ID), multiple congenital anomalies (MCA), and autism spectrum disorder (ASD). ACGH could detect small chromosomal imbalances, copy number variations (CNVs), and closely define their size and gene content. ACGH detects pathogenic imbalances in 14-20 % of patients with ID. The aims of this study were: to establish clinical clues potentially associated with pathogenic CNVs and to identify cytogenetic indicators to predict the pathogenicity of the variants of uncertain significance (VOUS) in a large cohort of paediatric patients. We enrolled 214 patients referred for either: ID, and/or ASD and/or MCA to genetic services at the Federico II University of Naples, Department of Translational Medicine. For each patient we collected clinical and imaging data. All the patients were tested with aCGH or as first-tier test or as part of a wider diagnostic work-up. Pathologic data were detected in 65 individuals (30 %) and 46 CNVs revealed a known syndrome. The pathological CNVs were usually deletions showing the highest gene-dosage content. The positive family history for ID/ASD/MCA and ASD were good indicators for detecting pathological chromosomal rearrangements. Other clinical features as eyes anomalies, hearing loss, neurological signs, cutaneous dyscromia and endocrinological problems seem to be potential predictors of pathological CNVs. Among patients carrying VOUS we analyzed genetic features including CNVs size, presence of deletion or duplication, genic density, multiple CNVs, to clinical features. Higher gene density was found in patients affected by ID. This result suggest that higher gene content has more chances to include pathogenic gene involved and causing ID in these patients. Our study suggest the use of aCGH as first-tier test in patients with neurdevelopmental phenotypes. The inferred results have been used for building a flow-chart to be

  18. 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.

  19. Do Family Responsibilities and a Clinical Versus Research Faculty Position Affect Satisfaction with Career and Work–Life Balance for Medical School Faculty?

    OpenAIRE

    Beckett, Laurel; Nettiksimmons, Jasmine; Howell, Lydia Pleotis; Villablanca, Amparo C.

    2015-01-01

    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.

  20. Family Involvement with African-American Youth during the Pre-College Years: From a "Psychology of Oppression" to a "Positive Black Psychology"

    Science.gov (United States)

    Jones, Clara B.; Palmer, Julie K.

    2004-01-01

    This paper addresses ways ways in which African-American families can influence their children's development, usually with guidance from school or other community agents. We discuss the importance of "discipline styles" for effective parenting and emphasize an approach to family involvement in child development utilizing a child's strengths. We…

  1. Maintaining positive

    OpenAIRE

    Gheorghe Gh. IONESCU; Adina Letitia NEGRUSA

    2004-01-01

    Maintaining positive work-force relationships includes in effective labor-management relations and making appropriate responses to current employee issues. Among the major current employee issues are protection from arbitrary dismissal, drug and alcohol abuse, privacy rights and family maters and they impact work. In our paper we discus two problems: first, the meanings of industrial democracy; second, the three principal operational concepts of industrial democracy (1) industrial democracy t...

  2. MSH6 and PMS2 mutation positive Australian Lynch syndrome families: novel mutations, cancer risk and age of diagnosis of colorectal cancer.

    Science.gov (United States)

    Talseth-Palmer, Bente A; McPhillips, Mary; Groombridge, Claire; Spigelman, Allan; Scott, Rodney J

    2010-05-21

    Approximately 10% of Lynch syndrome families have a mutation in MSH6 and fewer families have a mutation in PMS2. It is assumed that the cancer incidence is the same in families with mutations in MSH6 as in families with mutations in MLH1/MSH2 but that the disease tends to occur later in life, little is known about families with PMS2 mutations. This study reports on our findings on mutation type, cancer risk and age of diagnosis in MSH6 and PMS2 families. A total of 78 participants (from 29 families) with a mutation in MSH6 and 7 participants (from 6 families) with a mutation in PMS2 were included in the current study. A database of de-identified patient information was analysed to extract all relevant information such as mutation type, cancer incidence, age of diagnosis and cancer type in this Lynch syndrome cohort. Cumulative lifetime risk was calculated utilising Kaplan-Meier survival analysis. MSH6 and PMS2 mutations represent 10.3% and 1.9%, respectively, of the pathogenic mutations in our Australian Lynch syndrome families. We identified 26 different MSH6 and 4 different PMS2 mutations in the 35 families studied. We report 15 novel MSH6 and 1 novel PMS2 mutations. The estimated cumulative risk of CRC at age 70 years was 61% (similar in males and females) and 65% for endometrial cancer in MSH6 mutation carriers. The risk of developing CRC is different between males and females at age 50 years, which is 34% for males and 21% for females. Novel MSH6 and PMS2 mutations are being reported and submitted to the current databases for identified Lynch syndrome mutations. Our data provides additional information to add to the genotype-phenotype spectrum for both MSH6 and PMS2 mutations.

  3. MSH6 and PMS2 mutation positive Australian Lynch syndrome families: novel mutations, cancer risk and age of diagnosis of colorectal cancer

    Directory of Open Access Journals (Sweden)

    Talseth-Palmer Bente A

    2010-05-01

    Full Text Available Abstract Background Approximately 10% of Lynch syndrome families have a mutation in MSH6 and fewer families have a mutation in PMS2. It is assumed that the cancer incidence is the same in families with mutations in MSH6 as in families with mutations in MLH1/MSH2 but that the disease tends to occur later in life, little is known about families with PMS2 mutations. This study reports on our findings on mutation type, cancer risk and age of diagnosis in MSH6 and PMS2 families. Methods A total of 78 participants (from 29 families with a mutation in MSH6 and 7 participants (from 6 families with a mutation in PMS2 were included in the current study. A database of de-identified patient information was analysed to extract all relevant information such as mutation type, cancer incidence, age of diagnosis and cancer type in this Lynch syndrome cohort. Cumulative lifetime risk was calculated utilising Kaplan-Meier survival analysis. Results MSH6 and PMS2 mutations represent 10.3% and 1.9%, respectively, of the pathogenic mutations in our Australian Lynch syndrome families. We identified 26 different MSH6 and 4 different PMS2 mutations in the 35 families studied. We report 15 novel MSH6 and 1 novel PMS2 mutations. The estimated cumulative risk of CRC at age 70 years was 61% (similar in males and females and 65% for endometrial cancer in MSH6 mutation carriers. The risk of developing CRC is different between males and females at age 50 years, which is 34% for males and 21% for females. Conclusion Novel MSH6 and PMS2 mutations are being reported and submitted to the current databases for identified Lynch syndrome mutations. Our data provides additional information to add to the genotype-phenotype spectrum for both MSH6 and PMS2 mutations.

  4. Dynamic stability of running: The effects of speed and leg amputations on the maximal Lyapunov exponent

    International Nuclear Information System (INIS)

    Look, Nicole; Arellano, Christopher J.; Grabowski, Alena M.; Kram, Rodger; McDermott, William J.; Bradley, Elizabeth

    2013-01-01

    In this paper, we study dynamic stability during running, focusing on the effects of speed, and the use of a leg prosthesis. We compute and compare the maximal Lyapunov exponents of kinematic time-series data from subjects with and without unilateral transtibial amputations running at a wide range of speeds. We find that the dynamics of the affected leg with the running-specific prosthesis are less stable than the dynamics of the unaffected leg and also less stable than the biological legs of the non-amputee runners. Surprisingly, we find that the center-of-mass dynamics of runners with two intact biological legs are slightly less stable than those of runners with amputations. Our results suggest that while leg asymmetries may be associated with instability, runners may compensate for this effect by increased control of their center-of-mass dynamics

  5. 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

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. Scaling behavior of knotted random polygons and self-avoiding polygons: Topological swelling with enhanced exponent.

    Science.gov (United States)

    Uehara, Erica; Deguchi, Tetsuo

    2017-12-07

    We show that the average size of self-avoiding polygons (SAPs) with a fixed knot is much larger than that of no topological constraint if the excluded volume is small and the number of segments is large. We call it topological swelling. We argue an "enhancement" of the scaling exponent for random polygons with a fixed knot. We study them systematically through SAP consisting of hard cylindrical segments with various different values of the radius of segments. Here we mean by the average size the mean-square radius of gyration. Furthermore, we show numerically that the topological balance length of a composite knot is given by the sum of those of all constituent prime knots. Here we define the topological balance length of a knot by such a number of segments that topological entropic repulsions are balanced with the knot complexity in the average size. The additivity suggests the local knot picture.

  13. 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.

  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. The influence of young age and positive family history on local recurrence after three treatment strategies for ductal carcinoma in situ

    International Nuclear Information System (INIS)

    Szelei-Stevens, Kathleen A.; Kuske, Robert R.; Bolton, John S.; Bowen, John C.; Fuhrman, George M.; Fineberg, Barbara B.

    1997-01-01

    Purpose: Three recent studies have investigated the influence of a positive family history (+FH) of breast cancer on the prognosis of DCIS patients treated by conservative surgery and radiation therapy (CS+RT), with two studies showing a higher risk of locoregional relapse (LRR) in these patients (pts) and another showing no significant difference. Since three treatment strategies have been used for DCIS at our institution, we evaluated the influence of +FH and young age on outcome by treatment method. Materials and Methods: Between 1/1/82 and 12/31/92, one hundred and twenty-eight pts were treated for DCIS by mastectomy (Mast) (n=50, 39%), local excision alone (Loc Exc) (n=43, 34%), and CS+RT (n=35, 27%). No pts were lost to follow-up. Median follow-up (FUP) is 6.0 years. Median age was 59 years (range 28 to 86). Thirty-nine pts had a +FH of breast cancer, 26 in a first-degree relative (mother or sister), and 26 in a second-degree relative (grandmother, aunt, or cousin). Thirteen pts had a +FH in both first and second-degree relatives. Final margins of resection were positive in three pts, negative in 97, and unknown in 28. Thirty-four pts had comedo histologic subtype. Results: Six women developed a recurrence in the treated breast, and all of these were initially treated by Loc Exc. There were no recurrences in the Mast or CS+RT groups. The five year overall actuarial LRR rate was 95.2%. The 5- and 10-year overall survival (OS) rates were 95.4% and 85.7% respectively. The cause-specific survival (CSS) was 99.2% and 97.3% at 5 and 10 years. Pts with a +FH had a 10.3% LRR, versus a 2.3% LRR for pts with a negative FH (p 0.05). Four of 44 pts (9.1%) 50 years of age or younger recurred, compared to 2 of 84 pts (2.4%) over the age of 50 (p = 0.10). Fifteen pts in this study had both a +FH and were 50 years of age or younger. Among these women, the recurrence rate was 20%. Women in this group treated by Loc Exc had a LRR of 38% (3 of 8). Other factors such as

  16. 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.

  17. 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)

  18. 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.)

  19. Global history of the ancient monocot family Araceae inferred with models accounting for past continental positions and previous ranges based on fossils.

    Science.gov (United States)

    Nauheimer, Lars; Metzler, Dirk; Renner, Susanne S

    2012-09-01

    The family Araceae (3790 species, 117 genera) has one of the oldest fossil records among angiosperms. Ecologically, members of this family range from free-floating aquatics (Pistia and Lemna) to tropical epiphytes. Here, we infer some of the macroevolutionary processes that have led to the worldwide range of this family and test how the inclusion of fossil (formerly occupied) geographical ranges affects biogeographical reconstructions. Using a complete genus-level phylogeny from plastid sequences and outgroups representing the 13 other Alismatales families, we estimate divergence times by applying different clock models and reconstruct range shifts under different models of past continental connectivity, with or without the incorporation of fossil locations. Araceae began to diversify in the Early Cretaceous (when the breakup of Pangea was in its final stages), and all eight subfamilies existed before the K/T boundary. Early lineages persist in Laurasia, with several relatively recent entries into Africa, South America, South-East Asia and Australia. Water-associated habitats appear to be ancestral in the family, and DNA substitution rates are especially high in free-floating Araceae. Past distributions inferred when fossils are included differ in nontrivial ways from those without fossils. Our complete genus-level time-scale for the Araceae may prove to be useful for ecological and physiological studies. © 2012 The Authors. New Phytologist © 2012 New Phytologist Trust.

  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. 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.

  2. 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.

  3. Competitive autocatalytic reactions in chaotic flows with diffusion: Prediction using finite-time Lyapunov exponents

    International Nuclear Information System (INIS)

    Schlick, Conor P.; Umbanhowar, Paul B.; Ottino, Julio M.; Lueptow, Richard M.

    2014-01-01

    We investigate chaotic advection and diffusion in autocatalytic reactions for time-periodic sine flow computationally using a mapping method with operator splitting. We specifically consider three different autocatalytic reaction schemes: a single autocatalytic reaction, competitive autocatalytic reactions, which can provide insight into problems of chiral symmetry breaking and homochirality, and competitive autocatalytic reactions with recycling. In competitive autocatalytic reactions, species B and C both undergo an autocatalytic reaction with species A such that A+B→2B and A+C→2C. Small amounts of initially spatially localized B and C and a large amount of spatially homogeneous A are advected by the velocity field, diffuse, and react until A is completely consumed and only B and C remain. We find that local finite-time Lyapunov exponents (FTLEs) can accurately predict the final average concentrations of B and C after the reaction completes. The species that starts in the region with the larger FTLE has, with high probability, the larger average concentration at the end of the reaction. If B and C start in regions with similar FTLEs, their average concentrations at the end of the reaction will also be similar. When a recycling reaction is added, the system evolves towards a single species state, with the FTLE often being useful in predicting which species fills the entire domain and which is depleted. The FTLE approach is also demonstrated for competitive autocatalytic reactions in journal bearing flow, an experimentally realizable flow that generates chaotic dynamics

  4. Hurst exponent: A Brownian approach to characterize the nonlinear behavior of red blood cells deformability

    Science.gov (United States)

    Mancilla Canales, M. A.; Leguto, A. J.; Riquelme, B. D.; León, P. Ponce de; Bortolato, S. A.; Korol, A. M.

    2017-12-01

    Ektacytometry techniques quantifies red blood cells (RBCs) deformability by measuring the elongation of suspended RBCs subjected to shear stress. Raw shear stress elongation plots are difficult to understand, thus most research papers apply data reduction methods characterizing the relationship between curve fitting. Our approach works with the naturally generated photometrically recorded time series of the diffraction pattern of several million of RBCs subjected to shear stress, and applies nonlinear quantifiers to study the fluctuations of these elongations. The development of new quantitative methods is crucial for restricting the subjectivity in the study of the cells behavior, mainly if they are capable of analyze at the same time biological and mechanical aspects of the cells in flowing conditions and compare their dynamics. A patented optical system called Erythrocyte Rheometer was used to evaluate viscoelastic properties of erythrocytes by Ektacytometry. To analyze cell dynamics we used the technique of Time Delay Coordinates, False Nearest Neighbors, the forecasting procedure proposed by Sugihara and May, and Hurst exponent. The results have expressive meaning on comparing healthy samples with parasite treated samples, suggesting that apparent noise associated with deterministic chaos can be used not only to distinguish but also to characterize biological and mechanical aspects of cells at the same time in flowing conditions.

  5. 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.

  6. 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.

  7. Variability of aerosol optical depth and Angstrom wavelength exponent derived from AERONET observations in recent decades

    International Nuclear Information System (INIS)

    Xia Xiangao

    2011-01-01

    Using aerosol loading data from 79 Aerosol Robotic Network (AERONET) stations with observations from more than six years, changes in aerosol optical depth (AOD) and Angstrom wavelength exponent (AWE) were studied. A statistical method was developed to determine whether AOD changes were due to increased background AOD values and/or an increased number of high AOD events. AOD decreased significantly at AERONET sites in northeastern North American and in Western Europe, which was accompanied by decreased AWE. Reduction of AOD there was mainly due to a decreased frequency of high AOD events and an increased frequency of background AOD events. In addition, decreased AOD values for high AOD events also accounted for ∼ 16–32% of the AOD reduction. This is indicative of significant meteorological effects on AOD variability. AOD trends in other regions were marginal and most were not significant; however, AOD increased significantly at one site in the Sahel and another in Saudi Arabia, predominantly due to the increased frequency of high AOD events and their average AOD.

  8. Spike solutions in Gierer#x2013;Meinhardt model with a time dependent anomaly exponent

    Science.gov (United States)

    Nec, Yana

    2018-01-01

    Experimental evidence of complex dispersion regimes in natural systems, where the growth of the mean square displacement in time cannot be characterised by a single power, has been accruing for the past two decades. In such processes the exponent γ(t) in ⟨r2⟩ ∼ tγ(t) at times might be approximated by a piecewise constant function, or it can be a continuous function. Variable order differential equations are an emerging mathematical tool with a strong potential to model these systems. However, variable order differential equations are not tractable by the classic differential equations theory. This contribution illustrates how a classic method can be adapted to gain insight into a system of this type. Herein a variable order Gierer-Meinhardt model is posed, a generic reaction- diffusion system of a chemical origin. With a fixed order this system possesses a solution in the form of a constellation of arbitrarily situated localised pulses, when the components' diffusivity ratio is asymptotically small. The pattern was shown to exist subject to multiple step-like transitions between normal diffusion and sub-diffusion, as well as between distinct sub-diffusive regimes. The analytical approximation obtained permits qualitative analysis of the impact thereof. Numerical solution for typical cross-over scenarios revealed such features as earlier equilibration and non-monotonic excursions before attainment of equilibrium. The method is general and allows for an approximate numerical solution with any reasonably behaved γ(t).

  9. Black Carbon, Aerosol optical depth and Angstrom Exponent in São Paulo, Brazil

    Science.gov (United States)

    Miranda, R. M.; Perez-Martinez, P. J.; Andrade, M. D. F.

    2017-12-01

    Black carbon (BC) is a major absorber of solar radiation, and its impact on the radiative balance is therefore considered important. Fossil fuel combustion processes and biomass burning result in the emission of BC. Black carbon is being monitored since 2014 with a Multi-Angle Absorption Photometer-MAAP (5012; Thermo Scientific) in the East Zone of São Paulo, Brazil. São Paulo Metropolitan Area with more than 19 million inhabitants, 7 million vehicles, has high concentrations of air pollutants, especially in the winter. Vehicles can be considered the principal source of particles emitted to the atmosphere. Concentration of the pollutant had an average of 1.95 ug.m-3 ± 2.06 and a maximum value of 19.93 ug.m-3. These large variations were due to meteorological effects and to the influence of anthropogenic activities, since samples were collected close to important highways. Winds coming from the East part predominate. Higher concentrations were found in the winter months (June, July and August). Optical data from AERONET (Aerosol Optical Depth-AOD 550 nm and Angstrom Exponent 440-675 nm) were related to BC concentrations for the period from August, 2016. Average values of AOD at 500 nm and Angstrom Parameter (440-675nm) were 0.16±0.11 and 1.44±0.23, respectively. Higher BC concentrations were related to lower Angstrom values.

  10. 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.

  11. A perturbation method to the tent map based on Lyapunov exponent and its application

    Science.gov (United States)

    Cao, Lv-Chen; Luo, Yu-Ling; Qiu, Sen-Hui; Liu, Jun-Xiu

    2015-10-01

    Perturbation imposed on a chaos system is an effective way to maintain its chaotic features. A novel parameter perturbation method for the tent map based on the Lyapunov exponent is proposed in this paper. The pseudo-random sequence generated by the tent map is sent to another chaos function — the Chebyshev map for the post processing. If the output value of the Chebyshev map falls into a certain range, it will be sent back to replace the parameter of the tent map. As a result, the parameter of the tent map keeps changing dynamically. The statistical analysis and experimental results prove that the disturbed tent map has a highly random distribution and achieves good cryptographic properties of a pseudo-random sequence. As a result, it weakens the phenomenon of strong correlation caused by the finite precision and effectively compensates for the digital chaos system dynamics degradation. Project supported by the Guangxi Provincial Natural Science Foundation, China (Grant No. 2014GXNSFBA118271), the Research Project of Guangxi University, China (Grant No. ZD2014022), the Fund from Guangxi Provincial Key Laboratory of Multi-source Information Mining & Security, China (Grant No. MIMS14-04), the Fund from the Guangxi Provincial Key Laboratory of Wireless Wideband Communication & Signal Processing, China (Grant No. GXKL0614205), the Education Development Foundation and the Doctoral Research Foundation of Guangxi Normal University, the State Scholarship Fund of China Scholarship Council (Grant No. [2014]3012), and the Innovation Project of Guangxi Graduate Education, China (Grant No. YCSZ2015102).

  12. The Tail Exponent for Stock Returns in Bursa Malaysia for 2003-2008

    Science.gov (United States)

    Rusli, N. H.; Gopir, G.; Usang, M. D.

    2010-07-01

    A developed discipline of econophysics that has been introduced is exhibiting the application of mathematical tools that are usually applied to the physical models for the study of financial models. In this study, an analysis of the time series behavior of several blue chip and penny stock companies in Main Market of Bursa Malaysia has been performed. Generally, the basic quantity being used is the relative price changes or is called the stock price returns, contains daily-sampled data from the beginning of 2003 until the end of 2008, containing 1555 trading days recorded. The aim of this paper is to investigate the tail exponent in tails of the distribution for blue chip stocks and penny stocks financial returns in six years period. By using a standard regression method, it is found that the distribution performed double scaling on the log-log plot of the cumulative probability of the normalized returns. Thus we calculate α for a small scale return as well as large scale return. Based on the result obtained, it is found that the power-law behavior for the probability density functions of the stock price absolute returns P(z)˜z-α with values lying inside and outside the Lévy stable regime with values α>2. All the results were discussed in detail.

  13. EIF4A2 is a positional candidate gene at the 3q27 locus linked to type 2 diabetes in French families

    DEFF Research Database (Denmark)

    Cheyssac, Claire; Dina, Christian; Leprêtre, Frédéric

    2006-01-01

    .01 at D3S3686, P = 0.0001) was identified in a set of French families. To assess genetic variation underlying both age-of-onset QTL and our previous type 2 diabetes linkage in a 3.87-Mb interval, we explored 36 single nucleotide polymorphisms (SNPs) in two biologically relevant candidate genes for glucose...... homeostasis, kininogen (KNG1), and eukaryotic translation initiation factor 4alpha2 (EIF4A2). Analysis of 148 families showed significant association of a frequent SNP, rs266714, located 2.47 kb upstream of EIF4A2, with familial type 2 diabetes (family-based association test, P = 0.0008) and early age......RNA translation and protein synthesis rate in pancreatic beta-cells, and our data indicates that EIF4A2 is downregulated by high glucose in rat beta-INS832/13 cells. The potential role of EIF4A2 in glucose homeostasis and its putative contribution to type 2 diabetes in the presence of metabolic stress...

  14. Facilitating Positive Psychosocial Adaptation in Children with Cystic Fibrosis by Increasing Family Communication and Problem-Solving Skills. A Research Report to the Cystic Fibrosis Foundation.

    Science.gov (United States)

    Stabler, Brian; And Others

    This study tested the effects of two group-oriented supportive and educational approaches on the parents of children with cystic fibrosis (CF). Thirteen families were randomly assigned either to a group which received information on medical and technical aspects of CF or to a group which received instruction in communication skills in addition to…

  15. Helping the Helpers: An International Training Program for Professionals Providing Social Services for HIV-Positive Children and Their Families in Southern Kazakhstan

    Science.gov (United States)

    Tartakovsky, Eugene

    2011-01-01

    Over one hundred children and some of their parents were infected with HIV in state hospitals in the Chimkent region in Southern Kazakhstan. After this tragedy, the Regional Department of Public Health organized social services for these families and asked the American Jewish Joint Distribution Committee (JDC) to provide them with training and…

  16. Military and Veteran Families and Children: Policies and Programs for Health Maintenance and Positive Development. Social Policy Report. Volume 28, Number 3

    Science.gov (United States)

    Cozza, Stephen J.; Lerner, Richard M.; Haskins, Ron

    2014-01-01

    This "Social Policy Report" summarizes what is currently known about our nation's military children and families and presents ideas and proposals pertinent to the formulation of new programs and the policies that would create and sustain these initiatives. We emphasize the need for future rigorous developmental research about military…

  17. Excess breast cancer risk in first degree relatives of CHEK2∗1100delC positive familial breast cancer cases

    NARCIS (Netherlands)

    Adank, Muriel A.; Verhoef, Senno; Oldenburg, Rogier A.; Schmidt, Marjanka K.; Hooning, Maartje J.; Martens, John W. M.; Broeks, Annegien; Rookus, Matti; Waisfisz, Quinten; Witte, Birgit I.; Jonker, Marianne A.; Meijers-Heijboer, Hanne

    2013-01-01

    The CHEK2∗1100delC mutation confers a relative risk of two for breast cancer (BC) in the general population. This study aims to explore the excess cancer risk due to the CHEK2∗1100delC mutation within a familial non-BRCA1/2 breast cancer setting. Cancer incidences were compared between first degree

  18. 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...

  19. 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…

  20. 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.

  1. 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

  2. The importance of a positive family history of alcoholism, parental rejection and emotional warmth, behavioral problems and peer substance use for alcohol problems in teenagers: a path analysis.

    Science.gov (United States)

    Barnow, Sven; Schuckit, Marc A; Lucht, Michael; John, Ulrich; Freyberger, Harald J

    2002-05-01

    The purpose of this study was to test a hypothetical model of alcohol problems in German adolescents. Among 180 offspring, family history of alcoholism, parenting styles, behavioral and emotional problems, peer-group characteristics, feelings of self-esteem, behavioral problems and psychiatric comorbidity of the parents were examined. Data were generated from the Study of Health in Pomerania (SHIP), in which families were randomly selected if 12-18 year old biological offspring were members of the household; a smaller group of subjects was selected from local outpatient treatment centers. Members of 133 families, including 180 (50.6% male) offspring who were appropriate for the current analyses, received personal semistructured diagnostic interviews and several self-rating questionnaires. Analyses compared offspring with alcohol problems (AP; n = 40) and with no alcohol problems (NAP; n = 140), and used structural equation modeling to test a hypothetical model. The comparisons revealed that the AP group had significantly more behavioral problems (e.g., aggression/delinquency), more perceived parental rejection and less emotional warmth, a higher amount of alcohol consumption, were more likely to associate with substance-using peers and more often received a diagnosis of conduct disorder or antisocial personality disorder. Whereas the family history of alcoholism did not differ significantly between groups, parents of offspring with an alcohol use disorder had significantly more additional diagnoses on DSM-IV Axis I. The evaluation of the model supported the importance of aggression/delinquency and association with substance-using peers for alcohol problems in people. An additional diagnosis in the parents was directly and indirectly (through aggression/delinquency) related to alcohol problems of the adolescents. The data indicate that alcohol problems in the offspring are associated with several domains of influence in their environment. Prospective studies

  3. Effect of noise and filtering on largest Lyapunov exponent of time series associated with human walking.

    Science.gov (United States)

    Mehdizadeh, Sina; Sanjari, Mohammad Ali

    2017-11-07

    This study aimed to determine the effect of added noise, filtering and time series length on the largest Lyapunov exponent (LyE) value calculated for time series obtained from a passive dynamic walker. The simplest passive dynamic walker model comprising of two massless legs connected by a frictionless hinge joint at the hip was adopted to generate walking time series. The generated time series was used to construct a state space with the embedding dimension of 3 and time delay of 100 samples. The LyE was calculated as the exponential rate of divergence of neighboring trajectories of the state space using Rosenstein's algorithm. To determine the effect of noise on LyE values, seven levels of Gaussian white noise (SNR=55-25dB with 5dB steps) were added to the time series. In addition, the filtering was performed using a range of cutoff frequencies from 3Hz to 19Hz with 2Hz steps. The LyE was calculated for both noise-free and noisy time series with different lengths of 6, 50, 100 and 150 strides. Results demonstrated a high percent error in the presence of noise for LyE. Therefore, these observations suggest that Rosenstein's algorithm might not perform well in the presence of added experimental noise. Furthermore, findings indicated that at least 50 walking strides are required to calculate LyE to account for the effect of noise. Finally, observations support that a conservative filtering of the time series with a high cutoff frequency might be more appropriate prior to calculating LyE. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Hurst Exponent Analysis of Resting-State fMRI Signal Complexity across the Adult Lifespan

    Directory of Open Access Journals (Sweden)

    Jianxin Dong

    2018-02-01

    Full Text Available Exploring functional information among various brain regions across time enables understanding of healthy aging process and holds great promise for age-related brain disease diagnosis. This paper proposed a method to explore fractal complexity of the resting-state functional magnetic resonance imaging (rs-fMRI signal in the human brain across the adult lifespan using Hurst exponent (HE. We took advantage of the examined rs-fMRI data from 116 adults 19 to 85 years of age (44.3 ± 19.4 years, 49 females from NKI/Rockland sample. Region-wise and voxel-wise analyses were performed to investigate the effects of age, gender, and their interaction on complexity. In region-wise analysis, we found that the healthy aging is accompanied by a loss of complexity in frontal and parietal lobe and increased complexity in insula, limbic, and temporal lobe. Meanwhile, differences in HE between genders were found to be significant in parietal lobe (p = 0.04, corrected. However, there was no interaction between gender and age. In voxel-wise analysis, the significant complexity decrease with aging was found in frontal and parietal lobe, and complexity increase was found in insula, limbic lobe, occipital lobe, and temporal lobe with aging. Meanwhile, differences in HE between genders were found to be significant in frontal, parietal, and limbic lobe. Furthermore, we found age and sex interaction in right parahippocampal gyrus (p = 0.04, corrected. Our findings reveal HE variations of the rs-fMRI signal across the human adult lifespan and show that HE may serve as a new parameter to assess healthy aging process.

  5. A Brainnetome Atlas Based Mild Cognitive Impairment Identification Using Hurst Exponent

    Directory of Open Access Journals (Sweden)

    Zhuqing Long

    2018-04-01

    Full Text Available Mild cognitive impairment (MCI, which generally represents the transition state between normal aging and the early changes related to Alzheimer’s disease (AD, has drawn increasing attention from neuroscientists due that efficient AD treatments need early initiation ahead of irreversible brain tissue damage. Thus effective MCI identification methods are desperately needed, which may be of great importance for the clinical intervention of AD. In this article, the range scaled analysis, which could effectively detect the temporal complexity of a time series, was utilized to calculate the Hurst exponent (HE of functional magnetic resonance imaging (fMRI data at a voxel level from 64 MCI patients and 60 healthy controls (HCs. Then the average HE values of each region of interest (ROI in brainnetome atlas were extracted and compared between MCI and HC. At last, the abnormal average HE values were adopted as the classification features for a proposed support vector machine (SVM based identification algorithm, and the classification performance was estimated with leave-one-out cross-validation (LOOCV. Our results indicated 83.1% accuracy, 82.8% sensitivity and 83.3% specificity, and an area under curve of 0.88, suggesting that the HE index could serve as an effective feature for the MCI identification. Furthermore, the abnormal HE brain regions in MCI were predominately involved in left middle frontal gyrus, right hippocampus, bilateral parahippocampal gyrus, bilateral amygdala, left cingulate gyrus, left insular gyrus, left fusiform gyrus, left superior parietal gyrus, left orbital gyrus and left basal ganglia.

  6. 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.

  7. Promoter of CaZF, a chickpea gene that positively regulates growth and stress tolerance, is activated by an AP2-family transcription factor CAP2.

    Directory of Open Access Journals (Sweden)

    Deepti Jain

    Full Text Available Plants respond to different forms of stresses by inducing transcription of a common and distinct set of genes by concerted actions of a cascade of transcription regulators. We previously reported that a gene, CaZF encoding a C2H2-zinc finger family protein from chickpea (Cicer arietinum imparted high salinity tolerance when expressed in tobacco plants. We report here that in addition to promoting tolerance against dehydration, salinity and high temperature, the CaZF overexpressing plants exhibited similar phenotype of growth and development like the plants overexpressing CAP2, encoding an AP2-family transcription factor from chickpea. To investigate any relationship between these two genes, we performed gene expression analysis in the overexpressing plants, promoter-reporter analysis and chromatin immunoprecipitation. A number of transcripts that exhibited enhanced accumulation upon expression of CAP2 or CaZF in tobacco plants were found common. Transient expression of CAP2 in chickpea leaves resulted in increased accumulation of CaZF transcript. Gel mobility shift and transient promoter-reporter assays suggested that CAP2 activates CaZF promoter by interacting with C-repeat elements (CRTs in CaZF promoter. Chromatin immunoprecipitation (ChIP assay demonstrated an in vivo interaction of CAP2 protein with CaZF promoter.

  8. 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.

  9. 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.

  10. 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.

  11. Using the Hurst's exponent as a monitor and predictor of BWR reactor instabilities

    International Nuclear Information System (INIS)

    Gavilan Moreno, Carlos J.

    2010-01-01

    Since the decade of the 1950s, when the development of boiling water reactor technology began, unstable situations have existed, which involve a high amplitude self-oscillatory process in the reactor's thermal power. As the development progressed and the reactors increased power density, the possibility of instability under certain circumstances increased. Thus, in 1985, Caorso nuclear plant (Italy) reported the first event of this type, and in 1988, such an event was reported at La Salle as well. Since then, multiple instability events have been reported. The danger of these unstable power situations resides in the possibility of exceeding a thermal limit, as expressed in Appendix A of 10FR50. Thus, the need arises to monitor and correct these situations in the industry. The most common way to monitor and control these instability situations involves the use of Decay Ratio (DR) and Resonance Frequency (RF). The use of these parameters is polemical, because their use involves certain simplifications and operations prior to the calculation which question how well they represent the reality. The most important simplifications are those which lead to the interpretation of the power time series as the result of a second order system. With regard to the previous operations, the time series needs to be standardized and filtered. The result is loss of information during prediction, due to the operations, and the results, therefore, lack accuracy. In this paper, the system is considered without simplifications, that is to say that it is treated as dynamic and, as we shall see, chaotic, in the mathematical sense of the term. The series will be used in pure form without manipulations. The parameter used for monitoring and prediction of the core's behaviour will be the Hurst's exponent (H). The concept used for this proposal is that the response of a complex dynamic system depends not only on the last excitation, but on the prior history. The processes and systems are

  12. 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'.

  13. 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...

  14. 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

  15. 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

  16. Disruption and analysis of the clpB, clpC, and clpE genes in Lactococcus lactis: ClpE, a new Clp family in gram-positive bacteria

    DEFF Research Database (Denmark)

    Ingmer, Hanne; Vogensen, Finn K.; Hammer, Karin

    1999-01-01

    In the genome of the gram-positive bacterium Lactococcus lactis MG1363, we have identified three genes (clpC, clpE, and clpB) which encode Clp proteins containing two conserved ATP binding domains. The proteins encoded by two of the genes belong to the previously described ClpB and ClpC families....... The clpE gene, however, encodes a member of a new Clp protein family that is characterized by a short N-terminal domain including a putative zinc binding domain (-CX2CX22CX2C-). Expression of the 83-kDa ClpE protein as well as of the two proteins encoded by clpB was strongly induced by heat shock and...... was shown to participate in the degradation of randomly folded proteins in L. lactis, could be necessary for degrading proteins generated by certain types of stress....

  17. Impact of somatic PI3K pathway and ERBB family mutations on pathological complete response (pCR) in HER2-positive breast cancer patients who received neoadjuvant HER2-targeted therapies.

    LENUS (Irish Health Repository)

    Toomey, Sinead

    2017-07-27

    The Cancer Genome Atlas analysis revealed that somatic EGFR, receptor tyrosine-protein kinase erbB-2 (ERBB2), Erb-B2 receptor tyrosine kinase 3 (ERBB3) and Erb-B2 receptor tyrosine kinase 4 (ERBB4) gene mutations (ERBB family mutations) occur alone or co-occur with somatic mutations in the gene encoding the phosphatidylinositol 3-kinase (PI3K) catalytic subunit (PIK3CA) in 19% of human epidermal growth factor receptor 2 (HER2)-positive breast cancers. Because ERBB family mutations can activate the PI3K\\/AKT pathway and likely have similar canonical signalling effects to PI3K pathway mutations, we investigated their combined impact on response to neoadjuvant HER2-targeted therapies.

  18. 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.

  19. 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.

  20. 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. 

  1. 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

  2. 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

  3. 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.

  4. 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…

  5. Origin of superconductivity in KFe2As2 under positive and negative pressures and relation to other Fe-based families

    Science.gov (United States)

    Valenti, Roser

    KFe2As2 shows an intricate behavior as a function of pressure. At ambient pressure the system is superconductor with a low critical temperature Tc=3.4 K and follows a V-shaped pressure dependence of Tc for moderate pressures with a local minimum at a pressure of 1.5 GPa. Under high pressures Pc=15 GPa, KFe2As2 exhibits a structural phase transition from a tetragonal to a collapsed tetragonal phase accompanied by a boost of the superconducting critical temperature up to 12 K. On the other hand, negative pressures realized through substitution of K by Cs or Rb decrease Tc down to 2.25K. In this talk we will discuss recent progress on the understanding of the microscopic origin of this pressure-dependent behavior by considering a combination of ab initio density functional theory with dynamical mean field theory and spin fluctuation theory calculations. We will argue that a Lifshitz transition associated with the structural collapse changes the pairing symmetry from d-wave (tetragonal) to s+/- (collapsed tetragonal) at high pressures while at ambient and negative pressures correlation effects appear to be detrimental for superconductivity. Further, we shall establish cross-links to the chalcogenide family, in particular FeSe under pressure. The Deutsche Forschungsgemeinschaft (DFG) is gratefully acknowledged for financial support.

  6. Positive Impact on Physical Activity and Health Behaviour Changes of a 15-Week Family Focused Intervention Program: “Juniors for Seniors”

    Directory of Open Access Journals (Sweden)

    Michał Bronikowski

    2016-01-01

    Full Text Available The promotion of physical activity (PA in children and their parents requires effective planning and sometimes even interventions. This study shows the effect of PA during a 15-week intervention program “Junior for Seniors” by applying a socioecological model to the interpretation of the data. This comprehensive approach emphasizes the fact that health promotion should focus not only on intrapersonal factors but also on the multilevel factors that might be determinants and modulators of increased PA. In 2015, 24 children (“juniors,” 14 girls and 10 boys, aged M=7.96±0.69 and 22 parents (“seniors,” 14 mothers aged M=38.86±2.96 and 8 fathers aged M=37.38±2.97 were voluntarily enrolled in a study spread across three primary schools in the city of Poznań, Poland. The effectiveness of the intervention was determined according to postintervention behavioural changes in PA in comparison to preintervention levels, as reported by the parents and children. Overall, the study found increases in PA levels and reductions in sedentary time. Although the changes are modest, there are some unrecognized benefits of the intervention which may have occurred, such as improved sport and motor skills, more frequent family social behaviours (walks, meals, and visiting relatives, or simply improved quality of “do-together” leisure time PA.

  7. Power spectral density and scaling exponent of high frequency global solar radiation sequences

    Science.gov (United States)

    Calif, Rudy; Schmitt, François G.; Huang, Yongxiang

    2013-04-01

    invariance: Iq(f) ~ f-?(q) , ?(q) is the scaling exponent. This allows to characterize the scaling behavior of a process: fractal or multifractal with intermittent properties. For q = 2, the Hilbert spectrum is defined. In this work, The data are collected at the University site of Guadeloupe, an island in the West Indies, located at 16°15 N latitude 60°30 W longitude. Our measurements sampled at 1 Hz were performed during one year period. The analyzed data present a power spectral density E(f) displaying a power law of the form E(f) ~ f-β with 1.6 ˜ β ˜ 2.2 for frequencies f ˜ 0.1 Hz, corresponding to time scales T × 10 s. Furthermore, global solar radiation data possesses multifractal properties. For comparison, other multifractal analysis techniques such as structure functions, MDFA, wavelet leaders are also used. This preliminary work set the basis for further investigation dedicated to simulate and forecast a sequence of solar energy fluctuation under different meteorological conditions, in the multifractal framework.

  8. 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...

  9. Crianças Sobredotadas, Posição da familia e comunidade no plano educativo / Gifted children development - Family and Community position

    Directory of Open Access Journals (Sweden)

    Zenita Guenther

    2017-12-01

    Full Text Available Crianças sobredotadas mostram desempenho notavelmente superior em relação ao grupo comparável, como indicação da maior capacidade de aprender. Sustentam esse processo: a Família, onde a criança nasce e é criada; a Escola, instituição social encarregada de prover educação; e a Comunidade, como o terreno onde forças culturais e ideológicas atuam, influenciando a vida das pessoas; portanto, a comunidade oferece as bases de um programa para desenvolver o potencial de suas crianças e jovens sobredotados. Ressaltam na comunidade 1º. A influência das instituições educacionais, mormente universidades, e 2º. A ação de pessoas ali reconhecidas e produtivas, sob a forma de voluntariado. O presente artigo discute maneiras como essas duas fontes podem ser recrutadas para atuar em um programa sistematizado de educação para desenvolver estudantes sobredotados e talentosos. Gifted children show significantly higher performance than their peers, what is an indication of their increased capacity to learn. Support this process: the family, where the child is born and raised; the School, a social institution in charge of providing education; and the community, where cultural and ideological forces act to influence people's lives; Therefore, the community offers basis for a program to develop the potential of their gifted children. The major forces within the community are: 1st. educational institutions, especially universities; and 2nd. voluntary action of acknowledged and productive persons. The present article discusses how these two sources can be recruited to act in a systematic program of education for gifted and talented students.Gifted; talent development; community talent centers

  10. Positive Effectiveness of Tafamidis in Delaying Disease Progression in Transthyretin Familial Amyloid Polyneuropathy up to 2 Years: An Analysis from the Transthyretin Amyloidosis Outcomes Survey (THAOS).

    Science.gov (United States)

    Mundayat, Rajiv; Stewart, Michelle; Alvir, Jose; Short, Sarah; Ong, Moh-Lim; Keohane, Denis; Rill, Denise; Sultan, Marla B

    2018-04-09

    The effectiveness of tafamidis for the treatment of transthyretin familial amyloid polyneuropathy (TTR-FAP) was evaluated using data from the Transthyretin Amyloidosis Outcomes Survey (THAOS) registry. Subjects receiving tafamidis (n = 252) were compared with untreated subjects in a non-randomized, matched cohort analysis. Subjects were matched with up to four untreated controls by genetic mutation, region of birth, and mean treatment propensity score. The matched, treated sample consisted predominantly of subjects with the Val30Met genotype (92.5%), from Portugal, and with a mean age of 40.4 years. Over the course of the 2-year follow-up period, subjects treated with tafamidis showed significantly less deterioration on the Neuropathy Impairment Score for Lower Limbs (p < 0.001) and its subscales (p < 0.023) compared with untreated subjects. There was significantly less deterioration among tafamidis-treated subjects compared with untreated subjects on the Norfolk Quality of Life scale (p < 0.001). There were no significant differences observed in functional (assessed by Karnofsky Performance Status Scale score) or nutritional (assessed by modified body mass index) status between the treated and untreated groups. The primary model which examined survival from baseline using the matched cohort was not able to yield estimates of the hazard ratio, as there were no deaths in the tafamidis-treated subjects. These findings support the results from clinical trials and strengthen evidence of the effectiveness of tafamidis beyond conventional clinical trials. ClinicalTrials.gov: NCT00628745 FUNDING: Pfizer.

  11. Associations of socioeconomic position in childhood and young adulthood with cardiometabolic risk factors: the Jerusalem Perinatal Family Follow-Up Study.

    Science.gov (United States)

    Savitsky, B; Manor, O; Friedlander, Y; Burger, A; Lawrence, G; Calderon-Margalit, R; Siscovick, D S; Enquobahrie, D A; Williams, M A; Hochner, H

    2017-01-01

    Several stages in the life course have been identified as important to the development of cardiovascular disease. This study aimed to assess the associations of childhood and adulthood socioeconomic position (SEP) and social mobility with cardiometabolic risk factors (CMRs) later in life. We conducted follow-up examinations of 1132 offspring, aged 32, within a population-based cohort of all births in Jerusalem from 1974 to 1976. SEP was indicated by parents' occupation and education, and adulthood SEP was based on offspring's occupation and education recorded at age 32. Linear regression models were used to investigate the associations of SEP and social mobility with CMRs. Childhood-occupational SEP was negatively associated with body mass index (BMI; β=-0.29, p=0.031), fat percentage (fat%; β=-0.58, p=0.005), insulin (β=-0.01, p=0.031), triglycerides (β=-0.02, p=0.024) and low-density lipoprotein cholesterol (LDL-C; β=-1.91, p=0.015), independent of adulthood SEP. Adulthood-occupational SEP was negatively associated with waist-to-hip ratio (WHR; β=-0.01, p=0.002), and positively with high-density lipoprotein cholesterol (HDL-C; β=0.87, p=0.030). Results remained similar after adjustment for smoking and inactivity. Childhood-educational SEP was associated with decreased WHR and LDL-C level (p=0.0002), and adulthood-educational SEP was inversely associated with BMI (p=0.001), waist circumference (p=0.008), WHR (p=0.001) and fat% (p=0.0002) and positively associated with HDL-C (p=0.030). Additionally, social mobility (mainly upward) was shown to have adverse cardiometabolic outcomes. Both childhood and adulthood SEP contribute independently to CMR. The match-mismatch hypothesis may explain the elevated CMRs among participants experiencing social mobility. Identification of life-course SEP-related aspects that translate into social inequality in cardiovascular risk may facilitate efforts for improving health and for reducing disparities in cardiovascular

  12. Quasilinear Elliptic Equations with Hardy-Sobolev Critical Exponents: Existence and Multiplicity of Nontrivial Solutions

    Directory of Open Access Journals (Sweden)

    Guanwei Chen

    2014-01-01

    Full Text Available We study the existence of positive solutions and multiplicity of nontrivial solutions for a class of quasilinear elliptic equations by using variational methods. Our obtained results extend some existing ones.

  13. Carbonyltrichlorotris(dimethylphenylphosphine)technetium-ethanol (1/1), the first seven-coordinate complex of technetium; position of this molecule in the Csub(3v) family

    Energy Technology Data Exchange (ETDEWEB)

    Bandoli, G; Clemente, D A; Mazzi, U [Consiglio Nazionale delle Ricerche, Padua (Italy). Lab. di Chimica e Tecnologia dei Radioelementi

    1978-01-01

    The preparation and the crystal and molecular structure of the title complex are reported. The coordination polyhedron is that of a distorted capped octahedron Csub(3v) symmetry). The technetium atom is seven-coordnate and bonded to three phosphine ligands (capped face), three chlorine ligands (uncapped face), and to the carbonyl group, which occupies the unique capping position. Crystals are monoclinic, space group P2/sub 1//c, with cell dimensions a = 11.732(9), b = 11.807(9), c = 23.588(12) A, and ..beta..103.42(8)/sup 0/. The structure has been refined by least squares to a conventional R of 0.093 for 1 794 observed reflections. Metal-ligand bond lengths are: Tc-CO 1.86(2), Tc-C1 2.48(1). and Tc-p 2.44(1) A. Seven coordinate complexes are briefly reviewed: in particular, a description of Csub(3v) symmetry and its distortions has been developed in terms of repulsion theory and the angular-overlap model.

  14. 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

  15. 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.

  16. 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.

  17. 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

  18. Associations of social environment, socioeconomic position and social mobility with immune response in young adults: the Jerusalem Perinatal Family Follow-Up Study.

    Science.gov (United States)

    Lawrence, Gabriella M; Friedlander, Yehiel; Calderon-Margalit, Ronit; Enquobahrie, Daniel A; Huang, Jonathan Yinhao; Tracy, Russell P; Manor, Orly; Siscovick, David S; Hochner, Hagit

    2017-12-21

    Immune response to cytomegalovirus (CMV) impacts adult chronic disease. This study investigates associations of childhood and adulthood social environment, socioeconomic position (SEP) and social mobility with CMV response in young adults. Historical prospective study design. Subcohort of all 17 003 births to residents of Jerusalem between 1974 and 1976. Participants included 1319 young adults born in Jerusalem with extensive archival and follow-up data, including childhood and adulthood SEP-related factors and anti-CMV IgG titre levels and seroprevalence measured at age 32. Principal component analysis was used to transform correlated social environment and SEP-related variables at two time points (childhood and adulthood) into two major scores reflecting household (eg, number of siblings/children, religiosity) and socioeconomic (eg, occupation, education) components. Based on these components, social mobility variables were created. Linear and Poisson regression models were used to investigate associations of components and mobility with anti-CMV IgG titre level and seroprevalence, adjusted for confounders. Lower levels of household and socioeconomic components in either childhood or adulthood were associated with higher anti-CMV IgG titre level and seropositivity at age 32. Compared with individuals with stable favourable components, anti-CMV IgG titre level and risk for seropositivity were higher in stable unfavourable household and socioeconomic components (household: β=3.23, P<0.001; relative risk (RR)=1.21, P<0.001; socioeconomic: β=2.20, P=0.001; RR=1.14, P=0.01), downward household mobility (β=4.32, P<0.001; RR=1.26, P<0.001) and upward socioeconomic mobility (β=1.37, P=0.04; RR=1.19, P<0.001). Among seropositive individuals, associations between household components and mobility with anti-CMV IgG titre level were maintained and associations between socioeconomic components and mobility with anti-CMV IgG titre level were attenuated. Our study

  19. Reducing stress and supporting positive relations in families of young children with type 1 diabetes: A randomized controlled study for evaluating the effects of the DELFIN parenting program

    Directory of Open Access Journals (Sweden)

    Saßmann Heike

    2012-09-01

    Full Text Available Abstract Background To assess initial efficacy and feasibility of a structured behavioural group training (DELFIN for parents of children with diabetes type 1, in order to reduce parenting stress and to improve parenting skills. Methods A randomized controlled study was conducted between July 2008 and September 2010, at a children’s hospital in Hannover with parents of children with type 1 diabetes (2–10 yrs (intervention group n = 37; control group n = 28. Parenting skills, parents’ psychological burden, children’s behavioural difficulties and quality of metabolic control were assessed before, 3 months after and 12 months after participating in the training program. Results In the intervention group parenting behaviour in conflict situations improved significantly after 3 months (Z = −3.28; p ≤ 0.001. It remained stable over 12 months (Z = −2.94; p ≤ 0.01. Depression and anxiety scores of parents decreased (Z = −1.93; p ≤ .05; Z = −2.02; p ≤ .05. Even though the outcome in the intervention group was more positive, the differences between both study arms failed to reach statistical significance. Unexpectedly parenting behaviour in the control group improved also (Z = −2.45; p ≤ .05. Anxiety as well as stress scores decreased in this group (Z = −2.02; p ≤ .05 and Z = −2.11; p ≤ .05. In both groups the initial metabolic control was good and without significant differences (A1c 7.2±0.8% vs. 7.1±0.4%; p > 0.5. It remained stable in the DELFIN group (A1c 7.1±0.8%; p > 0.5, but it increased slightly in controls (A1c 7.3±0.5%; Z = −2.79; p = .005. Conclusions This study has brought first evidence for the efficacy and feasibility of the program. A multicentre study with a larger sample is necessary to confirm these first results.

  20. 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.

  1. A POSITIVE SOCIALIZATION MODEL FOR CHILDREN WITH AUTISM SPECTRUM DISORDERS: COMPREHENSIVE AND INTERDISCIPLINARY APPROACHES. Part 2. Russian experience in social-psychological support of children with asd and their families

    Directory of Open Access Journals (Sweden)

    Albina A. Nesterova

    2016-01-01

    Full Text Available Abstract. The second part of the article aims to analyze domestic experience in support of children with autism; to show the complex model of support of positive socialization of children with ASD and severe defects; to justify the necessity of creating a scientifically validated complex model of support of children with ASD. Methods. The methods involve theoretical analysis and summarization of scientific and methodical publications on the issue of socialization of children with ASD; modeling method. Results. Scientific approaches to socialization and social integration of children with ASD are analyzed, summarized and systematized. The most efficient empirically validated methods and techniques that may be included in the process of social-psychological support of children with ASD and their families are indentified. Regional experience of the Russian Federation in solving the issue of socialization of children with ASD and their families is uncovered, the most effective programs and developments of domestic specialists are highlighted. The model of support of the positive socialization of children with ASD is developed and validated. Scientific novelty. The proposed model is developed on the basis of the principles of multidisciplinarity and interdisciplinarity in the process of interaction between specialists of support, aimed at solving socialization problems of children with ASD and their families. The model incorporates such basic conditions of positive socialization of a child with ASD as: a state of mental health of a child; creation of conditions for successful process of socialization of a child, in particular, for the formation of basic social skills; provision of close interaction of children, psychologists, teachers, parents, social partners; monitoring of dynamics of total indicators of social competence and development of children. Practical significance. The model is supposed to be the basis while creating support for

  2. 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.

  3. 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

  4. 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.

  5. A single amino acid substitution in the exoplasmic domain of the human growth hormone (GH) receptor confers familial GH resistance (Laron syndrome) with positive GH-binding activity by abolishing receptor homodimerization.

    Science.gov (United States)

    Duquesnoy, P; Sobrier, M L; Duriez, B; Dastot, F; Buchanan, C R; Savage, M O; Preece, M A; Craescu, C T; Blouquit, Y; Goossens, M

    1994-01-01

    Growth hormone (GH) elicits a variety of biological activities mainly mediated by the GH receptor (GHR), a transmembrane protein that, based on in vitro studies, seemed to function as a homodimer. To test this hypothesis directly, we investigated patients displaying the classic features of Laron syndrome (familial GH resistance characterized by severe dwarfism and metabolic dysfunction), except for the presence of normal binding activity of the plasma GH-binding protein, a molecule that derives from the exoplasmic-coding domain of the GHR gene. In two unrelated families, the same GHR mutation was identified, resulting in the substitution of a highly conserved aspartate residue by histidine at position 152 (D152H) of the exoplasmic domain, within the postulated interface sequence involved in homodimerization. The recombinant mutated receptor protein was correctly expressed at the plasma membrane. It displayed subnormal GH-binding activity, a finding in agreement with the X-ray crystal structure data inferring this aspartate residue outside the GH-binding domain. However, mAb-based studies suggested the critical role of aspartate 152 in the proper folding of the interface area. We show that a recombinant soluble form of the mutant receptor is unable to dimerize, the D152H substitution also preventing the formation of heterodimers of wild-type and mutant molecules. These results provide in vivo evidence that monomeric receptors are inactive and that receptor dimerization is involved in the primary signalling of the GH-associated growth-promoting and metabolic actions. Images PMID:8137822

  6. 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.

  7. Family Therapy

    Science.gov (United States)

    Family therapy Overview Family therapy is a type of psychological counseling (psychotherapy) that can help family members improve communication and resolve conflicts. Family therapy is usually provided by a psychologist, ...

  8. Dissolved families

    DEFF Research Database (Denmark)

    Christoffersen, Mogens

    The situation in the family preceding a family separation is studied here, to identify risk factors for family dissolution. Information registers covering prospective statistics about health aspects, demographic variables, family violence, self-destructive behaviour, unemployment, and the spousal...

  9. Family Checkup: Positive Parenting Prevents Drug Abuse

    Science.gov (United States)

    ... Alcohol Club Drugs Cocaine Fentanyl Hallucinogens Inhalants Heroin Marijuana MDMA (Ecstasy/Molly) Methamphetamine Opioids Over-the-Counter Medicines Prescription Medicines Steroids (Anabolic) Synthetic Cannabinoids (K2/Spice) Synthetic Cathinones (Bath Salts) Tobacco/ ...

  10. Physical Explanation of Archie's Porosity Exponent in Granular Materials: A Process-Based, Pore-Scale Numerical Study

    Science.gov (United States)

    Niu, Qifei; Zhang, Chi

    2018-02-01

    The empirical Archie's law has been widely used in geosciences and engineering to explain the measured electrical resistivity of many geological materials, but its physical basis has not been fully understood yet. In this study, we use a pore-scale numerical approach combining discrete element-finite difference methods to study Archie's porosity exponent m of granular materials over a wide porosity range. Numerical results reveal that at dilute states (e.g., porosity ϕ > 65%), m is exclusively related to the particle shape and orientation. As the porosity decreases, the electric flow in pore space concentrates progressively near particle contacts and m increases continuously in response to the intensified nonuniformity of the local electrical field. It is also found that the increase in m is universally correlated with the volume fraction of pore throats for all the samples regardless of their particle shapes, particle size range, and porosities.

  11. A Different Statistic for the Management of Portfolios - the Hurst Exponent: Persistent, Antipersistent or Random Time Series?

    Directory of Open Access Journals (Sweden)

    Ana-Maria CALOMFIR (METESCU

    2015-12-01

    Full Text Available In recent years, research in the capital markets and management of portfolios has been producing more questions than it has been answering: the need for a new paradigm or a new way of looking at things has become more and more concludent. The existing and classical view of capital markets, based on efficient market hypothesis, has a definite theory for the last six decades, but it is still not capable of significantly increase the understanding of how capital markets function. The purpose of this article is to theoretically describe a less used statistic coefficient, having a vast area of applicability due to its robustness, and which can easily divide the random series from a non-random series, even if the random series is non-Gaussian: the Hurst exponent.

  12. Evaluation of Cognitive Complexity of Tasks for the Topic Hydrogen Exponent in the Solutions of Acids and Bases

    Directory of Open Access Journals (Sweden)

    Saša Horvat

    2018-02-01

    Full Text Available The aim of this study was evaluation of cognitive complexity of tasks for the topic hydrogen exponent in the solutions of acids and bases and its validation. The created procedure included an assessment of the difficulty of concepts and an assessment of their interactivity. There were 48 freshmen students enrolled in the study program Basic academic studies in chemistry. As a research instrument for assessing performance, test of knowledge was specifically constructed for this research. Each task in the test was followed by a seven-point Likert scale for the evaluation of invested mental effort. The evaluation of cognitive complexity was confirmed by a series of linear regression analysis where high values of correlation coefficients are obtained among the examined variables: student’s performance and invested mental effort (dependent variables and cognitive complexity (independent variable.

  13. Parameter motivated mutual correlation analysis: Application to the study of currency exchange rates based on intermittency parameter and Hurst exponent

    Science.gov (United States)

    Cristescu, Constantin P.; Stan, Cristina; Scarlat, Eugen I.; Minea, Teofil; Cristescu, Cristina M.

    2012-04-01

    We present a novel method for the parameter oriented analysis of mutual correlation between independent time series or between equivalent structures such as ordered data sets. The proposed method is based on the sliding window technique, defines a new type of correlation measure and can be applied to time series from all domains of science and technology, experimental or simulated. A specific parameter that can characterize the time series is computed for each window and a cross correlation analysis is carried out on the set of values obtained for the time series under investigation. We apply this method to the study of some currency daily exchange rates from the point of view of the Hurst exponent and the intermittency parameter. Interesting correlation relationships are revealed and a tentative crisis prediction is presented.

  14. 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.

  15. 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.

  16. 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…

  17. [Impact of the positive appraisal of care on quality of life, purpose in life, and will to continue care among Japanese family caregivers of older adults: analysis by kinship type].

    Science.gov (United States)

    Yamamoto-Mitani, Noriko; Ishigaki, Kazuko; Kuniyoshi, Midori; Kawahara-Maekawa, Noriko; Hasegawa, Kiyomi; Hayashi, Kunihiko; Sugishita, Chieko

    2002-07-01

    The impact of positive appraisal of care (PAC) on the caregiver's quality of life (QL), sense of purpose in life (sense of ikigai) and will to continue care was examined. Data were collected from 322 Japanese family caregivers of older adults who were using visiting nursing services through 21 facilities in the Tokyo metropolitan area, and the prefectures of Shizuoka, Mie and Okinawa. The data were grouped by kinship type (husband or son, wife, daughter or daughter-in-law) and analyzed separately. From the multiple regression and logistic regression analyses, the following results were derived: 1) The PAC was not related to the physical QL regardless of the relationship type; 2) The relationship depended upon the relationship type: only the PAC was related to the mental QL among husband and son caregivers, both the PAC and the negative appraisal of care (NAC) were important among wives, only the NAC among daughters, and none of them among daughters-in-law; 3) Both the PAC and NAC were related to the sense of ikigai in all caregiver types except among husband and son caregivers, which showed no relationship between the NAC and sense of ikigai; 4) Both the PAC and NAC were related to will to continue care among son and husband caregivers, whereas only the PAC was among wives and daughters-in-law. Only the NAC was related among daughters. However, the difference across kinship type seems minimal for will to continue care. Understanding the PAC among family caregivers may be important in order to better assist them to improve their mental QL or sense of ikigai as well as to predict their continuation of caregiving at home. The impact of PAC varies depending on the kinship type, and it should be assessed separately with reference to this pariable to develop plans for appropriate assistance.

  18. 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.…

  19. Family Meals

    Science.gov (United States)

    ... Staying Safe Videos for Educators Search English Español Family Meals KidsHealth / For Parents / Family Meals What's in ... even more important as kids get older. Making Family Meals Happen It can be a big challenge ...

  20. Family Arguments

    Science.gov (United States)

    ... Spread the Word Shop AAP Find a Pediatrician Family Life Medical Home Family Dynamics Adoption & Foster Care ... Life Listen Español Text Size Email Print Share Family Arguments Page Content Article Body We seem to ...

  1. Family History

    Science.gov (United States)

    Your family history includes health information about you and your close relatives. Families have many factors in common, including their genes, ... as heart disease, stroke, and cancer. Having a family member with a disease raises your risk, but ...

  2. Family Issues

    Science.gov (United States)

    ... Some have two parents, while others have a single parent. Sometimes there is no parent and grandparents raise grandchildren. Some children live in foster families, adoptive families, or in stepfamilies. Families are much ...

  3. Family Disruptions

    Science.gov (United States)

    ... Spread the Word Shop AAP Find a Pediatrician Family Life Medical Home Family Dynamics Adoption & Foster Care ... Life Listen Español Text Size Email Print Share Family Disruptions Page Content Article Body No matter how ...

  4. Position Information

    Data.gov (United States)

    Social Security Administration — The Position Information Data Asset provides the ability to search for active SSA position descriptions using various search criteria. An individual may search by PD...

  5. 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…

  6. Positive Psychology

    Science.gov (United States)

    Peterson, Christopher

    2009-01-01

    Positive psychology is a deliberate correction to the focus of psychology on problems. Positive psychology does not deny the difficulties that people may experience but does suggest that sole attention to disorder leads to an incomplete view of the human condition. Positive psychologists concern themselves with four major topics: (1) positive…

  7. Ubiquitous positioning

    CERN Document Server

    Mannings, Robin

    2008-01-01

    This groundbreaking resource offers a practical, in-depth understanding of Ubiquitous Positioning - positioning systems that identify the location and position of people, vehicles and objects in time and space in the digitized networked economy. The future and growth of ubiquitous positioning will be fueled by the convergence of many other areas of technology, from mobile telematics, Internet technology, and location systems, to sensing systems, geographic information systems, and the semantic web. This first-of-its-kind volume explores ubiquitous positioning from a convergence perspective, of

  8. Contrasting predictability of summer monsoon rainfall ISOs over the northeastern and western Himalayan region: an application of Hurst exponent

    Science.gov (United States)

    Mukherjee, Sandipan

    2017-09-01

    Due to heterogeneous nonlinear forcing of complex geomorphological features, predictability of monsoon rainfall 10-90-day intra-seasonal oscillations (ISO) over the complex terrain of northeastern and western Himalayan region (NEH and WH) remained poorly quantified. Using 72 and 61 number of station observations of monsoon rainfall ISOs of NEH and WH, respectively, this study attempts to investigate variation in the regional scale predictability of monsoon rainfall ISOs with respect to changing geomorphological features and monsoon rainfall characteristics. In view of the bimodal nonlinear dynamical structure of monsoon rainfall ISO, the fractal dynamical Hurst exponent-based predictability indices are estimated as an indicator of predictability for station observations of NEH and WH, and relationships with elevations, slopes, aspects, and average numbers of occurrences of long (short) spell of active (break) phases are investigated. Results show 10-90-day ISOs are anti-persistent throughout the IHR, although, predictability of 10-90-day ISOs is higher over the NEH region than WH. Predictabilities of ISOs are found to decrease with increasing elevation and slope for both NEH and WH regions. Predictabilities of ISOs over both regions are also found to increase linearly as the number of occurrences of monsoon rainfall ISO phases (active/break) increases.

  9. Analysis of precipitation characteristics of South and North China based on the power-law tail exponents

    International Nuclear Information System (INIS)

    Feng Guolin; Zhang Daquan; Gong Zhiqiang; Zhi Rong

    2008-01-01

    Precipitation sequence is a typical nonlinear and chaotic observational series, and studies on precipitation forecasts are restricted to the use of traditional linear statistical methods, especially when analysing the regional characteristics of precipitation. In the context of 20 stations' daily precipitation series (from 1956 to 2000) in South China (SC) and North China (NC), we divide each precipitation series into many self-stationary segments by using the heuristic segmentation algorithm (briefly BG algorithm). For each station's precipitation series, we calculate the exponent of power-law tail (EPT) of the cumulative probability distribution of segments with a length larger than l for precipitation and temperature series. Our results show that the power-law decay of the cumulative probability distribution of stationary segments might be a common attribution for precipitation and other nonstationary time series; the EPT somewhat indicates the precipitation duration and its spatial distribution that might be different from area to area. The EPT in NC is larger than in SC; Meanwhile, EPT might be another effective way to study the abrupt changes in nonlinear and nonstationary time series. (geophysics, astronomy and astrophysics)

  10. Generalized Hurst exponent and multifractal function of original and translated texts mapped into frequency and length time series

    Science.gov (United States)

    Ausloos, M.

    2012-09-01

    A nonlinear dynamics approach can be used in order to quantify complexity in written texts. As a first step, a one-dimensional system is examined: two written texts by one author (Lewis Carroll) are considered, together with one translation into an artificial language (i.e., Esperanto) are mapped into time series. Their corresponding shuffled versions are used for obtaining a baseline. Two different one-dimensional time series are used here: one based on word lengths (LTS), the other on word frequencies (FTS). It is shown that the generalized Hurst exponent h(q) and the derived f(α) curves of the original and translated texts show marked differences. The original texts are far from giving a parabolic f(α) function, in contrast to the shuffled texts. Moreover, the Esperanto text has more extreme values. This suggests cascade model-like, with multiscale time-asymmetric features as finally written texts. A discussion of the difference and complementarity of mapping into a LTS or FTS is presented. The FTS f(α) curves are more opened than the LTS ones.

  11. Fractional Diffusion, Low Exponent Lévy Stable Laws, and 'Slow Motion' Denoising of Helium Ion Microscope Nanoscale Imagery.

    Science.gov (United States)

    Carasso, Alfred S; Vladár, András E

    2012-01-01

    Helium ion microscopes (HIM) are capable of acquiring images with better than 1 nm resolution, and HIM images are particularly rich in morphological surface details. However, such images are generally quite noisy. A major challenge is to denoise these images while preserving delicate surface information. This paper presents a powerful slow motion denoising technique, based on solving linear fractional diffusion equations forward in time. The method is easily implemented computationally, using fast Fourier transform (FFT) algorithms. When applied to actual HIM images, the method is found to reproduce the essential surface morphology of the sample with high fidelity. In contrast, such highly sophisticated methodologies as Curvelet Transform denoising, and Total Variation denoising using split Bregman iterations, are found to eliminate vital fine scale information, along with the noise. Image Lipschitz exponents are a useful image metrology tool for quantifying the fine structure content in an image. In this paper, this tool is applied to rank order the above three distinct denoising approaches, in terms of their texture preserving properties. In several denoising experiments on actual HIM images, it was found that fractional diffusion smoothing performed noticeably better than split Bregman TV, which in turn, performed slightly better than Curvelet denoising.

  12. Statistical mechanics of Roskilde liquids: configurational adiabats, specific heat contours, and density dependence of the scaling exponent.

    Science.gov (United States)

    Bailey, Nicholas P; Bøhling, Lasse; Veldhorst, Arno A; Schrøder, Thomas B; Dyre, Jeppe C

    2013-11-14

    We derive exact results for the rate of change of thermodynamic quantities, in particular, the configurational specific heat at constant volume, CV, along configurational adiabats (curves of constant excess entropy Sex). Such curves are designated isomorphs for so-called Roskilde liquids, in view of the invariance of various structural and dynamical quantities along them. The slope of the isomorphs in a double logarithmic representation of the density-temperature phase diagram, γ, can be interpreted as one third of an effective inverse power-law potential exponent. We show that in liquids where γ increases (decreases) with density, the contours of CV have smaller (larger) slope than configurational adiabats. We clarify also the connection between γ and the pair potential. A fluctuation formula for the slope of the CV-contours is derived. The theoretical results are supported with data from computer simulations of two systems, the Lennard-Jones fluid, and the Girifalco fluid. The sign of dγ∕dρ is thus a third key parameter in characterizing Roskilde liquids, after γ and the virial-potential energy correlation coefficient R. To go beyond isomorph theory we compare invariance of a dynamical quantity, the self-diffusion coefficient, along adiabats and CV-contours, finding it more invariant along adiabats.

  13. Adaptive inversion algorithm for 1 . 5 μm visibility lidar incorporating in situ Angstrom wavelength exponent

    Science.gov (United States)

    Shang, Xiang; Xia, Haiyun; Dou, Xiankang; Shangguan, Mingjia; Li, Manyi; Wang, Chong

    2018-07-01

    An eye-safe 1 . 5 μm visibility lidar is presented in this work considering in situ particle size distribution, which can be deployed in crowded places like airports. In such a case, the measured extinction coefficient at 1 . 5 μm should be converted to that at 0 . 55 μm for visibility retrieval. Although several models have been established since 1962, the accurate wavelength conversion remains a challenge. An adaptive inversion algorithm for 1 . 5 μm visibility lidar is proposed and demonstrated by using the in situ Angstrom wavelength exponent, which is derived from an aerosol spectrometer. The impact of the particle size distribution of atmospheric aerosols and the Rayleigh backscattering of atmospheric molecules are taken into account. Using the 1 . 5 μm visibility lidar, the visibility with a temporal resolution of 5 min is detected over 48 h in Hefei (31 . 83∘ N, 117 . 25∘ E). The average visibility error between the new method and a visibility sensor (Vaisala, PWD52) is 5.2% with the R-square value of 0.96, while the relative error between another reference visibility lidar at 532 nm and the visibility sensor is 6.7% with the R-square value of 0.91. All results agree with each other well, demonstrating the accuracy and stability of the algorithm.

  14. Phase transition in anisotropic holographic superfluids with arbitrary dynamical critical exponent z and hyperscaling violation factor α

    Energy Technology Data Exchange (ETDEWEB)

    Park, Miok [Korea Institute for Advanced Study, Seoul (Korea, Republic of); Park, Jiwon; Oh, Jae-Hyuk [Hanyang University, Department of Physics, Seoul (Korea, Republic of)

    2017-11-15

    Einstein-scalar-U(2) gauge field theory is considered in a spacetime characterized by α and z, which are the hyperscaling violation factor and the dynamical critical exponent, respectively. We consider a dual fluid system of such a gravity theory characterized by temperature T and chemical potential μ. It turns out that there is a superfluid phase transition where a vector order parameter appears which breaks SO(3) global rotation symmetry of the dual fluid system when the chemical potential becomes a certain critical value. To study this system for arbitrary z and α, we first apply Sturm-Liouville theory and estimate the upper bounds of the critical values of the chemical potential. We also employ a numerical method in the ranges of 1 ≤ z ≤ 4 and 0 ≤ α ≤ 4 to check if the Sturm-Liouville method correctly estimates the critical values of the chemical potential. It turns out that the two methods are agreed within 10 percent error ranges. Finally, we compute free energy density of the dual fluid by using its gravity dual and check if the system shows phase transition at the critical values of the chemical potential μ{sub c} for the given parameter region of α and z. Interestingly, it is observed that the anisotropic phase is more favored than the isotropic phase for relatively small values of z and α. However, for large values of z and α, the anisotropic phase is not favored. (orig.)

  15. Appropriateness of dynamical systems for the comparison of different embedding methods via calculation of the maximum Lyapunov exponent

    International Nuclear Information System (INIS)

    Franchi, M; Ricci, L

    2014-01-01

    The embedding of time series provides a valuable, and sometimes indispensable, tool in order to analyze the dynamical properties of a chaotic system. To this purpose, the choice of the embedding dimension and lag is decisive. The scientific literature describes several methods for selecting the most appropriate parameter pairs. Unfortunately, no conclusive criterion to decide which method – and thus which embedding pair – is the best has been so far devised. A widely employed quantity to compare different methods is the maximum Lyapunov exponent (MLE) because, for chaotic systems that have explicit analytic representations, MLE can be numerically evaluated independently of the embedding dimension and lag. Within this framework, we investigated the dependence on the calculated MLE on the embedding dimension and lag in the case of three dynamical systems that are also widespreadly used as reference systems, namely the Lorenz, Rössler and Mackey-Glass attractors. By also taking into account the statistical fluctuations of the calculated MLE, we propose a new method to assess which systems provide suitable test benches for the comparison of different embedding methods via MLE calculation. For example we found that, despite of its popularity in this scientific context, the Rössler attractor is not a reliable workbench to test the validity of an embedding method

  16. Robust driver heartbeat estimation: A q-Hurst exponent based automatic sensor change with interactive multi-model EKF.

    Science.gov (United States)

    Vrazic, Sacha

    2015-08-01

    Preventing car accidents by monitoring the driver's physiological parameters is of high importance. However, existing measurement methods are not robust to driver's body movements. In this paper, a system that estimates the heartbeat from the seat embedded piezoelectric sensors, and that is robust to strong body movements is presented. Multifractal q-Hurst exponents are used within a classifier to predict the most probable best sensor signal to be used in an Interactive Multi-Model Extended Kalman Filter pulsation estimation procedure. The car vibration noise is reduced using an autoregressive exogenous model to predict the noise on sensors. The performance of the proposed system was evaluated on real driving data up to 100 km/h and with slaloms at high speed. It is shown that this method improves by 36.7% the pulsation estimation under strong body movement compared to static sensor pulsation estimation and appears to provide reliable pulsation variability information for top-level analysis of drowsiness or other conditions.

  17. Family Privilege

    Science.gov (United States)

    Seita, John R.

    2014-01-01

    Family privilege is defined as "strengths and supports gained through primary caring relationships." A generation ago, the typical family included two parents and a bevy of kids living under one roof. Now, every variation of blended caregiving qualifies as family. But over the long arc of human history, a real family was a…

  18. Positioning consumption

    DEFF Research Database (Denmark)

    Halkier, Bente; Keller, Margit

    2014-01-01

    positionings emerges based on empirical examples of research in parent–children consumption. Positionings are flexible discursive fixations of the relationship between the performances of the practitioner, other practitioners, media discourse and consumption activities. The basic positioning types...... are the practice maintenance and the practice change position, with different sorts of adapting in between. Media discourse can become a resource for a resistant position against social control or for an appropriating position in favour of space for action. Regardless of the current relation to a particular media......This article analyses the ways in which media discourses become a part of contested consumption activities. We apply a positioning perspective with practice theory to focus on how practitioners relate to media discourse as a symbolic resource in their everyday practices. A typology of performance...

  19. 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…

  20. Family Violence and Family Physicians

    Science.gov (United States)

    Herbert, Carol P.

    1991-01-01

    The acronym IDEALS summarizes family physicians' obligations when violence is suspected: to identify family violence; document injuries; educate families and ensure safety for victims; access resources and coordinate care; co-operate in the legal process; and provide support for families. Failure to respond reflects personal and professional experience and attitudes, fear of legal involvement, and lack of knowledge. Risks of intervention include physician burnout, physician overfunctioning, escalation of violence, and family disruption. PMID:21228987