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Sample records for dynamics temperamental differences

  1. Cross-cultural Temperamental Differences in Infants, Children, and Adults in the United States of America and Finland

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    Gaias, Larissa M.; Gartstein, Maria A.; Fisher, Philip A.; Putnam, Samuel P.; Räikkönen, Katri; Komsi, Niina

    2012-01-01

    Cross-cultural differences in temperament were investigated between infants (n = 131, 84 Finns), children (n = 653, 427 Finns), and adults (n = 759, 538 Finns) from the United States of America and Finland. Participants from both cultures completed the Infant Behavior Questionnaire, Childhood Behavior Questionnaire, and the Adult Temperament Questionnaire. Across all ages, Americans received higher ratings on temperamental fearfulness than Finnish individuals, and also demonstrated higher levels of other negative affects at several time points. During infancy and adulthood, Finns tended to score higher on positive affect and elements of temperamental effortful control. Gender differences consistent with prior studies emerged cross-culturally, and were found to be more pronounced in the U.S. during childhood and in Finland during adulthood. PMID:22428997

  2. Cross-cultural temperamental differences in infants, children, and adults in the United States of America and Finland.

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    Gaias, Larissa M; Räikkönen, Katri; Komsi, Niina; Gartstein, Maria A; Fisher, Philip A; Putnam, Samuel P

    2012-04-01

    Cross-cultural differences in temperament were investigated between infants (n = 131, 84 Finns), children (n = 653, 427 Finns), and adults (n = 759, 538 Finns) from the United States of America and Finland. Participants from both cultures completed the Infant Behavior Questionnaire, Childhood Behavior Questionnaire and the Adult Temperament Questionnaire. Across all ages, Americans received higher ratings on temperamental fearfulness than Finnish individuals, and also demonstrated higher levels of other negative affects at several time points. During infancy and adulthood, Finns tended to score higher on positive affect and elements of temperamental effortful control. Gender differences consistent with prior studies emerged cross-culturally, and were found to be more pronounced in the US during childhood and in Finland during adulthood. © 2012 The Authors. Scandinavian Journal of Psychology © 2012 The Scandinavian Psychological Associations.

  3. Temperamental Traits Versus Individual Physical Fitness Components and a Physical Activity Level

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    Bernatowicz Dominik

    2015-06-01

    Full Text Available The main aim of the study was to examine whether relationships exist between particular temperamental traits within the concept of Regulative Theory of Temperament and components of physical fitness, that are most crucial for success in sport. The research involved 108 individuals including 63 men (age 21.1 ± 1.6 yrs and 45 women (age 20.7 ± 1.3 yrs. None of the respondents were professionally engaged in sport. Components of physical fitness included: aerobic capacity, strength, agility, static-dynamic balance and reaction time. The respondents also completed two questionnaires: the Formal Characteristics of Behaviour – Temperament Inventory and the International Physical Activity Questionnaire. The results indicate that the temperamental traits had average to poor correlations with the components of physical fitness, whereas more statistically significant correlations were observed in women. Negative correlations were obtained between emotional reactivity and agility, which was a result confirmed by previous research. All temperamental traits related with the energetic aspects of behaviour correlated with simple reaction time in women. Physical activity and aerobic capacity did not correlate with any of the studied traits. The results do not allow for any general conclusions to be drawn, but can serve as a reference point for future research on temperamental traits as delineated by Regulative Theory of Temperament and their relationship with the components of physical fitness.

  4. Do temperamentally shy children process emotion differently than nonshy children? Behavioral, psychophysiological, and gender differences in reticent preschoolers.

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    Theall-Honey, Laura A; Schmidt, Louis A

    2006-04-01

    We examined regional brain electrical activity (EEG), heart rate, and subjective responses at rest and during the presentation of videoclips designed to elicit a range of emotions (e.g., sadness, anger, happiness, fear) among a sample of healthy 4-year-old children selected for temperamental shyness. We found that shy children exhibited significantly greater relative right central EEG activation at rest and during the presentation of the fear-eliciting videoclip than nonshy children. Shy females displayed greater relative right mid-frontal EEG activation during the sad, happy, and fear videoclips than shy males who displayed greater relative left mid-frontal EEG activation. These results (1) suggest that recent frontal EEG activation/emotion models might be gender-specific and (2) appear to provide the first empirical evidence for recent theoretical notions linking the origins and maintenance of temperamental shyness in children to difficulty in regulating fear responses. Copyright (c) 2006 Wiley Periodicals, Inc.

  5. Temperamental traits may be associated with medical students’ specialty preferences – pilot study

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    Agnieszka Pawełczyk

    2010-06-01

    Full Text Available Objective: This study was aimed at checking a hypothesis about a possible correlation between medical students’ temperamental traits and specialty preferences. Material and methods: The study was carried out among 202 students of the 6th year at the Medical University of Łódź in academic year 2008/2009. The examined group consisted of 140 women (69% and 62 men (31%. The average age of the students included into the study was 24.7 years (range: 23-29. The subjects were asked to fill in a questionnaire on demographic variables and the Formal Characteristics of BehaviourTemperament Inventory (FCB-TI by Zawadzki and Strelau. Results: The students taking part in the study preferred specialties in internal diseases (22%, surgery (18% and paediatrics (11%. Two point five percent of the students were indecisive in the specialty choice, 26% preferred surgical specialty and 71% – non-surgical specialty. Differences in temperamental traits were indicated between the students preferring different specialties. Students preferring surgery scored higher than those preferring internal medicine in Endurance (p=0.0036, d=0.63 and Activity (p=0.0292, d=0.63. Significantly higher average values were observed within two temperamental traits: Briskness (p=0.0083, d=0.5 and Endurance (p=0.0070, d=0.49 in students preferring surgical specialties, as compared to those choosing non-surgical specialties. Conclusions: Students’ preferring different medical specialties differ in temperamental traits. They obtained different results on the scales of Briskness, Endurance and Activity. The obtained results may be useful in vocational guidance within the choice of medical specialty.

  6. Emotional eating and temperamental traits in Eating Disorders: A dimensional approach.

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    Rotella, Francesco; Mannucci, Edoardo; Gemignani, Sara; Lazzeretti, Lisa; Fioravanti, Giulia; Ricca, Valdo

    2018-03-23

    Growing evidence shows that temperamental features and emotional dysregulation are linked to Eating Disorders (EDs). Aim of this study was to explore the possible relationship between temperament and emotional eating (EE) from a dimensional standpoint, and the association of specific temperamental dimensions with overeating triggered by specific emotions. We enrolled 253 women with Anorexia Nervosa, Bulimia Nervosa and Binge Eating Disorder. Of those, 189 (74.7%), 73 (28.8%), and 80 (31.6%) reported binge eating, purging, or restrictive behaviors, respectively (the categories are not mutually exclusive). Participants completed the Emotional Eating Scale (EES), the Temperament and Character Inventory, the Eating Disorder Examination Questionnaire (EDE-Q) and the Symptom Checklist 90-Revised (SCL-90-R). Higher Persistence scores were found in the Restriction group, while the Binge group reported lower Persistence and higher Novelty Seeking scores. The Purge group showed lower Reward Dependence, Self Directedness and Cooperativeness scores. Patients with Purge also reported lower BMI and higher scores on EDE-Q restriction and eating concern subscales as well as higher scores for all SCL 90-R subscales. Patterns of association between temperamental traits and specific emotions were found in each group. Therefore, some temperamental features could be considered predictors of specific associations between emotions and the tendency to eat. Copyright © 2018. Published by Elsevier B.V.

  7. [Athletic performance, self-esteem and temperamental profile : Which relationship?].

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    Masmoudi, Jawaher; Trigui, Dorsa; Feki, Ines; Bâati, Imen; Jaoua, Abdelaziz

    2015-03-01

    Several authors emphasize the close relationship between self-esteem and athletic performance; such a relationship may raise the following question: by saying "strong" or "without any physical condition", is it a fair presentation of the individual's abilities or he reveals the most fundamental aspects of his personality, such as emotional temperament? To evaluate self-esteem, physical self and temperamental profile in a group of sportsmen, and to look for a relationship between these variables and athletic performance. We performed a cross-sectional, descriptive and analytic study in 80 young handball players of the "senior" category. We assessed self-esteem using the Rosenberg Self Esteem Scale, physical self-using the Physical Self-Inventory (PSI), and temperamental profile using the Temperament Evaluation of Memphis, Paris and San Diego Auto-questionnaire (TEMPS-A). Athletic performance was evaluated by the team coach by means of a score ranging from 1 to 10. High self-esteem was correlated to female gender (p=0.03), to an early start of physical activity (pself-esteem (pself-esteem (p=0.001). Good athletic performance was associated with hyperthymic (pself-esteem might help to achieve better athletic performance. In this intervention, the individual temperamental profile should be taken into account.

  8. Original article Temperamental variation in learned irrelevance in humans

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    Aleksandra Gruszka

    2015-07-01

    Full Text Available Background Learned irrelevance (LIRR represents one of the mechanisms of attentional set-shifting and refers to the inability to attend to, or to learn about, any aspect of a stimulus previously experienced as irrelevant. Although it has been extensively studied in the context of clinical populations, not much is known about LIRR effects in relation to normal variation in individual differences. The present study was designed to assess how temperamental factors may modulate LIRR. Participants and procedures Sixty-eight healthy volunteers performed a visual discrimination learning task modelled after Wisconsin Card Sorting Test. To test the susceptibility to learned irrelevance, participants were expected to shift their attention either to a dimension that prior to the extra-dimensional shift was completely irrelevant, or to a dimension that was previously partly correlated with reinforcement. Temperamental traits were assessed using the Formal Characteristics of Behaviour-Temperament Inventory (Zawadzki & Strelau, 1997. Intelligence level was stratified according to Raven’s Advanced Progressive Matrices (Raven, Raven, & Court, 2003. Results Low level of Briskness and high level of Perseverance were related to enhanced susceptibility to LIRR. High levels of Activity and Emotional Reactivity were related to the poorer performance on the extra-dimensional set-shifting. No effects of other temperament characteristics or intelligence on LIRR were observed. Conclusions The results confirm a strong variation in LIRR related to individual differences in temperament, which appears to be unrelated to DA function. Our results highlight the importance of considering individual differences in studies on cognitive control.

  9. Exploring the relation between childhood trauma, temperamental traits and mindfulness in borderline personality disorder.

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    Elices, Matilde; Pascual, Juan C; Carmona, Cristina; Martín-Blanco, Ana; Feliu-Soler, Albert; Ruiz, Elisabet; Gomà-I-Freixanet, Montserrat; Pérez, Víctor; Soler, Joaquim

    2015-07-29

    Deficits in mindfulness-related capacities have been described in borderline personality disorder (BPD). However, little research has been conducted to explore which factors could explain these deficits. This study assesses the relationship between temperamental traits and childhood maltreatment with mindfulness in BPD. A total of 100 individuals diagnosed with BPD participated in the study. Childhood maltreatment was assessed using the Childhood Trauma Questionnaire (CTQ-SF), temperamental traits were assessed using the Zuckerman-Khulman Personality Questionnaire (ZKPQ), and mindfulness capabilities were evaluated with the Five Facet Mindfulness Questionnaire (FFMQ). Hierarchical regression analyses were performed including only those CTQ-SF and ZKPQ subscales that showed simultaneous significant correlations with mindfulness facets. Results indicated that neuroticism and sexual abuse were predictors of acting with awareness; and neuroticism, impulsiveness and sexual abuse were significant predictors of non-judging. Temperamental traits did not have a moderator effect on the relationship between childhood sexual abuse and mindfulness facets. These results provide preliminary evidence for the effects of temperamental traits and childhood trauma on mindfulness capabilities in BPD individuals. Further studies are needed to better clarify the impact of childhood traumatic experiences on mindfulness capabilities and to determine the causal relations between these variables.

  10. Familial and Temperamental Risk Factors for Social Anxiety Disorder

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    Hirshfeld-Becker, Dina R.

    2010-01-01

    Social anxiety disorder (SAD) is a common disorder that can lead to significant impairment. In this chapter, the author provides background on the disorder and reviews hypothesized familial and temperamental risk factors. In particular, it highlights the Massachusetts General Hospital (MGH) Longitudinal Study of Children at Risk for Anxiety, now…

  11. Temperamental Influences on Risk-taking during Middle Childhood

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    Nyström, Beatrice

    2017-01-01

    This thesis concerns temperamental qualities and their influence on risk-taking behavior during middle childhood (7–11 years of age). Contemporary research generally agrees upon the notion that temperament constitutes two motivational systems, sensitive to punishment and reward respectively, together with a third system that is responsible for regulating the motivational systems. Risk-taking is generally regarded as the tendency to engage in potentially harmful or dangerous behaviors that at ...

  12. Temperamental traits and results of psychoaptitude tests in applicants to become a cadet officer in the Italian Navy.

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    Maremmani, Icro; Maremmani, Angelo Giovanni Icro; Leonardi, Annalisa; Rovai, Luca; Bacciardi, Silvia; Rugani, Fabio; Dell'Osso, Liliana; Akiskal, Kareen; Akiskal, S Hagop

    2013-09-05

    Consistently with the involvement of affective temperaments in professional choices, our research team is aiming to outline the temperamental profile of subjects who are applying to enter a military career in the Italian Armed Forces. In this study we aim to verify the importance of temperamental traits not only in choosing the military career as a profession, but also in passing or failing the entrance examinations. We compared the affective temperaments (evaluated by TEMPS-A[P]) of those applying to become a cadet officer in the Italian Navy, divided into various subgroups depending on whether they passed or failed the entrance examination at various levels (high school final test, medical (physical and psychiatric), mathematical examination and aptitude test). We also tested for correlations between grades received and temperamental scores. Higher scores for those with a hyperthymic and lower scores for those with a depressive, cyclothymic or irritable temperament characterized applicants taking medical exams and aptitude tests. Higher scores on the high school final test correlated with lower hyperthymic, cyclothymic and irritable temperament scores. No correlations were found between temperamental traits and mathematical examinations. Multivariate analysis stressed the negative impact of a cyclothymic temperament and the poor discriminant power of temperaments regarding medical and mathematical examinations, and aptitude tests. Conversely, temperaments showed good discriminant power as far as psychiatric examinations are concerned. Hyperthymic temperamental traits appear to be important not only in choosing a profession, but also in passing entrance examinations. Even so, affective temperaments (strong hyperthymic and weak cyclothymic, depressive and irritable traits) are the only successfully predictors of the outcome of psychiatric examinations and, to a lesser extent, medical examinations and aptitude tests. Achieving high school graduation and passing

  13. A New Approach to Measuring Individual Differences in Sensitivity to Facial Expressions: Influence of Temperamental Shyness and Sociability

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    Xiaoqing eGao

    2014-02-01

    Full Text Available To examine individual differences in adults’ sensitivity to facial expressions, we used a novel method that has proved revealing in studies of developmental change. Using static faces morphed to show different intensities of facial expressions, we calculated two measures: (1 the threshold to detect that a low intensity facial expression is different from neutral, and (2 accuracy in recognizing the specific facial expression in faces above the detection threshold. We conducted two experiments with young adult females varying in reported temperamental shyness and sociability - the former trait is known to influence the recognition of facial expressions during childhood. In both experiments, the measures had good split half reliability. Because shyness was significantly negatively correlated with sociability, we used partial correlations to examine the relation of each to sensitivity to facial expression. Sociability was negatively related to threshold to detect fear (Experiment 1 and to misidentify fear as another expression or happy expressions as fear (Experiment 2. Both patterns are consistent with hypervigilance by less sociable individuals. Shyness was positively related to misidentification of fear as another emotion (Experiment 2, a pattern consistent with a history of avoidance. We discuss the advantages and limitations of this new approach for studying individual differences in sensitivity to facial expression.

  14. Amygdala temporal dynamics: temperamental differences in the timing of amygdala response to familiar and novel faces

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    Shelton Richard C

    2009-12-01

    Full Text Available Abstract Background Inhibited temperament - the predisposition to respond to new people, places or things with wariness or avoidance behaviors - is associated with increased risk for social anxiety disorder and major depression. Although the magnitude of the amygdala's response to novelty has been identified as a neural substrate of inhibited temperament, there may also be differences in temporal dynamics (latency, duration, and peak. We hypothesized that persons with inhibited temperament would have faster responses to novel relative to familiar neutral faces compared to persons with uninhibited temperament. We used event-related functional magnetic resonance imaging to measure the temporal dynamics of the blood oxygen level dependent (BOLD response to both novel and familiar neutral faces in participants with inhibited or uninhibited temperament. Results Inhibited participants had faster amygdala responses to novel compared with familiar faces, and both longer and greater amygdala response to all faces. There were no differences in peak response. Conclusion Faster amygdala response to novelty may reflect a computational bias that leads to greater neophobic responses and represents a mechanism for the development of social anxiety.

  15. Executive Function and Temperamental Fear Concurrently Predict Deception in School-Aged Children

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    Babkirk, Sarah; Saunders, Lauren V.; Solomon, Beylul; Kessel, Ellen M.; Crossman, Angela; Gokhan, Nurper; Dennis, Tracy A.

    2015-01-01

    The decision to intentionally withhold truthful information, or deception, is a key component of moral development and may be a precursor to more serious anti-social tendencies. Two factors, executive function (EF) and temperamental fear are each thought to influence childhood deception. Few studies, however, have explored deception in relation to…

  16. Contributions of Child's Physiology and Maternal Behavior to Children's Trajectories of Temperamental Reactivity

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    Blandon, Alysia Y.; Calkins, Susan D.; Keane, Susan P.; O'brien, Marion

    2010-01-01

    Trajectories of children's temperamental reactivity (negative affectivity and surgency) were examined in a community sample of 370 children across the ages of 4 to 7 with hierarchical linear modeling. Children's physiological reactivity (respiratory sinus arrhythmia [RSA]), physiological regulation ([delta]RSA), and maternal parenting behavior…

  17. Temperamental correlates of disruptive behavior disorders in young children: preliminary findings.

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    Hirshfeld-Becker, Dina R; Biederman, Joseph; Faraone, Stephen V; Violette, Heather; Wrightsman, Jessica; Rosenbaum, Jerrold F

    2002-04-01

    Our objective was to test the hypothesis that temperamental behavioral disinhibition measured in early childhood would be associated with disruptive behavior disorders. We used variables from laboratory-based behavioral observations originally devised to assess behavioral inhibition to construct a theory-based a priori definition of "behavioral disinhibition" in 200 young children at-risk for panic disorder, depression, or both and 84 children of parents without anxiety or major depressive disorder. We then compared behaviorally disinhibited and nonbehaviorally disinhibited children on rates of DSM-III-R disorders and measures of academic and social dysfunction. Behavioral disinhibition was significantly associated with higher rates of disruptive behavior disorders and mood disorders. Children with behavioral disinhibition were significantly more likely than nondisinhibited, noninhibited children to have attention-deficit/hyperactivity disorder (ADHD) and to have comorbid mood and disruptive behavior disorders. Moreover, disinhibited children had lower Global Assessment of Functioning Scale scores and were more likely to have been in special classes and to have problems with school behavior and leisure activities. These results suggest that behavioral disinhibition may represent a temperamental precursor to disruptive behavior problems, particularly ADHD. Longitudinal studies using behavioral assessments of behavioral disinhibition are needed to confirm these findings.

  18. The relationship between temperamental traits and the level of performance of an eye-hand co-ordination task in jet pilots.

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    Biernacki, Marcin; Tarnowski, Adam

    2008-01-01

    When assessing the psychological suitability for the profession of a pilot, it is important to consider personality traits and psychomotor abilities. Our study aimed at estimating the role of temperamental traits as components of pilots' personality in eye-hand co-ordination. The assumption was that differences in the escalation of the level of temperamental traits, as measured with the Formal Characteristic of Behaviour-Temperament Inventory (FCB-TI), will significantly influence eye-hand co-ordination. At the level of general scores, enhanced briskness proved to be the most important trait for eye-hand co-ordination. An analysis of partial scores additionally underlined the importance of sensory sensitivity, endurance and activity. The application of eye-hand co-ordination tasks, which involve energetic and temporal dimensions of performance, helped to disclose the role of biologically-based personality traits in psychomotor performance. The implication of these findings for selecting pilots is discussed.

  19. Maternal Caregiving Moderates the Relation between Temperamental Fear and Social Behavior with Peers

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    Penela, Elizabeth C.; Henderson, Heather A.; Hane, Amie A.; Ghera, Melissa M.; Fox, Nathan A.

    2012-01-01

    Temperament works in combination with a child's environment to influence early socioemotional development. We examined whether maternal caregiving behavior at infant age 9 months moderated the relation between infant temperamental fear (9 months) and observations of children's social behavior with an unfamiliar peer at age 2 in a typically…

  20. Temperamental, Parental, and Contextual Contributors to Early-Emerging Internalizing Problems: A New Integrative Analysis Approach

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    Mills, Rosemary S. L.; Hastings, Paul D.; Helm, Jonathan; Serbin, Lisa A.; Etezadi, Jamshid; Stack, Dale M.; Schwartzman, Alex E.; Li, Hai Hong

    2012-01-01

    This study evaluated a comprehensive model of factors associated with internalizing problems (IP) in early childhood, hypothesizing direct, mediated, and moderated pathways linking child temperamental inhibition, maternal overcontrol and rejection, and contextual stressors to IP. In a novel approach, three samples were integrated to form a large…

  1. Temperamental reactivity and negative emotionality in uncooperative children referred to specialized paediatric dentistry compared to children in ordinary dental care.

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    Arnrup, Kristina; Broberg, Anders G; Berggren, Ulf; Bodin, Lennart

    2007-11-01

    Current treatment of children with dental behaviour management problems (DBMP) is based on the presupposition that their difficulties are caused by dental fear, but is this always the case? The aim of this study was to study temperamental reactivity, negative emotionality, and other personal characteristics in relation to DBMP in 8- to 12-year-old children. Forty-six children referred because of DBMP (study group) and 110 children in ordinary dental care (reference group) participated. The EASI tempramental survey assessed temperamental reactivity and negative emotionality, the Child Behaviour Questionnaire internalizing and externalizing behaviour problems, and the Children's Fear Survey Schedule general and dental fears. Cluster analyses and tree-based modelling were used for data analysis. Among the five clusters identified, one could be characterized as 'balanced temperament'. Thirty-five per cent of the reference group compared to only 7% of the study group belonged to this cluster. Negative emotionality was the most important sorting variable. Children referred because of DBMP differed from children in ordinary dental care, not only in dental fear level, but also in personal characteristics. Few of the referred children were characterized by a balanced temperament profile. It is important to consider the dual impact of emotion dysregulation and emotional reactivity in the development of DBMP.

  2. Physiological reactions of preschoolers to fear-inducing film clips: Effects of temperamental fearfulness and quality of the parent-child relationship

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    Gelissen, R.; Koolstra, C.M.; van IJzendoorn, M.H.; Bakermans-Kranenburg, M.J.; van der Veer, R.

    2007-01-01

    This study investigates young children's fright reactions induced by television. The central question concerns the degree to which the impact can be predicted by temperamental fearfulness and the quality of the parent-child relationship. Using a procedure for recording simultaneously skin

  3. A Transactional Model of Temperamental Development: Evidence of a Relationship between Child Temperament and Maternal Stress over Five Years

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    Pesonen, Anu-Katriina; Raikkonen, Katri; Heinonen, Kati; Komsi, Niina; Jarvenpaa, Anna-Liisa; Strandberg, Timo

    2008-01-01

    Although there is growing consensus that parental stress is a risk factor in child development, longitudinal studies of its effects are few. This study tested a sample of 231 mother-child dyads in terms of whether the relations between the global experience of stress in mothers (perceived stress scale) and child temperamental characteristics…

  4. Effects of prenatal and postnatal maternal emotional stress on toddlers' cognitive and temperamental development.

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    Lin, Yanfen; Xu, Jian; Huang, Jun; Jia, Yinan; Zhang, Jinsong; Yan, Chonghuai; Zhang, Jun

    2017-01-01

    Maternal stress is associated with impairments in the neurodevelopment of offspring; however, the effects of the timing of exposure to maternal stress on a child's neurodevelopment are unclear. In 2010, we studied 225 mother-child pairs in Shanghai, recruiting mothers in mid-to-late pregnancy and monitoring offspring from birth until 30 months of age. Maternal stress was assessed prenatally (at 28-36 weeks of gestation) and postnatally (at 24-30 months postpartum) using the Symptom-Checklist-90-Revised Scale (SCL-90-R) and Life-Event-Stress Scale to evaluate mothers' emotional stress and life event stress levels, respectively. Children's cognition and temperament were assessed at 24-30 months of age using the Gesell Development Scale and Toddler Temperament Scale, respectively. Multi-variable linear regression models were used to associate prenatal and postnatal stress with child cognitive and temperamental development. Maternal prenatal and postnatal Global Severity Index (GSI) of SCL-90-R were moderately correlated (ICC r=0.30, Ptoddlers' gross motor, fine motor, adaptive and social behavior development independently of postnatal GSI, while the increase in postnatal GSI was associated with changes in multiple temperament dimensions independently of prenatal GSI. The effects of prenatal and postnatal depression scores of SCL-90-R were similar to those of GSI. Relatively small sample size. Compared with postnatal exposure, children's cognitive development may be more susceptible to prenatal exposure to maternal emotional stress, whereas temperamental development may be more affected by postnatal exposure to maternal emotional stress compared with prenatal exposure. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Anxiety and depression among adolescents with attention-deficit/hyperactivity disorder: The roles of behavioral temperamental traits, comorbid autism spectrum disorder, and bullying involvement

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    Huei-Fan Hu

    2016-02-01

    Full Text Available The aim of this study was to examine the associations of behavioral temperamental traits, comorbid autism spectrum disorder (ASD, and bullying involvement with anxiety and depression among adolescents with attention-deficit/hyperactivity disorder (ADHD in Taiwan. A total of 287 adolescents aged 11–18 years diagnosed with ADHD participated in this study. Their severities of anxiety and depression were assessed. Multiple regression analysis was used to examine the correlates of anxiety and depression. The results show that adolescents with ADHD who reported a higher behavioral inhibition system (BIS score, had comorbid ASD, and were bullying victims, reported more severe anxiety and depressive symptoms. Adolescents with ADHD who bullied others reported more severe depressive symptoms than those who did not bully. The results of this study indicated that behavioral temperamental traits on the BIS, comorbid ASD, and bullying involvement were significantly associated with anxiety and depression among the adolescents with ADHD.

  6. Child Temperamental Flexibility Moderates the Relation between Positive Parenting and Adolescent Adjustment

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    Rabinowitz, Jill A.; Drabick, Deborah A.G.; Reynolds, Maureen D.; Clark, Duncan B.; Olino, Thomas M.

    2016-01-01

    Temperamental flexibility and lower positive parenting are associated with internalizing and externalizing problems; however, youth varying in flexibility may be differentially affected by positive parenting in the prediction of symptoms. We examined whether children's flexibility moderated prospective relations between maternal and paternal positive parenting and youth internalizing and externalizing symptoms during adolescence. Participants (N =775, 71% male) and their caregivers completed measures when youth were 10-12 and 12-14 years old. Father positive parenting interacted with child flexibility to predict father-reported internalizing and externalizing problems. Consistent with the diathesis-stress model, children lower in flexibility experienced greater symptoms than children higher in flexibility in lower positive parenting contexts. Among children lower in flexibility, lower paternal positive parenting was associated with greater internalizing and externalizing symptoms compared to higher paternal positive parenting. However, among youth higher in flexibility, symptom levels were similar regardless of whether youth experienced lower or higher paternal positive parenting. PMID:26834305

  7. Early developmental, temperamental and educational problems in 'substance use disorder' patients with and without ADHD. Does ADHD make a difference?

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    Skutle, Arvid; Bu, Eli Torild Hellandsjø; Jellestad, Finn Konow; van Emmerik-van Oortmerssen, Katelijne; Dom, Geert; Verspreet, Sofie; Carpentier, Pieter Jan; Ramos-Quiroga, Josep Antoni; Franck, Johan; Konstenius, Maija; Kaye, Sharlene; Demetrovics, Zsolt; Barta, Csaba; Fatséas, Melina; Auriacombe, Marc; Johnson, Brian; Faraone, Stephen V; Levin, Frances R; Allsop, Steve; Carruthers, Susan; Schoevers, Robert A; Koeter, Maarten W J; van den Brink, Wim; Moggi, Franz; Møller, Merete; van de Glind, Geurt

    2015-12-01

    The prevalence of ADHD among patients with substance use disorder (SUD) is substantial. This study addressed the following research questions: Are early developmental, temperamental and educational problems overrepresented among SUD patients with ADHD compared to SUD patients without ADHD? Do this comorbid group receive early help for their ADHD, and are there signs of self-medicating with illicit central stimulants? An international, multi-centre cross-sectional study was carried out involving seven European countries, with 1205 patients in treatment for SUD. The mean age was 40 years and 27% of the sample was female. All participants were interviewed with the Mini International Neuropsychiatric Interview Plus and the Conners' Adult ADHD Diagnostic Interview for DSM-IV. SUD patients with ADHD ( n  = 196; 16.3% of the total sample) had a significantly slower infant development than SUD patients without ADHD ( n  = 1,009; 83.4%), had greater problems controlling their temperament, and had lower educational attainment. Only 24 (12%) of the current ADHD positive patients had been diagnosed and treated during childhood and/or adolescence. Finally, SUD patients with ADHD were more likely to have central stimulants or cannabis as their primary substance of abuse, whereas alcohol use was more likely to be the primary substance of abuse in SUD patients without ADHD. The results emphasize the importance of early identification of ADHD and targeted interventions in the health and school system, as well as in the addiction field.

  8. The Differential role of parenting, peers, and temperament for explaining interindividual differences in 18-months-olds' comforting and helping.

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    Schuhmacher, Nils; Collard, Jenny; Kärtner, Joscha

    2017-02-01

    This study analyzes temperamental and social correlates of 18-month-olds' (N=58) instrumental helping (i.e., handing over out-of-reach objects) and comforting (i.e., alleviating experimenter's distress). While out-of-reach helping as a basic type of prosocial behavior was not associated with any of the social and temperamental variables, comforting was associated with maternal responsible parenting, day care attendance, and temperamental fear, accounting for 34% of the total variance in a corresponding regression model. The data of the present study suggest that, while simple instrumental helping seems to be a robust developmental phenomenon, comforting is associated with specific social experiences and child temperament that constitute interindividual differences and thereby help to explain the domain-specific development of prosociality. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Brain functional connectivity changes in children that differ in impulsivity temperamental trait

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    Alberto eInuggi

    2014-05-01

    Full Text Available Impulsivity is a core personality trait forming part of normal behavior and contributing to adaptive functioning. However, in typically developing children, altered patterns of impulsivity constitute a risk factor for the development of behavioral problems. Since both pathological and non-pathological states are commonly characterized by continuous transitions, we used a correlative approach to investigate the potential link between personality and brain dynamics. We related brain functional connectivity of typically developing children, measured with magnetic resonance imaging at rest, with their impulsivity scores obtained from a questionnaire completed by their parents. We first looked for areas within the default mode network (DMN whose functional connectivity might be modulated by trait impulsivity. Then, we calculated the functional connectivity among these regions and the rest of the brain in order to assess if impulsivity trait altered their relationships. We found two DMN clusters located at the posterior cingulate cortex and the right angular gyrus which were negatively correlated with impulsivity scores. The whole-brain correlation analysis revealed the classic network of correlating and anti-correlating areas with respect to the DMN. The impulsivity trait modulated such pattern showing that the canonical anti-phasic relation between DMN and action-related network was reduced in high impulsive children. These results represent the first evidence that the impulsivity, measured as personality trait assessed through parents’ report, exerts a modulatory influence over the functional connectivity of resting state brain networks in typically developing children. The present study goes further to connect developmental approaches, mainly based on data collected through the use of questionnaires, and behavioral neuroscience, interested in how differences in brain structure and functions reflect in differences in behavior.

  10. Brain functional connectivity changes in children that differ in impulsivity temperamental trait.

    Science.gov (United States)

    Inuggi, Alberto; Sanz-Arigita, Ernesto; González-Salinas, Carmen; Valero-García, Ana V; García-Santos, Jose M; Fuentes, Luis J

    2014-01-01

    Impulsivity is a core personality trait forming part of normal behavior and contributing to adaptive functioning. However, in typically developing children, altered patterns of impulsivity constitute a risk factor for the development of behavioral problems. Since both pathological and non-pathological states are commonly characterized by continuous transitions, we used a correlative approach to investigate the potential link between personality and brain dynamics. We related brain functional connectivity of typically developing children, measured with magnetic resonance imaging at rest, with their impulsivity scores obtained from a questionnaire completed by their parents. We first looked for areas within the default mode network (DMN) whose functional connectivity might be modulated by trait impulsivity. Then, we calculated the functional connectivity among these regions and the rest of the brain in order to assess if impulsivity trait altered their relationships. We found two DMN clusters located at the posterior cingulate cortex and the right angular gyrus which were negatively correlated with impulsivity scores. The whole-brain correlation analysis revealed the classic network of correlating and anti-correlating areas with respect to the DMN. The impulsivity trait modulated such pattern showing that the canonical anti-phasic relation between DMN and action-related network was reduced in high impulsive children. These results represent the first evidence that the impulsivity, measured as personality trait assessed through parents' report, exerts a modulatory influence over the functional connectivity of resting state brain networks in typically developing children. The present study goes further to connect developmental approaches, mainly based on data collected through the use of questionnaires, and behavioral neuroscience, interested in how differences in brain structure and functions reflect in differences in behavior.

  11. Development of temperamental effortful control mediates the relationship between maturation of the prefrontal cortex and psychopathology during adolescence: A 4-year longitudinal study

    Directory of Open Access Journals (Sweden)

    Nandita Vijayakumar

    2014-07-01

    Full Text Available This study investigated the relationship between the development of effortful control (EC, a temperamental measure of self-regulation, and concurrent development of three regions of the prefrontal cortex (anterior cingulate cortex, ACC; dorsolateral prefrontal cortex, dlPFC; ventrolateral prefrontal cortex, vlPFC between early- and mid-adolescence. It also examined whether development of EC mediated the relationship between cortical maturation and emotional and behavioral symptoms. Ninety-two adolescents underwent baseline assessments when they were approximately 12 years old and follow-up assessments approximately 4 years later. At each assessment, participants had MRI scans and completed the Early Adolescent Temperament Questionnaire-Revised, as well as measures of depressive and anxious symptoms, and aggressive and risk taking behavior. Cortical thicknesses of the ACC, dlPFC and vlPFC, estimated using the FreeSurfer software, were found to decrease over time. EC also decreased over time in females. Greater thinning of the left ACC was associated with less reduction in EC. Furthermore, change in effortful control mediated the relationship between greater thinning of the left ACC and improvements in socioemotional functioning, including reductions in psychopathological symptoms. These findings highlight the dynamic association between EC and the maturation of the anterior cingulate cortex, and the importance of this relationship for socioemotional functioning during adolescence.

  12. Temperamental dimensions of the TEMPS-A in females with co-morbid bipolar disorder and bulimia.

    Science.gov (United States)

    Rybakowski, Janusz K; Kaminska, Katarzyna; Charytonik, Jolanta; Akiskal, Kareen K; Akiskal, Hagop S

    2014-08-01

    We investigated the effect of co-morbid bipolar disorder and bulimia on temperamental dimensions measured by TEMPS-A, relative to "pure" bulimia and "pure" bipolar disorder, in female patients. The study was performed on 47 patients with bipolar disorder (BD) with a mean age of 36±10 years, 96 patients with bulimia or bulimic type of anorexia, mean age 26±9 years and 50 control healthy females (HC), mean age 29±6 years. Among bulimic patients, a group of 68 subjects with co-morbid bulimia with bipolarity (BD+B) was identified, based on positive score of the Mood Disorder Questionnaire (MDQ). The TEMPS-A questionnaire, 110 questions version, has been used, evaluating five temperament domains: depressive, cyclothymic, hyperthymic, irritable and anxious. Parametric analysis was performed for 4 groups (BD, "pure" bulimia (PB), BD+B and HC), with 28 subjects randomly chosen from each group, using analysis of variance and cluster analysis. All clinical groups significantly differed from control group by having higher scores of depressive, cyclothymic, irritable and anxious temperaments and lower of hyperthymic one. Among patients, significantly higher scores of cyclothymic and irritable temperaments were found in BD+B compared to both PB and BD. These differences were also reflected in cluster analysis, where two clusters were identified. Bipolarity in bulimic patients assessed only by the MDQ. These results show that co-morbid bulimia and bipolar disorder is characterized by extreme dimensions of both cyclothymic and irritable temperaments, significantly higher than each single diagnosis. Possible clinical implications of such fact are discussed. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Assimilation and Individual Differences in Emotion: The Dynamics of Anger and Approach Motivation.

    Science.gov (United States)

    Lechuga, Julia; Fernandez, Norma P

    2011-03-01

    Individuals who cross cultural boundaries face many challenges when trying to adapt to a receiving culture. Adaptation challenges such as learning to maneuver across societal domains may become increasingly complex if structural level factors such as discrimination are present. Researchers have conceptualized acculturation as a relatively autonomous decision indicating that four acculturation strategies exist: assimilation, separation, integration, and marginalization. Moreover, researchers have also long debated the link between acculturation strategy, adaptation hassles and negative health outcomes. However, models seeking to explain how individual difference and structural level variables may influence each other and subsequently influence acculturation and adaptation are needed. The purpose of this study is to lay the foundation for the conceptualization of such a model. We propose that temperamental predispositions to negative emotionality, anger, and impulsivity may highlight discrimination which in turn may lead to increases in acculturative stress and negative markers of psychosocial well-being. We used SEM to test our hypothesized model. Results supported a modified model. Implications for the measurement of adaptation and interventions are discussed.

  14. Temperamental workers: Psychology, business, and the Humm-Wadsworth Temperament Scale in interwar America.

    Science.gov (United States)

    Lussier, Kira

    2018-05-01

    This article traces the history of a popular interwar psychological test, the Humm-Wadsworth Temperament Scale (HWTS), from its development in the early 1930s to its adoption by corporate personnel departments. In popular articles, trade magazines, and academic journals, industrial psychologist Doncaster Humm and personnel manager Guy Wadsworth trumpeted their scale as a scientific measure of temperament that could ensure efficient hiring practices and harmonious labor relations by screening out "problem employees" and screening for temperamentally "normal" workers. This article demonstrates how concerns about the epistemological and scientific credibility of the HWTS were intimately entangled with concerns about its value to business at every step in the test's development. The HWTS sought to measure the emotional and social dimensions of an individual's personality so as to assess their suitability for work. The practice of temperament testing conjured a vision of the subject whose emotional and social disposition was foundational to their own capacity to find employment, and whose capacity to appropriately express, but regulate, their emotions was foundational to corporate order. The history of the HWTS offers an instructive case of how psychological tests embed social hierarchies, political claims, and economic ideals within their very theoretical and methodological foundations. Although the HWTS itself may have faded from use, the test directly inspired creators of subsequent popular personality tests, such as the Minnesota Multiphasic Personality Inventory and the Myers-Briggs Type Indicator. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  15. Sex differences in psychological adjustment from infancy to 8 years.

    Science.gov (United States)

    Prior, M; Smart, D; Sanson, A; Oberklaid, F

    1993-03-01

    The objective of this study was to explore sex differences in development from infancy to 8 years of age in a community sample. Measures of biological, social, interactive, and parental functioning as well as teacher reports were obtained. There were minimal differences in infancy, but major psychosocial differences emerged with increasing age. In the biological sphere boys were disadvantaged only in ratings of language and motor skills at 3 to 4 years old. They showed greater temperamental "difficulty" and low persistence factor scores from 5 years onward. Boys were significantly more likely to have problems with adaptive behavior and social competence and to show behavior problems of the hyperactive and aggressive type, as rated by mothers. Parent and family functioning measures did not differentiate between the sexes. Teachers rated boys as having more problems in academic and behavioral domains the first 3 years of school. Path analyses combining data sets gathered when the children were 3 to 8 years old demonstrated the differential courses of development for boys and girls although temperamental flexibility was the best predictor of behavioral adjustment for both sexes. A social learning explanation of the increased incidence of problems among males is supported, although biological influences are not ruled out.

  16. Synchronization dynamics of two different dynamical systems

    International Nuclear Information System (INIS)

    Luo, Albert C.J.; Min Fuhong

    2011-01-01

    Highlights: → Synchronization dynamics of two distinct dynamical systems. → Synchronization, de-synchronization and instantaneous synchronization. → A controlled pendulum synchronizing with the Duffing oscillator. → Synchronization invariant set. → Synchronization parameter map. - Abstract: In this paper, synchronization dynamics of two different dynamical systems is investigated through the theory of discontinuous dynamical systems. The necessary and sufficient conditions for the synchronization, de-synchronization and instantaneous synchronization (penetration or grazing) are presented. Using such a synchronization theory, the synchronization of a controlled pendulum with the Duffing oscillator is systematically discussed as a sampled problem, and the corresponding analytical conditions for the synchronization are presented. The synchronization parameter study is carried out for a better understanding of synchronization characteristics of the controlled pendulum and the Duffing oscillator. Finally, the partial and full synchronizations of the controlled pendulum with periodic and chaotic motions are presented to illustrate the analytical conditions. The synchronization of the Duffing oscillator and pendulum are investigated in order to show the usefulness and efficiency of the methodology in this paper. The synchronization invariant domain is obtained. The technique presented in this paper should have a wide spectrum of applications in engineering. For example, this technique can be applied to the maneuvering target tracking, and the others.

  17. Attachment is a dynamic system

    Directory of Open Access Journals (Sweden)

    Zlatka Cugmas

    2003-04-01

    Full Text Available On the basis of the study of recent scientific literature about the development of attachment, the author answers the following questions: which are the postulates the theory of attachment has about the stability of the patterns of attachment, which level of stability in the patterns of attachment from infancy to adulthood these studies illuminate and which factors significantly influence the (instability of the patterns of attachment in time. The theory of attachment assumes that normal circumstances elicit stability. Changes, however, can be the result of important events influencing the sensitivity of the object of attachment. Agreement has not yet been reached regarding the percentage of stability in the patterns of attachment. There is more agreement regarding attachment in adulthood than that in childhood. The results depend on the size and characteristics of the subjects of the research, the measuring instruments, type of data analysis etc. The author concludes that attachment is a dynamic system influenced by significant changes in life (the cognitive development of the child, external care, parents' divorce, different stressful situations. As the influence of stressful events on the individual person' s quality of attachment is examined, it is necessary to consider also his/her temperamental characteristics, role of other people in their lives, etc.

  18. Latent Class Symptom Profiles of Selective Mutism: Identification and Linkage to Temperamental and Social Constructs.

    Science.gov (United States)

    Diliberto, Rachele; Kearney, Christopher A

    2017-11-21

    Selective mutism (SM) is a stable, debilitating psychiatric disorder in which a child fails to speak in most public situations. Considerable debate exists as to the typology of this population, with empirically-based studies pointing to possible dimensions of anxiety, oppositionality, and communication problems, among other aspects. Little work has juxtaposed identified symptom profiles with key temperamental and social constructs often implicated in SM. The present study examined a large, diverse, non-clinical, international sample of children aged 6-10 years with SM to empirically identify symptom profiles and to link these profiles to key aspects of temperament (i.e., emotionality, shyness, sociability, activity) and social functioning (i.e., social problems, social competence). Exploratory and confirmatory factor analysis revealed anxiety/distress, oppositionality, and inattention domains. In addition, latent class analysis revealed nuanced profiles labeled as (1) moderately anxious, oppositional, and inattentive, (2) highly anxious, and moderately oppositional and inattentive, and (3) mildly to moderately anxious, and mildly oppositional and inattentive. Class 2 was the most impaired group and was associated with greater emotionality, shyness, and social problems. Class 3 was the least impaired group and was associated with better sociability and social competence and activity. Class 1 was largely between the other classes, demonstrating less shyness and social problems than Class 2. The results help confirm previous findings of anxiety and oppositional profiles among children with SM but that nuanced classes may indicate subtle variations in impairment. The results have implications not only for subtyping this population but also for refining assessment and case conceptualization strategies and pursuing personalized and perhaps less lengthy treatment.

  19. Dynamic photosynthesis in different environmental conditions.

    Science.gov (United States)

    Kaiser, Elias; Morales, Alejandro; Harbinson, Jeremy; Kromdijk, Johannes; Heuvelink, Ep; Marcelis, Leo F M

    2015-05-01

    Incident irradiance on plant leaves often fluctuates, causing dynamic photosynthesis. Whereas steady-state photosynthetic responses to environmental factors have been extensively studied, knowledge of dynamic modulation of photosynthesis remains scarce and scattered. This review addresses this discrepancy by summarizing available data and identifying the research questions necessary to advance our understanding of interactions between environmental factors and dynamic behaviour of photosynthesis using a mechanistic framework. Firstly, dynamic photosynthesis is separated into sub-processes related to proton and electron transport, non-photochemical quenching, control of metabolite flux through the Calvin cycle (activation states of Rubisco and RuBP regeneration, and post-illumination metabolite turnover), and control of CO₂ supply to Rubisco (stomatal and mesophyll conductance changes). Secondly, the modulation of dynamic photosynthesis and its sub-processes by environmental factors is described. Increases in ambient CO₂ concentration and temperature (up to ~35°C) enhance rates of photosynthetic induction and decrease its loss, facilitating more efficient dynamic photosynthesis. Depending on the sensitivity of stomatal conductance, dynamic photosynthesis may additionally be modulated by air humidity. Major knowledge gaps exist regarding environmental modulation of loss of photosynthetic induction, dynamic changes in mesophyll conductance, and the extent of limitations imposed by stomatal conductance for different species and environmental conditions. The study of mutants or genetic transformants for specific processes under various environmental conditions could provide significant progress in understanding the control of dynamic photosynthesis. © The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  20. Modulation of neuronal dynamic range using two different adaptation mechanisms

    Directory of Open Access Journals (Sweden)

    Lei Wang

    2017-01-01

    Full Text Available The capability of neurons to discriminate between intensity of external stimulus is measured by its dynamic range. A larger dynamic range indicates a greater probability of neuronal survival. In this study, the potential roles of adaptation mechanisms (ion currents in modulating neuronal dynamic range were numerically investigated. Based on the adaptive exponential integrate-and-fire model, which includes two different adaptation mechanisms, i.e. subthreshold and suprathreshold (spike-triggered adaptation, our results reveal that the two adaptation mechanisms exhibit rather different roles in regulating neuronal dynamic range. Specifically, subthreshold adaptation acts as a negative factor that observably decreases the neuronal dynamic range, while suprathreshold adaptation has little influence on the neuronal dynamic range. Moreover, when stochastic noise was introduced into the adaptation mechanisms, the dynamic range was apparently enhanced, regardless of what state the neuron was in, e.g. adaptive or non-adaptive. Our model results suggested that the neuronal dynamic range can be differentially modulated by different adaptation mechanisms. Additionally, noise was a non-ignorable factor, which could effectively modulate the neuronal dynamic range.

  1. TEMPERAMENTAL ADAPTABILITY, PERSISTENCE, AND REGULARITY: PARENTAL RATINGS OF NORWEGIAN INFANTS AGED 6 TO 12 MONTHS, WITH SOME IMPLICATIONS FOR PREVENTIVE PRACTICE.

    Science.gov (United States)

    Olafsen, Kåre S; Ulvund, Stein Erik; Torgersen, Anne Mari; Wentzel-Larsen, Tore; Smith, Lars; Moe, Vibeke

    2018-03-01

    There is a need for standardized measures of infant temperament to strengthen current practices in prevention and early intervention. The present study provides Norwegian data on the Cameron-Rice Infant Temperament Questionnaire (CRITQ; J.R. Cameron & D.C. Rice, 1986a), which comprises 46 items and is used within a U.S. health maintenance organization. The CRITQ was filled out by mothers and fathers at 6 and again at 12 months as part of a longitudinal study of mental health during the first years of life (the "Little in Norway" study, N = 1,041 families enrolled; V. Moe & L. Smith, 2010). Results showed that internal consistencies were comparable with U.S. The temperament dimensions of persistence, adaptability, and regularity had acceptable or close-to-acceptable reliabilities in the U.S. study as well as in this study, and also were unifactorial in confirmatory factor analysis. These dimensions are the focus in this article. Findings concerning parents' differential ratings of their infants on the three dimensions are reported, as is the stability of parents' ratings of temperament from 6 to 12 months. In addition, results on the relation between temperament and parenting stress are presented. The study suggests that temperamental adaptability, persistence, and regularity may be relevant when assessing infant behavior, and may be applied in systematic prevention trials for families with infants. The inclusion of concepts related to individual differences in response tendencies and regulatory efforts may broaden the understanding of parent-infant transactions, and thus enrich prevention and sensitizing interventions with the aim of assisting infants' development. © 2018 Michigan Association for Infant Mental Health.

  2. Shy Children Are Less Sensitive to Some Cues to Facial Recognition

    Science.gov (United States)

    Brunet, Paul M.; Mondloch, Catherine J.; Schmidt, Louis A.

    2010-01-01

    Temperamental shyness in children is characterized by avoidance of faces and eye contact, beginning in infancy. We conducted two studies to determine whether temperamental shyness was associated with deficits in sensitivity to some cues to facial identity. In Study 1, 40 typically developing 10-year-old children made same/different judgments about…

  3. Temperamental Differences in Children’s Reactions to Peer Victimization

    Science.gov (United States)

    Sugimura, Niwako; Rudolph, Karen D.

    2015-01-01

    Objective This research examined the hypothesis that temperament and sex moderate the contribution of peer victimization to children’s subsequent adjustment (aggression and depressive symptoms). Method Children (125 boys, 158 girls; M age = 7.95 years, SD = 0.32; 77.7% White, 22.3% minority) and teachers reported on overt and relational victimization. Parents rated children’s temperament (inhibitory control and negative emotionality) and depressive symptoms, and teachers reported on children’s overt and relational aggression. Results Across a one-year time period, (a) overt victimization predicted overt aggression in girls with poor inhibitory control; (b) overt and relational victimization predicted depressive symptoms in girls with high negative emotionality; and (c) relational victimization predicted depressive symptoms in boys with low negative emotionality. Conclusions This research helps to explain individual variation in children’s reactions to peer victimization, and has implications for person-by-environment models of development. Moreover, this research informs the development of targeted intervention programs for victimized youth that bolster specific resources depending on their temperament. PMID:22420650

  4. Biomechanical assessment of dynamic balance: Specificity of different balance tests.

    Science.gov (United States)

    Ringhof, Steffen; Stein, Thorsten

    2018-04-01

    Dynamic balance is vitally important for most sports and activities of daily living, so the assessment of dynamic stability has become an important issue. In consequence, a large number of balance tests have been developed. However, it is not yet known whether these tests (i) measure the same construct and (ii) can differentiate between athletes with different balance expertise. We therefore studied three common dynamic balance tests: one-leg jump landings, Posturomed perturbations and simulated forward falls. Participants were 24 healthy young females in regular training in either gymnastics (n = 12) or swimming (n = 12). In each of the tests, the participants were instructed to recover balance as quickly as possible. Dynamic stability was computed by time to stabilization and margin of stability, deduced from force plates and motion capture respectively. Pearson's correlations between the dynamic balance tests found no significant associations between the respective dynamic stability measures. Furthermore, independent t-tests indicated that only jump landings could properly distinguish between both groups of athletes. In essence, the different dynamic balance tests applied did not measure the same construct but rather task-specific skills, each of which depends on multifactorial internal and external constraints. Our study therefore contradicts the traditional view of considering balance as a general ability, and reinforces that dynamic balance measures are not interchangeable. This highlights the importance of selecting appropriate balance tests. Copyright © 2018 Elsevier B.V. All rights reserved.

  5. Does temperamental instability support a continuity between bipolar II disorder and major depressive disorder?

    Science.gov (United States)

    Benazzi, F

    2006-06-01

    The current categorical split of mood disorders in bipolar disorders and depressive disorders has recently been questioned. Two highly unstable personality features, i.e. the cyclothymic temperament (CT) and borderline personality disorder (BPD), have been found to be more common in bipolar II (BP-II) disorder than in major depressive disorder (MDD). According to Kraepelin, temperamental instability was the "foundation" of his unitary view of mood disorders. The aim was to assess the distributions of the number of CT and borderline personality items between BP-II and MDD. Finding no bi-modal distribution (a "zone of rarity") of these items would support a continuity between the two disorders. an outpatient psychiatry private practice. Interviewer: A senior clinical and mood disorder research psychiatrist. A consecutive sample of 138 BP-II and 71 MDD remitted outpatients. Assessment instruments: The structured clinical interview for DSM-IV Axis I Disorders-Clinician Version (SCID-CV), the SCID-II Personality Questionnaire for self-assessing borderline personality traits (BPT) by patients, the TEMPS-A for self-assessing CT by patients. Interview methods: Patients were interviewed with the SCID-CV to diagnose BP-II and MDD, and then patients self-assessed the questions of the Personality Questionnaire relative to borderline personality, and the questions of the TEMPS-A relative to CT. As clinically significant distress or impairment of functioning is not assessed by the SCID-II Personality Questionnaire, a diagnosis of BPD could not be made, but BPT could be assessed (i.e. all BPD items but not the impairment criterion). The distribution of the number of CT and BPT items was studied by Kernel density estimate. CT and BPT items were significantly more common in BP-II versus MDD. The Kernel density estimate distributions of the number of CT and BPT items in the entire sample had a normal-like shape (i.e. no bi-modality). The expected finding, on the basis of previous

  6. Dynamics of quantum-classical differences for chaotic systems

    International Nuclear Information System (INIS)

    Ballentine, L.E.

    2002-01-01

    The differences between quantum and classical dynamics can be studied through the moments and correlations of the position and momentum variables in corresponding quantum and classical statistical states. In chaotic states the quantum-classical differences grow exponentially with an exponent that exceeds the classical Lyapunov exponent. It is shown analytically that the quantum-classical differences scale as (ℎ/2π) 2 , and that the exponent for the growth of these differences is independent of (ℎ/2π). The quantum-classical difference exponent is studied for two quartic potential models, and the results are compared with previous work on the Henon-Heiles model

  7. VERIFICATION OF GEAR DYNAMIC MODEL IN DIFFERENT OPERATING CONDITIONS

    Directory of Open Access Journals (Sweden)

    Grzegorz PERUŃ

    2014-09-01

    Full Text Available The article presents the results of verification of the drive system dynamic model with gear. Tests were carried out on the real object in different operating conditions. For the same assumed conditions were also carried out simulation studies. Comparison of the results obtained from those two series of tests helped determine the suitability of the model and verify the possibility of replacing experimental research by simulations with use of dynamic model.

  8. Exploring difference as a dynamic of dialogue

    DEFF Research Database (Denmark)

    Phillips, Louise Jane

    are recognized as legitimate. Crucially, difference is viewed as the transformative force in the co-construction of knowledge in dialogue. By harnessing difference as a transformative force, it is claimed, dialogue can generate knowledge across difference, including differences of organizational position...... and professional background, theoretical perspective, gender, ethnicity, class and so on. But how exactly is knowledge co-produced in dialogue through the harnessing of “difference” as a transformative force? And what tensions are in play in dynamics of inclusion and exclusion where some voices, articulating......-centred” care for residents with dementia. The theoretical framework, The Integrated Framework for Analysing Dialogic Knowledge Production and Communication (IFADIA), is based on a combination of Bakhtinian dialogic communication theory and Foucault’s theorization of discourse and power...

  9. On the number of different dynamics in Boolean networks with deterministic update schedules.

    Science.gov (United States)

    Aracena, J; Demongeot, J; Fanchon, E; Montalva, M

    2013-04-01

    Deterministic Boolean networks are a type of discrete dynamical systems widely used in the modeling of genetic networks. The dynamics of such systems is characterized by the local activation functions and the update schedule, i.e., the order in which the nodes are updated. In this paper, we address the problem of knowing the different dynamics of a Boolean network when the update schedule is changed. We begin by proving that the problem of the existence of a pair of update schedules with different dynamics is NP-complete. However, we show that certain structural properties of the interaction diagraph are sufficient for guaranteeing distinct dynamics of a network. In [1] the authors define equivalence classes which have the property that all the update schedules of a given class yield the same dynamics. In order to determine the dynamics associated to a network, we develop an algorithm to efficiently enumerate the above equivalence classes by selecting a representative update schedule for each class with a minimum number of blocks. Finally, we run this algorithm on the well known Arabidopsis thaliana network to determine the full spectrum of its different dynamics. Copyright © 2013 Elsevier Inc. All rights reserved.

  10. Dynamic postural stability differences between male and female players with and without ankle sprain

    NARCIS (Netherlands)

    Dallinga, Joan; van der Does, Henrike; Benjaminse, Anne; Lemmink, Koen

    2015-01-01

    Objectives: The strategy for dynamic postural stability might be different for male and female players. Additionally, dynamic and challenging tasks are recommended to measure differences in postural stability between injured and non-injured players. Therefore, the dynamic stability index (DSI) was

  11. Differences in dynamic and static functional connectivity between young and elderly healthy adults

    Energy Technology Data Exchange (ETDEWEB)

    Park, Ji Eun; Jung, Seung Chai; Ryu, Kyeoung Hwa; Oh, Joo Young; Kim, Ho Sung; Choi, Choong-Gon; Kim, Sang Joon; Shim, Woo Hyun [University of Ulsan College of Medicine, Asan Medical Center, Department of Radiology and Research Institute of Radiology, Songpa-Gu, Seoul (Korea, Republic of)

    2017-08-15

    Brain connectivity is highly dynamic, but functional connectivity (FC) studies using resting-state functional magnetic resonance imaging (rs-fMRI) assume it to be static. This study assessed differences in dynamic FC between young healthy adults (YH) and elderly healthy adults (EH) compared to static FC. Using rs-fMRI data from 12 YH and 31 EH, FC was assessed in six functional regions (subcortical, auditory [AUD], sensorimotor [SM], visuospatial [VS], cognitive control [CC], and default mode network [DMN]). Static FC was calculated as Fisher's z-transformed correlation coefficient. The sliding time window correlation (window size 30 s, step size 3 s) was applied for dynamic FC, and the standard deviation across sliding windows was calculated. Differences in static and dynamic FC between EH and YH were calculated and compared by region. EH showed decreased static FC in the subcortical, CC, and DMN regions (FDR corrected p = 0.0013; 74 regions), with no regions showing static FC higher than that in YH. EH showed increased dynamic FC in the subcortical, CC, and DMN regions, whereas decreased dynamic FC in CC and DMN regions (p < 0.01). However, the regions showing differences between EH and YH did not overlap between static and dynamic FC. Dynamic FC exhibited differences from static FC in EH and YH, mainly in regions involved in cognitive control and the DMN. Altered dynamic FC demonstrated both qualitatively and quantitatively distinct patterns of transient brain activity and needs to be studied as an imaging biomarker in the aging process. (orig.)

  12. Local difference measures between complex networks for dynamical system model evaluation.

    Science.gov (United States)

    Lange, Stefan; Donges, Jonathan F; Volkholz, Jan; Kurths, Jürgen

    2015-01-01

    A faithful modeling of real-world dynamical systems necessitates model evaluation. A recent promising methodological approach to this problem has been based on complex networks, which in turn have proven useful for the characterization of dynamical systems. In this context, we introduce three local network difference measures and demonstrate their capabilities in the field of climate modeling, where these measures facilitate a spatially explicit model evaluation.Building on a recent study by Feldhoff et al. [8] we comparatively analyze statistical and dynamical regional climate simulations of the South American monsoon system [corrected]. types of climate networks representing different aspects of rainfall dynamics are constructed from the modeled precipitation space-time series. Specifically, we define simple graphs based on positive as well as negative rank correlations between rainfall anomaly time series at different locations, and such based on spatial synchronizations of extreme rain events. An evaluation against respective networks built from daily satellite data provided by the Tropical Rainfall Measuring Mission 3B42 V7 reveals far greater differences in model performance between network types for a fixed but arbitrary climate model than between climate models for a fixed but arbitrary network type. We identify two sources of uncertainty in this respect. Firstly, climate variability limits fidelity, particularly in the case of the extreme event network; and secondly, larger geographical link lengths render link misplacements more likely, most notably in the case of the anticorrelation network; both contributions are quantified using suitable ensembles of surrogate networks. Our model evaluation approach is applicable to any multidimensional dynamical system and especially our simple graph difference measures are highly versatile as the graphs to be compared may be constructed in whatever way required. Generalizations to directed as well as edge- and node

  13. The population dynamical implications of male-biased parasitism in different mating systems.

    Directory of Open Access Journals (Sweden)

    Martin R Miller

    2007-07-01

    Full Text Available Although there is growing evidence that males tend to suffer higher levels of parasitism than females, the implications of this for the population dynamics of the host population are not yet understood. Here we build on an established 'two-sex' model and investigate how increased susceptibility to infection in males affects the dynamics, under different mating systems. We investigate the effect of pathogenic disease at different case mortalities, under both monogamous and polygynous mating systems. If the case mortality is low, then male-biased parasitism appears similar to unbiased parasitism in terms of its effect on the population dynamics. At higher case mortalities, we identified significant differences between male-biased and unbiased parasitism. A host population may therefore be differentially affected by male-biased and unbiased parasitism. The dynamical outcome is likely to depend on a complex interaction between the host's mating system and demography, and the parasite virulence.

  14. Dynamic Performance Analysis for an Absorption Chiller under Different Working Conditions

    Directory of Open Access Journals (Sweden)

    Jian Wang

    2017-08-01

    Full Text Available Due to the merits of energy saving and environmental protection, the absorption chiller (AC has attracted a lot of attention, and previous studies only concentrated on the dynamic response of the AC under a single working condition. However, the working conditions are usually variable, and the dynamic performance under different working conditions is beneficial for the adjustment of AC and the control of the whole system, of which the stabilization can be affected by the AC transient process. Therefore, the steady and dynamic models of a single-effect H2O-LiBr absorption chiller are built up, the thermal inertia and fluid storage are also taken into consideration. And the dynamic performance analyses of the AC are completed under different external parameters. Furthermore, a whole system using AC in a process plant is analyzed. As a conclusion, the time required to reach a new steady-state (relaxation time increases when the step change of the generator inlet temperature becomes large, the cooling water inlet temperature rises, or the evaporator inlet temperature decreases. In addition, the control strategy considering the AC dynamic performance is favorable to the operation of the whole system.

  15. The dynamic efficiency of feed-in tariffs: The impact of different design elements

    International Nuclear Information System (INIS)

    Río, Pablo del

    2012-01-01

    Dynamic efficiency has received much less attention than the effectiveness and static efficiency criteria to assess policies to support electricity from renewable energy sources (RES-E). On the other hand, the literature on RES-E support shows that the choice of design elements within RES-E support instruments is at least as important to successfully promote RES-E as the choice of specific instruments. The aim of this paper is to build a theoretical framework for dynamic efficiency analysis and assess the dynamic efficiency properties of the different design elements of feed-in tariffs. It is shown that, in fact, several design elements can have a significant impact on the different dimensions of dynamic efficiency. Particularly relevant design elements in this context are technology-specific fixed-tariffs, floor prices, degression, reductions of support over time for existing plants, long duration of support and support falling on consumers. In addition, it is shown than some design elements would be more appropriate than others to activate specific dimensions. - Highlights: ► A theoretical framework for dynamic efficiency analysis is built. ► The dynamic efficiency properties of feed-in tariffs design elements are assessed. ► Several design elements have a significant impact on the different dimensions of dynamic efficiency.

  16. Lifespan Differences in Nonlinear Dynamics during Rest and Auditory Oddball Performance

    Science.gov (United States)

    Muller, Viktor; Lindenberger, Ulman

    2012-01-01

    Electroencephalographic recordings (EEG) were used to assess age-associated differences in nonlinear brain dynamics during both rest and auditory oddball performance in children aged 9.0-12.8 years, younger adults, and older adults. We computed nonlinear coupling dynamics and dimensional complexity, and also determined spectral alpha power as an…

  17. Active synchronization between two different chaotic dynamical system

    International Nuclear Information System (INIS)

    Maheri, M.; Arifin, N. Md; Ismail, F.

    2015-01-01

    In this paper we investigate on the synchronization problem between two different chaotic dynamical system based on the Lyapunov stability theorem by using nonlinear control functions. Active control schemes are used for synchronization Liu system as drive and Rossler system as response. Numerical simulation by using Maple software are used to show effectiveness of the proposed schemes

  18. Active synchronization between two different chaotic dynamical system

    Energy Technology Data Exchange (ETDEWEB)

    Maheri, M. [Institute for Mathematical Research, 43400 UPM, Serdang, Selengor (Malaysia); Arifin, N. Md; Ismail, F. [Department of Mathematics, 43400 UPM, Serdang, Selengor (Malaysia)

    2015-05-15

    In this paper we investigate on the synchronization problem between two different chaotic dynamical system based on the Lyapunov stability theorem by using nonlinear control functions. Active control schemes are used for synchronization Liu system as drive and Rossler system as response. Numerical simulation by using Maple software are used to show effectiveness of the proposed schemes.

  19. [Dynamic vision of sportsmen with different requirement profiles for the visual apparatus].

    Science.gov (United States)

    Lüder, A; Andexer, V; Witte, K; Böckelmann, I

    2011-12-01

    In particular, in the quick ball and racket games a good dynamic seeing is required . The afferent dynamic seeing occurs via the retiina which mediates the stimuli for efferent dynamic seeing . The aim of this study was to examine the dynamic visual acuity of sportsmen from sports with different demands on their dynamic seeing (DS). 19 sports students took part in the study. 10 subjects participated in coached team sports (group I) and 9 remaining performed individual sports (group II). The DS was assessed by means of the Düsseldorfer test for dynamic seeing of Wist which was performed twice on one day. The DS of the two groups in the first study did not differ (right eye 95.7 ± 10.6 % in group I vs. 94.3 ± 6.9 % in group II and left eye 97.6 ± 4.8 % vs. 95.3 ± 5.6 %; p ≥ 0.05). Also the second study there was no different in DS for the two groups (right eye 98.3 ± 2.6 % vs. 93.8 ± 8.0 % and left eye 99.3 ± 1.2 % vs. 95.6 ± 7.0 %; p ≥ 0.05). Our hypothesis about a different DS in players of ball games compared with non-ball sport players could not be proved. It is to be critically noted that a generalization is not possible due to the small sample numbers. Because DS is a necessary precondition in ball games further studies should be concentrated on its trainability. © Georg Thieme Verlag KG Stuttgart · New York.

  20. Using Difference Equation to Model Discrete-time Behavior in System Dynamics Modeling

    NARCIS (Netherlands)

    Hesan, R.; Ghorbani, A.; Dignum, M.V.

    2014-01-01

    In system dynamics modeling, differential equations have been used as the basic mathematical operator. Using difference equation to build system dynamics models instead of differential equation, can be insightful for studying small organizations or systems with micro behavior. In this paper we

  1. Different dynamic behaviors of the dissociation and recombination reactions in a model calculation of polyethylene by first-principles steered molecular dynamics simulation

    International Nuclear Information System (INIS)

    Higuchi, Yuji; Ishikawa, Takeshi; Ozawa, Nobuki; Chazeau, Laurent; Cavaillé, Jean-Yves; Kubo, Momoji

    2015-01-01

    Highlights: • We study the different dynamics of dissociation and recombination processes. • Hydrogen at the chain ends collides each other in the recombination process. • Dissociation and recombination processes take different pathway. - Abstract: We investigate the different dynamics of the stress-induced dissociation and recombination reactions in a model of polyethylene by a first-principles molecular dynamics simulation at the B3LYP/6-31g(d) level. The dissociation under external forces acting on the chemical reaction site at 300 K follows the same pathway as the one calculated by the static first-principles method because it has a similar activation barrier to that of the static first-principles calculation. On the other hand, in the recombination process, thermal fluctuations causes collisions between hydrogen atoms at the chain ends. Furthermore, when external forces do not directly act on the chemical reaction site, two different dissociation processes are observed. On the other hand, recombination process is not observed due to rarely contact of the radical carbon. These results indicate that dissociation and recombination dynamics are very different, showing the importance of the dynamic calculation.

  2. Acute effects of different dynamic exercises on hamstring strain risk factors.

    Science.gov (United States)

    Chen, Che Hsiu; Xin, Ye; Lee, Kuang Wu; Lin, Ming Ju; Lin, Jiu Jenq

    2018-01-01

    The purpose of the study was to examine the acute effects of different dynamic exercise interventions on hamstring muscle performance. Thirty-six young men with poor hamstring flexibility were randomly assigned to three intervention groups: jogging combined with dynamic open kinetic chain stretching (DS), jogging combined with dynamic closed kinetic chain stretching (lunge with eccentric hamstring windmills, LEC), and jogging only (CON) groups. Hamstring flexibility, muscle stiffness (area under the curve, AUC), joint position sense (JPS), maximal eccentric strength (ECC), and angle of peak torque (APT) were recorded before and immediately after the exercise interventions. The results showed that the hamstring flexibility increased in DS (p < 0.001); muscle stiffness decreased in DS and was lower than jogging (p < 0.001). Moreover, ECC increased in LEC and was higher than jogging and DS (p < 0.001). APT was different among 3 groups (p < 0.001). Decreased accuracy of JPS was found in DS and jogging (p < 0.001). In conclusion, the dynamic closed kinetic chain stretching (LEC) as compared to open kinetic chain stretching (DS) or jogging group, may be an effective technique to enhance muscle performance during the pre-competition warm-up routine.

  3. Distributed Dynamic Traffic Modeling and Implementation Oriented Different Levels of Induced Travelers

    Directory of Open Access Journals (Sweden)

    Yan Liu

    2015-01-01

    Full Text Available In order to respond to the variable state of traffic network in time, a distributed dynamic traffic assignment strategy is proposed which can improve the intelligent traffic management. The proposed dynamic assignment method is based on utility theory and is oriented to different levels of induced users. A distributed model based on the marginal utility is developed which combines the advantages of both decentralized paradigm and traveler preference, so as to provide efficient and robust dynamic traffic assignment solutions under uncertain network conditions. Then, the solution algorithm including subroute update and subroute calculation is proposed. To testify the effectiveness of the proposed model in optimizing traffic network operation and minimizing traveler’s cost on different induced levels, a sequence numerical experiment is conducted. In the experiment, there are two test environments: one is in different network load conditions and the other is in different deployment coverage of local agents. The numerical results show that the proposed model not only can improve the running efficiency of road network but also can significantly decrease the average travel time.

  4. Solvation Dynamics in Different Phases of the Lyotropic Liquid Crystalline System.

    Science.gov (United States)

    Roy, Bibhisan; Satpathi, Sagar; Gavvala, Krishna; Koninti, Raj Kumar; Hazra, Partha

    2015-09-03

    Reverse hexagonal (HII) liquid crystalline material based on glycerol monooleate (GMO) is considered as a potential carrier for drugs and other important biomolecules due to its thermotropic phase change and excellent morphology. In this work, the dynamics of encapsulated water, which plays important role in stabilization and formation of reverse hexagonal mesophase, has been investigated by time dependent Stokes shift method using Coumarin-343 as a solvation probe. The formation of the reverse hexagonal mesophase (HII) and transformation to the L2 phase have been monitored using small-angle X-ray scattering and polarized light microscopy experiments. REES studies suggest the existence of different polar regions in both HII and L2 systems. The solvation dynamics study inside the reverse hexagonal (HII) phase reveals the existence of two different types of water molecules exhibiting dynamics on a 120-900 ps time scale. The estimated diffusion coefficients of both types of water molecules obtained from the observed dynamics are in good agreement with the measured diffusion coefficient collected from the NMR study. The calculated activation energy is found to be 2.05 kcal/mol, which is associated with coupled rotational-translational water relaxation dynamics upon the transition from "bound" to "quasi-free" state. The observed ∼2 ns faster dynamics of the L2 phase compared to the HII phase may be associated with both the phase transformation as well as thermotropic effect on the relaxation process. Microviscosities calculated from time-resolved anisotropy studies infer that the interface is almost ∼22 times higher viscous than the central part of the cylinder. Overall, our results reveal the unique dynamical features of water inside the cylinder of reverse hexagonal and inverse micellar phases.

  5. Entanglement dynamics of two-qubit systems in different quantum noises

    International Nuclear Information System (INIS)

    Pan Chang-Ning; Fang Jian-Shu; Li-Fei; Fang Mao-Fa

    2011-01-01

    The entanglement dynamics of two-qubit systems in different quantum noises are investigated by means of the operator-sum representation method. We find that, except for the amplitude damping and phase damping quantum noise, the sudden death of entanglement is always observed in different two-qubit systems with generalized amplitude damping and depolarizing quantum noise. (general)

  6. Model-based analysis of postprandial glycemic response dynamics for different types of food

    Directory of Open Access Journals (Sweden)

    Yvonne J. Rozendaal

    2018-06-01

    Full Text Available Summary: Background & aims: Knowledge of postprandial glycemic response (PPGR dynamics is important in nutrition management and diabetes research, care and (selfmanagement. In daily life, food intake is the most important factor influencing the occurrence of hyperglycemia. However, the large variability in PPGR dynamics to different types of food is inadequately predicted by existing glycemic measures. The objective of this study was therefore to quantitatively describe PPGR dynamics using a systems approach. Methods: Postprandial glucose and insulin data were collected from literature for many different food products and mixed meals. The predictive value of existing measures, such as the Glycemic Index, was evaluated. A physiology-based dynamic model was used to reconstruct the full postprandial response profiles of both glucose and insulin simultaneously. Results: We collected a large range of postprandial glucose and insulin dynamics for 53 common food products and mixed meals. Currently available glycemic measures were found to be inadequate to describe the heterogeneity in postprandial dynamics. By estimating model parameters from glucose and insulin data, the physiology-based dynamic model accurately describes the measured data whilst adhering to physiological constraints. Conclusions: The physiology-based dynamic model provides a systematic framework to analyze postprandial glucose and insulin profiles. By changing parameter values the model can be adjusted to simulate impaired glucose tolerance and insulin resistance. Keywords: Postprandial glycemic response, Physiology-based dynamic model, Food intake, Computational modeling, Glucose, Insulin

  7. Vortex Dynamics in Superconductors with Different Types of Pinning Potentials

    International Nuclear Information System (INIS)

    Laguna, Maria Fabiana

    2001-01-01

    In this work we study the behavior of the vortex system in the mixed state of a type II superconductor when it interacts with different kinds of pinning potentials. To do this, we perform numerical simulations in the presence of an external magnetic field, by making use of two different approaches.One corresponds to a Langevin simulation of the three dimensional XY model or Josephson-junction network, whereas the other corresponds to a Molecular dynamics simulation of two dimensional point-like vortices.We analyze the transport properties of highly anisotropic superconductors with different kinds of topological disorder in the configuration in which the external field is applied perpendicular to the CuO planes.We found that for systems with point defects the activation energy is the same for the two components of the resistivity, while in systems with columnar defects the activation energies can be different.We also study the structure, phase transitions and transport properties of the vortex system when the external magnetic field lies parallel to the planes in layered superconductors. We analyze the stability of different phases at low temperatures and show under which conditions the smectic phase is stable.Our results indicate the presence of the smectic phase in an intermediate range of temperatures.We have studied a vortex array in a periodic pinning potential with triangular and kagome geometries.We obtain the ground state vortex configurations and calculate some thermodynamic quantities for different magnetic fields.We observe several stages of lattice pinning and melting and we characterize different phases and transitions between them.Finally, simulating the Bitter pinning effect over the vortex system, we study static and dynamic properties of the vortex system in the presence of the surface Bitter pinning and the bulk pinning.We found low temperature structures similar to those obtained experimentally.We analyze the dynamics of the nucleation and growth

  8. Individual Differences in Dynamic Functional Brain Connectivity across the Human Lifespan.

    Directory of Open Access Journals (Sweden)

    Elizabeth N Davison

    2016-11-01

    Full Text Available Individual differences in brain functional networks may be related to complex personal identifiers, including health, age, and ability. Dynamic network theory has been used to identify properties of dynamic brain function from fMRI data, but the majority of analyses and findings remain at the level of the group. Here, we apply hypergraph analysis, a method from dynamic network theory, to quantify individual differences in brain functional dynamics. Using a summary metric derived from the hypergraph formalism-hypergraph cardinality-we investigate individual variations in two separate, complementary data sets. The first data set ("multi-task" consists of 77 individuals engaging in four consecutive cognitive tasks. We observe that hypergraph cardinality exhibits variation across individuals while remaining consistent within individuals between tasks; moreover, the analysis of one of the memory tasks revealed a marginally significant correspondence between hypergraph cardinality and age. This finding motivated a similar analysis of the second data set ("age-memory", in which 95 individuals, aged 18-75, performed a memory task with a similar structure to the multi-task memory task. With the increased age range in the age-memory data set, the correlation between hypergraph cardinality and age correspondence becomes significant. We discuss these results in the context of the well-known finding linking age with network structure, and suggest that hypergraph analysis should serve as a useful tool in furthering our understanding of the dynamic network structure of the brain.

  9. Applying a System Dynamics Approach for Modeling Groundwater Dynamics to Depletion under Different Economical and Climate Change Scenarios

    Directory of Open Access Journals (Sweden)

    Hamid Balali

    2015-09-01

    Full Text Available In the recent decades, due to many different factors, including climate change effects towards be warming and lower precipitation, as well as some structural policies such as more intensive harvesting of groundwater and low price of irrigation water, the level of groundwater has decreased in most plains of Iran. The objective of this study is to model groundwater dynamics to depletion under different economic policies and climate change by using a system dynamics approach. For this purpose a dynamic hydro-economic model which simultaneously simulates the farmer’s economic behavior, groundwater aquifer dynamics, studied area climatology factors and government economical policies related to groundwater, is developed using STELLA 10.0.6. The vulnerability of groundwater balance is forecasted under three scenarios of climate including the Dry, Nor and Wet and also, different scenarios of irrigation water and energy pricing policies. Results show that implementation of some economic policies on irrigation water and energy pricing can significantly affect on groundwater exploitation and its volume balance. By increasing of irrigation water price along with energy price, exploitation of groundwater will improve, in so far as in scenarios S15 and S16, studied area’s aquifer groundwater balance is positive at the end of planning horizon, even in Dry condition of precipitation. Also, results indicate that climate change can affect groundwater recharge. It can generally be expected that increases in precipitation would produce greater aquifer recharge rates.

  10. The Big Five personality and temperamental traits and its correlation with styles of coping with stress in the fire brigade officers

    Directory of Open Access Journals (Sweden)

    Justyna Szrajda

    2017-09-01

    Full Text Available Selecting specific professional activities (e.g. a brigade officer and methods for coping with difficult situations may result from personal predispositions of a given person. Personality is founded on the innate temperament. The way of dealing with stress depends on personality traits whose influence is manifested, amongst other things, in the selection of specific coping styles. The current study aim to examine the level of correlation between personality and temperamental traits with manifested coping styles. The study covered 58 volunteers – male fire brigade officers. The following tools were used: Personality Inventory, NEO-FFI, Formal Characteristics of Behaviour: Temperament Inventory – Revised Version, FCZ-KT (R and Coping Inventory for Stressful Situations, CISS. Emotion-focused coping style for stressful situations correlates with the following traits: positively, with perseveration (r=0.5115 and with emotional reactivity (r=0.4927, and negatively, with briskness (r=-0.3926 and endurance (r=-0.5408. The task-oriented coping style for stressful situations correlates positively with extraversion (r=0.3236 and conscientiousness (r=0.3088, and negatively with neuroticism (r=-0.3368 in the NEO-FFI. The emotion-focused coping style for stressful situations is positively correlated with neuroticism (NEO-FFI (r=0.4150. In fire brigade officers, As far as personality traits were concerned, fire brigade officers scored relatively high in extraversion, conscientiousness and low in neuroticism and were likely to demonstrate the task-oriented coping style for stressful situations. Lower level of perseveration and high level of briskness and endurance were associated with emotion-focused coping style for stressful situations. Similarly, the tendency to focus on emotions experienced in stressful situations were associated with high level of neuroticism in the study group.

  11. Soliton dynamics in periodic system with different nonlinear media

    International Nuclear Information System (INIS)

    Zabolotskij, A.A.

    2001-01-01

    To analyze pulse dynamics in the optical system consisting of periodic sequence of nonlinear media one uses a composition model covering a model of resonance interaction of light ultrashort pulse with energy transition of medium with regard to pumping of the upper level and quasi-integrable model describing propagation of light field in another medium with cubic nonlinearity and dispersion. One additionally takes account of losses and other types of interaction in the from of perturbation members. On the basis of the method of scattering back problem and perturbation theory one developed a simple method to study peculiarities of soliton evolution in such periodic system. Due to its application one managed to describe different modes of soliton evolution in such a system including chaotic dynamics [ru

  12. Research on Dynamic Dissolving Model and Experiment for Rock Salt under Different Flow Conditions

    Directory of Open Access Journals (Sweden)

    Xinrong Liu

    2015-01-01

    Full Text Available Utilizing deep rock salt cavern is not only a widely recognized energy reserve method but also a key development direction for implementing the energy strategic reserve plan. And rock salt cavern adopts solution mining techniques to realize building cavity. In view of this, the paper, based on the dissolving properties of rock salt, being simplified and hypothesized the dynamic dissolving process of rock salt, combined conditions between dissolution effect and seepage effect in establishing dynamic dissolving models of rock salt under different flow quantities. Devices were also designed to test the dynamic dissolving process for rock salt samples under different flow quantities and then utilized the finite-difference method to find the numerical solution of the dynamic dissolving model. The artificial intelligence algorithm, Particle Swarm Optimization algorithm (PSO, was finally introduced to conduct inverse analysis of parameters on the established model, whose calculation results coincide with the experimental data.

  13. Time-Domain Nuclear Magnetic Resonance Investigation of Water Dynamics in Different Ginger Cultivars.

    Science.gov (United States)

    Huang, Chongyang; Zhou, Qi; Gao, Shan; Bao, Qingjia; Chen, Fang; Liu, Chaoyang

    2016-01-20

    Different ginger cultivars may contain different nutritional and medicinal values. In this study, a time-domain nuclear magnetic resonance method was employed to study water dynamics in different ginger cultivars. Significant differences in transverse relaxation time T2 values assigned to the distribution of water in different parts of the plant were observed between Henan ginger and four other ginger cultivars. Ion concentration and metabolic analysis showed similar differences in Mn ion concentrations and organic solutes among the different ginger cultivars, respectively. On the basis of Pearson's correlation analysis, many organic solutes and 6-gingerol, the main active substance of ginger, exhibited significant correlations with water distribution as determined by NMR T2 relaxation, suggesting that the organic solute differences may impact water distribution. Our work demonstrates that low-field NMR relaxometry provides useful information about water dynamics in different ginger cultivars as affected by the presence of different organic solutes.

  14. Successful emotion regulation is predicted by amygdala activity and aspects of personality: A latent variable approach.

    Science.gov (United States)

    Morawetz, Carmen; Alexandrowicz, Rainer W; Heekeren, Hauke R

    2017-04-01

    The experience of emotions and their cognitive control are based upon neural responses in prefrontal and subcortical regions and could be affected by personality and temperamental traits. Previous studies established an association between activity in reappraisal-related brain regions (e.g., inferior frontal gyrus and amygdala) and emotion regulation success. Given these relationships, we aimed to further elucidate how individual differences in emotion regulation skills relate to brain activity within the emotion regulation network on the one hand, and personality/temperamental traits on the other. We directly examined the relationship between personality and temperamental traits, emotion regulation success and its underlying neuronal network in a large sample (N = 82) using an explicit emotion regulation task and functional MRI (fMRI). We applied a multimethodological analysis approach, combing standard activation-based analyses with structural equation modeling. First, we found that successful downregulation is predicted by activity in key regions related to emotion processing. Second, the individual ability to successfully upregulate emotions is strongly associated with the ability to identify feelings, conscientiousness, and neuroticism. Third, the successful downregulation of emotion is modulated by openness to experience and habitual use of reappraisal. Fourth, the ability to regulate emotions is best predicted by a combination of brain activity and personality as well temperamental traits. Using a multimethodological analysis approach, we provide a first step toward a causal model of individual differences in emotion regulation ability by linking biological systems underlying emotion regulation with descriptive constructs. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  15. Adaptive synchronization between two different order and topology dynamical systems

    International Nuclear Information System (INIS)

    Bowong, S.; Moukam Kakmeni, F.M.; Yamapi, R.

    2006-07-01

    This contribution studies adaptive synchronization between two dynamical systems of different order whose topological structure is also different. By order we mean the number of first order differential equations. The problem is closely related to the synchronization of strictly different systems. The master system is given by a sixth order equation with chaotic behavior whereas the slave system is a fourth-order nonautonomous with rational nonlinear terms. Based on the Lyapunov stability theory, sufficient conditions for the synchronization have been analyzed theoretically and numerically. (author)

  16. Metabolic syndrome prevalence in different affective temperament profiles in bipolar-I disorder

    Directory of Open Access Journals (Sweden)

    Kursat Altinbas

    2013-06-01

    Full Text Available Objective: Temperament originates in the brain structure, and individual differences are attributable to neural and physiological function differences. It has been suggested that temperament is associated with metabolic syndrome (MetS markers, which may be partly mediated by lifestyle and socioeconomic status. Therefore, we aim to compare MetS prevalence between different affective temperamental profiles for each season in bipolar patients. Methods: Twenty-six bipolar type-I patients of a specialized outpatient mood disorder unit were evaluated for MetS according to new definition proposed by the International Diabetes Federation in the four seasons of a year. Temperament was assessed using the Temperament Evaluation of Memphis, Pisa, Paris and San Diego - autoquestionnaire version (TEMPS-A. Results: The proportions of MetS were 19.2, 23.1, 34.6, and 38.5% in the summer, fall, spring, and winter, respectively. Only depressive temperament scores were higher (p = 0.002 during the winter in patients with MetS. Conclusion: These data suggest that depressive temperament profiles may predispose an individual to the development of MetS in the winter.

  17. The computation of dynamic fractional difference parameter for S&P500 index

    Science.gov (United States)

    Pei, Tan Pei; Cheong, Chin Wen; Galagedera, Don U. A.

    2015-10-01

    This study evaluates the time-varying long memory behaviors of the S&P500 volatility index using dynamic fractional difference parameters. Time-varying fractional difference parameter shows the dynamic of long memory in volatility series for the pre and post subprime mortgage crisis triggered by U.S. The results find an increasing trend in the S&P500 long memory volatility for the pre-crisis period. However, the onset of Lehman Brothers event reduces the predictability of volatility series following by a slight fluctuation of the factional differencing parameters. After that, the U.S. financial market becomes more informationally efficient and follows a non-stationary random process.

  18. The link between infant regulatory problems, temperament traits, maternal depressive symptoms and children's psychopathological symptoms at age three: a longitudinal study in a German at-risk sample.

    Science.gov (United States)

    Sidor, Anna; Fischer, Cristina; Cierpka, Manfred

    2017-01-01

    Difficult conditions during childhood can limit an individual's development in many ways. Factors such as being raised in an at-risk family, child temperamental traits or maternal traits can potentially influence a child's later behaviour. The present study investigated the extent of regulatory problems in 6-month-old infants and their link to temperamental traits and impact on externalizing and internalizing problems at 36 months. Moderating effects of maternal distress and maternal depressive symptoms were tested as well. In a quasi-experimental, longitudinal study, a sample of 185 mother-infant dyads at psychosocial risk was investigated at 6 months with SFS (infants' regulatory problems) and at 3 years with CBCL (children's behavioural problems), EAS (children's temperament), ADS (maternal depressive symptoms) and PSI-SF (maternal stress). A hierarchical regression analysis yielded a significant association between infants' regulatory problems and both externalizing and internalizing behaviour problems at age 3 (accounting for 16% and 14% variance), with both externalizing and internalizing problems being linked to current maternal depressive symptoms (12 and 9% of the variance). Externalizing and internalizing problems were found to be related also to children's temperamental difficulty (18 and 13% of variance) and their negative emotionality. With temperamental traits having been taken into account, only feeding problems at 6 months contributed near-significant to internalizing problems at 3 years. Our results underscore the crucial role of temperament in the path between early regulatory problems and subsequent behavioural difficulties. Children's unfavourable temperamental predispositions such as negative emotionality and generally "difficult temperament" contributed substantially to both externalizing and internalizing behavioural problems in the high-risk sample. The decreased predictive power of regulatory problems following the inclusion of

  19. Solution strategies as possible explanations of individual and sex differences in a dynamic spatial task.

    Science.gov (United States)

    Peña, Daniel; Contreras, María José; Shih, Pei Chun; Santacreu, José

    2008-05-01

    When individuals perform spatial tasks, individual differences emerge in accuracy and speed as well as in the response patterns used to cope with the task. The purpose of this study is to identify, through empirical criteria, the different response patterns or strategies used by individuals when performing the dynamic spatial task presented in the Spatial Orientation Dynamic Test-Revised (SODT-R). Results show that participants can be classified according to their response patterns. Three different ways of solving a task are described, and their relation to (a) performance factors (response latency, response frequency, and invested time) and (b) ability tests (analytical reasoning, verbal reasoning, and spatial estimation) are investigated. Sex differences in response patterns and performance are also analyzed. It is found that the frequency with which men and women employ each one of the strategies described here, is different and statistically significant. Thus, employed strategy plays an important role when interpreting sex differences on dynamic spatial tasks.

  20. Economy, Movement Dynamics, and Muscle Activity of Human Walking at Different Speeds

    DEFF Research Database (Denmark)

    Raffalt, Peter Christian; Guul, Martin Kjær; Nielsen, A. N.

    2017-01-01

    The complex behaviour of human walking with respect to movement variability, economy and muscle activity is speed dependent. It is well known that a U-shaped relationship between walking speed and economy exists. However, it is an open question if the movement dynamics of joint angles and centre...... of mass and muscle activation strategy also exhibit a U-shaped relationship with walking speed. We investigated the dynamics of joint angle trajectories and the centre of mass accelerations at five different speeds ranging from 20 to 180% of the predicted preferred speed (based on Froude speed) in twelve...... healthy males. The muscle activation strategy and walking economy were also assessed. The movement dynamics was investigated using a combination of the largest Lyapunov exponent and correlation dimension. We observed an intermediate stage of the movement dynamics of the knee joint angle and the anterior...

  1. Comparison of Static and Dynamic Elastic Modules of Different Strength Concretes

    Science.gov (United States)

    Uyanık, Osman; Sabbaǧ, Nevbahar

    2016-04-01

    In this study, the static and dynamic elastic (Young) modules of concrete with different strength was intended to compare. For this purpose 150mm dimensions 9 for each design cubic samples prepared and they were subjected to water cure during 28 days. After Seismic Ultrasonic P and S wave travel time measurements of samples, P and S wave velocities and taking advantage of elasticity theory the dynamic elastic modules were calculated. Concrete strength was obtained from the uniaxial compression tests in order to calculate the static elastic modules of the samples. The static elastic modulus is calculated by using the empirical relationships used in international standards. The obtained static and dynamic elastic modules have been associated. A curve was obtained from this association result that approximately similar to the stress-strain curve of obtaining at failure criterion of the sample. This study was supported with OYP05277-DR-14 Project No. by SDU and State Hydraulic Works 13th Regional/2012-01 Project No. Keywords: Concrete Strength, P and S wave Velocities, Static, Dynamic, Young Modules

  2. Water dynamics in different biochar fractions.

    Science.gov (United States)

    Conte, Pellegrino; Nestle, Nikolaus

    2015-09-01

    Biochar is a carbonaceous porous material deliberately applied to soil to improve its fertility. The mechanisms through which biochar acts on fertility are still poorly understood. The effect of biochar texture size on water dynamics was investigated here in order to provide information to address future research on nutrient mobility towards plant roots as biochar is applied as soil amendment. A poplar biochar has been stainless steel fractionated in three different textured fractions (1.0-2.0 mm, 0.3-1.0 mm and <0.3 mm, respectively). Water-saturated fractions were analyzed by fast field cycling (FFC) NMR relaxometry. Results proved that 3D exchange between bound and bulk water predominantly occurred in the coarsest fraction. However, as porosity decreased, water motion was mainly associated to a restricted 2D diffusion among the surface-site pores and the bulk-site ones. The X-ray μ-CT imaging analyses on the dry fractions revealed the lowest surface/volume ratio for the coarsest fraction, thereby corroborating the 3D water exchange mechanism hypothesized by FFC NMR relaxometry. However, multi-micrometer porosity was evidenced in all the samples. The latter finding suggested that the 3D exchange mechanism cannot even be neglected in the finest fraction as previously excluded only on the basis of NMR relaxometry results. X-ray μ-CT imaging showed heterogeneous distribution of inorganic materials inside all the fractions. The mineral components may contribute to the water relaxation mechanisms by FFC NMR relaxometry. Further studies are needed to understand the role of the inorganic particles on water dynamics. Copyright © 2015 John Wiley & Sons, Ltd.

  3. Comparison of erythrocyte dynamics in shear flow under different stress-free configurations

    Science.gov (United States)

    Cordasco, Daniel; Yazdani, Alireza; Bagchi, Prosenjit

    2014-04-01

    An open question that has persisted for decades is whether the cytoskeleton of a red blood cell is stress-free or under a stress. This question is important in the context of theoretical modeling of cellular motion under a flowing condition where it is necessary to make an assumption about the stress-free state. Here, we present a 3D numerical study to compare the cell dynamics in a simple shear flow under two different stress-free states, a biconcave discocyte representing the resting shape of the cell, and a nearly spherical oblate shape. We find that whether the stress-free states make a significant difference or not depends on the viscosity of the suspending medium. If the viscosity is close to that of blood plasma, the two stress-free states do not show any significant difference in cell dynamics. However, when the suspending medium viscosity is well above that of the physiological range, as in many in vitro studies, the shear rate separating the tank-treading and tumbling dynamics is observed to be higher for the biconcave stress-free state than the spheroidal state. The former shows a strong shape oscillation with repeated departures from the biconcave shape, while the latter shows a nearly stable biconcave shape. It is found that the cell membrane in the biconcave stress-free state is under a compressive stress and a weaker bending force density, leading to a periodic compression of the cell. The shape oscillation then leads to a higher energy barrier against membrane tank-tread leading to an early transition to tumbling. However, if the cells are released with a large off-shear plane angle, the oscillations can be suppressed due to an azimuthal motion of the membrane along the vorticity direction leading to a redistribution of the membrane points and lowering of the energy barrier, which again results in a nearly similar behavior of the cells under the two different stress-free states. A variety of off-shear plane dynamics is observed, namely, rolling

  4. Transient hepatic attenuation difference of lobar or segmental distribution detected by dynamic computed tomography

    International Nuclear Information System (INIS)

    Itai, Y.; Moss, A.A.; Goldberg, H.I.

    1982-01-01

    Dynamic computed tomography of hepatic tumors revealed a transient attenuation difference of the liver in a lobar or segmental distribution in three cases. The difference was most prominent during the hepatogram phase. It was attributed to siphonage of arterial blood by hepatic tumors in two cases, while an increase of arterial flow induced by portal vein occlusion was inferred in the other case. Results indicate dynamic computed tomography will be usful in analysis of geometrical hemodynamics

  5. Dynamics of the plasma current sheath in plasma focus discharges in different gases

    Energy Technology Data Exchange (ETDEWEB)

    Vinogradov, V. P.; Krauz, V. I., E-mail: krauz-vi@nrcki.ru [National Research Center Kurchatov Institute (Russian Federation); Mokeev, A. N. [Project Center ITER (Russian Federation); Myalton, V. V.; Kharrasov, A. M. [National Research Center Kurchatov Institute (Russian Federation)

    2016-12-15

    The shape of the plasma current sheath (PCS) in the final stage of its radial compression, the dynamics of pinching, and the subsequent pinch decay in plasma focus (PF) discharges in different gases are studied using an improved multichannel system of electron-optical plasma photography and a newly elaborated synchronization system. The PCS structure in discharges in heavy gases (Ne, Ar) is found to differ significantly from that in discharges in hydrogen and deuterium. The influence of a heavy gas (Xe) additive to hydrogen and deuterium on the structure and compression dynamics of the PCS is investigated.

  6. FACTORS OF THE EMERGENCE OF INTRAPERSONAL CONFLICT AMONG STUDENTS

    Directory of Open Access Journals (Sweden)

    Polina Alexandrovna Kukso

    2017-11-01

    Full Text Available Purpose. The article deals with the problem of intrapersonal conflict among students in the period of their professional development. Students are in the period of youth, which is critical in the psychological development periodization system. The aim of this research is to reveal connection between intrapersonal conflict and some of the temperamental measures among students, on the one hand, and between intrapersonal conflict and the temperamental measures depending on sex, on the other hand. Methodology. In the work was used Fantalova’s method method «The level of correlation of value and accessibility in different spheres of life», the temperament research questionnaire by J. Strelau, the personal questionnaire EPI (Eysenck Personality Inventory, Spilberger anxiety scale. Results. Three groups of students with a different type of intrapersonal conflict were distinguished. Based on the data obtained, some types of intrapersonal conflict reflecting peculiarities of intrapersonal antagonism of the young people studying in higher education institutions were singled out. A comparative analysis of temperamental and personal measures of students from these groups was conducted. Practical implications. The study of intrapersonal conflict of students and the development of psychological protection is an important scientific and practical problem for the organization of the educational process.

  7. Dynamic functional connectivity and individual differences in emotions during social stress.

    Science.gov (United States)

    Tobia, Michael J; Hayashi, Koby; Ballard, Grey; Gotlib, Ian H; Waugh, Christian E

    2017-12-01

    Exposure to acute stress induces multiple emotional responses, each with their own unique temporal dynamics. Dynamic functional connectivity (dFC) measures the temporal variability of network synchrony and captures individual differences in network neurodynamics. This study investigated the relationship between dFC and individual differences in emotions induced by an acute psychosocial stressor. Sixteen healthy adult women underwent fMRI scanning during a social evaluative threat (SET) task, and retrospectively completed questionnaires that assessed individual differences in subjectively experienced positive and negative emotions about stress and stress relief during the task. Group dFC was decomposed with parallel factor analysis (PARAFAC) into 10 components, each with a temporal signature, spatial network of functionally connected regions, and vector of participant loadings that captures individual differences in dFC. Participant loadings of two networks were positively correlated with stress-related emotions, indicating the existence of networks for positive and negative emotions. The emotion-related networks involved the ventromedial prefrontal cortex, cingulate cortex, anterior insula, and amygdala, among other distributed brain regions, and time signatures for these emotion-related networks were uncorrelated. These findings demonstrate that individual differences in stress-induced positive and negative emotions are each uniquely associated with large-scale brain networks, and suggest that dFC is a mechanism that generates individual differences in the emotional components of the stress response. Hum Brain Mapp 38:6185-6205, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  8. The lie-algebraic structures and integrability of differential and differential-difference nonlinear dynamical systems

    International Nuclear Information System (INIS)

    Prykarpatsky, A.K.; Blackmore, D.L.; Bogolubov, N.N. Jr.

    2007-05-01

    The infinite-dimensional operator Lie algebras of the related integrable nonlocal differential-difference dynamical systems are treated as their hidden symmetries. As a result of their dimerization the Lax type representations for both local differential-difference equations and nonlocal ones are obtained. An alternative approach to the Lie-algebraic interpretation of the integrable local differential-difference systems is also proposed. The Hamiltonian representation for a hierarchy of Lax type equations on a dual space to the centrally extended Lie algebra of integro-differential operators with matrix-valued coefficients coupled with suitable eigenfunctions and adjoint eigenfunctions evolutions of associated spectral problems is obtained by means of a specially constructed Baecklund transformation. The Hamiltonian description for the corresponding set of additional symmetry hierarchies is represented. The relation of these hierarchies with Lax type integrable (3+1)-dimensional nonlinear dynamical systems and their triple Lax type linearizations is analyzed. The Lie-algebraic structures, related with centrally extended current operator Lie algebras are discussed with respect to constructing new nonlinear integrable dynamical systems on functional manifolds and super-manifolds. Special Poisson structures and related with them factorized integrable operator dynamical systems having interesting applications in modern mathematical physics, quantum computing mathematics and other fields are constructed. The previous purely computational results are explained within the approach developed. (author)

  9. A Dynamical System Approach Explaining the Process of Development by Introducing Different Time-scales.

    Science.gov (United States)

    Hashemi Kamangar, Somayeh Sadat; Moradimanesh, Zahra; Mokhtari, Setareh; Bakouie, Fatemeh

    2018-06-11

    A developmental process can be described as changes through time within a complex dynamic system. The self-organized changes and emergent behaviour during development can be described and modeled as a dynamical system. We propose a dynamical system approach to answer the main question in human cognitive development i.e. the changes during development happens continuously or in discontinuous stages. Within this approach there is a concept; the size of time scales, which can be used to address the aforementioned question. We introduce a framework, by considering the concept of time-scale, in which "fast" and "slow" is defined by the size of time-scales. According to our suggested model, the overall pattern of development can be seen as one continuous function, with different time-scales in different time intervals.

  10. Excimer Formation Dynamics of Dipyrenyldecane in Structurally Different Ionic Liquids.

    Science.gov (United States)

    Yadav, Anita; Pandey, Siddharth

    2017-12-07

    Ionic liquids, being composed of ions alone, may offer alternative pathways for molecular aggregation. These pathways could be controlled by the chemical structure of the cation and the anion of the ionic liquids. Intramolecular excimer formation dynamics of a bifluorophoric probe, 1,3-bis(1-pyrenyl)decane [1Py(10)1Py], where the fluorophoric pyrene moieties are separated by a long decyl chain, is investigated in seven different ionic liquids in 10-90 °C temperature range. The long alkyl separator allows for ample interaction with the solubilizing milieu prior to the formation of the excimer. The ionic liquids are composed of two sets, one having four ionic liquids of 1-butyl-3-methylimidazolium cation ([bmim + ]) with different anions and the other having four ionic liquids of bis(trifluoromethylsulfonyl)imide anion ([Tf 2 N - ]) with different cations. The excimer-to-monomer emission intensity ratio (I E /I M ) is found to increase with increasing temperature in sigmoidal fashion. Chemical structure of the ionic liquid controls the excimer formation efficiency, as I E /I M values within ionic liquids with the same viscosities are found to be significantly different. The excited-state intensity decay kinetics of 1Py(10)1Py in ionic liquids do not adhere to a simplistic Birk's scheme, where only one excimer conformer forms after excitation. The apparent rate constants of excimer formation (k a ) in highly viscous ionic liquids are an order of magnitude lower than those reported in organic solvents. In general, the higher the viscosity of the ionic liquid, the more sensitive is the k a to the temperature with higher activation energy, E a . The trend in E a is found to be similar to that for activation energy of the viscous flow (E a,η ). Stokes-Einstein relationship is not followed in [bmim + ] ionic liquids; however, with the exception of [choline][Tf 2 N], it is found to be followed in [Tf 2 N - ] ionic liquids suggesting the cyclization dynamics of 1Py(10)1Py

  11. Perturbation of whole-brain dynamics in silico reveals mechanistic differences between brain states

    NARCIS (Netherlands)

    Deco, Gustavo; Cabral, Joana; Saenger, Victor M; Boly, Melanie; Tagliazucchi, Enzo; Laufs, Helmut; Van Someren, Eus; Jobst, Beatrice; Stevner, Angus; Kringelbach, Morten L

    2017-01-01

    Human neuroimaging research has revealed that wakefulness and sleep involve very different activity patterns. Yet, it is not clear why brain states differ in their dynamical complexity, e.g. in the level of integration and segregation across brain networks over time. Here, we investigate the

  12. Perturbation of whole-brain dynamics in silico reveals mechanistic differences between brain states

    NARCIS (Netherlands)

    Deco, Gustavo; Cabral, Joana; Saenger, Victor M; Boly, Melanie; Tagliazucchi, Enzo; Laufs, Helmut; Van Someren, Eus; Jobst, Beatrice M; Stevner, Angus B A; Kringelbach, Morten L

    2018-01-01

    Human neuroimaging research has revealed that wakefulness and sleep involve very different activity patterns. Yet, it is not clear why brain states differ in their dynamical complexity, e.g. in the level of integration and segregation across brain networks over time. Here, we investigate the

  13. Finite difference evolution equations and quantum dynamical semigroups

    International Nuclear Information System (INIS)

    Ghirardi, G.C.; Weber, T.

    1983-12-01

    We consider the recently proposed [Bonifacio, Lett. Nuovo Cimento, 37, 481 (1983)] coarse grained description of time evolution for the density operator rho(t) through a finite difference equation with steps tau, and we prove that there exists a generator of the quantum dynamical semigroup type yielding an equation giving a continuous evolution coinciding at all time steps with the one induced by the coarse grained description. The map rho(0)→rho(t) derived in this way takes the standard form originally proposed by Lindblad [Comm. Math. Phys., 48, 119 (1976)], even when the map itself (and, therefore, the corresponding generator) is not bounded. (author)

  14. Dynamic postural stability differences between male and female players with and without ankle sprain

    NARCIS (Netherlands)

    Dallinga, Joan M.; Does, van der Henrike T. D.; Benjaminse, Anne; Lemmink, Koen A. P. M.

    Objectives: To evaluate dynamic stability index (DSI) differences between males and females for different jump directions. To examine both preseason DSI differences between players with and without a history of ankle sprain, and between players with and without an ankle sprain during the subsequent

  15. The coupled dynamical problem of thermoelasticity in case of large temperature differences

    International Nuclear Information System (INIS)

    Szekeres, A.

    1981-01-01

    In the tasks of thermoelasticity in general, also in dynamical problems it is common to suppose small temperature differences. The equations used in scientific literature refer to these. It arises the thought of what is the influence on the dynamical problems of taking into account the large temperature changes. To investigate this first we present the general equation of heat conduction in case of small temperature differences according to Nowacki and Biot. On this basis we introduce the general equation of heat conduction with large temperature changes. Some remarks show the connection between the two cases. Using the latter in the equations of thermoelasticity we write down the expressions of the problem for the thermal shock of a long bar. Finally we show the results of the numerical example and the experimental opoortunity to measure some of the constants. (orig.)

  16. Genetically different isolates of Trypanosoma cruzi elicit different infection dynamics in raccoons (Procyon lotor) and Virginia opossums (Didelphis virginiana).

    Science.gov (United States)

    Roellig, Dawn M; Ellis, Angela E; Yabsley, Michael J

    2009-12-01

    Trypanosoma cruzi is a genetically and biologically diverse species. In the current study we determined T. cruzi infection dynamics in two common North American reservoirs, Virginia opossums (Didelphis virginiana) and raccoons (Procyon lotor). Based on previous molecular and culture data from naturally-exposed animals, we hypothesised that raccoons would have a longer patent period than opossums, and raccoons would be competent reservoirs for both genotypes T. cruzi I (TcI) and TcIIa, while opossums would only serve as hosts for TcI. Individuals (n=2 or 3) of each species were inoculated with 1x10(6) culture-derived T. cruzi trypomastigotes of TcIIa (North American (NA) - raccoon), TcI (NA - opossum), TcIIb (South American - human), or both TcI and TcIIa. Parasitemias in opossums gradually increased and declined rapidly, whereas parasitemias peaked sooner in raccoons and they maintained relatively high parasitemia for 5weeks. Raccoons became infected with all three T. cruzi strains, while opossums only became infected with TcI and TcIIb. Although opossums were susceptible to TcIIb, infection dynamics were dramatically different compared with TcI. Opossums inoculated with TcIIb seroconverted, but parasitemia duration was short and only detectable by PCR. In addition, raccoons seroconverted sooner (3-7days post inoculation) than opossums (10days post inoculation). These data suggest that infection dynamics of various T. cruzi strains can differ considerably in different wildlife hosts.

  17. Differences in Dynamic Brand Competition Across Markets: An Empirical Analysis

    OpenAIRE

    Jean-Pierre Dubé; Puneet Manchanda

    2005-01-01

    We investigate differences in the dynamics of marketing decisions across geographic markets empirically. We begin with a linear-quadratic game involving forward-looking firms competing on prices and advertising. Based on the corresponding Markov perfect equilibrium, we propose estimable econometric equations for demand and marketing policy. Our model allows us to measure empirically the strategic response of competitors along with economic measures such as firm profitability. We use a rich da...

  18. Cluster dynamics at different cluster size and incident laser wavelengths

    International Nuclear Information System (INIS)

    Desai, Tara; Bernardinello, Andrea

    2002-01-01

    X-ray emission spectra from aluminum clusters of diameter -0.4 μm and gold clusters of dia. ∼1.25 μm are experimentally studied by irradiating the cluster foil targets with 1.06 μm laser, 10 ns (FWHM) at an intensity ∼10 12 W/cm 2 . Aluminum clusters show a different spectra compared to bulk material whereas gold cluster evolve towards bulk gold. Experimental data are analyzed on the basis of cluster dimension, laser wavelength and pulse duration. PIC simulations are performed to study the behavior of clusters at higher intensity I≥10 17 W/cm 2 for different size of the clusters irradiated at different laser wavelengths. Results indicate the dependence of cluster dynamics on cluster size and incident laser wavelength

  19. Dynamics expansion of laser produced plasma with different materials in magnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Rabia Qindeel; Noriah Bte Bidin; Yaacob Mat daud [Laser Technology Laboratory, Physics Department, Universiti Teknologi Malaysia, Skudai 81310, Johor (Malaysia)], E-mail: plasmaqindeel@yahoo.com

    2008-12-01

    The dynamics expansion of the plasma generated by laser ablation of different materials has been investigated. The dynamics and confinement of laser generated plasma plumes are expanding across variable magnetic fields. A Q-switched neodymium-doped yttrium aluminum garnet laser with 1064 nm, 8 ns pulse width and 0.125 J laser energy was used to generate plasma that was allowed to expand across variable magnetic within 0.1 - 0.8 T. The expansions of laser-produced plasma of different materials are characterized by using constant laser power. CCD video camera was used to visualize and record the activities in the focal region. The plasma plume length, width and area were measured by using Matrox Inpector 2.1 and video Test 0.5 software. Spectrums of plasma beam from different materials are studied via spectrometer. The results show that the plasma generated by aluminum target is the largest than Brass and copper. The optical radiation from laser generated plasma beam spectrums are obtained in the range of UV to visible light.

  20. Differences of muscle co-contraction of the ankle joint between young and elderly adults during dynamic postural control at different speeds.

    Science.gov (United States)

    Iwamoto, Yoshitaka; Takahashi, Makoto; Shinkoda, Koichi

    2017-08-02

    Agonist and antagonist muscle co-contractions during motor tasks are greater in the elderly than in young adults. During normal walking, muscle co-contraction increases with gait speed in young adults, but not in elderly adults. However, no study has compared the effects of speed on muscle co-contraction of the ankle joint during dynamic postural control in young and elderly adults. We compared muscle co-contractions of the ankle joint between young and elderly subjects during a functional stability boundary test at different speeds. Fifteen young adults and 16 community-dwelling elderly adults participated in this study. The task was functional stability boundary tests at different speeds (preferred and fast). Electromyographic evaluations of the tibialis anterior and soleus were recorded. The muscle co-contraction was evaluated using the co-contraction index (CI). There were no statistically significant differences in the postural sway parameters between the two age groups. Elderly subjects showed larger CI in both speed conditions than did the young subjects. CI was higher in the fast speed condition than in the preferred speed condition in the young subjects, but there was no difference in the elderly subjects. Moreover, after dividing the analytical range into phases (acceleration and deceleration phases), the CI was larger in the deceleration phase than in the acceleration phase in both groups, except for the young subjects in the fast speed conditions. Our results showed a greater muscle co-contraction of the ankle joint during dynamic postural control in elderly subjects than in young subjects not only in the preferred speed condition but also in the fast speed condition. In addition, the young subjects showed increased muscle co-contraction in the fast speed condition compared with that in the preferred speed condition; however, the elderly subjects showed no significant difference in muscle co-contraction between the two speed conditions. This indicates

  1. Temperament Theory and the Study of Cognition-Emotion Interactions across Development

    Science.gov (United States)

    Henderson, Heather A.; Wachs, Theodore D.

    2007-01-01

    In this paper we review current definitions and measurement approaches used to assess individual differences in children's temperament. We review the neural bases of temperamental reactivity and self-regulation and propose that these constructs provide a framework for examining individual differences and developmental change in emotion-cognition…

  2. Dynamic Dipole-Dipole Interactions between Excitons in Quantum Dots of Different Sizes

    DEFF Research Database (Denmark)

    Matsueda, Hideaki; Leosson, Kristjan; Xu, Zhangcheng

    2005-01-01

    Micro-photoluminescence spectra of GaAs/AlGaAs coupled quantum dots (QDs) are given, and proposed to be analyzed by our resonance dynamic dipole-dipole interaction (RDDDI) model, based on parity inheritance and exchange of virtual photons among QDs of different sizes....

  3. Outer synchronization between two different fractional-order general complex dynamical networks

    International Nuclear Information System (INIS)

    Xiang-Jun, Wu; Hong-Tao, Lu

    2010-01-01

    Outer synchronization between two different fractional-order general complex dynamical networks is investigated in this paper. Based on the stability theory of the fractional-order system, the sufficient criteria for outer synchronization are derived analytically by applying the nonlinear control and the bidirectional coupling methods. The proposed synchronization method is applicable to almost all kinds of coupled fractional-order general complex dynamical networks. Neither a symmetric nor irreducible coupling configuration matrix is required. In addition, no constraint is imposed on the inner-coupling matrix. Numerical examples are also provided to demonstrate the validity of the presented synchronization scheme. Numeric evidence shows that both the feedback strength k and the fractional order α can be chosen appropriately to adjust the synchronization effect effectively. (general)

  4. Similar but Different: Dynamic Social Network Analysis Highlights Fundamental Differences between the Fission-Fusion Societies of Two Equid Species, the Onager and Grevy's Zebra.

    Directory of Open Access Journals (Sweden)

    Daniel I Rubenstein

    Full Text Available Understanding why animal societies take on the form that they do has benefited from insights gained by applying social network analysis to patterns of individual associations. Such analyses typically aggregate data over long time periods even though most selective forces that shape sociality have strong temporal elements. By explicitly incorporating the temporal signal in social interaction data we re-examine the network dynamics of the social systems of the evolutionarily closely-related Grevy's zebras and wild asses that show broadly similar social organizations. By identifying dynamic communities, previously hidden differences emerge: Grevy's zebras show more modularity than wild asses and in wild asses most communities consist of solitary individuals; and in Grevy's zebras, lactating females show a greater propensity to switch communities than non-lactating females and males. Both patterns were missed by static network analyses and in general, adding a temporal dimension provides insights into differences associated with the size and persistence of communities as well as the frequency and synchrony of their formation. Dynamic network analysis provides insights into the functional significance of these social differences and highlights the way dynamic community analysis can be applied to other species.

  5. Childhood temperament predictors of adolescent physical activity

    Directory of Open Access Journals (Sweden)

    James A Janssen

    2017-01-01

    Full Text Available Abstract Background Physical inactivity is a leading cause of mortality worldwide. Many patterns of physical activity involvement are established early in life. To date, the role of easily identifiable early-life individual predictors of PA, such as childhood temperament, remains relatively unexplored. Here, we tested whether childhood temperamental activity level, high intensity pleasure, low intensity pleasure, and surgency predicted engagement in physical activity (PA patterns 11 years later in adolescence. Methods Data came from a longitudinal community study (N = 206 participants, 53% females, 70% Caucasian. Parents reported their children’s temperamental characteristics using the Child Behavior Questionnaire (CBQ when children were 4 & 5 years old. Approximately 11 years later, adolescents completed self-reports of PA using the Godin Leisure Time Exercise Questionnaire and the Youth Risk Behavior Survey. Ordered logistic regression, ordinary least squares linear regression, and Zero-inflated Poisson regression models were used to predict adolescent PA from childhood temperament. Race, socioeconomic status, and adolescent body mass index were used as covariates. Results Males with greater childhood temperamental activity level engaged in greater adolescent PA volume (B = .42, SE = .13 and a 1 SD difference in childhood temperamental activity level predicted 29.7% more strenuous adolescent PA per week. Males’ high intensity pleasure predicted higher adolescent PA volume (B = .28, SE = .12. Males’ surgency positively predicted more frequent PA activity (B = .47, SE = .23, OR = 1.61, 95% CI: 1.02, 2.54 and PA volume (B = .31, SE = .12. No predictions from females’ childhood temperament to later PA engagement were identified. Conclusions Childhood temperament may influence the formation of later PA habits, particularly in males. Boys with high temperamental activity level, high intensity

  6. Nonlinear Dynamics in a Cournot Duopoly with Different Attitudes towards Strategic Uncertainty

    Directory of Open Access Journals (Sweden)

    Luciano Fanti

    2013-01-01

    Full Text Available This paper analyses the dynamics of a duopoly with quantity-setting firms and different attitudes towards strategic uncertainty. By following the recent literature on decision making under uncertainty, where the Choquet expected utility theory is adopted to allow firms to plan their strategies, we investigate the effects of the interaction between pessimistic and optimistic firms on economic dynamics described by a two-dimensional map. In particular, the study of the local and global behaviour of the map is performed under three assumptions: (1 both firms have complete information on the market demand and adjust production over time depending on past behaviours (static expectations—“best reply” dynamics; (2 both firms have incomplete information and production is adjusted over time by following a mechanism based on marginal profits; and (3 one firm has incomplete information on the market demand and production decisions are based on the behaviour of marginal profits, and the rival has complete information on the market demand and static expectations. In cases 2 and 3 it is shown that complex dynamics and coexistence of attractors may arise. The analysis is carried forward through numerical simulations and the critical lines technique.

  7. Input-output relation and energy efficiency in the neuron with different spike threshold dynamics.

    Science.gov (United States)

    Yi, Guo-Sheng; Wang, Jiang; Tsang, Kai-Ming; Wei, Xi-Le; Deng, Bin

    2015-01-01

    Neuron encodes and transmits information through generating sequences of output spikes, which is a high energy-consuming process. The spike is initiated when membrane depolarization reaches a threshold voltage. In many neurons, threshold is dynamic and depends on the rate of membrane depolarization (dV/dt) preceding a spike. Identifying the metabolic energy involved in neural coding and their relationship to threshold dynamic is critical to understanding neuronal function and evolution. Here, we use a modified Morris-Lecar model to investigate neuronal input-output property and energy efficiency associated with different spike threshold dynamics. We find that the neurons with dynamic threshold sensitive to dV/dt generate discontinuous frequency-current curve and type II phase response curve (PRC) through Hopf bifurcation, and weak noise could prohibit spiking when bifurcation just occurs. The threshold that is insensitive to dV/dt, instead, results in a continuous frequency-current curve, a type I PRC and a saddle-node on invariant circle bifurcation, and simultaneously weak noise cannot inhibit spiking. It is also shown that the bifurcation, frequency-current curve and PRC type associated with different threshold dynamics arise from the distinct subthreshold interactions of membrane currents. Further, we observe that the energy consumption of the neuron is related to its firing characteristics. The depolarization of spike threshold improves neuronal energy efficiency by reducing the overlap of Na(+) and K(+) currents during an action potential. The high energy efficiency is achieved at more depolarized spike threshold and high stimulus current. These results provide a fundamental biophysical connection that links spike threshold dynamics, input-output relation, energetics and spike initiation, which could contribute to uncover neural encoding mechanism.

  8. Shear-wave dynamic behavior using two different orientations

    International Nuclear Information System (INIS)

    Ghassem Alaskari, M. K.; Hashemi, S. J.

    2007-01-01

    For laterally complex media, it may be more suitable to take a different orientation of the displacement vector of Shear-waves. This may change the sign of several imaginary reflections and conversion coefficients to be used in reservoir characterization and Amplitude Versus Offset analysis or modeling. In this new convention the positive direction of the displacement vector of reflected Shear-waves is chosen to the left of ray tangent (in the direction of wave propagation). Therefore, the definition of the displacement vector of shear-waves can be used properly even for very complicated media. Finally the shear-wave dynamic behavior of a reservoir zone can be illustrated for laterally varying structures in terms of the amplitude variation and phase behavior using this new orientation

  9. Dynamic dipole-dipole interactions between excitons in quantum dots of different sizes

    DEFF Research Database (Denmark)

    Matsueda, Hideaki; Leosson, Kristjan; Xu, Zhangcheng

    2004-01-01

    A model of the resonance dynamic dipole-dipole interaction between excitons confined in quantum dots (QDs) of different sizes at close enough distance is given in terms of parity inheritance and exchange of virtual photons. Microphotoluminescence spectra of GaAs-AlGaAs coupled QDs are proposed to...

  10. Effect of differences in gas-dynamic behaviour on the separation performance of ultracentrifuges connected in parallel

    International Nuclear Information System (INIS)

    Portoghese, C.C.P.; Buchmann, J.H.

    1996-01-01

    This paper is concerned with the degradation of separation factors occurred when groups of ultracentrifuges having different gas-dynamic behaviour are connected in parallel arrangements. Differences in the gas-dynamic behavior were traduced in terms of different tails pressures for the same operational conditions, that are feed flow rate, product pressure and cut number. A mathematical model describing the ratio of the tails flow rates as a function of the tails pressure ratios and the feed flow rate was developed using experimental data collected from a pair of different ultracentrifuges connected in parallel. The optimization of model parameters was made using Marquardt's algorithm. The model developed was used to simulate the separation factors degradation in some parallel arrangements containing more than two centrifuges. Te obtained results were compared with experimental data collected from different groups of ultracentrifuges. It was observed that the calculated results were in good agreement with experimental data. This mathematical model, which parameters were determined in a two-centrifuges parallel arrangement, is useful to simulate the effect of quantified gas-dynamic differences in the separation factors of groups containing any number of different ultracentrifuges and, consequently, to analyze cascade losses due to this kind of occurrence. (author)

  11. Current perspectives on the dynamics of antibiotic resistance in different reservoirs.

    Science.gov (United States)

    Caniça, Manuela; Manageiro, Vera; Jones-Dias, Daniela; Clemente, Lurdes; Gomes-Neves, Eduarda; Poeta, Patrícia; Dias, Elsa; Ferreira, Eugénia

    2015-09-01

    Antibiotic resistance consists of a dynamic web. In this review, we describe the path by which different antibiotic residues and antibiotic resistance genes disseminate among relevant reservoirs (human, animal, and environmental settings), evaluating how these events contribute to the current scenario of antibiotic resistance. The relationship between the spread of resistance and the contribution of different genetic elements and events is revisited, exploring examples of the processes by which successful mobile resistance genes spread across different niches. The importance of classic and next generation molecular approaches, as well as action plans and policies which might aid in the fight against antibiotic resistance, are also reviewed. Copyright © 2015 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  12. Temperament and Young Children with Visual Impairments: Perceptions of Anglo and Latino Parents

    Science.gov (United States)

    Dote-Kwan, Jamie; Chen, Deborah

    2010-01-01

    This study examined the temperamental characteristics of 18 toddlers with visual impairments as reported by their Anglo and Latino (Mexican American) parents. Differences in the parents' ratings of the children's temperament were related to the children's level of visual functioning and development. No differences were related to the children's…

  13. Understanding balance differences in individuals with multiple sclerosis with mild disability: An investigation of differences in sensory feedback on postural and dynamic balance control

    Science.gov (United States)

    Denomme, Luke T.

    Multiple sclerosis (MS) is an autoimmune disease that affects the central nervous system (CNS) and causes a broad range of neurological symptoms. One of the most common symptoms experienced by individuals with MS is poor balance control during standing and walking. The main mechanism underlying impaired balance control in MS appears to result from slowed somatosensory conduction and impaired central integration. The current thesis assessed postural and dynamic control of balance of 'individuals with MS with mild disability' (IwMS). IwMS were compared to 'healthy age-matched individuals' (HAMI) and community-dwelling 'older adults' (OA). The purpose of this thesis was to quantify differences in postural and dynamic control of balance in IwMS to the two populations who display balance control differences across the lifespan and represent two extreme ends of the balance control continuum due to natural aging. IwMS (n = 12, x¯age: 44 +/- 9.4 years), HAMI (n = 12, x¯age: 45 +/- 9.9 years) and community-dwelling OA (n = 12, x¯ age: 68.1 +/- 4.5 years) postural and dynamic balance control were evaluated during a Romberg task as well as a dynamic steering task. The Romberg task required participants to stand with their feet together and hands by their sides for 45 seconds with either their eyes open or closed. The dynamic steering task required participants to walk and change direction along the M-L plane towards a visual goal. Results from these two tasks reveal that IwMS display differences in postural control when compared to HAMI when vision was removed as well as differences in dynamic stability margin during steering situations. During the postural control task IwMS displayed faster A-P and M-L COP velocities when vision was removed and their COP position was closer to their self-selected maximum stability limits compared to HAMI. Assessment of dynamic stability during the steering task revealed that IwMS displayed reduced walking speed and cadence during the

  14. Dynamic connectivity states estimated from resting fMRI Identify differences among Schizophrenia, bipolar disorder, and healthy control subjects.

    Science.gov (United States)

    Rashid, Barnaly; Damaraju, Eswar; Pearlson, Godfrey D; Calhoun, Vince D

    2014-01-01

    Schizophrenia (SZ) and bipolar disorder (BP) share significant overlap in clinical symptoms, brain characteristics, and risk genes, and both are associated with dysconnectivity among large-scale brain networks. Resting state functional magnetic resonance imaging (rsfMRI) data facilitates studying macroscopic connectivity among distant brain regions. Standard approaches to identifying such connectivity include seed-based correlation and data-driven clustering methods such as independent component analysis (ICA) but typically focus on average connectivity. In this study, we utilize ICA on rsfMRI data to obtain intrinsic connectivity networks (ICNs) in cohorts of healthy controls (HCs) and age matched SZ and BP patients. Subsequently, we investigated difference in functional network connectivity, defined as pairwise correlations among the timecourses of ICNs, between HCs and patients. We quantified differences in both static (average) and dynamic (windowed) connectivity during the entire scan duration. Disease-specific differences were identified in connectivity within different dynamic states. Notably, results suggest that patients make fewer transitions to some states (states 1, 2, and 4) compared to HCs, with most such differences confined to a single state. SZ patients showed more differences from healthy subjects than did bipolars, including both hyper and hypo connectivity in one common connectivity state (dynamic state 3). Also group differences between SZ and bipolar patients were identified in patterns (states) of connectivity involving the frontal (dynamic state 1) and frontal-parietal regions (dynamic state 3). Our results provide new information about these illnesses and strongly suggest that state-based analyses are critical to avoid averaging together important factors that can help distinguish these clinical groups.

  15. Comparison of different methods for the determination of dynamic characteristics of low velocity anemometers

    DEFF Research Database (Denmark)

    Melikov, Arsen Krikor; Popiolek, Z.

    2004-01-01

    Three methods for determining the dynamic characteristics of low velocity thermal anemometers were compared. They were: step-up velocity change and step-down velocity change methods and a method based on sinusoidal type velocity fluctuations. Two low velocity thermal anemometers with omnidirectio......Three methods for determining the dynamic characteristics of low velocity thermal anemometers were compared. They were: step-up velocity change and step-down velocity change methods and a method based on sinusoidal type velocity fluctuations. Two low velocity thermal anemometers...... with omnidirectional velocity sensors were tested. The results identify differences in frequency response of low velocity anemometers determined by the three methods. The time constant and the response time determined by the step-up velocity change method and the step-down velocity change method may be substantially...... different and insufficient for describing the frequency response of all low velocity thermal anemometers. Therefore the upper frequency, determined in tests with sinusoidal velocity fluctuations, is recommended to be used in indoor climate standards as a single parameter describing the dynamic...

  16. Gender differences in head-neck segment dynamic stabilization during head acceleration.

    Science.gov (United States)

    Tierney, Ryan T; Sitler, Michael R; Swanik, C Buz; Swanik, Kathleen A; Higgins, Michael; Torg, Joseph

    2005-02-01

    Recent epidemiological research has revealed that gender differences exist in concussion incidence but no study has investigated why females may be at greater risk of concussion. Our purpose was to determine whether gender differences existed in head-neck segment kinematic and neuromuscular control variables responses to an external force application with and without neck muscle preactivation. Forty (20 females and 20 males) physically active volunteers participated in the study. The independent variables were gender, force application (known vs unknown), and force direction (forced flexion vs forced extension). The dependent variables were kinematic and EMG variables, head-neck segment stiffness, and head-neck segment flexor and extensor isometric strength. Statistical analyses consisted of multiple multivariate and univariate analyses of variance, follow-up univariate analyses of variance, and t-tests (P Gender differences existed in head-neck segment dynamic stabilization during head angular acceleration. Females exhibited significantly greater head-neck segment peak angular acceleration (50%) and displacement (39%) than males despite initiating muscle activity significantly earlier (SCM only) and using a greater percentage of their maximum head-neck segment muscle activity (79% peak activity and 117% muscle activity area). The head-neck segment angular acceleration differences may be because females exhibited significantly less isometric strength (49%), neck girth (30%), and head mass (43%), resulting in lower levels of head-neck segment stiffness (29%). For our subject demographic, the results revealed gender differences in head-neck segment dynamic stabilization during head acceleration in response to an external force application. Females exhibited significantly greater head-neck segment peak angular acceleration and displacement than males despite initiating muscle activity earlier (SCM only) and using a greater percentage of their maximum head-neck segment

  17. Individual Differences in Search and Monitoring for Color Targets in Dynamic Visual Displays.

    Science.gov (United States)

    Muhl-Richardson, Alex; Godwin, Hayward J; Garner, Matthew; Hadwin, Julie A; Liversedge, Simon P; Donnelly, Nick

    2018-02-01

    Many real-world tasks now involve monitoring visual representations of data that change dynamically over time. Monitoring dynamically changing displays for the onset of targets can be done in two ways: detecting targets directly, post-onset, or predicting their onset from the prior state of distractors. In the present study, participants' eye movements were measured as they monitored arrays of 108 colored squares whose colors changed systematically over time. Across three experiments, the data show that participants detected the onset of targets both directly and predictively. Experiments 1 and 2 showed that predictive detection was only possible when supported by sequential color changes that followed a scale ordered in color space. Experiment 3 included measures of individual differences in working memory capacity (WMC) and anxious affect and a manipulation of target prevalence in the search task. It found that predictive monitoring for targets, and decisions about target onsets, were influenced by interactions between individual differences in verbal and spatial WMC and intolerance of uncertainty, a characteristic that reflects worry about uncertain future events. The results have implications for the selection of individuals tasked with monitoring dynamic visual displays for target onsets. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  18. Dynamic contrast-enhanced MRI of the prostate. Comparison of two different post-processing algorithms

    International Nuclear Information System (INIS)

    Beyersdorff, Dirk; Franiel, T.; Luedemann, L.; Dietz, E.; Galler, D.; Marchot, P.

    2011-01-01

    Purpose: To evaluate the usefulness of a commercially available post-processing software tool for detecting prostate cancer on dynamic contrast-enhanced magnetic resonance imaging (MRI) and to compare the results to those obtained with a custom-made post-processing algorithm already tested under clinical conditions. Materials and Methods: Forty-eight patients with proven prostate cancer were examined by standard MRI supplemented by dynamic contrast-enhanced dual susceptibility contrast (DCE-DSC) MRI prior to prostatectomy. A custom-made post-processing algorithm was used to analyze the MRI data sets and the results were compared to those obtained using a post-processing algorithm from Invivo Corporation (Dyna CAD for Prostate) applied to dynamic T 1-weighted images. Histology was used as the gold standard. Results: The sensitivity for prostate cancer detection was 78 % for the custom-made algorithm and 60 % for the commercial algorithm and the specificity was 79 % and 82 %, respectively. The accuracy was 79 % for our algorithm and 77.5 % for the commercial software tool. The chi-square test (McNemar-Bowker test) yielded no significant differences between the two tools (p = 0.06). Conclusion: The two investigated post-processing algorithms did not differ in terms of prostate cancer detection. The commercially available software tool allows reliable and fast analysis of dynamic contrast-enhanced MRI for the detection of prostate cancer. (orig.)

  19. Parenting Practices at 24 to 47 Months and IQ at Age 8: Effect-Measure Modification by Infant Temperament

    Science.gov (United States)

    Chong, Shiau Yun; Chittleborough, Catherine R.; Gregory, Tess; Mittinty, Murthy N.; Lynch, John W.; Smithers, Lisa G.

    2016-01-01

    Cognitive development might be influenced by parenting practices and child temperament. We examined whether the associations between parental warmth, control and intelligence quotient (IQ) may be heightened among children in difficult temperament. Participants were from the Avon Longitudinal Study of Parents and Children (n = 7,044). Temperament at 6 months was measured using the Revised Infant Temperament Questionnaire and classified into ‘easy’ and ‘difficult’. Parental warmth and control was measured at 24 to 47 months and both were classified into 2 groups using latent class analyses. IQ was measured at 8 years using the Wechsler Intelligence Scale for Children and dichotomized (IQ score [β = -0.52 (95% CI 1.26, 0.21)], and higher parental control was associated with lower IQ score [β = -2.21 (-2.95, -1.48)]. Stratification by temperament showed no increased risk of having low IQ in temperamentally difficult children [risk ratio (RR) = 0.97 95% CI 0.65, 1.45)] but an increased risk among temperamentally easy children (RR = 1.12 95% CI 0.95, 1.32) when parental warmth was low. There was also no increased risk of having low IQ in temperamentally difficult children (RR = 1.02 95% CI 0.69, 1.53) but there was an increased risk among temperamentally easy children (RR = 1.30 95% CI 1.11, 1.53) when parental control was high. For both parental warmth and control, there was some evidence of negative effect-measure modification by temperament on the risk-difference scale and the risk-ratio scale. It may be more appropriate to provide parenting interventions as a universal program rather than targeting children with difficult temperament. PMID:27027637

  20. Mussel dynamics model: A hydroinformatics tool for analyzing the effects of different stressors on the dynamics of freshwater mussel communities

    Science.gov (United States)

    Morales, Y.; Weber, L.J.; Mynett, A.E.; Newton, T.J.

    2006-01-01

    A model for simulating freshwater mussel population dynamics is presented. The model is a hydroinformatics tool that integrates principles from ecology, river hydraulics, fluid mechanics and sediment transport, and applies the individual-based modelling approach for simulating population dynamics. The general model layout, data requirements, and steps of the simulation process are discussed. As an illustration, simulation results from an application in a 10 km reach of the Upper Mississippi River are presented. The model was used to investigate the spatial distribution of mussels and the effects of food competition in native unionid mussel communities, and communities infested by Dreissena polymorpha, the zebra mussel. Simulation results were found to be realistic and coincided with data obtained from the literature. These results indicate that the model can be a useful tool for assessing the potential effects of different stressors on long-term population dynamics, and consequently, may improve the current understanding of cause and effect relationships in freshwater mussel communities. ?? 2006 Elsevier B.V. All rights reserved.

  1. Different performances in static and dynamic imagery and real locomotion. An exploratory trial.

    Directory of Open Access Journals (Sweden)

    Augusto eFusco

    2014-10-01

    Full Text Available Motor imagery is a mental representation of an action without its physical execution. Recently, the simultaneous movement of the body has been added to the mental simulation. This refers to dynamic motor imagery (dMI. This study was aimed at analyzing the temporal features for static and dMI in different locomotor conditions (natural walking, NW, light running, LR, lateral walking, LW, backward walking, BW, and whether these performances were more related to all the given conditions or present only in walking. We have been also evaluated the steps performed in the dMI in comparison with the ones performed by real locomotion. Twenty healthy participants (29.3 ± 5.1 y. old were asked to move towards a visualized target located at 10mt. In dMI, no significant temporal differences respect the actual locomotion were found for all the given tasks (NW: p=0.058, LR: p=0.636, BW: p=0.096; LW: p=0,487. Significant temporal differences between static imagery and actual movements were found for LR (p<0.001 and LW (p<0.001, due to an underestimation of time needed to achieve the target in imagined locomotion. Significant differences in terms of number of steps among tasks were found for LW (p<0.001 and BW (p=0.036, whereas neither in NW (p=0.124 nor LR (p=0.391 between dMI and real locomotion.Our results confirmed that motor imagery is a task-dependent process, with walking being temporally closer than other locomotor conditions. Moreover, the time records of dynamic motor imagery are nearer to the ones of actual locomotion respect than the ones of static motor imagery. Keywords: Walking, dynamic motor imagery, human locomotion, chronometry.

  2. Extracting protein dynamics information from overlapped NMR signals using relaxation dispersion difference NMR spectroscopy.

    Science.gov (United States)

    Konuma, Tsuyoshi; Harada, Erisa; Sugase, Kenji

    2015-12-01

    Protein dynamics plays important roles in many biological events, such as ligand binding and enzyme reactions. NMR is mostly used for investigating such protein dynamics in a site-specific manner. Recently, NMR has been actively applied to large proteins and intrinsically disordered proteins, which are attractive research targets. However, signal overlap, which is often observed for such proteins, hampers accurate analysis of NMR data. In this study, we have developed a new methodology called relaxation dispersion difference that can extract conformational exchange parameters from overlapped NMR signals measured using relaxation dispersion spectroscopy. In relaxation dispersion measurements, the signal intensities of fluctuating residues vary according to the Carr-Purcell-Meiboon-Gill pulsing interval, whereas those of non-fluctuating residues are constant. Therefore, subtraction of each relaxation dispersion spectrum from that with the highest signal intensities, measured at the shortest pulsing interval, leaves only the signals of the fluctuating residues. This is the principle of the relaxation dispersion difference method. This new method enabled us to extract exchange parameters from overlapped signals of heme oxygenase-1, which is a relatively large protein. The results indicate that the structural flexibility of a kink in the heme-binding site is important for efficient heme binding. Relaxation dispersion difference requires neither selectively labeled samples nor modification of pulse programs; thus it will have wide applications in protein dynamics analysis.

  3. Extracting protein dynamics information from overlapped NMR signals using relaxation dispersion difference NMR spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Konuma, Tsuyoshi [Icahn School of Medicine at Mount Sinai, Department of Structural and Chemical Biology (United States); Harada, Erisa [Suntory Foundation for Life Sciences, Bioorganic Research Institute (Japan); Sugase, Kenji, E-mail: sugase@sunbor.or.jp, E-mail: sugase@moleng.kyoto-u.ac.jp [Kyoto University, Department of Molecular Engineering, Graduate School of Engineering (Japan)

    2015-12-15

    Protein dynamics plays important roles in many biological events, such as ligand binding and enzyme reactions. NMR is mostly used for investigating such protein dynamics in a site-specific manner. Recently, NMR has been actively applied to large proteins and intrinsically disordered proteins, which are attractive research targets. However, signal overlap, which is often observed for such proteins, hampers accurate analysis of NMR data. In this study, we have developed a new methodology called relaxation dispersion difference that can extract conformational exchange parameters from overlapped NMR signals measured using relaxation dispersion spectroscopy. In relaxation dispersion measurements, the signal intensities of fluctuating residues vary according to the Carr-Purcell-Meiboon-Gill pulsing interval, whereas those of non-fluctuating residues are constant. Therefore, subtraction of each relaxation dispersion spectrum from that with the highest signal intensities, measured at the shortest pulsing interval, leaves only the signals of the fluctuating residues. This is the principle of the relaxation dispersion difference method. This new method enabled us to extract exchange parameters from overlapped signals of heme oxygenase-1, which is a relatively large protein. The results indicate that the structural flexibility of a kink in the heme-binding site is important for efficient heme binding. Relaxation dispersion difference requires neither selectively labeled samples nor modification of pulse programs; thus it will have wide applications in protein dynamics analysis.

  4. Individual Differences in Cognitive and Noncognitive Abilities and Team Performance in Dynamic Task Environments

    National Research Council Canada - National Science Library

    Doane, Stephanie

    2004-01-01

    The specific goal of this research was to examine the role of individual differences in cognitive and non-cognitive abilities on individual and team performance in a real-time dynamic team-task environment...

  5. Examining inter-family differences in intra-family (parent-adolescent) dynamics using grid-sequence analysis.

    Science.gov (United States)

    Brinberg, Miriam; Fosco, Gregory M; Ram, Nilam

    2017-12-01

    Family systems theorists have forwarded a set of theoretical principles meant to guide family scientists and practitioners in their conceptualization of patterns of family interaction-intra-family dynamics-that, over time, give rise to family and individual dysfunction and/or adaptation. In this article, we present an analytic approach that merges state space grid methods adapted from the dynamic systems literature with sequence analysis methods adapted from molecular biology into a "grid-sequence" method for studying inter-family differences in intra-family dynamics. Using dyadic data from 86 parent-adolescent dyads who provided up to 21 daily reports about connectedness, we illustrate how grid-sequence analysis can be used to identify a typology of intrafamily dynamics and to inform theory about how specific types of intrafamily dynamics contribute to adolescent behavior problems and family members' mental health. Methodologically, grid-sequence analysis extends the toolbox of techniques for analysis of family experience sampling and daily diary data. Substantively, we identify patterns of family level microdynamics that may serve as new markers of risk/protective factors and potential points for intervention in families. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  6. Influence of impulsivity-reflexivity when testing dynamic spatial ability: sex and g differences.

    Science.gov (United States)

    Quiroga, M Angeles; Hernández, José Manuel; Rubio, Victor; Shih, Pei Chun; Santacreu, José

    2007-11-01

    This work analyzes the possibility that the differences in the performance of men and women in dynamic spatial tasks such as the Spatial Orientation Dynamic Test-Revised (SODT-R; Santacreu & Rubio, 1998), obtained in previous works, are due to cognitive style (Reflexivity-Impulsivity) or to the speed-accuracy tradeoff (SATO) that the participants implement. If these differences are due to cognitive style, they would be independent of intelligence, whereas if they are due to SATO, they may be associated with intelligence. In this work, 1652 participants, 984 men and 668 women, ages between 18 and 55 years, were assessed. In addition to the SODT-R, the "Test de Razonamiento Analitico, Secuencial e Inductivo" (TRASI [Analytical, Sequential, and Inductive Reasoning Test]; Rubio & Santacreu, 2003) was administered as a measure of general intelligence. Impulsivity scores (Zi) of Salkind and Wright (1977) were used to analyze reflexivity-impulsivity and SATO. The results obtained indicate that (a) four performance groups can be identified: Fast-accurate, Slow-inaccurate, Impulsive, and Reflexive. The first two groups solve the task as a function of a competence variable and the last two as a function of a personality variable; (b) performance differences should be attributed to SATO; (c) SATO differs depending on sex and intelligence level.

  7. Differing Dynamics of Intrapersonal and Interpersonal Coordination: Two-finger and Four-Finger Tapping Experiments.

    Directory of Open Access Journals (Sweden)

    Kentaro Kodama

    Full Text Available Finger-tapping experiments were conducted to examine whether the dynamics of intrapersonal and interpersonal coordination systems can be described equally by the Haken-Kelso-Bunz model, which describes inter-limb coordination dynamics. This article reports the results of finger-tapping experiments conducted in both systems. Two within-subject factors were investigated: the phase mode and the number of fingers. In the intrapersonal experiment (Experiment 1, the participants were asked to tap, paced by a gradually hastening auditory metronome, looking at their fingers moving, using the index finger in the two finger condition, or the index and middle finger in the four-finger condition. In the interpersonal experiment (Experiment 2, pairs of participants performed the task while each participant used the outside hand, tapping with the index finger in the two finger condition, or the index and middle finger in the four-finger condition. Some results did not agree with the HKB model predictions. First, from Experiment 1, no significant difference was observed in the movement stability between the in-phase and anti-phase modes in the two finger condition. Second, from Experiment 2, no significant difference was found in the movement stability between the in-phase and anti-phase mode in the four-finger condition. From these findings, different coordination dynamics were inferred between intrapersonal and interpersonal coordination systems against prediction from the previous studies. Results were discussed according to differences between intrapersonal and interpersonal coordination systems in the availability of perceptual information and the complexity in the interaction between limbs derived from a nested structure.

  8. Arid landscape dynamics along a precipitation gradient: addressing vegetation - landscape structure - resource interactions at different time scales

    NARCIS (Netherlands)

    Buis, E.

    2008-01-01

    This research is entitled ‘Arid landscape dynamics along a precipitation gradient: addressing
    vegetation – landscape structure – resource interactions at different time scales’ with as subtitle
    ‘A case study for the Northern Negev Desert of Israel’. Landscape dynamics describes the

  9. Differences in dynamic balance scores in one sport versus multiple sport high school athletes.

    Science.gov (United States)

    Gorman, Paul P; Butler, Robert J; Rauh, Mitchell J; Kiesel, Kyle; Plisky, Phillip J

    2012-04-01

    Researchers have previously reported on the importance of dynamic balance in assessing an individual's risk for injury during sport. However, to date there is no research on whether multiple sport participation affects dynamic balance ability. Therefore, the purpose of this study was to determine if there was a difference in dynamic balance scores in high school athletes that competed in one sport only as compared athletes who competed in multiple sports, as tested by the Lower Quarter Y Balance Test (YBT-LQ). Ninety-two high school athletes who participated in one sport were matched, by age, gender and sport played, to athletes who participated in the same sport as well as additional sports. All individuals were assessed using the YBT-LQ to examine differences in composite reach score and reach direction asymmetry between single sport and multiple sport athletes. The greatest reach distance of three trials in each reach direction for right and left lower-extremities was normalized by limb length and used for analysis. A two-way ANOVA (gender x number of sports played) was used to statistically analyze the variables in the study. No significant interactions or main effects related to number of sports played were observed for any YBT-LQ score (p>0.05). Male athletes exhibited significantly greater normalized reach values for the posteromedial, posterolateral, and composite reach while also exhibiting a larger anterior reach difference when compared to the females. Athletes who participated in multiple sports had similar performances on the YBT-LQ when compared to athletes who participated in a single sport. The findings of this study suggest that the number of sports played by a high school athlete does not need to be controlled for when evaluating dynamic balance with the YBT-LQ.

  10. EXPERIMENTAL RESEARCH OF DYNAMIC QUALITIES OF FREIGHT CARS WITH BOGIES OF DIFFERENT DESIGNS

    Directory of Open Access Journals (Sweden)

    S. V. Myamlin

    2014-04-01

    Full Text Available Purpose. With the advent of new designs of freright cars the task of designing the more modern bogies, assessment of their dynamic properties depending on the type and structure of pecularities, accounting the axle loadings, providing the dynamic and running characteristics, meeting the conditions of impact on the track, stability, and frame forces intensity etc. becomes especially important. In order to launch the new production into manufacture and to assess the dynamic properties using different designs of bogies the running testes were conducted. They allowed one to compare the dynamic performance of the new bogie with the existing models. Methodology. The study was conducted using the method of numerical integration and mathematical modeling of dynamic loading of freight cars using the software package «Dynamics of Rail Vehicles» («DYNRAIL». Findings. The results of studies of dynamic characteristics of open cars with new and worn wheels of bogie models 18-9771, 18-9770 and 18-578 in graphical and tabular form are presented. All figures are within the normative values and do not exceed the maximum admissible ones. Originality. When designing the bogie for loading 23.5 t/axle almost all available technical solutions to improve the characteristics of the freight car bogies (elastic bearers, cassette bearing in axle boxes, axle boxe adapter of original design, bilinear central spring suspension, etc. were used. Practical value. As a result of the engineering works on projecting and manufacturing of the improved designs of freight car bogies a new design was received. It is highly competitive with the dynamic qualities of the best ones. Made choice of rational values of elastic-dissipative parameters of the bogie allows one to create standard series of running gears for freight cars for promising operating conditions.The results are of practical importance. They have found reflection in the number of author’spublications in special and

  11. Onset Dynamics of Action Potentials in Rat Neocortical Neurons and Identified Snail Neurons: Quantification of the Difference

    OpenAIRE

    Volgushev, Maxim; Malyshev, Aleksey; Balaban, Pavel; Chistiakova, Marina; Volgushev, Stanislav; Wolf, Fred

    2008-01-01

    The generation of action potentials (APs) is a key process in the operation of nerve cells and the communication between neurons. Action potentials in mammalian central neurons are characterized by an exceptionally fast onset dynamics, which differs from the typically slow and gradual onset dynamics seen in identified snail neurons. Here we describe a novel method of analysis which provides a quantitative measure of the onset dynamics of action potentials. This method captures the...

  12. DIFFERENT DYNAMICS FOR SOME COUNTRIES OF CEE

    Directory of Open Access Journals (Sweden)

    Cristian SPIRIDON

    2015-04-01

    Full Text Available The study addresses the economic development of four European countries - Romania, Hungary, Czech Republic, and Poland beginning with 1990. It will be employed a descriptive analysis of their trade and growth dynamics. Emphasis will be placed on the determinants of economic growth of this group of countries in general and foreign trade in particular. The results indicate a heterogeneous dynamics of economic performances explained by specific characteristics and less by exogenous aspects related to trade partners and commercial structure, regional integration or foreign policy influenced by geographic proximity. In what concerns Romania, it appears to have been driven by a weaker engine of economic growth in the last two centuries.

  13. Paradoxical differences in N-dynamics between Luxembourg soils: litter quality or parent material?

    NARCIS (Netherlands)

    Kooijman, A.M.; Smit, A.

    2009-01-01

    To explore whether litter quality could alter differences in N-dynamics between soil types, we compared spruce and beech growing on soils with parent material sandstone and limestone, and beech and hornbeam on acid marl and limestone. We measured pH, organic matter content, C:N ratio, soil

  14. Paradoxical differences in N-dynamics between Luxembourg soils: Litter quality or parent material?

    NARCIS (Netherlands)

    Kooijman, A.M.; Smit, A.

    2009-01-01

    To explore whether litter quality could alter differences in N-dynamics between soil types, we compared spruce and beech growing on soils with parent material sandstone and limestone, and beech and hornbeam on acid marl and limestone. We measured pH, organic matter content, C:N ratio, soil

  15. Stereo Vision-Based High Dynamic Range Imaging Using Differently-Exposed Image Pair

    Directory of Open Access Journals (Sweden)

    Won-Jae Park

    2017-06-01

    Full Text Available In this paper, a high dynamic range (HDR imaging method based on the stereo vision system is presented. The proposed method uses differently exposed low dynamic range (LDR images captured from a stereo camera. The stereo LDR images are first converted to initial stereo HDR images using the inverse camera response function estimated from the LDR images. However, due to the limited dynamic range of the stereo LDR camera, the radiance values in under/over-exposed regions of the initial main-view (MV HDR image can be lost. To restore these radiance values, the proposed stereo matching and hole-filling algorithms are applied to the stereo HDR images. Specifically, the auxiliary-view (AV HDR image is warped by using the estimated disparity between initial the stereo HDR images and then effective hole-filling is applied to the warped AV HDR image. To reconstruct the final MV HDR, the warped and hole-filled AV HDR image is fused with the initial MV HDR image using the weight map. The experimental results demonstrate objectively and subjectively that the proposed stereo HDR imaging method provides better performance compared to the conventional method.

  16. Triggered dynamics in a model of different fault creep regimes.

    Science.gov (United States)

    Kostić, Srđan; Franović, Igor; Perc, Matjaž; Vasović, Nebojša; Todorović, Kristina

    2014-06-23

    The study is focused on the effect of transient external force induced by a passing seismic wave on fault motion in different creep regimes. Displacement along the fault is represented by the movement of a spring-block model, whereby the uniform and oscillatory motion correspond to the fault dynamics in post-seismic and inter-seismic creep regime, respectively. The effect of the external force is introduced as a change of block acceleration in the form of a sine wave scaled by an exponential pulse. Model dynamics is examined for variable parameters of the induced acceleration changes in reference to periodic oscillations of the unperturbed system above the supercritical Hopf bifurcation curve. The analysis indicates the occurrence of weak irregular oscillations if external force acts in the post-seismic creep regime. When fault motion is exposed to external force in the inter-seismic creep regime, one finds the transition to quasiperiodic- or chaos-like motion, which we attribute to the precursory creep regime and seismic motion, respectively. If the triggered acceleration changes are of longer duration, a reverse transition from inter-seismic to post-seismic creep regime is detected on a larger time scale.

  17. A dynamic processes study of PM retention by trees under different wind conditions.

    Science.gov (United States)

    Xie, Changkun; Kan, Liyan; Guo, Jiankang; Jin, Sijia; Li, Zhigang; Chen, Dan; Li, Xin; Che, Shengquan

    2018-02-01

    Particulate matter (PM) is one of the most serious environmental problems, exacerbating respiratory and vascular illnesses. Plants have the ability to reduce non-point source PM pollution through retention on leaves and branches. Studies of the dynamic processes of PM retention by plants and the mechanisms influencing this process will help to improve the efficiency of urban greening for PM reduction. We examined dynamic processes of PM retention and the major factors influencing PM retention by six trees with different branch structure characteristics in wind tunnel experiments at three different wind speeds. The results showed that the changes of PM numbers retained by plant leaves over time were complex dynamic processes for which maximum values could exceed minimum values by over 10 times. The average value of PM measured in multiple periods and situations can be considered a reliable indicator of the ability of the plant to retain PM. The dynamic processes were similar for PM 10 and PM 2.5 . They could be clustered into three groups simulated by continually-rising, inverse U-shaped, and U-shaped polynomial functions, respectively. The processes were the synthetic effect of characteristics such as species, wind speed, period of exposure and their interactions. Continually-rising functions always explained PM retention in species with extremely complex branch structure. Inverse U-shaped processes explained PM retention in species with relatively simple branch structure and gentle wind. The U-shaped processes mainly explained PM retention at high wind speeds and in species with a relatively simple crown. These results indicate that using plants with complex crowns in urban greening and decreasing wind speed in plant communities increases the chance of continually-rising or inverse U-shaped relationships, which have a positive effect in reducing PM pollution. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Spatio-temporal correlations in models of collective motion ruled by different dynamical laws.

    Science.gov (United States)

    Cavagna, Andrea; Conti, Daniele; Giardina, Irene; Grigera, Tomas S; Melillo, Stefania; Viale, Massimiliano

    2016-11-15

    Information transfer is an essential factor in determining the robustness of biological systems with distributed control. The most direct way to study the mechanisms ruling information transfer is to experimentally observe the propagation across the system of a signal triggered by some perturbation. However, this method may be inefficient for experiments in the field, as the possibilities to perturb the system are limited and empirical observations must rely on natural events. An alternative approach is to use spatio-temporal correlations to probe the information transfer mechanism directly from the spontaneous fluctuations of the system, without the need to have an actual propagating signal on record. Here we test this method on models of collective behaviour in their deeply ordered phase by using ground truth data provided by numerical simulations in three dimensions. We compare two models characterized by very different dynamical equations and information transfer mechanisms: the classic Vicsek model, describing an overdamped noninertial dynamics and the inertial spin model, characterized by an underdamped inertial dynamics. By using dynamic finite-size scaling, we show that spatio-temporal correlations are able to distinguish unambiguously the diffusive information transfer mechanism of the Vicsek model from the linear mechanism of the inertial spin model.

  19. Peer Preference: A Way of Evaluating Social Competence and Behavioural Well-Being in Early Childhood

    Science.gov (United States)

    Öneren Sendil, Çagla; Tantekin Erden, Feyza

    2014-01-01

    This study investigated the differences in peer preference, gender and temperamental characteristics of children aged five to six in relation to their social competence (SC) and behavioural adaptation. The data were collected through the use of "Picture Sociometry Scale", "SC and Behaviour Evaluation Scale" and "Short…

  20. Predicting Social Wariness in Middle Childhood: The Moderating Roles of Childcare History, Maternal Personality and Maternal Behavior

    Science.gov (United States)

    Degnan, Kathryn Amey; Henderson, Heather A.; Fox, Nathan A.; Rubin, Kenneth H.

    2008-01-01

    Children with behavioral inhibition, a temperamental style characterized by infant distress to novelty and childhood social reticence, exhibit both continuity and discontinuity of this behavioral trait over the course of development. However, few researchers have identified factors that might be responsible for these different patterns. In the…

  1. Dynamic behaviour of nominal and PACMAN bunches for different LHC crossing schemes

    CERN Document Server

    Herr, Werner

    2005-01-01

    To avoid unwanted beam-beam interactions, the two LHC beams cross at an angle in all experimental interaction regions. The choice of the crossing plane in the different areas has fundamental consequences on the effects of the long range beam-beam interaction. An alternating crossing scheme, i.e. horizontal and vertical crossing planes in the two high luminosity experiments, is presently foreseen to partly compensate and minimize first order effects on PACMAN bunches. Recent studies with a simplified model of the machine suggested that an alternating crossing scheme may be less favourable due to a reduced dynamic aperture. In this report I investigate this assertion with a detailed tracking study. The head on and long range beam-beam effects are taken into account as well as machine imperfections. The effects on the dynamic aperture of nominal and PACMAN bunches are evaluated.

  2. Helium Adsorption on Carbon Nanotube Bundles with Different Diameters:. Molecular Dynamics Simulation

    Science.gov (United States)

    Majidi, R.; Karami, A. R.

    2013-05-01

    We have used molecular dynamics simulation to study helium adsorption capacity of carbon nanotube bundles with different diameters. Homogeneous carbon nanotube bundles of (8,8), (9,9), (10,10), (11,11), and (12,12) single walled carbon nanotubes have been considered. The results indicate that the exohedral adsorption coverage does not depend on the diameter of carbon nanotubes, while the endohedral adsorption coverage is increased by increasing the diameter.

  3. Dynamic Behaviour of Different Types of Cable-Stayed Bridges Due to Earthquake Loads

    Directory of Open Access Journals (Sweden)

    Alireza Mirza Goltabar Roshan

    2016-12-01

    Full Text Available Construction of large-scale structures has been considered as one of the human's main achievements.  With their suitable view and high economical aspects, High-strength steel cables have been developed for analysis and erection of cable-stayed bridges in light of high speed development in computer technology. This type of bridges, while providing different behavior due to cable flexibility, has been recognized as one of the most practical choices for mid to large span bridges. This paper studies the non-linear dynamic behavior of cable bridges and the effect of some parameters (such as cable arrangement and shape of pylon on them. For this purpose, CSI Bridge software with the direct integration method of dynamic analysis has been used and the behavior of structure under different earthquake components has been analyzed for various conditions of cable arrangements and pylon shapes. Results indicate that the most suitable behavior would be for cable bridges with H-shape pylons arranged in series and also with A-shape pylons in radial arrangement.

  4. Temperamental precursors of infant attachment with mothers and fathers.

    Science.gov (United States)

    Planalp, Elizabeth M; Braungart-Rieker, Julia M

    2013-12-01

    The degree to which parent sensitivity and infant temperament distinguish attachment classification was examined. Multilevel modeling was used to assess the effect of parent sensitivity and infant temperament on infant-mother and infant-father attachment. Data were collected from mothers, fathers, and their infants (N = 135) when the infant was 3-, 5-, 7-, 12-, and 14-months old. Temperament was measured using the Infant Behavior Questionnaire-Revised (Gartstein & Rothbart, 2003); parent sensitivity was coded during the Still Face Paradigm (Tronick, Als, Adamson, Wise, & Brazelton, 1978); attachment was coded using the Strange Situation (Ainsworth, Blehar, Waters, & Wall, 1978). Results indicate that mothers and fathers were less sensitive with insecure-avoidant infants. Whereas only one difference was found for infant-mother attachment groups and temperament, five significant differences emerged for infant-father attachment groups, with the majority involving insecure-ambivalent attachment. Infants classified as ambivalent with fathers were higher in perceptual sensitivity and cuddliness and these infants also showed a greater increase in low-intensity pleasure over time compared with other infants. Results indicate the importance of both parent sensitivity and infant temperament, though operating in somewhat different ways, in the development of the infant-mother and infant-father attachment relationship. Copyright © 2013 Elsevier Inc. All rights reserved.

  5. Temperamental precursors of infant attachment with mothers and fathers☆

    Science.gov (United States)

    Planalp, Elizabeth M.; Braungart-Rieker, Julia M.

    2013-01-01

    The degree to which parent sensitivity and infant temperament distinguish attachment classification was examined. Multilevel modeling was used to assess the effect of parent sensitivity and infant temperament on infant–mother and infant–father attachment. Data were collected from mothers, fathers, and their infants (N = 135) when the infant was 3-, 5-, 7-, 12-, and 14-months old. Temperament was measured using the Infant Behavior Questionnaire-Revised (Gartstein & Rothbart, 2003); parent sensitivity was coded during the Still Face Paradigm (Tronick, Als, Adamson, Wise, & Brazelton, 1978); attachment was coded using the Strange Situation (Ainsworth, Blehar, Waters, & Wall, 1978). Results indicate that mothers and fathers were less sensitive with insecure-avoidant infants. Whereas only one difference was found for infant–mother attachment groups and temperament, five significant differences emerged for infant–father attachment groups, with the majority involving insecure-ambivalent attachment. Infants classified as ambivalent with fathers were higher in perceptual sensitivity and cuddliness and these infants also showed a greater increase in low-intensity pleasure over time compared with other infants. Results indicate the importance of both parent sensitivity and infant temperament, though operating in somewhat different ways, in the development of the infant–mother and infant–father attachment relationship. PMID:24103401

  6. Nonlinear dynamics of solitary and optically injected two-element laser arrays with four different waveguide structures: a numerical study.

    Science.gov (United States)

    Li, Nianqiang; Susanto, H; Cemlyn, B R; Henning, I D; Adams, M J

    2018-02-19

    We study the nonlinear dynamics of solitary and optically injected two-element laser arrays with a range of waveguide structures. The analysis is performed with a detailed direct numerical simulation, where high-resolution dynamic maps are generated to identify regions of dynamic instability in the parameter space of interest. Our combined one- and two-parameter bifurcation analysis uncovers globally diverse dynamical regimes (steady-state, oscillation, and chaos) in the solitary laser arrays, which are greatly influenced by static design waveguiding structures, the amplitude-phase coupling factor of the electric field, i.e. the linewidth-enhancement factor, as well as the control parameter, e.g. the pump rate. When external optical injection is introduced to one element of the arrays, we show that the whole system can be either injection-locked simultaneously or display rich, different dynamics outside the locking region. The effect of optical injection is to significantly modify the nature and the regions of nonlinear dynamics from those found in the solitary case. We also show similarities and differences (asymmetry) between the oscillation amplitude of the two elements of the array in specific well-defined regions, which hold for all the waveguiding structures considered. Our findings pave the way to a better understanding of dynamic instability in large arrays of lasers.

  7. Investigation of the difference between spin Hall magnetoresistance rectification and spin pumping from the viewpoint of magnetization dynamics

    Science.gov (United States)

    Zhang, Qihan; Fan, Xiaolong; Zhou, Hengan; Kong, Wenwen; Zhou, Shiming; Gui, Y. S.; Hu, C.-M.; Xue, Desheng

    2018-02-01

    Spin pumping (SP) and spin rectification due to spin Hall magnetoresistance (SMR) can result in a dc resonant voltage signal, when magnetization in ferromagnetic insulator/nonmagnetic structures experiences ferromagnetic resonance. Since the two effects are often interrelated, quantitative identification of them is important for studying the dynamic nonlocal spin transport through an interface. In this letter, the key difference between SP and SMR rectification was investigated from the viewpoint of spin dynamics. The phase-dependent nature of SMR rectification, which is the fundamental characteristic distinguishing it from SP, was tested by a well-designed experiment. In this experiment, two identical yttrium iron garnet/Pt strips with a π phase difference in dynamic magnetization show the same SP signals and inverse SMR signals.

  8. Factorization of the hypergeometric-type difference equation on non-uniform lattices: dynamical algebra

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez-Nodarse, R [Departamento de Analisis Matematico, Universidad de Sevilla, Apdo. 1160, E-41080 Sevilla (Spain); Atakishiyev, N M [Instituto de Matematicas, UNAM, Apartado Postal 273-3, CP 62210 Cuernavaca, Morelos, Mexico (Germany); Costas-Santos, R S [Departamento de Matematicas, EPS, Universidad Carlos III de Madrid, Ave. Universidad 30, E-28911, Leganes, Madrid (Spain)

    2005-01-07

    We argue that one can factorize the difference equation of hypergeometric type on non-uniform lattices in the general case. It is shown that in the most cases of q-linear spectrum of the eigenvalues, this directly leads to the dynamical symmetry algebra su{sub q}(1, 1), whose generators are explicitly constructed in terms of the difference operators, obtained in the process of factorization. Thus all models with the q-linear spectrum (some of them, but not all, previously considered in a number of publications) can be treated in a unified form.

  9. Wearout Effects of Different Advertising Themes: A Dynamic Bayesian Model of the Advertising-Sales Relationship

    OpenAIRE

    Frank M. Bass; Norris Bruce; Sumit Majumdar; B. P. S. Murthi

    2007-01-01

    Models of advertising response implicitly assume that the entire advertising budget is spent on disseminating one message. In practice, managers use different themes of advertising (for example, price advertisements versus product advertisements) and within each theme they employ different versions of an advertisement. In this study, we evaluate the dynamic effects of different themes of advertising that have been employed in a campaign. We develop a model that jointly considers the effects o...

  10. Urinary catecholamine concentrations in three beef breeds at ...

    African Journals Online (AJOL)

    Handling and transport of live animals is a stressful experience for animals. The temperaments of cattle affect their behaviour and differ between breeds, i.e. studies have shown that Bos indicus types are more temperamental than Sanga and Bos taurus types. Catecholamines (CAT's) are considered as indicators of stress, ...

  11. Simulation of the biomass dynamics of Masson pine forest under different management

    Institute of Scientific and Technical Information of China (English)

    ZHANG Gui-lian; WANG Kai-yun; LIU Xin-wei; PENG Shao-lin

    2006-01-01

    TREE submodel affiliated with TREEDYN was used to simulate biomass dynamics of Masson pine (Pinus massoniana) forest under different managements (including thinning, clear cutting, combining thinning with clear cutting). The purpose was to represent biomass dynamics involved in its development, which can provide scientific arguments for management of Masson pine forest. The results showed the scenario that 10% or 20% of biomass of the previous year was thinned every five years from 15 to 40 years made total biomass of pine forest increase slowly and it took more time to reach a mature community; If clear cutting and thinning were combined, the case C (clear cutting at 20 years of forest age, thinning 50% of remaining biomass at 30 years of forest age, and thinning 50% of remaining biomass again at 40 years of forest age) was the best scenario which can accelerate speed of development of Masson pine forest and gained better economic values.

  12. Finite difference method for inner-layer equations in the resistive MagnetoHydroDynamic stability analysis

    International Nuclear Information System (INIS)

    Tokuda, Shinji; Watanabe, Tomoko.

    1996-08-01

    The matching problem in resistive MagnetoHydroDynamic stability analysis by the asymptotic matching method has been reformulated as an initial-boundary value problem for the inner-layer equations describing the plasma dynamics in the thin layer around a rational surface. The third boundary conditions at boundaries of a finite interval are imposed on the inner layer equations in the formulation instead of asymptotic conditions at infinities. The finite difference method for this problem has been applied to model equations whose solutions are known in a closed form. It has been shown that the initial value problem and the associated eigenvalue problem for the model equations can be solved by the finite difference method with numerical stability. The formulation presented here enables the asymptotic matching method to be a practical method for the resistive MHD stability analysis. (author)

  13. Comparison of precise orbit determination methods of zero-difference kinematic, dynamic and reduced-dynamic of GRACE-A satellite using SHORDE software

    Science.gov (United States)

    Li, Kai; Zhou, Xuhua; Guo, Nannan; Zhao, Gang; Xu, Kexin; Lei, Weiwei

    2017-09-01

    Zero-difference kinematic, dynamic and reduced-dynamic precise orbit determination (POD) are three methods to obtain the precise orbits of Low Earth Orbit satellites (LEOs) by using the on-board GPS observations. Comparing the differences between those methods have great significance to establish the mathematical model and is usefull for us to select a suitable method to determine the orbit of the satellite. Based on the zero-difference GPS carrier-phase measurements, Shanghai Astronomical Observatory (SHAO) has improved the early version of SHORDE and then developed it as an integrated software system, which can perform the POD of LEOs by using the above three methods. In order to introduce the function of the software, we take the Gravity Recovery And Climate Experiment (GRACE) on-board GPS observations in January 2008 as example, then we compute the corresponding orbits of GRACE by using the SHORDE software. In order to evaluate the accuracy, we compare the orbits with the precise orbits provided by Jet Propulsion Laboratory (JPL). The results show that: (1) If we use the dynamic POD method, and the force models are used to represent the non-conservative forces, the average accuracy of the GRACE orbit is 2.40cm, 3.91cm, 2.34cm and 5.17cm in radial (R), along-track (T), cross-track (N) and 3D directions respectively; If we use the accelerometer observation instead of non-conservative perturbation model, the average accuracy of the orbit is 1.82cm, 2.51cm, 3.48cm and 4.68cm in R, T, N and 3D directions respectively. The result shows that if we use accelerometer observation instead of the non-conservative perturbation model, the accuracy of orbit is better. (2) When we use the reduced-dynamic POD method to get the orbits, the average accuracy of the orbit is 0.80cm, 1.36cm, 2.38cm and 2.87cm in R, T, N and 3D directions respectively. This method is carried out by setting up the pseudo-stochastic pulses to absorb the errors of atmospheric drag and other

  14. Detection of dynamically varying interaural time differences

    DEFF Research Database (Denmark)

    Kohlrausch, Armin; Le Goff, Nicolas; Breebaart, Jeroen

    2010-01-01

    of fringes surrounding the probe is equal to the addition of the effects of the individual fringes. In this contribution, we present behavioral data for the same experimental condition, called dynamically varying ITD detection, but for a wider range of probe and fringe durations. Probe durations varied...

  15. Quantifying sleep architecture dynamics and individual differences using big data and Bayesian networks.

    Science.gov (United States)

    Yetton, Benjamin D; McDevitt, Elizabeth A; Cellini, Nicola; Shelton, Christian; Mednick, Sara C

    2018-01-01

    The pattern of sleep stages across a night (sleep architecture) is influenced by biological, behavioral, and clinical variables. However, traditional measures of sleep architecture such as stage proportions, fail to capture sleep dynamics. Here we quantify the impact of individual differences on the dynamics of sleep architecture and determine which factors or set of factors best predict the next sleep stage from current stage information. We investigated the influence of age, sex, body mass index, time of day, and sleep time on static (e.g. minutes in stage, sleep efficiency) and dynamic measures of sleep architecture (e.g. transition probabilities and stage duration distributions) using a large dataset of 3202 nights from a non-clinical population. Multi-level regressions show that sex effects duration of all Non-Rapid Eye Movement (NREM) stages, and age has a curvilinear relationship for Wake After Sleep Onset (WASO) and slow wave sleep (SWS) minutes. Bayesian network modeling reveals sleep architecture depends on time of day, total sleep time, age and sex, but not BMI. Older adults, and particularly males, have shorter bouts (more fragmentation) of Stage 2, SWS, and they transition less frequently to these stages. Additionally, we showed that the next sleep stage and its duration can be optimally predicted by the prior 2 stages and age. Our results demonstrate the potential benefit of big data and Bayesian network approaches in quantifying static and dynamic architecture of normal sleep.

  16. Temperamental differences between bipolar disorder, borderline personality disorder, and attention deficit/hyperactivity disorder: some implications for their diagnostic validity.

    Science.gov (United States)

    Eich, Dominique; Gamma, Alex; Malti, Tina; Vogt Wehrli, Marianne; Liebrenz, Michael; Seifritz, Erich; Modestin, Jiri

    2014-12-01

    The relationship between borderline personality disorder (BPD), bipolar disorder (BD), and attention deficit/hyperactivity disorder (ADHD) requires further elucidation. Seventy-four adult psychiatric in- and out-patients, each of them having received one of these diagnoses on clinical assessment, were interviewed and compared in terms of diagnostic overlap, age and sex distribution, comorbid substance, anxiety and eating disorders, and affective temperament. Diagnostic overlap within the three disorders was 54%. Comorbidity patterns and gender ratio did not differ. The disorders showed very similar levels of cyclothymia. Sample size was small and only a limited number of validators were tested. The similar extent of cyclothymic temperament suggests mood lability as a common denominator of BPD, BD, and ADHD. Copyright © 2014. Published by Elsevier B.V.

  17. The influence of four different anticoagulants on dynamic light scattering of platelets.

    Science.gov (United States)

    Raczat, T; Kraemer, L; Gall, C; Weiss, D R; Eckstein, R; Ringwald, J

    2014-08-01

    For testing of dynamic light scattering of platelets with ThromboLUX (TLX) in platelet-rich plasma (PRP) derived from venous whole blood (vWB), anticoagulation is needed. We compared TLX score in PRPs containing citrate, ethylene-diamine-tetraacetic-acid (EDTA), citrate-phosphate-dextrose-adenine (CPDA) or citrate-theophylline-adenosine-dipyridamole. Initial and late TLX scores were measured after 30-120 min or four to six hours, respectively. Compared with citrate, mean differences in initial TLX score were only significant for CPDA. Also, mean differences between initial and late TLX scores were only significant for CPDA. TLX failed to detect EDTA-induced platelet alterations. The clinical relevance of TLX needs further studies. © 2014 International Society of Blood Transfusion.

  18. Dimensions of temperament modulate cue-controlled behavior: a study on Pavlovian to instrumental transfer in horses (Equus caballus.

    Directory of Open Access Journals (Sweden)

    Léa Lansade

    Full Text Available Pavlovian to instrumental transfer (PIT is a central factor in how cues influence animal behavior. PIT refers to the capacity of a Pavlovian cue that predicts a reward to elicit or increase a response intended to obtain the same reward. In the present study, using an equine model, we assessed whether PIT occurs in hoofed domestic animals and whether its efficacy can be modulated by temperamental dimensions. To study PIT, horses were submitted to Pavlovian conditioning whereby an auditory-visual stimulus was repeatedly followed by food delivery. Then, horses were submitted to instrumental conditioning during which they learned to touch with their noses an object signaled by the experimenter in order to obtain the same reward. During the PIT test, the Pavlovian conditioned stimulus was presented to the animal in the absence of reward. At the end of the experiment, a battery of behavioral tests was performed on all animals to assess five temperamental dimensions and investigate their relationships with instrumental performance. The results indicate that PIT can be observed in horses and that its efficacy is greatly modulated by individual temperament. Indeed, individuals with a specific pattern of temperamental dimensions (i.e., higher levels of gregariousness, fearfulness, and sensory sensitivity exhibited the strongest PIT. The demonstration of the existence of PIT in domesticated animals (i.e., horses is important for the optimization of its use by humans and the improvement of training methods. Moreover, because PIT may be implicated in psychological phenomena, including addictive behaviors, the observation of relationships between specific temperamental dimensions and PIT efficacy may aid in identifying predisposing temperamental attributes.

  19. Wavelength selection for portable noninvasive blood component measurement system based on spectral difference coefficient and dynamic spectrum

    Science.gov (United States)

    Feng, Ximeng; Li, Gang; Yu, Haixia; Wang, Shaohui; Yi, Xiaoqing; Lin, Ling

    2018-03-01

    Noninvasive blood component analysis by spectroscopy has been a hotspot in biomedical engineering in recent years. Dynamic spectrum provides an excellent idea for noninvasive blood component measurement, but studies have been limited to the application of broadband light sources and high-resolution spectroscopy instruments. In order to remove redundant information, a more effective wavelength selection method has been presented in this paper. In contrast to many common wavelength selection methods, this method is based on sensing mechanism which has a clear mechanism and can effectively avoid the noise from acquisition system. The spectral difference coefficient was theoretically proved to have a guiding significance for wavelength selection. After theoretical analysis, the multi-band spectral difference coefficient-wavelength selection method combining with the dynamic spectrum was proposed. An experimental analysis based on clinical trial data from 200 volunteers has been conducted to illustrate the effectiveness of this method. The extreme learning machine was used to develop the calibration models between the dynamic spectrum data and hemoglobin concentration. The experiment result shows that the prediction precision of hemoglobin concentration using multi-band spectral difference coefficient-wavelength selection method is higher compared with other methods.

  20. Different conformational dynamics of β-arrestin1 and β-arrestin2 analyzed by hydrogen/deuterium exchange mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Yun, Youngjoo; Kim, Dong Kyun [School of Pharmacy, Sungkyunkwan University, Suwon (Korea, Republic of); Seo, Min-Duk [College of Pharmacy & Department of Molecular Science and Technology, Ajou University, Suwon (Korea, Republic of); Kim, Kyeong-Man [College of Pharmacy, Chonnam National University, Gwang-Ju (Korea, Republic of); Chung, Ka Young, E-mail: kychung2@skku.edu [School of Pharmacy, Sungkyunkwan University, Suwon (Korea, Republic of)

    2015-01-30

    Highlights: • The conformational dynamics of β-arrestin1 or β-arrestin2 were analyzed by HDX-MS. • β-Strands II through IV were more dynamic in β-arrestin2 than in β-arrestin1. • The middle loop was less dynamic in β-arrestin2 than in β-arrestin1. • Upon pre-activation by the R169E mutation, β-arrestins became more dynamic. • Pre-activation affected a wider region of β-arrestin1 compared to β-arrestin2. - Abstract: Arrestins have important roles in G protein-coupled receptor (GPCR) signaling including desensitization of GPCRs and G protein-independent signaling. There have been four arrestins identified: arrestin1, arrestin2 (e.g. β-arrestin1), arrestin3 (e.g. β-arrestin2), and arrestin4. β-Arrestin1 and β-arrestin2 are ubiquitously expressed and regulate a broad range of GPCRs, while arrestin1 and arrestin4 are expressed in the visual system. Although the functions of β-arrestin1 and β-arrestin2 widely overlap, β-arrestin2 has broader receptor selectivity, and a few studies have suggested that β-arrestin1 and β-arrestin2 have distinct cellular functions. Here, we compared the conformational dynamics of β-arrestin1 and β-arrestin2 by hydrogen/deuterium exchange mass spectrometry (HDX-MS). We also used the R169E mutant as a pre-activation model system. HDX-MS data revealed that β-strands II through IV were more dynamic in β-arrestin2 in the basal state, while the middle loop was more dynamic in β-arrestin1. With pre-activation, both β-arrestin1 and β-arrestin2 became more flexible, but broader regions of β-arrestin1 became flexible compared to β-arrestin2. The conformational differences between β-arrestin1 and β-arrestin2 in both the basal and pre-activated states might determine their different receptor selectivities and different cellular functions.

  1. The internal processes and behavioral dynamics of hospital boards: an exploration of differences between high- and low-performing hospitals.

    Science.gov (United States)

    Kane, Nancy M; Clark, Jonathan R; Rivenson, Howard L

    2009-01-01

    Nonprofit hospital boards are under increasing pressure to improve financial, clinical, and charitable and community benefit performance. Most research on board effectiveness focuses on variables measuring board structure and attributes associated with competing ideal models of board roles. However, the results do not provide clear evidence that one role is superior to another and suggest that in practice boards pursue hybrid roles. Board dynamics and processes have received less attention from researchers, but emerging theoretical frameworks highlight them as key to effective corporate governance. We explored differences in board processes and behavioral dynamics between financially high- and low-performing hospitals, with the goal of developing a better understanding of the best board practices in nonprofit hospitals. A comparative case study approach allowed for in-depth, qualitative assessments of how the internal workings of boards differ between low- and high-performing facilities. Boards of hospitals with strong financial performance exhibited behavioral dynamics and internal processes that differed in important ways from those of hospitals with poor financial performance. Boards need to actively attend to key processes and foster positive group dynamics in decision making to be more effective in governing hospitals.

  2. "Isocrater" impacts: Conditions and mantle dynamical responses for different impactor types

    Science.gov (United States)

    Ruedas, Thomas; Breuer, Doris

    2018-05-01

    Impactors of different types and sizes can produce a final crater of the same diameter on a planet under certain conditions. We derive the condition for such "isocrater impacts" from scaling laws, as well as relations that describe how the different impactors affect the interior of the target planet; these relations are also valid for impacts that are too small to affect the mantle. The analysis reveals that in a given isocrater impact, asteroidal impactors produce anomalies in the interior of smaller spatial extent than cometary or similar impactors. The differences in the interior could be useful for characterizing the projectile that formed a given crater on the basis of geophysical observations and potentially offer a possibility to help constrain the demographics of the ancient impactor population. A series of numerical models of basin-forming impacts on Mercury, Venus, the Moon, and Mars illustrates the dynamical effects of the different impactor types on different planets. It shows that the signature of large impacts may be preserved to the present in Mars, the Moon, and Mercury, where convection is less vigorous and much of the anomaly merges with the growing lid. On the other hand, their signature will long have been destroyed in Venus, whose vigorous convection and recurring lithospheric instabilities obliterate larger coherent anomalies.

  3. New evidence for strategic differences between static and dynamic search tasks: An individual observer analysis of eye movements

    Directory of Open Access Journals (Sweden)

    Christopher eDickinson

    2013-01-01

    Full Text Available Two experiments are reported that further explore the processes underlying dynamic search. In Experiment 1, observers’ oculomotor behavior was monitored while they searched for a randomly oriented T among oriented L distractors under static and dynamic viewing conditions. Despite similar search slopes, eye movements were less frequent and more spatially constrained under dynamic viewing relative to static, with misses also increasing more with target eccentricity in the dynamic condition. These patterns suggest that dynamic search involves a form of sit-and-wait strategy in which search is restricted to a small group of items surrounding fixation. To evaluate this interpretation, we developed a computational model of a sit-and-wait process hypothesized to underlie dynamic search. In Experiment 2 we tested this model by varying fixation position in the display and found that display positions optimized for a sit-and-wait strategy resulted in higher d' values relative to a less optimal location. We conclude that different strategies, and therefore underlying processes, are used to search static and dynamic displays.

  4. Solving the dynamic rupture problem with different numerical approaches and constitutive laws

    Science.gov (United States)

    Bizzarri, A.; Cocco, M.; Andrews, D.J.; Boschi, Enzo

    2001-01-01

    We study the dynamic initiation, propagation and arrest of a 2-D in-plane shear rupture by solving the elastodynamic equation by using both a boundary integral equation method and a finite difference approach. For both methods we adopt different constitutive laws: a slip-weakening (SW) law, with constant weakening rate, and rate- and state-dependent friction laws (Dieterich-Ruina). Our numerical procedures allow the use of heterogeneous distributions of constitutive parameters along the fault for both formulations. We first compare the two solution methods with an SW law, emphasizing the required stability conditions to achieve a good resolution of the cohesive zone and to avoid artificial complexity in the solutions. Our modelling results show that the two methods provide very similar time histories of dynamic source parameters. We point out that, if a careful control of resolution and stability is performed, the two methods yield identical solutions. We have also compared the rupture evolution resulting from an SW and a rate- and state-dependent friction law. This comparison shows that despite the different constitutive formulations, a similar behaviour is simulated during the rupture propagation and arrest. We also observe a crack tip bifurcation and a jump in rupture velocity (approaching the P-wave speed) with the Dieterich-Ruina (DR) law. The rupture arrest at a barrier (high strength zone) and the barrier-healing mechanism are also reproduced by this law. However, this constitutive formulation allows the simulation of a more general and complex variety of rupture behaviours. By assuming different heterogeneous distributions of the initial constitutive parameters, we are able to model a barrier-healing as well as a self-healing process. This result suggests that if the heterogeneity of the constitutive parameters is taken into account, the different healing mechanisms can be simulated. We also study the nucleation phase duration Tn, defined as the time

  5. Static and Dynamic Criticality: Are They Different?

    International Nuclear Information System (INIS)

    Cullen, D E; Clouse, C J; Procassini, R; Little, R C

    2003-01-01

    Let us start by stating that this paper does not contain anything new. It only contains material that has been known for decades, but which is periodically forgotten. As such this paper is intended merely to refresh people's memories. We will also mention that this paper is an example of the occasional discrepancy between textbook methodologies and real world applications, in the sense that the conclusions reached here contradict what it says in most textbooks, i.e., most textbooks incorrectly interpret the methods presented here, particularly with respect to the use of importance sampling to maintain population control. This paper is not intended as a general tutorial on criticality calculations. It is intended only to clarify the accuracy of various methods for solving criticality problems, such as a true time dependent dynamic calculation, versus an alpha or K static calculation. In particular, we address the long standing controversy between users of the TART code [1] with the dynamic method, and users of the MCNP code [2] with the alpha static method. In this paper we will prove which methods are accurate and inaccurate

  6. Sex difference and Allee effects shape the dynamics of sex-structured invasions.

    Science.gov (United States)

    Shaw, Allison K; Kokko, Hanna; Neubert, Michael G

    2018-01-01

    The rate at which a population grows and spreads can depend on individual behaviour and interactions with others. In many species with two sexes, males and females differ in key life-history traits (e.g. growth, survival and dispersal), which can scale up to affect population rates of growth and spread. In sexually reproducing species, the mechanics of locating mates and reproducing successfully introduce further complications for predicting the invasion speed (spread rate), as both can change nonlinearly with density. Most models of population spread are based on one sex, or include limited aspects of sex differences. Here we ask whether and how the dynamics of finding mates interact with sex-specific life-history traits to influence the rate of population spread. We present a hybrid approach for modelling invasions of populations with two sexes that links individual-level mating behaviour (in an individual-based model) to population-level dynamics (in an integrodifference equation model). We find that limiting the amount of time during which individuals can search for mates causes a demographic Allee effect which can slow, delay, or even prevent an invasion. Furthermore, any sex-based asymmetries in life history or behaviour (skewed sex ratio, sex-biased dispersal, and sex-specific mating behaviours) amplify these effects. In contrast, allowing individuals to mate more than once ameliorates these effects, enabling polygynandrous populations to invade under conditions where monogamously mating populations would fail to establish. We show that details of individuals' mating behaviour can impact the rate of population spread. Based on our results, we propose a stricter definition of a mate-finding Allee effect, which is not met by the commonly used minimum mating function. Our modelling approach, which links individual- and population-level dynamics in a single model, may be useful for exploring other aspects of individual behaviour that are thought to impact the

  7. Building energy performance analysis by an in-house developed dynamic simulation code: An investigation for different case studies

    International Nuclear Information System (INIS)

    Buonomano, Annamaria; Palombo, Adolfo

    2014-01-01

    Highlights: • A new dynamic simulation code for building energy performance analysis is presented. • The thermal behavior of each building element is modeled by a thermal RC network. • The physical models implemented in the code are illustrated. • The code was validated by the BESTEST standard procedure. • We investigate residential buildings, offices and stores in different climates. - Abstract: A novel dynamic simulation model for the building envelope energy performance analysis is presented in this paper. This tool helps the investigation of many new building technologies to increase the system energy efficiency and it can be carried out for scientific research purposes. In addition to the yearly heating and cooling load and energy demand, the obtained output is the dynamic temperature profile of indoor air and surfaces and the dynamic profile of the thermal fluxes through the building elements. The presented simulation model is also validated through the BESTEST standard procedure. Several new case studies are developed for assessing, through the presented code, the energy performance of three different building envelopes with several different weather conditions. In particular, dwelling and commercial buildings are analysed. Light and heavyweight envelopes as well as different glazed surfaces areas have been used for every case study. With the achieved results interesting design and operating guidelines can be obtained. Such data have been also compared vs. those calculated by TRNSYS and EnergyPlus. The detected deviation of the obtained results vs. those of such standard tools are almost always lower than 10%

  8. Molecular Dynamics and Monte Carlo simulations resolve apparent diffusion rate differences for proteins confined in nanochannels

    Energy Technology Data Exchange (ETDEWEB)

    Tringe, J.W., E-mail: tringe2@llnl.gov [Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, CA (United States); Ileri, N. [Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, CA (United States); Department of Chemical Engineering & Materials Science, University of California, Davis, CA (United States); Levie, H.W. [Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, CA (United States); Stroeve, P.; Ustach, V.; Faller, R. [Department of Chemical Engineering & Materials Science, University of California, Davis, CA (United States); Renaud, P. [Swiss Federal Institute of Technology, Lausanne, (EPFL) (Switzerland)

    2015-08-18

    Highlights: • WGA proteins in nanochannels modeled by Molecular Dynamics and Monte Carlo. • Protein surface coverage characterized by atomic force microscopy. • Models indicate transport characteristics depend strongly on surface coverage. • Results resolve of a four orders of magnitude difference in diffusion coefficient values. - Abstract: We use Molecular Dynamics and Monte Carlo simulations to examine molecular transport phenomena in nanochannels, explaining four orders of magnitude difference in wheat germ agglutinin (WGA) protein diffusion rates observed by fluorescence correlation spectroscopy (FCS) and by direct imaging of fluorescently-labeled proteins. We first use the ESPResSo Molecular Dynamics code to estimate the surface transport distance for neutral and charged proteins. We then employ a Monte Carlo model to calculate the paths of protein molecules on surfaces and in the bulk liquid transport medium. Our results show that the transport characteristics depend strongly on the degree of molecular surface coverage. Atomic force microscope characterization of surfaces exposed to WGA proteins for 1000 s show large protein aggregates consistent with the predicted coverage. These calculations and experiments provide useful insight into the details of molecular motion in confined geometries.

  9. Numerical Simulation of the Dynamic Performance of the Ceramic Material Affected by Different Strain Rate and Porosity

    International Nuclear Information System (INIS)

    Wang Zhen; Mei, H; Lai, X; Liu, L S; Zhai, P C; Cao, D F

    2013-01-01

    Ceramic materials are frequently used in protective armor applications for its low-density, high elastic modulus and high strength. It may be subject to different ballistic impacts in many situations, thus many studies have been carried out to explore the approach to improve the mechanical properties of the ceramic material. However, the materials manufactured in real world are full of defects, which would involve in variable fractures or damage. Therefore, the defects should be taken into account while the simulations are performed. In this paper, the dynamic properties of ceramic materials (Al 2 O 3 ) affected by different strain rate (500–5000) and porosity (below 5%) are investigated. Foremost, the effect of strain rate was studied by using different load velocities. Then, compression simulations are performed by setting different porosities and random distribution of pores size and location in ceramic materials. Crack extensions and failure modes are observed to describe the dynamic mechanical behavior.

  10. Temperature-dependent dynamical transitions of different classes of amino acid residue in a globular protein.

    Science.gov (United States)

    Miao, Yinglong; Yi, Zheng; Glass, Dennis C; Hong, Liang; Tyagi, Madhusudan; Baudry, Jerome; Jain, Nitin; Smith, Jeremy C

    2012-12-05

    The temperature dependences of the nanosecond dynamics of different chemical classes of amino acid residue have been analyzed by combining elastic incoherent neutron scattering experiments with molecular dynamics simulations on cytochrome P450cam. At T = 100-160 K, anharmonic motion in hydrophobic and aromatic residues is activated, whereas hydrophilic residue motions are suppressed because of hydrogen-bonding interactions. In contrast, at T = 180-220 K, water-activated jumps of hydrophilic side chains, which are strongly coupled to the relaxation rates of the hydrogen bonds they form with hydration water, become apparent. Thus, with increasing temperature, first the hydrophobic core awakens, followed by the hydrophilic surface.

  11. Comparative Analysis of Gender Differences in the HIV-1 Infection Dynamics

    Science.gov (United States)

    Ballesteros, P.; Estrada, J. L.; Barriga, G.; Molinar, F.; Hernández, M. C.; Huerta, L.; Cocho, G.; Villarreal, C.

    2006-09-01

    We have performed a retrospective study of the HIV-1 viral load and CD4 T-cell counts in blood plasma of more than 3000 Mexican patients. We found that women had consistently lower viral loads than men for CD4 T-cell counts higher than 50 cells/μL and higher viral loads when CD4 T-cell counts were at most 50 cells/μL. Our results show the same pattern as the one reported in studies performed in European and North American populations. We present theoretical predictions of viral load dynamics during highly active antiretroviral therapy taking into account gender differences.

  12. EEG neural oscillatory dynamics reveal semantic and response conflict at difference levels of conflict awareness

    OpenAIRE

    Jun Jiang; Qinglin Zhang; Simon Van Gaal

    2015-01-01

    Although previous work has shown that conflict can be detected in the absence of awareness, it is unknown how different sources of conflict (i.e., semantic, response) are processed in the human brain and whether these processes are differently modulated by conflict awareness. To explore this issue, we extracted oscillatory power dynamics from electroencephalographic (EEG) data recorded while human participants performed a modified version of the Stroop task. Crucially, in this task conflict a...

  13. Parenting and Child Characteristics in the Prediction of Shame in Early and Middle Childhood

    Science.gov (United States)

    Mills, Rosemary S. L.; Arbeau, Kimberley A.; Lall, Debra I. K.; De Jaeger, Amy E.

    2010-01-01

    We examined individual differences in shame responding in early childhood and predictive relations with shame proneness in middle childhood. Child shame responding, parental shaming, and child temperamental inhibition were assessed at Time 1 (n = 225, aged 3-4 years), shame responding was reassessed at Time 2 (n = 199, aged 5-7 years), and shame…

  14. Research of thermal dynamic characteristics for variable load single screw refrigeration compressor with different capacity control mechanism

    International Nuclear Information System (INIS)

    Wang, Zengli; Wang, Zhenbo; Wang, Jun; Jiang, Wenchun; Feng, Quanke

    2017-01-01

    Highlights: • Theoretical models of SSRC under part-load condition have been established. • The experiment of SSRC performance under part-load condition was conducted. • Thermal dynamic characteristic of SSRC under part-load condition was gained. • Economy and reliability of SSRC under part-load condition was analyzed. - Abstract: In the single screw refrigeration compressor (SSRC), the capacity control mechanism is normally employed to meet the actual required cooling capacity under different load conditions. In this paper, theoretical calculation models describing the working process of the SSRC with the single slide valve capacity control mechanism (SVCCM) and SSRC with the frequency conversion regulating mechanism (FCRM) are established to research the thermal dynamic characteristics for variable load SSRC under part-load conditions. Experimental investigation on a SSRC under part-load conditions is also carried out to verify the theoretical calculation models. By using these validated models, the thermodynamic performances and dynamic characteristics of the SSRC with different capacity control mechanism under part-load conditions have been analyzed and compared. Through the comparison, the economical efficiency and reliability of the SSRC with different capacity control mechanism were obtained. All of these works can provide the basis for the later optimization design for the variable load single screw refrigeration compressor.

  15. Developmental aspects of borderline personality disorder.

    Science.gov (United States)

    Reich, D B; Zanarini, M C

    2001-01-01

    This study examined whether patients with borderline personality disorder and controls with other personality disorders remember their childhoods differently with respect to separation difficulties, evocative memory, temperamental factors such as frustration tolerance and mood reactivity, and onset of symptoms. Two hundred and ninety patients with borderline personality disorder and 72 with other personality disorders were assessed using an instrument to rate memories of separation difficulties, temperamental problems, and onset of symptoms before age 18. Patients with borderline personality disorder remembered more difficulties with separation between ages 6 and 17 years, more mood reactivity and poorer frustration tolerance between ages 6 and 17, and the onset of more symptoms (most prominently sadness, depression, anxiety, and suicidality) before age 18 than did patients with other personality disorders. The groups did not differ in reports of evocative memory before age 18. These results indicate that many of the features of adult patients with borderline personality disorder may initially appear during childhood and adolescence and that these features may be used to differentiate borderline from other personality disorders.

  16. Structure and dynamics of TIP3P, TIP4P, and TIP5P water near smooth and atomistic walls of different hydroaffinity

    International Nuclear Information System (INIS)

    Harrach, Michael F.; Drossel, Barbara

    2014-01-01

    We perform molecular dynamics simulations to observe the structure and dynamics of water using different water models (TIP3P, TIP4P, TIP5P) at ambient conditions, constrained by planar walls, which are either modeled by smooth potentials or regular atomic lattices, imitating the honeycomb-structure of graphene. We implement walls of different hydroaffinity, different lattice constant, and different types of interaction with the water molecules. We find that in the hydrophobic regime the smooth wall generally represents a good abstraction of the atomically rough walls, while in the hydrophilic regime there are noticeable differences in structure and dynamics between all stages of wall roughness. For a small lattice constant however the smooth and the atomically rough wall still share a number of structural and dynamical similarities. Out of the three water models, TIP5P water shows the largest degree of tetrahedral ordering and is often the one that is least perturbed by the presence of the wall

  17. Dynamic behavior of a nonlinear rational difference equation and generalization

    Directory of Open Access Journals (Sweden)

    Shi Qihong

    2011-01-01

    Full Text Available Abstract This paper is concerned about the dynamic behavior for the following high order nonlinear difference equation x n = (x n-k + x n-m + x n-l /(x n-k x n-m + x n-m x n-l +1 with the initial data { x - l , x - l + 1 , … , x - 1 } ∈ ℝ + l and 1 ≤ k ≤ m ≤ l. The convergence of solution to this equation is investigated by introducing a new sequence, which extends and includes corresponding results obtained in the references (Li in J Math Anal Appl 312:103-111, 2005; Berenhaut et al. Appl. Math. Lett. 20:54-58, 2007; Papaschinopoulos and Schinas J Math Anal Appl 294:614-620, 2004 to a large extent. In addition, some propositions for generalized equations are reported.

  18. Identification of different processes in magnetization dynamics of API steels using magnetic Barkhausen noise

    International Nuclear Information System (INIS)

    Pérez-Benítez, J A; Espina-Hernández, J H; Le Man, Tu; Caleyo, F; Hallen, J M

    2015-01-01

    This work presents a method to identify processes in magnetization dynamics using the angular dependence of the magnetic Barkhausen noise. The analysis reveals that three different processes of the magnetization dynamics could be identified using the angular dependence of the magnetic Barkhausen noise energy. The first process is the reversed domain nucleation which is related to the magneto-crystalline energy of the material, and the second and third ones are associated with 180° and 90° domain walls motions, respectively. Additionally, two transition regions were identified and they are located between the regions associated with the aforementioned processes. The causes involving these processes are analyzed and a method for establishing their location in the Barkhausen noise signal with respect to the applied magnetic field intensity is proposed. (paper)

  19. Differences in postural tremor dynamics with age and neurological disease.

    Science.gov (United States)

    Morrison, Steven; Newell, Karl M; Kavanagh, Justin J

    2017-06-01

    The overlap of dominant tremor frequencies and similarly amplified tremor observed for Parkinson's disease (PD) and essential tremor (ET) means differentiating between these pathologies is often difficult. As tremor exhibits non-linear properties, employing both linear and non-linear analyses may help distinguish between the tremor dynamics of aging, PD and ET. This study was designed to examine postural tremor in healthy older adults, PD and ET using standard linear and non-linear metrics. Hand and finger postural tremor was recorded in 15 healthy older adults (64 ± 6 years), 15 older individuals with PD (63 ± 6 years), and 10 persons with ET (68 ± 7 years). Linear measures of amplitude, frequency, and between-limb coupling (coherence) were performed. Non-linear measures of regularity (ApEn) and coupling (Cross-ApEn) were also used. Additionally, receiver operating characteristic analyses were performed for those measures that were significantly different between all groups. The results revealed that the linear measures only showed significant differences between the healthy adults and ET/PD persons, but no differences between the two neurological groups. Coherence showed higher bilateral coupling for ET but no differences in inter-limb coupling between PD and healthy subjects. However, ApEn values for finger tremor revealed significant differences between all groups, with tremor for ET persons being more regular (lower ApEn) overall. Similarly, Cross-ApEn results also showed differences between all groups, with ET persons showing strongest inter-limb coupling followed by PD and elderly. Overall, our findings point to the diagnostic potential for non-linear measures of coupling and tremor structure as biomarkers for discriminating between ET, PD and healthy persons.

  20. Paradoxical differences in N-dynamics between Luxembourg soils: litter quality or parent material?

    OpenAIRE

    Kooijman, A.M.; Smit, A.

    2009-01-01

    To explore whether litter quality could alter differences in N-dynamics between soil types, we compared spruce and beech growing on soils with parent material sandstone and limestone, and beech and hornbeam on acid marl and limestone. We measured pH, organic matter content, C:N ratio, soil respiration and net N-mineralization of the organic layer and the mineral topsoil in a laboratory incubation experiment and estimated gross N-mineralization and immobilization with a simulation model. Speci...

  1. Pathological manifestation of difference in washout pattern of adrenal hyperplasia on dynamic CT

    International Nuclear Information System (INIS)

    Nishie, Akihiro; Asayama, Yoshiki; Ishigami, Kousei

    2014-01-01

    The relationship between the washout pattern and constituent cell in adrenal hyperplasia (AH) has not been fully investigated. The purpose of this study was to elucidate the radiological or pathological factors determining the washout pattern of AH on dynamic CT. Ten patients with 14 surgically proven AHs were enrolled. Dynamic CT was scanned before (pre-contrast image) and 60 seconds (early phase) and 240 seconds (delayed phase) after administration of iodine contrast. The absolute percentage washout (APW) of each nodular lesion was calculated using the following formula: APW(%)=(TAearly-TAdelay) / (TAearly-TApre)×100, when TApre, TAearly and TAdelay were defined as tumour attenuation values of pre-contrast, early and delayed phases, respectively. Pathologically, the clear cell ratio (CCR) constituting each nodular lesion was qualitatively assessed. Regression analysis was performed to evaluate a correlation between each pair of CCR, TApre, (TAearly-TAdelay) and APW. There was a significant correlation between each pair of CCR, TApre and APW. CCR decreased as TApre increased (r=0.81, P<0.001). APW increased as CCR decreased r=0.80, P<0.001) or as TApre increased (r=0.74, P<0.01). The key factors of washout pattern of AH on dynamic CT were CCR and TApre. The difference in constituent cell was associated with variability in APW of AH.

  2. Collateral ventilation quantification using xenon-enhanced dynamic dual-energy CT: Differences between canine and swine models of bronchial occlusion

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Eun Ah; Goo, Jin Mo; Park, Sang Joon; Lee, Chang Hyun; Park, Chng Min [Dept. of Radiology, Seoul National University College of Medicine and Institute of Radiation Medicine, Seoul National University Medical Research Center, Seoul (Korea, Republic of)

    2015-06-15

    The aim of this study was to evaluate whether the difference in the degree of collateral ventilation between canine and swine models of bronchial obstruction could be detected by using xenon-enhanced dynamic dual-energy CT. Eight mongrel dogs and six pigs underwent dynamic dual-energy scanning of 64-slice dual-source CT at 12-second interval for 2-minute wash-in period (60% xenon) and at 24-second interval for 3-minute wash-out period with segmental bronchus occluded. Ventilation parameters of magnitude (A value), maximal slope, velocity (K value), and time-to-peak (TTP) enhancement were calculated from dynamic xenon maps using exponential function of Kety model. A larger difference in A value between parenchyma was observed in pigs than in dogs (absolute difference, -33.0 +/- 5.0 Hounsfield units [HU] vs. -2.8 +/- 7.1 HU, p = 0.001; normalized percentage difference, -79.8 +/- 1.8% vs. -5.4 +/- 16.4%, p = 0.0007). Mean maximal slopes in both periods in the occluded parenchyma only decreased in pigs (all p < 0.05). K values of both periods were not different (p = 0.892) in dogs. However, a significant (p = 0.027) difference was found in pigs in the wash-in period. TTP was delayed in the occluded parenchyma in pigs (p = 0.013) but not in dogs (p = 0.892). Xenon-ventilation CT allows the quantification of collateral ventilation and detection of differences between canine and swine models of bronchial obstruction.

  3. Collateral ventilation quantification using xenon-enhanced dynamic dual-energy CT: Differences between canine and swine models of bronchial occlusion

    International Nuclear Information System (INIS)

    Kim, Eun Ah; Goo, Jin Mo; Park, Sang Joon; Lee, Chang Hyun; Park, Chng Min

    2015-01-01

    The aim of this study was to evaluate whether the difference in the degree of collateral ventilation between canine and swine models of bronchial obstruction could be detected by using xenon-enhanced dynamic dual-energy CT. Eight mongrel dogs and six pigs underwent dynamic dual-energy scanning of 64-slice dual-source CT at 12-second interval for 2-minute wash-in period (60% xenon) and at 24-second interval for 3-minute wash-out period with segmental bronchus occluded. Ventilation parameters of magnitude (A value), maximal slope, velocity (K value), and time-to-peak (TTP) enhancement were calculated from dynamic xenon maps using exponential function of Kety model. A larger difference in A value between parenchyma was observed in pigs than in dogs (absolute difference, -33.0 +/- 5.0 Hounsfield units [HU] vs. -2.8 +/- 7.1 HU, p = 0.001; normalized percentage difference, -79.8 +/- 1.8% vs. -5.4 +/- 16.4%, p = 0.0007). Mean maximal slopes in both periods in the occluded parenchyma only decreased in pigs (all p < 0.05). K values of both periods were not different (p = 0.892) in dogs. However, a significant (p = 0.027) difference was found in pigs in the wash-in period. TTP was delayed in the occluded parenchyma in pigs (p = 0.013) but not in dogs (p = 0.892). Xenon-ventilation CT allows the quantification of collateral ventilation and detection of differences between canine and swine models of bronchial obstruction.

  4. Dynamics of second order rational difference equations with open problems and conjectures

    CERN Document Server

    Kulenovic, Mustafa RS

    2001-01-01

    This self-contained monograph provides systematic, instructive analysis of second-order rational difference equations. After classifying the various types of these equations and introducing some preliminary results, the authors systematically investigate each equation for semicycles, invariant intervals, boundedness, periodicity, and global stability. Of paramount importance in their own right, the results presented also offer prototypes towards the development of the basic theory of the global behavior of solutions of nonlinear difference equations of order greater than one. The techniques and results in this monograph are also extremely useful in analyzing the equations in the mathematical models of various biological systems and other applications. Each chapter contains a section of open problems and conjectures that will stimulate further research interest in working towards a complete understanding of the dynamics of the equation and its functional generalizations-many of them ideal for research project...

  5. Experiments with mathematical models to simulate hepatitis A population dynamics under different levels of endemicity

    Directory of Open Access Journals (Sweden)

    Mariana Alves de Guimaraens

    Full Text Available Heterogeneous access to sanitation services is a characteristic of communities in Brazil. This heterogeneity leads to different patterns of hepatitis A endemicity: areas with low infection rates have higher probability of outbreaks, and areas with higher infection rates have high prevalence and low risk of outbreaks. Here we develop a mathematical model to study the effect of variable exposure to infection on the epidemiological dynamics of hepatitis A. Differential equations were used to simulate population dynamics and were numerically solved using the software StellaTM. The model uses parameters from serological surveys in the Greater Metropolitan Rio de Janeiro, in areas with different sanitation conditions. Computer simulation experiments show that the range of infection rates observed in these communities are characteristic of high and low levels of hepatitis A endemicity. We also found that the functional relationship between sanitation and exposure to infection is an important component of the model. The analysis of the public health impact of partial sanitation requires a better understanding of this relationship.

  6. Solution Method and Precision Analysis of Double-difference Dynamic Precise Orbit Determination of BeiDou Navigation Satellite System

    Directory of Open Access Journals (Sweden)

    LIU Weiping

    2016-02-01

    Full Text Available To resolve the high relativity between the transverse element of GEO orbit and double-difference ambiguity, the classical double-difference dynamic method is improved and the method, which is to determine precise BeiDou satellite orbit using carrier phase and pseudo-range smoothed by phase, is proposed. The feasibility of the method is discussed and the influence of the method about ambiguity fixing is analyzed. Considering the characteristic of BeiDou, the method, which is to fix double-difference ambiguity of BeiDou satellites by QIF, is derived. The real data analysis shows that the new method, which can reduce the relativity and assure the precision, is better than the classical double-difference dynamic method. The result of ambiguity fixing is well by QIF, but the ambiguity fixing success rate is not high on the whole. So the precision of BeiDou orbit can't be improved clearly after ambiguity fixing.

  7. Modeling detour behavior of pedestrian dynamics under different conditions

    Science.gov (United States)

    Qu, Yunchao; Xiao, Yao; Wu, Jianjun; Tang, Tao; Gao, Ziyou

    2018-02-01

    Pedestrian simulation approach has been widely used to reveal the human behavior and evaluate the performance of crowd evacuation. In the existing pedestrian simulation models, the social force model is capable of predicting many collective phenomena. Detour behavior occurs in many cases, and the important behavior is a dominate factor of the crowd evacuation efficiency. However, limited attention has been attracted for analyzing and modeling the characteristics of detour behavior. In this paper, a modified social force model integrated by Voronoi diagram is proposed to calculate the detour direction and preferred velocity. Besides, with the consideration of locations and velocities of neighbor pedestrians, a Logit-based choice model is built to describe the detour direction choice. The proposed model is applied to analyze pedestrian dynamics in a corridor scenario with either unidirectional or bidirectional flow, and a building scenario in real-world. Simulation results show that the modified social force model including detour behavior could reduce the frequency of collision and deadlock, increase the average speed of the crowd, and predict more practical crowd dynamics with detour behavior. This model can also be potentially applied to understand the pedestrian dynamics and design emergent management strategies for crowd evacuations.

  8. Effect of temperament on cortisol response to a single exercise bout in Thoroughbred racehorses - short communication.

    Science.gov (United States)

    Bohák, Zsófia; Szenci, Ottó; Harnos, Andrea; Kutasi, Orsolya; Kovács, Levente

    2017-12-01

    Temperament has not been taken into account in previous studies evaluating the stress response to exercise in horses. The aim of the present study was to investigate the cortisol response in Thoroughbred racehorses to a single exercise bout, and to analyse the results based on the basic personality of the horse examined. Twenty healthy Thoroughbred horses were selected for the study based on a 25-item rating questionnaire survey used for characterising equine temperament. Eight temperamental and twelve calm horses took part in the experiment. The horses trotted as a warm-up activity, and then galloped on a rounded sand track. Blood sampling was conducted four times for each horse. Horses with a more excitable temperament showed a higher cortisol response to the test (P = 0.036). In conclusion, cortisol levels in response to a mild intensive exercise can be affected by temperament in horses. Serum cortisol may be a relevant marker to quantify individual temperamental differences in racehorses.

  9. Simulations of Operation Dynamics of Different Type GaN Particle Sensors

    Science.gov (United States)

    Gaubas, Eugenijus; Ceponis, Tomas; Kalesinskas, Vidas; Pavlov, Jevgenij; Vysniauskas, Juozas

    2015-01-01

    The operation dynamics of the capacitor-type and PIN diode type detectors based on GaN have been simulated using the dynamic and drift-diffusion models. The drift-diffusion current simulations have been implemented by employing the software package Synopsys TCAD Sentaurus. The monopolar and bipolar drift regimes have been analyzed by using dynamic models based on the Shockley-Ramo theorem. The carrier multiplication processes determined by impact ionization have been considered in order to compensate carrier lifetime reduction due to introduction of radiation defects into GaN detector material. PMID:25751080

  10. Foot deformation during walking: differences between static and dynamic 3D foot morphology in developing feet.

    Science.gov (United States)

    Barisch-Fritz, Bettina; Schmeltzpfenning, Timo; Plank, Clemens; Grau, Stefan

    2014-01-01

    The complex functions of feet require a specific composition, which is progressively achieved by developmental processes. This development should take place without being affected by footwear. The aim of this study is to evaluate differences between static and dynamic foot morphology in developing feet. Feet of 2554 participants (6-16 years) were recorded using a new scanner system (DynaScan4D). Each foot was recorded in static half and full weight-bearing and during walking. Several foot measures corresponding to those used in last construction were calculated. The differences were identified by one-way ANOVA and paired Student's t-test. Static and dynamic values of each foot measure must be considered to improve the fit of footwear. In particular, footwear must account for the increase of forefoot width and the decrease of midfoot girth. Furthermore, the toe box should have a more rounded shape. The findings are important for the construction of footwear for developing feet.

  11. Absorbed dose to the urinary bladder wall for different radiopharmaceuticals using dynamic S-values

    International Nuclear Information System (INIS)

    Andersson, M.; Minarik, D.; Mattsson, S.; Leide-Svegborn; Johansson, L.

    2015-01-01

    Full text of publication follows. Aim and background: the urinary bladder wall is a radiosensitive organ that can receive a high absorbed dose from radiopharmaceuticals used in diagnostic nuclear medicine. Current dynamic models estimate the photon and electron absorbed dose at the inner surface of the bladder wall. The aim of this work has been to create a more realistic estimation of the mean absorbed dose to the urinary bladder wall from different radiopharmaceuticals. This calculation also uses dynamic specific absorption fractions (SAF) that changes with bladder volume and are gender specific. Materials and Methods: the volume of the urinary bladder content was calculated using a spherical approximation with a urinary inflow of 1.0 ml/min and 0.5 ml/min during day and night time, respectively. The activity in the bladder content was described using a bi-exponential extraction from the body. The absorbed dose to the bladder wall was estimated using linear interpolation of SAF values from different bladder volumes, ranging from 10 ml to 800 ml. Administration of the activity was assumed to start at 09:00 with an initial voiding after 40 minutes and a voiding interval of 3.5 hours during the day. A six hour night gap, starting at midnight, with a voiding right before and after the night period, was used. Calculations were made, with the same assumptions, for an earlier dynamic bladder model and with a static SAF value from the ICRP/ICRU adult reference computational phantoms for a bladder containing 200 ml. Values for the absorbed dose per unit administered activity for 19 commonly used radiopharmaceuticals were calculated, e.g. 18 F-FDG, 99m Tc-pertechnetate, 99m Tc-MAG3 and 123 I-NaI. Results and conclusion: the results of the estimates of the absorbed doses to the inner bladder wall were a factor of ten higher than the estimates mean absorbed doses. The mean absorbed doses to the bladder wall were slightly higher for females than males, due to a smaller female

  12. Molecular dynamics simulations of a fully hydrated dipalmitoyl phosphatidylcholine bilayer with different macroscopic boundary conditions and parameters

    NARCIS (Netherlands)

    Tieleman, D.P; Berendsen, H.J.C.

    1996-01-01

    We compared molecular dynamics simulations of a bilayer of 128 fully hydrated phospholipid (DPPC) molecules, using different parameters and macroscopic boundary conditions. The same system was studied under constant pressure, constant volume, and constant surface tension boundary conditions, with

  13. Molecular Dynamics Simulation of Solidification of Pd-Ni Clusters with Different Nickel Content

    Directory of Open Access Journals (Sweden)

    Chen Gang

    2014-01-01

    Full Text Available Molecular dynamics simulation has been performed for investigating the glass transition of Pd-Ni alloy nanoparticles in the solidification process. The results showed that the Pd-Ni nanoparticles with composition far from pure metal should form amorphous structure more easily, which is in accordance with the results of the thermodynamic calculation. There are some regular and distorted fivefold symmetry in the amorphous Pd-Ni alloy nanoparticles. The nanoclusters with bigger difference value between formation enthalpies of solutions and glasses will transform to glass more easily than the other Pd-Ni alloy nanoclusters.

  14. Hemodynamic Changes After Static and Dynamic Exercises and Treadmill Stress Test; Different Patterns in Patients with Primary Benign Exertional Headache?

    Directory of Open Access Journals (Sweden)

    Mohsen Rostami

    2012-06-01

    Full Text Available The pathophysiology of primary benign exertional headache (EH is not still clearly defined. Some researchers have suggested an impaired vascular response as the etiology of this disorder. In this study we investigated whether there are any differences in blood pressure (BP and heart rate (HR of the subjects in course of the static and dynamic exercises and the treadmill stress test between those with and without EH. From university students, 22 patients with EH (mean age: 19.8 ± 2.10, Female to Male: 7:15 and 20 normal subjects (mean age: 19.3 ± 1.97, Female: Male: 8:12 were recruited. All the subjects performed the static and dynamic exercises at 30 and 20 percent of the maximal voluntary contraction (MVC and Bruce treadmill stress test according to the standard protocols. HR and BP of all the cases at the baseline and during and immediately after each test were measured. No significant difference was found between the mean rise of HR, systolic and diastolic BP of the subjects with and without EH in static and dynamic exercises and also treadmill stress test. It seems that between those with and without EH, there is no significant difference in rise of HR and BP response to static and dynamic exercises and treadmill stress test. Further studies are required to find the pathophysiology and risk factors of EH.

  15. Hemodynamic changes after static and dynamic exercises and treadmill stress test; different patterns in patients with primary benign exertional headache?

    Science.gov (United States)

    Kordi, Ramin; Mazaheri, Reza; Rostami, Mohsen; Mansournia, Mohammad Ali

    2012-01-01

    The pathophysiology of primary benign exertional headache (EH) is not still clearly defined. Some researchers have suggested an impaired vascular response as the etiology of this disorder. In this study we investigated whether there are any differences in blood pressure (BP) and heart rate (HR) of the subjects in course of the static and dynamic exercises and the treadmill stress test between those with and without EH. From university students, 22 patients with EH (mean age: 19.8 ± 2.10, Female to Male: 7:15) and 20 normal subjects (mean age: 19.3 ± 1.97, Female: Male: 8:12) were recruited. All the subjects performed the static and dynamic exercises at 30 and 20 percent of the maximal voluntary contraction (MVC) and Bruce treadmill stress test according to the standard protocols. HR and BP of all the cases at the baseline and during and immediately after each test were measured. No significant difference was found between the mean rise of HR, systolic and diastolic BP of the subjects with and without EH in static and dynamic exercises and also treadmill stress test. It seems that between those with and without EH, there is no significant difference in rise of HR and BP response to static and dynamic exercises and treadmill stress test. Further studies are required to find the pathophysiology and risk factors of EH.

  16. EEG neural oscillatory dynamics reveal semantic and response conflict at difference levels of conflict awareness.

    Science.gov (United States)

    Jiang, Jun; Zhang, Qinglin; Van Gaal, Simon

    2015-07-14

    Although previous work has shown that conflict can be detected in the absence of awareness, it is unknown how different sources of conflict (i.e., semantic, response) are processed in the human brain and whether these processes are differently modulated by conflict awareness. To explore this issue, we extracted oscillatory power dynamics from electroencephalographic (EEG) data recorded while human participants performed a modified version of the Stroop task. Crucially, in this task conflict awareness was manipulated by masking a conflict-inducing color word preceding a color patch target. We isolated semantic from response conflict by introducing four color words/patches, of which two were matched to the same response. We observed that both semantic as well as response conflict were associated with mid-frontal theta-band and parietal alpha-band power modulations, irrespective of the level of conflict awareness (high vs. low), although awareness of conflict increased these conflict-related power dynamics. These results show that both semantic and response conflict can be processed in the human brain and suggest that the neural oscillatory mechanisms in EEG reflect mainly "domain general" conflict processing mechanisms, instead of conflict source specific effects.

  17. EEG neural oscillatory dynamics reveal semantic and response conflict at difference levels of conflict awareness

    Science.gov (United States)

    Jiang, Jun; Zhang, Qinglin; Van Gaal, Simon

    2015-01-01

    Although previous work has shown that conflict can be detected in the absence of awareness, it is unknown how different sources of conflict (i.e., semantic, response) are processed in the human brain and whether these processes are differently modulated by conflict awareness. To explore this issue, we extracted oscillatory power dynamics from electroencephalographic (EEG) data recorded while human participants performed a modified version of the Stroop task. Crucially, in this task conflict awareness was manipulated by masking a conflict-inducing color word preceding a color patch target. We isolated semantic from response conflict by introducing four color words/patches, of which two were matched to the same response. We observed that both semantic as well as response conflict were associated with mid-frontal theta-band and parietal alpha-band power modulations, irrespective of the level of conflict awareness (high vs. low), although awareness of conflict increased these conflict-related power dynamics. These results show that both semantic and response conflict can be processed in the human brain and suggest that the neural oscillatory mechanisms in EEG reflect mainly “domain general” conflict processing mechanisms, instead of conflict source specific effects. PMID:26169473

  18. Role of Nutrition in Children Growth in View of Traditional Medicine.

    Science.gov (United States)

    Farsani, Gholamreza Mohammadi; Movahhed, Mina

    2016-05-01

    Growth and development are the basic science in pediatric medicine. Growth disorder in children is one of the important health problems in the world, especially in developing countries. Regardless of the underlying disease, as the main cause of growth disorders, assessment and correction of nutritional status of these children are very important. Given the fundamental importance of this issue and ascending tendency to use complementary medicine in the world, this article discusses the traditional Iranian philosopher's views on the role of nutrition in child development. This study reviews textbooks of traditional medicine, particularly in the field of pediatric medicine with a focus on Canon of Medicine of Avicenna. Temperament is the physiological concept of the human body in traditional medicine and has an important role in health, diagnosis, and treatment of disease. Generally, children are born with warm and wet temperament that provides the best condition for growth. However, the personal temperament of each child determines growth, the need for a variety of food groups, and even physical activity. Different appetite and food preferences in children show temperamental variation. Therefore, children need special management regarding special temperament. In Iranian traditional medicine, special lifestyle orders are discussed in detail according to these differentiations and nutritional management is the most important factor considered. In spite of advances in classical medicine in the prevention and treatment of many diseases, there are still a lot of therapeutic challenges in many health problems. Temperamental approach to the human body in traditional medicine provides a different perspective on the medicine. Reflecting on temperamental view in child development may lead to a better understanding of the diagnosis and treatment of diseases. On the other hand, further research studies based on the reform of nutrition with respect to temperament should be

  19. On the Dynamic Robustness of a Non-Endoreversible Engine Working in Different Operation Regimes

    Directory of Open Access Journals (Sweden)

    Florencio Guzman-Aguilar

    2011-02-01

    Full Text Available In this work, we focused mainly in the analysis of stability of a non-endoreversible Curzon-Ahlborn engine working in an ecological regime. For comparison purposes we also include the Maximum Efficient Power (MEP regime taking into account the engine time delays. When the system’s dynamic stability is compared with its thermodynamics properties (efficiency and power output, we find that the temperature ratio τ = T1/T2 represents a trade-off between stability and energetic properties. When we take the non-endoreversible case, τ can increases to values greater than R (where R is the non-endoreversible parameter but not greater than one. We reformulate an important difference between this case and the other two, Maximum Power (MP and MEP regime, in which τ = R. Finally, we demonstrated that the total time delay does not destabilize the steady state of system. It does not seem to play a role in the dynamic thermodynamic property trade-off.

  20. Interdyad Differences in Early Mother-Infant Face-to-Face Communication: Real-Time Dynamics and Developmental Pathways

    Science.gov (United States)

    Lavelli, Manuela; Fogel, Alan

    2013-01-01

    A microgenetic research design with a multiple case study method and a combination of quantitative and qualitative analyses was used to investigate interdyad differences in real-time dynamics and developmental change processes in mother-infant face-to-face communication over the first 3 months of life. Weekly observations of 24 mother-infant dyads…

  1. Cholera and shigellosis in Bangladesh: similarities and differences in population dynamics under climate forcing

    Science.gov (United States)

    Pascual, M.; Cash, B.; Reiner, R.; King, A.; Emch, M.; Yunus, M.; Faruque, A. S.

    2012-12-01

    The influence of climate variability on the population dynamics of infectious diseases is considered a large scale, regional, phenomenon, and as such, has been previously addressed for cholera with temporal models that do not incorporate fine-scale spatial structure. In our previous work, evidence for a role of ENSO (El Niño Southern Oscillation) on cholera in Bangladesh was elucidated, and shown to influence the regional climate through precipitation. With a probabilistic spatial model for cholera dynamics in the megacity of Dhaka, we found that the action of climate variability (ENSO and flooding) is localized: there is a climate-sensitive urban core that acts to propagate risk to the rest of the city. Here, we consider long-term surveillance data for shigellosis, another diarrheal disease that coexists with cholera in Bangladesh. We compare the patterns of association with climate variables for these two diseases in a rural setting, as well as the spatial structure in their spatio-temporal dynamics in an urban one. Evidence for similar patterns is presented, and discussed in the context of the differences in the routes of transmission of the two diseases and the proposed role of an environmental reservoir in cholera. The similarities provide evidence for a more general influence of hydrology and of socio-economic factors underlying human susceptibility and sanitary conditions.

  2. Validation of the Regional Climate Model ALARO with different dynamical downscaling approaches and different horizontal resolutions

    Science.gov (United States)

    Berckmans, Julie; Hamdi, Rafiq; De Troch, Rozemien; Giot, Olivier

    2015-04-01

    At the Royal Meteorological Institute of Belgium (RMI), climate simulations are performed with the regional climate model (RCM) ALARO, a version of the ALADIN model with improved physical parameterizations. In order to obtain high-resolution information of the regional climate, lateral bounary conditions (LBC) are prescribed from the global climate model (GCM) ARPEGE. Dynamical downscaling is commonly done in a continuous long-term simulation, with the initialisation of the model at the start and driven by the regularly updated LBCs of the GCM. Recently, more interest exists in the dynamical downscaling approach of frequent reinitializations of the climate simulations. For these experiments, the model is initialised daily and driven for 24 hours by the GCM. However, the surface is either initialised daily together with the atmosphere or free to evolve continuously. The surface scheme implemented in ALARO is SURFEX, which can be either run in coupled mode or in stand-alone mode. The regional climate is simulated on different domains, on a 20km horizontal resolution over Western-Europe and a 4km horizontal resolution over Belgium. Besides, SURFEX allows to perform a stand-alone or offline simulation on 1km horizontal resolution over Belgium. This research is in the framework of the project MASC: "Modelling and Assessing Surface Change Impacts on Belgian and Western European Climate", a 4-year project funded by the Belgian Federal Government. The overall aim of the project is to study the feedbacks between climate changes and land surface changes in order to improve regional climate model projections at the decennial scale over Belgium and Western Europe and thus to provide better climate projections and climate change evaluation tools to policy makers, stakeholders and the scientific community.

  3. Compression dynamics of quasi-spherical wire arrays with different linear mass profiles

    International Nuclear Information System (INIS)

    Mitrofanov, K. N.; Aleksandrov, V. V.; Gritsuk, A. N.; Grabovski, E. V.; Frolov, I. N.; Laukhin, Ya. N.; Oleinik, G. M.; Ol’khovskaya, O. G.

    2016-01-01

    Results of experimental studies of the implosion of quasi-spherical wire (or metalized fiber) arrays are presented. The goal of the experiments was to achieve synchronous three-dimensional compression of the plasma produced in different regions of a quasi-spherical array into its geometrical center. To search for optimal synchronization conditions, quasi-spherical arrays with different initial profiles of the linear mass were used. The following dependences of the linear mass on the poloidal angle were used: m_l(θ) ∝ sin"–"1θ and m_l(θ) ∝ sin"–"2θ. The compression dynamics of such arrays was compared with that of quasi-spherical arrays without linear mass profiling, m_l(θ) = const. To verify the experimental data, the spatiotemporal dynamics of plasma compression in quasi-spherical arrays was studied using various diagnostics. The experiments on three-dimensional implosion of quasi-spherical arrays made it possible to study how the frozen-in magnetic field of the discharge current penetrates into the array. By measuring the magnetic field in the plasma of a quasi-spherical array, information is obtained on the processes of plasma production and formation of plasma flows from the wire/fiber regions with and without an additionally deposited mass. It is found that penetration of the magnetic flux depends on the initial linear mass profile m_l(θ) of the quasi-spherical array. From space-resolved spectral measurements and frame imaging of plasma X-ray emission, information is obtained on the dimensions and shape of the X-ray source formed during the implosion of a quasi-spherical array. The intensity of this source is estimated and compared with that of the Z-pinch formed during the implosion of a cylindrical array.

  4. The dispersion of age differences between partners and the asymptotic dynamics of the HIV epidemic.

    Science.gov (United States)

    d'Albis, Hippolyte; Augeraud-Véron, Emmanuelle; Djemai, Elodie; Ducrot, Arnaud

    2012-01-01

    In this paper, the effect of a change in the distribution of age differences between sexual partners on the dynamics of the HIV epidemic is studied. In a gender- and age-structured compartmental model, it is shown that if the variance of the distribution is small enough, an increase in this variance strongly increases the basic reproduction number. Moreover, if the variance is large enough, the mean age difference barely affects the basic reproduction number. We, therefore, conclude that the local stability of the disease-free equilibrium relies more on the variance than on the mean.

  5. A comparison of different measures for dynamical event mean transverse momentum fluctuation

    International Nuclear Information System (INIS)

    Liu Lianshou; Fu Jinghua

    2004-01-01

    Various measures for the dynamical event mean transverse momentum fluctuation are compared with the real dynamical fluctuation using a Monte Carlo model. The variance calculated from the G-moments can reproduce the dynamical variance well, while those obtained by subtraction procedures are approximate measures for not very low multiplicity. Φ pt , proposed by Gazdzicki M and Mrowczynski S, can also serve as an approximate measure after being divided by the square root of mean multiplicity

  6. Effect of temperament on milk production, somatic cell count, chemical composition and physical properties in Lacaune dairy sheep breed

    Directory of Open Access Journals (Sweden)

    Gábor Tóth

    2017-01-01

    Full Text Available Effect of temperament on milk yield, lactation length, physico-chemical properties and somatic cell count of Lacaune ewes were evaluated. The investigation was carried out at a sheep farm in the county of Győr-Moson-Sopron. The temperament of 106 Lacaune ewes was measured by the temperament 5-point-scale test (1=very nervous, 5=very quiet during milking. Furthermore, 42 ewes were randomly selected from a herd of 106 animals for the analysis of milk composition (fat, protein and lactose, pH, electrical conductivity as well as somatic cell count. It was found that the temperament had a significant effect on lactation length and lactation milk production, lactose, electrical conductivity and somatic cell count. Calm ewes had significantly longer lactation (4 score: 220.7 day; 5 score: 201.4 day as well as higher milk production (4 score: 207.9 kg; 5 score: 193.3 kg compared to more temperamental animals (2+3 scores: 166.5 day and 135.5 kg; P<0.05. The content of lactose was significantly lower (4.32 in the more temperamental group, while electrical conductivity was higher (4.81 mS cm-1 compared to calmer animals (4.69 % and 4.16 mS cm-1. Additionally, significant differences were found in milk somatic cell count among the temperament categories. Calmer ewes had a lower somatic cell count in milk (5.17 log cm-3 than more temperamental ones (5.67 log cm-3; P<0.05.

  7. Sex, Temperament, and Family Context: How the Interaction of Early Factors Differentially Predict Adolescent Alcohol Use and Are Mediated by Proximal Adolescent Factors

    Science.gov (United States)

    Burk, Linnea R.; Armstrong, Jeffrey M.; Goldsmith, H. Hill; Klein, Marjorie H.; Strauman, Timothy J.; Costanzo, Phillip; Essex, Marilyn J.

    2011-01-01

    Adolescent alcohol use is common and has serious immediate and long-term ramifications. While concurrent individual and context factors are robustly associated with adolescent alcohol use, the influence of early childhood factors, particularly in interaction with child sex, are less clear. Using a prospective community sample of 362 (190 girls), this study investigated sex differences in the joint influence of distal childhood and proximal adolescent factors on Grade 10 alcohol use. All risk factors and 2-way early individual-by-context interactions, and interactions of each of these with child sex, were entered into the initial regression. Significant sex interactions prompted the use of separate models for girls and boys. In addition to the identification of early (family socioeconomic status, authoritative parenting style) and proximal adolescent (mental health symptoms, deviant friends) risk factors for both girls and boys, results highlighted important sex differences. In particular, girls with higher alcohol consumption at Grade 10 were distinguished by the interaction of early temperamental disinhibition and exposure to parental stress; boys with higher alcohol consumption at Grade 10 were distinguished primarily by early temperamental negative affect. Results have implications for the timing and type of interventions offered to adolescents. PMID:21443307

  8. Sex, temperament, and family context: how the interaction of early factors differentially predict adolescent alcohol use and are mediated by proximal adolescent factors.

    Science.gov (United States)

    Burk, Linnea R; Armstrong, Jeffrey M; Goldsmith, H Hill; Klein, Marjorie H; Strauman, Timothy J; Costanzo, Phillip; Essex, Marilyn J

    2011-03-01

    Adolescent alcohol use is common and has serious immediate and long-term ramifications. While concurrent individual and context factors are robustly associated with adolescent alcohol use, the influence of early childhood factors, particularly in interaction with child sex, are less clear. Using a prospective community sample of 362 (190 girls), this study investigated sex differences in the joint influence of distal childhood and proximal adolescent factors on Grade 10 alcohol use. All risk factors and two-way early individual-by-context interactions, and interactions of each of these with child sex, were entered into the initial regression. Significant sex interactions prompted the use of separate models for girls and boys. In addition to the identification of early (family socioeconomic status, authoritative parenting style) and proximal adolescent (mental health symptoms, deviant friends) risk factors for both girls and boys, results highlighted important sex differences. In particular, girls with higher alcohol consumption at Grade 10 were distinguished by the interaction of early temperamental disinhibition and exposure to parental stress; boys with higher alcohol consumption at Grade 10 were distinguished primarily by early temperamental negative affect. Results have implications for the timing and type of interventions offered to adolescents.

  9. Seamount ecology and dynamics: A multidisciplinary data set from repeated surveys at different seamounts in the Northeast Atlantic and Mediterranean (2003 - 2013).

    Science.gov (United States)

    Mohn, C.; Christiansen, B.; Denda, A.; George, K. H.; Kaufmann, M.; Maranhão, M.; Martin, B.; Metzger, T.; Peine, F.; Schuster, A.; Springer, B.; Stefanowitsch, B.; Turnewitsch, R.; Wehrmann, H.

    2016-02-01

    Seamounts are amongst the most common physiographic open ocean systems, but remoteness and geographic complexity have limited the number of integrated and multidisciplinary seamount surveys in the past. As a consequence, important aspects of seamount ecology and dynamics remain poorly studied. Here we present a multi-parameter data set from individual and repeated seamount surveys conducted at different sites in the Northeast Atlantic and Eastern Mediterranean between 2003 and 2013. The main objective of these surveys was to establish a collection of ecosystem relevant descriptors and to develop a better understanding of seamount ecosystem composition and variability in different dynamical and bio-geographic environments. Measurements were conducted at four seamounts in the Northeast Atlantic (Ampère, Sedlo, Seine, Senghor) and two seamounts in the Eastern Mediterranean (Anaximenes, Eratosthenes). The data set comprises records from a total number of 11 cruises including physical oceanography (temperature, salinity, pressure, currents), biology (phytoplankton, zooplankton, fish, benthos) and biogeochemistry (sedimentary particle dynamics, carbon flux). The resulting multi-disciplinary data collection provides a unique opportunity for comparative studies of seamount ecosystem structure and dynamics between different physical, biological and biogeochemical regimes

  10. Combined cycle power plants: A comparison between two different dynamic models to evaluate transient behaviour and residual life

    International Nuclear Information System (INIS)

    Benato, Alberto; Stoppato, Anna; Bracco, Stefano

    2014-01-01

    Highlights: • Two procedures aimed at simulating the dynamic behaviour of power plants are compared. • They both are aimed at predicting the residual life of plant devices. • A single pressure gas-steam combined plant has been modelled. • A good correspondence has been found despite the different approaches used. - Abstract: The deregulated energy market and the increasing quota of electrical capacity covered by non-predictable renewable sources require strongly irregular and discontinuous operation of thermoelectric plants to satisfy users demand and compensate the variability of renewable sources. As a consequence, due to thermo-mechanical fatigue, creep and corrosion, a lifetime reduction of the most critical components occurs. The availability of a procedure able to predict the residual life of plant devices is necessary to assist the management decisions about power plants’ operation and maintenance scheduling. The first step of this procedure is the capability of simulating the plant behaviour versus time by evaluating the trends of the main thermodynamic parameters that describe the plant operation during different transient periods. In this context, the main contribution of the present paper is to propose a complete procedure able to simulate the plant dynamic behaviour and estimate the residual life reduction of some components. Indeed, two different models, developed by two different research groups, of the same single pressure heat recovery steam generator unit are presented and utilized to characterize the dynamic behaviour of the above mentioned power plant. The main thermodynamic variables during different transient operation conditions are predicted and good correspondence between the two methods is obtained. It can be also noted that, when the geometry and size of the devices are considered, the thermal inertia related to heat exchangers tubes, pipes and other physical masses causes a delay in the system response. Moreover, a residual life

  11. Special aspects of hemo-dynamic and reaction of erythrocytes in blood to standard physical load of different qualification female volleyball players

    Directory of Open Access Journals (Sweden)

    S. L. Popel’

    2017-10-01

    Full Text Available Purpose: to study the aspects of organism’s cardio-hemo-dynamic and blood erythrocytes reaction of female volleyball players to standard physical load. Material: with functional methods we studied cardio-hemo-dynamic and with the help of scanning electronic microscopy - erythrocytes’ structure in 18 female volleyball players of different qualification (age - 22.0±0.60 years. Results: it was found that maximal physical load causes substantial changes in cardio-hemo-dynamic, which depend on female volleyball players’ qualification. These changes have intrinsic to them type of blood circulation system reacting, which is manifested in the following: appropriate changes of some indicators; natural changes of periphery blood erythrocytes. In the article possible mechanisms of realization of female volleyball players’ organism’s typological features, depending on blood circulation type and erythrocytes’ conformation, are discussed. Conclusions: In relaxed state all female volleyball players have non-uniform cardio-hemo-dynamic of blood circulation. With hyper-dynamic blood circulation type, higher indicators of strike and minute blood volume were observed. With hypo-kinetic blood circulation type the opposite picture was observed: indicators of strike and minute blood volume, heart index, load on cardio-vascular system in different periods of day were low.

  12. Gender differences and dynamics shaping the adoption life cycle: review of the literature and recommendations.

    Science.gov (United States)

    Freeark, Kristine; Rosenberg, Elinor B; Bornstein, Jane; Jozefowicz-Simbeni, Debra; Linkevich, Michael; Lohnes, Kelly

    2005-01-01

    The role of gender in the experiences of adoptive family members has received little systematic attention. Gender differences in response to different tasks and phases of the adoption life cycle are described. Gendered dynamics within the adoptive family, for birth parents, and in the field of adoption are highlighted. Birth fathers and adoptive fathers are typically marginalized, which leaves women to address emotion, connection, and communication, and family dialogues about adoption may engage daughters more successfully than sons. The article reviews reasons why differential rates of problem behavior for adopted boys and girls may result from gender differences in emotional expressiveness, social support seeking, and identity formation. Implications of the feminization of adoption are explored, and recommendations for practice and research are proposed.

  13. An Investigation of dynamic characteristics of structures subjected to dynamic load from the viewpoint of design

    International Nuclear Information System (INIS)

    Lee, Hyun Ah; Kim, Yong Il; Park, Gyung Jin; Kang, Byung Soo; Kim, Joo Sung

    2006-01-01

    All the loads in the real world are dynamic loads and structural optimization under dynamic loads is very difficult. Thus the dynamic loads are often transformed to static loads by dynamic factors, which are believed equivalent to the dynamic loads. However, due to the difference of load characteristics, there can be considerable differences between the results from static and dynamic analyses. When the natural frequency of a structure is high, the dynamic analysis result is similar to that of static analysis due to the small inertia effect on the behavior of the structure. However, if the natural frequency of the structure is low, the inertia effect should not be ignored. then, the behavior of the dynamic system is different from that of the static system. The difference of the two cases can be explained from the relationship between the homogeneous and the particular solutions of the differential equation that governs the behavior of the structure. Through various examples, the difference between the dynamic analysis and the static analysis are shown. Also dynamic response optimization results are compared with the results with static loads transformed from dynamic loads by dynamic factors, which show the necessity of the design considering dynamic loads

  14. Complex dynamics of an eco-epidemiological model with different competition coefficients and weak Allee in the predator

    International Nuclear Information System (INIS)

    Saifuddin, Md.; Biswas, Santanu; Samanta, Sudip; Sarkar, Susmita; Chattopadhyay, Joydev

    2016-01-01

    The paper explores an eco-epidemiological model with weak Allee in predator, and the disease in the prey population. We consider a predator-prey model with type II functional response. The curiosity of this paper is to consider different competition coefficients within the prey population, which leads to the emergent carrying capacity. We perform the local and global stability analysis of the equilibrium points and the Hopf bifurcation analysis around the endemic equilibrium point. Further we pay attention to the chaotic dynamics which is produced by disease. Our numerical simulations reveal that the three species eco-epidemiological system without weak-Allee induced chaos from stable focus for increasing the force of infection, whereas in the presence of the weak-Allee effect, it exhibits stable solution. We conclude that chaotic dynamics can be controlled by the Allee parameter as well as the competition coefficients. We apply basic tools of non-linear dynamics such as Poincare section and maximum Lyapunov exponent to identify chaotic behavior of the system.

  15. Complexity and Dynamical Depth

    Directory of Open Access Journals (Sweden)

    Terrence Deacon

    2014-07-01

    Full Text Available We argue that a critical difference distinguishing machines from organisms and computers from brains is not complexity in a structural sense, but a difference in dynamical organization that is not well accounted for by current complexity measures. We propose a measure of the complexity of a system that is largely orthogonal to computational, information theoretic, or thermodynamic conceptions of structural complexity. What we call a system’s dynamical depth is a separate dimension of system complexity that measures the degree to which it exhibits discrete levels of nonlinear dynamical organization in which successive levels are distinguished by local entropy reduction and constraint generation. A system with greater dynamical depth than another consists of a greater number of such nested dynamical levels. Thus, a mechanical or linear thermodynamic system has less dynamical depth than an inorganic self-organized system, which has less dynamical depth than a living system. Including an assessment of dynamical depth can provide a more precise and systematic account of the fundamental difference between inorganic systems (low dynamical depth and living systems (high dynamical depth, irrespective of the number of their parts and the causal relations between them.

  16. Dynamics analysis of the fast-slow hydro-turbine governing system with different time-scale coupling

    Science.gov (United States)

    Zhang, Hao; Chen, Diyi; Wu, Changzhi; Wang, Xiangyu

    2018-01-01

    Multi-time scales modeling of hydro-turbine governing system is crucial in precise modeling of hydropower plant and provides support for the stability analysis of the system. Considering the inertia and response time of the hydraulic servo system, the hydro-turbine governing system is transformed into the fast-slow hydro-turbine governing system. The effects of the time-scale on the dynamical behavior of the system are analyzed and the fast-slow dynamical behaviors of the system are investigated with different time-scale. Furthermore, the theoretical analysis of the stable regions is presented. The influences of the time-scale on the stable region are analyzed by simulation. The simulation results prove the correctness of the theoretical analysis. More importantly, the methods and results of this paper provide a perspective to multi-time scales modeling of hydro-turbine governing system and contribute to the optimization analysis and control of the system.

  17. Temperament and parenting antecedents of individual differences in three-year-old boys' pride and shame reactions.

    Science.gov (United States)

    Belsky, J; Domitrovich, C; Crnic, K

    1997-06-01

    To examine individual differences in pride and shame reactions of 3-year-olds and their temperamental and parenting antecedents, 110 boys were studied at ages 36 and 37 months in a "rigged" achievement situation. After being trained to complete explicitly stipulated "easy" and "difficult" tasks before a buzzer sounded, success and failure were manipulated by artificially "rigging" how much time the child had to work on these tasks. Children's facial, verbal, and postural reactions to success and failure were composited to create pride scores following success and shame scores following failure. As expected, pride reactions were greater following success on the difficult than on the easy task, and shame reactions were greater following failure on the easy than on the difficult task. Early temperament (at 12/13 months) proved unrelated to pride and shame. With respect to parenting, measurements composited across 15, 21, 27, and 33 months showed that mothers and fathers who were more positive in their parenting had children who displayed less pride, and that children whose parents (especially mothers) were more negative in their parenting evinced less shame. These counterintuitive findings are discussed in terms of differences between assessments of parenting obtained in this investigation of parenting antecedents and those obtained in other studies of parental responses in the achievement situation itself. Directions for future research are outlined.

  18. Metapopulation dynamics of the mistletoe and its host in savanna areas with different fire occurrence.

    Directory of Open Access Journals (Sweden)

    Grazielle Sales Teodoro

    Full Text Available Mistletoes are aerial hemiparasitic plants which occupy patches of favorable habitat (host trees surrounded by unfavorable habitat and may be possibly modeled as a metapopulation. A metapopulation is defined as a subdivided population that persists due to the balance between colonization and extinction in discrete habitat patches. Our aim was to evaluate the dynamics of the mistletoe Psittacanthus robustus and its host Vochysia thyrsoidea in three Brazilian savanna areas using a metapopulation approach. We also evaluated how the differences in terms of fire occurrence affected the dynamic of those populations (two areas burned during the study and one was fire protected. We monitored the populations at six-month intervals. P. robustus population structure and dynamics met the expected criteria for a metapopulation: i the suitable habitats for the mistletoe occur in discrete patches; (ii local populations went extinct during the study and (iii colonization of previously non-occupied patches occurred. The ratio of occupied patches decreased in all areas with time. Local mistletoe populations went extinct due to two different causes: patch extinction in area with no fire and fire killing in the burned areas. In a burned area, the largest decrease of occupied patch ratios occurred due to a fire event that killed the parasites without, however, killing the host trees. The greatest mortality of V. thyrsoidea occurred in the area without fire. In this area, all the dead trees supported mistletoe individuals and no mortality was observed for parasite-free trees. Because P. robustus is a fire sensitive species and V. thyrsoidea is fire tolerant, P. robustus seems to increase host mortality, but its effect is lessened by periodic burning that reduces the parasite loads.

  19. Truly random dynamics generated by autonomous dynamical systems

    Science.gov (United States)

    González, J. A.; Reyes, L. I.

    2001-09-01

    We investigate explicit functions that can produce truly random numbers. We use the analytical properties of the explicit functions to show that a certain class of autonomous dynamical systems can generate random dynamics. This dynamics presents fundamental differences with the known chaotic systems. We present real physical systems that can produce this kind of random time-series. Some applications are discussed.

  20. Dynamic heterogeneity in life histories

    DEFF Research Database (Denmark)

    Tuljapurkar, Shripad; Steiner, Uli; Orzack, Steven Hecht

    2009-01-01

    or no fixed heterogeneity influences this trait. We propose that dynamic heterogeneity provides a 'neutral' model for assessing the possible role of unobserved 'quality' differences between individuals. We discuss fitness for dynamic life histories, and the implications of dynamic heterogeneity...... generate dynamic heterogeneity: life-history differences produced by stochastic stratum dynamics. We characterize dynamic heterogeneity in a range of species across taxa by properties of the Markov chain: the entropy, which describes the extent of heterogeneity, and the subdominant eigenvalue, which...... distributions of lifetime reproductive success. Dynamic heterogeneity contrasts with fixed heterogeneity: unobserved differences that generate variation between life histories. We show by an example that observed distributions of lifetime reproductive success are often consistent with the claim that little...

  1. Modelling Hermetic Compressors Using Different Constraint Equations to Accommodate Multibody Dynamics and Hydrodynamic Lubrication

    DEFF Research Database (Denmark)

    Estupinan, Edgar Alberto; Santos, Ilmar

    2009-01-01

    elements are supported by fluid film bearings, where the hydrodynamic interaction forces are described by the Reynolds equation. The system of nonlinear equations is numerically solved for three different restrictive conditions of the motion of the crank, where the third case takes into account lateral...... and tilting oscillations of the extremity of the crankshaft. The numerical results of the behaviour of the journal bearings for each case are presented giving some insights into design parameters such as, maximum oil film pressure, minimum oil film thickness, maximum vibration levels and dynamic reaction...

  2. Semiclassical dynamics

    International Nuclear Information System (INIS)

    Balazs, N.L.

    1979-01-01

    It is pointed out that in semiclassical dynamics one is encouraged to study the evolution of those curves in phase space which classically represent ensembles corresponding to wave functions. It is shown that the fixed points generate new time scales so that for times longer than the critical times, quantum dynamics will profoundly differ from classical dynamics. (P.L.)

  3. Power conditioning using dynamic voltage restorers under different voltage sag types.

    Science.gov (United States)

    Saeed, Ahmed M; Abdel Aleem, Shady H E; Ibrahim, Ahmed M; Balci, Murat E; El-Zahab, Essam E A

    2016-01-01

    Voltage sags can be symmetrical or unsymmetrical depending on the causes of the sag. At the present time, one of the most common procedures for mitigating voltage sags is by the use of dynamic voltage restorers (DVRs). By definition, a DVR is a controlled voltage source inserted between the network and a sensitive load through a booster transformer injecting voltage into the network in order to correct any disturbance affecting a sensitive load voltage. In this paper, modelling of DVR for voltage correction using MatLab software is presented. The performance of the device under different voltage sag types is described, where the voltage sag types are introduced using the different types of short-circuit faults included in the environment of the MatLab/Simulink package. The robustness of the proposed device is evaluated using the common voltage sag indices, while taking into account voltage and current unbalance percentages, where maintaining the total harmonic distortion percentage of the load voltage within a specified range is desired. Finally, several simulation results are shown in order to highlight that the DVR is capable of effective correction of the voltage sag while minimizing the grid voltage unbalance and distortion, regardless of the fault type.

  4. Dynamic analysis of the photoenhancement process of colloidal quantum dots with different surface modifications

    Energy Technology Data Exchange (ETDEWEB)

    Valledor Llopis, Marta; Campo Rodriguez, Juan Carlos; Ferrero Martin, Francisco J [Departamento de Ingenieria Electrica, Electronica, C y S Universidad de Oviedo, Campus de Gijon s/n, 33204 Gijon, Asturias, (Spain); Coto, Ana Maria; Fernandez-Argueelles, Maria T; Costa-Fernandez, J M; Sanz-Medel, A [Departamento de Quimica Fisica y Analitica, Universidad de Oviedo, Campus del Cristo, 33006 Oviedo, Asturias (Spain)

    2011-09-23

    Photoinduced fluorescence enhancement of colloidal quantum dots (QDs) is a hot topic addressed in many studies due to its great influence on the bioanalytical performance of such nanoparticles. However, understanding of this process is not a simple task, and it cannot be explained by a general mechanism as it greatly depends on the QDs' nature, solubilization strategies, surrounding environment, etc. In this vein, we have critically compared the behavior of CdSe QDs (widely used in bioanalytical applications) with different surface modifications (ligand exchange and polymer coating), in different controlled experimental conditions, in the presence-absence of the ZnS layer and in different media when exposed for long times to intense UV irradiation. Thus six different types of colloidal QDs were finally studied. This research was carried out from a novel perspective, based on the analysis of the dynamic behavior of the photoactivation process (of great interest for further applications of QDs as labels in biomedical applications). The results showed a different behavior of the studied colloidal QDs after UV irradiation in terms of their photoluminescence characteristics, potential toxicity due to metal release to the environment, nanoparticle stability and surface coating degradation.

  5. Dynamic analysis of the photoenhancement process of colloidal quantum dots with different surface modifications

    International Nuclear Information System (INIS)

    Valledor Llopis, Marta; Campo Rodriguez, Juan Carlos; Ferrero Martin, Francisco J; Coto, Ana Maria; Fernandez-Argueelles, Maria T; Costa-Fernandez, J M; Sanz-Medel, A

    2011-01-01

    Photoinduced fluorescence enhancement of colloidal quantum dots (QDs) is a hot topic addressed in many studies due to its great influence on the bioanalytical performance of such nanoparticles. However, understanding of this process is not a simple task, and it cannot be explained by a general mechanism as it greatly depends on the QDs' nature, solubilization strategies, surrounding environment, etc. In this vein, we have critically compared the behavior of CdSe QDs (widely used in bioanalytical applications) with different surface modifications (ligand exchange and polymer coating), in different controlled experimental conditions, in the presence-absence of the ZnS layer and in different media when exposed for long times to intense UV irradiation. Thus six different types of colloidal QDs were finally studied. This research was carried out from a novel perspective, based on the analysis of the dynamic behavior of the photoactivation process (of great interest for further applications of QDs as labels in biomedical applications). The results showed a different behavior of the studied colloidal QDs after UV irradiation in terms of their photoluminescence characteristics, potential toxicity due to metal release to the environment, nanoparticle stability and surface coating degradation.

  6. Measurement and inference of profile soil-water dynamics at different hillslope positions in a semiarid agricultural watershed

    Science.gov (United States)

    Green, Timothy R.; Erskine, Robert H.

    2011-12-01

    Dynamics of profile soil water vary with terrain, soil, and plant characteristics. The objectives addressed here are to quantify dynamic soil water content over a range of slope positions, infer soil profile water fluxes, and identify locations most likely influenced by multidimensional flow. The instrumented 56 ha watershed lies mostly within a dryland (rainfed) wheat field in semiarid eastern Colorado. Dielectric capacitance sensors were used to infer hourly soil water content for approximately 8 years (minus missing data) at 18 hillslope positions and four or more depths. Based on previous research and a new algorithm, sensor measurements (resonant frequency) were rescaled to estimate soil permittivity, then corrected for temperature effects on bulk electrical conductivity before inferring soil water content. Using a mass-conservation method, we analyzed multitemporal changes in soil water content at each sensor to infer the dynamics of water flux at different depths and landscape positions. At summit positions vertical processes appear to control profile soil water dynamics. At downslope positions infrequent overland flow and unsaturated subsurface lateral flow appear to influence soil water dynamics. Crop water use accounts for much of the variability in soil water between transects that are either cropped or fallow in alternating years, while soil hydraulic properties and near-surface hydrology affect soil water variability across landscape positions within each management zone. The observed spatiotemporal patterns exhibit the joint effects of short-term hydrology and long-term soil development. Quantitative methods of analyzing soil water patterns in space and time improve our understanding of dominant soil hydrological processes and provide alternative measures of model performance.

  7. Computational fluid dynamics modeling of bun baking process under different oven load conditions.

    Science.gov (United States)

    Tank, A; Chhanwal, N; Indrani, D; Anandharamakrishnan, C

    2014-09-01

    A computational fluid dynamics (CFD) model was developed to study the temperature profile of the bun during baking process. Evaporation-condensation mechanism and effect of the latent heat during phase change of water was incorporated in this model to represent actual bun baking process. Simulation results were validated with experimental measurements of bun temperature at two different positions. Baking process is completed within 20 min, after the temperature of crumb become stable at 98 °C. Further, this study was extended to investigate the effect of partially (two baking trays) loaded and fully loaded (eight baking trays) oven on temperature profile of bun. Velocity and temperature profile differs in partially loaded and fully loaded oven. Bun placed in top rack showed rapid baking while bun placed in bottom rack showed slower baking due to uneven temperature distribution in the oven. Hence, placement of bun inside the oven affects temperature of bun and consequently, the quality of the product.

  8. More than just noise: Inter-individual differences in fear acquisition, extinction and return of fear in humans - Biological, experiential, temperamental factors, and methodological pitfalls.

    Science.gov (United States)

    Lonsdorf, Tina B; Merz, Christian J

    2017-09-01

    Why do only some individuals develop pathological anxiety following adverse events? Fear acquisition, extinction and return of fear paradigms serve as experimental learning models for the development, treatment and relapse of anxiety. Individual differences in experimental performance were however mostly regarded as 'noise' by researchers interested in basic associative learning principles. Our work for the first time presents a comprehensive literature overview and methodological discussion on inter-individual differences in fear acquisition, extinction and return of fear. We tell a story from noise that steadily develops into a meaningful tune and converges to a model of mechanisms contributing to individual risk/resilience with respect to fear and anxiety-related behavior. Furthermore, in light of the present 'replicability crisis' we identify methodological pitfalls and provide suggestions for study design and analyses tailored to individual difference research in fear conditioning. Ultimately, synergistic transdisciplinary and collaborative efforts hold promise to not only improve our mechanistic understanding but can also be expected to contribute to the development of specifically tailored ('individualized') intervention and targeted prevention programs in the future. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Sleep duration partially accounts for race differences in diurnal cortisol dynamics.

    Science.gov (United States)

    Peterson, Laurel M; Miller, Karissa G; Wong, Patricia M; Anderson, Barbara P; Kamarck, Thomas W; Matthews, Karen A; Kirschbaum, Clemens; Manuck, Stephen B

    2017-05-01

    Emerging research demonstrates race differences in diurnal cortisol slope, an indicator of hypothalamic-pituitary-adrenocortical (HPA)-axis functioning associated with morbidity and mortality, with African Americans showing flatter diurnal slopes than their White counterparts. Sleep characteristics are associated with both race and with HPA-axis functioning. The present report examines whether sleep duration may account for race differences in cortisol dynamics. Participants were 424 employed African American and White adults (mean age = 42.8 years, 84.2% White, 53.6% female) with no cardiovascular disease (Adult Health and Behavior Project-Phase 2 [AHAB-II] cohort, University of Pittsburgh). Cortisol slope was calculated using 4 salivary cortisol readings, averaged over each of 4 days. Demographic (age, sex), psychosocial (socioeconomic status [SES], affect, discrimination), and health behaviors (smoking, alcohol use, physical activity) variables were used as covariates, and sleep (self-report and accelerometry) was also assessed. African Americans had flatter slopes than Whites (F(1, 411) = 10.45, B = .02, p = .001) in models adjusting for demographic, psychosocial, and health behavior covariates. Shorter actigraphy-assessed total sleep time was a second significant predictor of flatter cortisol slopes (F(1, 411) = 25.27, B = -.0002, p race and diurnal slope [confidence interval = .05 (lower = .014, upper .04)]. African Americans have flatter diurnal cortisol slopes than their White counterparts, an effect that may be partially attributable to race differences in nightly sleep duration. Sleep parameters should be considered in further research on race and cortisol. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  10. Analysis of the dynamics of Rhizomucor miehei lipase at different temperatures

    DEFF Research Database (Denmark)

    Peters, Günther H.j.; Toxvaerd, S.; Andersen, K.V.

    1999-01-01

    The dynamics of Rhizomucor miehei lipase has been studied by molecular dynamics simulations at temperatures ranging from 200-500K. Simulations carried out in periodic boundary conditions and using explicit water molecules were performed for 400 ps at each temperature. Our results indicate...... that conformational changes and internal motions in the protein are significantly influenced by the temperature increase. With increasing temperature, the number of internal hydrogen bonds decreases, while surface accessibility, radius of gyration and the number of residues in random coil conformation increase...

  11. Dynamical principles in neuroscience

    International Nuclear Information System (INIS)

    Rabinovich, Mikhail I.; Varona, Pablo; Selverston, Allen I.; Abarbanel, Henry D. I.

    2006-01-01

    Dynamical modeling of neural systems and brain functions has a history of success over the last half century. This includes, for example, the explanation and prediction of some features of neural rhythmic behaviors. Many interesting dynamical models of learning and memory based on physiological experiments have been suggested over the last two decades. Dynamical models even of consciousness now exist. Usually these models and results are based on traditional approaches and paradigms of nonlinear dynamics including dynamical chaos. Neural systems are, however, an unusual subject for nonlinear dynamics for several reasons: (i) Even the simplest neural network, with only a few neurons and synaptic connections, has an enormous number of variables and control parameters. These make neural systems adaptive and flexible, and are critical to their biological function. (ii) In contrast to traditional physical systems described by well-known basic principles, first principles governing the dynamics of neural systems are unknown. (iii) Many different neural systems exhibit similar dynamics despite having different architectures and different levels of complexity. (iv) The network architecture and connection strengths are usually not known in detail and therefore the dynamical analysis must, in some sense, be probabilistic. (v) Since nervous systems are able to organize behavior based on sensory inputs, the dynamical modeling of these systems has to explain the transformation of temporal information into combinatorial or combinatorial-temporal codes, and vice versa, for memory and recognition. In this review these problems are discussed in the context of addressing the stimulating questions: What can neuroscience learn from nonlinear dynamics, and what can nonlinear dynamics learn from neuroscience?

  12. Dynamical principles in neuroscience

    Science.gov (United States)

    Rabinovich, Mikhail I.; Varona, Pablo; Selverston, Allen I.; Abarbanel, Henry D. I.

    2006-10-01

    Dynamical modeling of neural systems and brain functions has a history of success over the last half century. This includes, for example, the explanation and prediction of some features of neural rhythmic behaviors. Many interesting dynamical models of learning and memory based on physiological experiments have been suggested over the last two decades. Dynamical models even of consciousness now exist. Usually these models and results are based on traditional approaches and paradigms of nonlinear dynamics including dynamical chaos. Neural systems are, however, an unusual subject for nonlinear dynamics for several reasons: (i) Even the simplest neural network, with only a few neurons and synaptic connections, has an enormous number of variables and control parameters. These make neural systems adaptive and flexible, and are critical to their biological function. (ii) In contrast to traditional physical systems described by well-known basic principles, first principles governing the dynamics of neural systems are unknown. (iii) Many different neural systems exhibit similar dynamics despite having different architectures and different levels of complexity. (iv) The network architecture and connection strengths are usually not known in detail and therefore the dynamical analysis must, in some sense, be probabilistic. (v) Since nervous systems are able to organize behavior based on sensory inputs, the dynamical modeling of these systems has to explain the transformation of temporal information into combinatorial or combinatorial-temporal codes, and vice versa, for memory and recognition. In this review these problems are discussed in the context of addressing the stimulating questions: What can neuroscience learn from nonlinear dynamics, and what can nonlinear dynamics learn from neuroscience?

  13. Dynamic critical behaviour and scaling

    International Nuclear Information System (INIS)

    Oezoguz, B.E.

    2001-01-01

    Traditionally the scaling is the property of dynamical systems at thermal equilibrium. In second order phase transitions scaling behaviour is due to the infinite correlation length around the critical point. In first order phase transitions however, the correlation length remains finite and a different type of scaling can be observed. For first order phase transitions all singularities are governed by the volume of the system. Recently, a different type of scaling, namely dynamic scaling has attracted attention in second order phase transitions. In dynamic scaling, when a system prepared at high temperature is quenched to the critical temperature, it exhibits scaling behaviour. Dynamic scaling has been applied to various spin systems and the validity of the arguments are shown. Firstly, in this thesis project the dynamic scaling is applied to 4-dimensional using spin system which exhibits second order phase transition with mean-field critical indices. Secondly, it is shown that although the dynamic is quite different, first order phase transitions also has a different type of dynamic scaling

  14. Charge carrier dynamics in PMMA-LiClO4 based polymer electrolytes plasticized with different plasticizers

    Science.gov (United States)

    Pal, P.; Ghosh, A.

    2017-07-01

    We have studied the charge carrier dynamics in poly(methylmethacrylate)-LiClO4 polymer electrolytes plasticized with different plasticizers such as ethylene carbonate (EC), propylene carbonate (PC), polyethylene glycol (PEG), and dimethyl carbonate (DMC). We have measured the broadband complex conductivity spectra of these electrolytes in the frequency range of 0.01 Hz-3 GHz and in the temperature range of 203 K-363 K and analyzed the conductivity spectra in the framework of the random barrier model by taking into account the contribution of the electrode polarization observed at low frequencies and/or at high temperatures. It is observed that the temperature dependences of the ionic conductivity and relaxation time follow the Vogel-Tammann-Fulcher relation for all plasticized electrolytes. We have also performed the scaling of the conductivity spectra, which indicates that the charge carrier dynamics is almost independent of temperature and plasticizers in a limited frequency range. The existence of nearly constant loss in these electrolytes has been observed at low temperatures and/or high frequencies. We have studied the dielectric relaxation in these electrolytes using electric modulus formalism and obtained the stretched exponent and the decay function. We have observed less cooperative ion dynamics in electrolytes plasticized with DMC compared to electrolytes plasticized with EC, PC, and PEG.

  15. Dynamic covalent gels assembled from small molecules:from discrete gelators to dynamic covalent polymers

    Institute of Scientific and Technical Information of China (English)

    Jian-Yong Zhang; Li-Hua Zeng; Juan Feng

    2017-01-01

    Dynamic covalent chemistry has emerged recently to be a powerful tool to construct functional materials.This article reviews the progress in the research and development of dynamic covalent chemistry in gels assembled from small molecules.First dynamic covalent reactions used in gels are reviewed to understand the dynamic covalent bonding.Afterwards the catalogues of dynamic covalent gels are reviewed according to the nature of gelators and the interactions between gelators.Dynamic covalent bonding can be involved to form low molecular weight gelators.Low molecular weight molecules with multiple functional groups react to form dynamic covalent cross-linked polymers and act as gelators.Two catalogues of gels show different properties arising from their different structures.This review aims to illustrate the structure-property relationships of these dynamic covalent gels.

  16. [Computational fluid dynamics simulation of different impeller combinations in high viscosity fermentation and its application].

    Science.gov (United States)

    Dong, Shuhao; Zhu, Ping; Xu, Xiaoying; Li, Sha; Jiang, Yongxiang; Xu, Hong

    2015-07-01

    Agitator is one of the essential factors to realize high efficient fermentation for high aerobic and viscous microorganisms, and the influence of different impeller combination on the fermentation process is very important. Welan gum is a microbial exopolysaccharide produced by Alcaligenes sp. under high aerobic and high viscos conditions. Computational fluid dynamics (CFD) numerical simulation was used for analyzing the distribution of velocity, shear rate and gas holdup in the welan fermentation reactor under six different impeller combinations. The best three combinations of impellers were applied to the fermentation of welan. By analyzing the fermentation performance, the MB-4-6 combination had better effect on dissolved oxygen and velocity. The content of welan was increased by 13%. Furthermore, the viscosity of production were also increased.

  17. Assessment of three different software systems in the evaluation of dynamic MRI of the breast

    International Nuclear Information System (INIS)

    Kurz, K.D.; Steinhaus, D.; Klar, V.; Cohnen, M.; Wittsack, H.J.; Saleh, A.; Moedder, U.; Blondin, D.

    2009-01-01

    Objective: The aim was to compare the diagnostic performance and handling of dynamic contrast-enhanced MRI of the breast with two commercial software solutions ('CADstream' and '3TP') and one self-developed software system ('Mammatool'). Materials and methods: Identical data sets of dynamic breast MRI from 21 patients were evaluated retrospectively with all three software systems. The exams were classified according to the BI-RADS classification. The number of lesions in the parametric mapping was compared to histology or follow-up of more than 2 years. In addition, 25 quality criteria were judged by 3 independent investigators with a score from 0 to 5. Statistical analysis was performed to document the quality ranking of the different software systems. Results: There were 9 invasive carcinomas, one pure DCIS, one papilloma, one radial scar, three histologically proven changes due to mastopathy, one adenosis and two fibroadenomas. Additionally two patients with enhancing parenchyma followed with MRI for more than 3 years and one scar after breast conserving therapy were included. All malignant lesions were classified as BI-RADS 4 or 5 using all software systems and showed significant enhancement in the parametric mapping. 'CADstream' showed the best score on subjective quality criteria. '3TP' showed the lowest number of false-positive results. 'Mammatool' produced the lowest number of benign tissues indicated with parametric overlay. Conclusion: All three software programs tested were adequate for sensitive and efficient assessment of dynamic MRI of the breast. Improvements in specificity may be achievable

  18. Assessment of three different software systems in the evaluation of dynamic MRI of the breast.

    Science.gov (United States)

    Kurz, K D; Steinhaus, D; Klar, V; Cohnen, M; Wittsack, H J; Saleh, A; Mödder, U; Blondin, D

    2009-02-01

    The aim was to compare the diagnostic performance and handling of dynamic contrast-enhanced MRI of the breast with two commercial software solutions ("CADstream" and "3TP") and one self-developed software system ("Mammatool"). Identical data sets of dynamic breast MRI from 21 patients were evaluated retrospectively with all three software systems. The exams were classified according to the BI-RADS classification. The number of lesions in the parametric mapping was compared to histology or follow-up of more than 2 years. In addition, 25 quality criteria were judged by 3 independent investigators with a score from 0 to 5. Statistical analysis was performed to document the quality ranking of the different software systems. There were 9 invasive carcinomas, one pure DCIS, one papilloma, one radial scar, three histologically proven changes due to mastopathy, one adenosis and two fibroadenomas. Additionally two patients with enhancing parenchyma followed with MRI for more than 3 years and one scar after breast conserving therapy were included. All malignant lesions were classified as BI-RADS 4 or 5 using all software systems and showed significant enhancement in the parametric mapping. "CADstream" showed the best score on subjective quality criteria. "3TP" showed the lowest number of false-positive results. "Mammatool" produced the lowest number of benign tissues indicated with parametric overlay. All three software programs tested were adequate for sensitive and efficient assessment of dynamic MRI of the breast. Improvements in specificity may be achievable.

  19. INTENSITY OF THE DYNAMICS OF PHYSICAL PREPAREDNESS IN THE PROCESS OF STUDENTS GROWING UP WITH DIFFERENT LEVELS OF INTELLIGENCE

    Directory of Open Access Journals (Sweden)

    E. M. Revenko

    2016-01-01

    Full Text Available The purpose of the investigation is the scientific substantiation forthe implementation of a differentiated approach to the organization of physical education on the basis of accounting students individually-typological features of the age.Methods. Motor abilities of students are studied by measuring: force (backbone dynamometry, strength endurance (pulling up on the bar, speed-strength abilities (long jump from their seats, as well as high-speed capacity (running at 30, 60 or 100 meters, depending on the age, aerobic endurance (running at 1000 or 3000 m, depending on age. The dynamics of the integrated physical preparedness (DIPP of each student is estimated by calculating the arithmetic mean value of the growth rate of the development of motor abilities listed above (the results of 5 tests. Evaluation of general intelligence (GI of schoolchildren in 8, 10 and 11 classes, students of 1 – 3 courses carried out by the test of R. Amthauer adapted by L. A. Yasyukova [13], and the 6 classes pupils – through the intellectual test (GIT [1].Results. It was experimentally established that students of 6, 8, 10, 11 grades and 1 – 3 courses at higher intelligence level have a low dynamics of physical fitness. On the contrary, students with a lower level of intelligence revealed a high dynamics of physical fitness. Marked discrepancies in the dynamics of the development of mental and motor areas of maturing personality are interpreted as individual-typological features of age-related development. Based on these facts it is concluded that the organization of physical education on the basis of program-regulatory approach with common unified requirements involved, will not allow to create conditions for highquality physical education of the younger generation and the formation of a sustainable motivation for self-employment by physical exercises.Scientific novelty. Scientific evidence of sustained differences in the dynamics of the

  20. Autobiographical memories of childhood and sources of subjectivity in parents' perceptions of infant temperament.

    Science.gov (United States)

    Manczak, Erika M; Mangelsdorf, Sarah C; McAdams, Dan P; Wong, Maria S; Schoppe-Sullivan, Sarah; Brown, Geoffrey L

    2016-08-01

    The current study examined whether autobiographical memories from parents' own childhoods, prebirth expectations, and personality traits contributed to their perceptions of their infants' temperament. It also investigated whether mothers and fathers differed in the extent to which these three sources of subjectivity predicted their perceptions. During the third trimester of pregnancy, expectant mothers and fathers in 96 families completed assessments of their personality traits and expectations for their children's temperament, as well as provided characteristic memories of their relationships with their own caregivers as children. Memories were then coded for themes of growth versus safety and compared to parents' ratings of perceived child temperament 15 months later. Analyses revealed that, for both parents, prebirth expectations predicted perceptions of positive temperament behaviors. Moreover, fathers who described childhoods characterized by exploration and opportunities for growth also perceived their children as displaying more positive temperamental behaviors, whereas those who described greater safety focus in memories and who had higher levels of negative affectivity reported more negative temperamental behaviors. These findings suggest that mothers' and fathers' perceptions of their children are differently related to psychological variables, including autobiographical memories. In turn, it is possible that these subjective perceptions may affect the parenting environment. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Comparing the difference of measured GFR of ectopic pelvic kidney between anterior and posterior imaging processing in renal dynamic imaging

    International Nuclear Information System (INIS)

    Li Baojun; Zhao Deshan

    2014-01-01

    Objective: To compare and analyze the difference of measured glomerular filtration rate (GFR) of ectopic pelvic kidney between anterior and posterior imaging processing in renal dynamic imaging. Methods: There were 10 patients collected retrospectively, with ectopic kidneys in pelvic cavity confirmed by ultrasound, CT, renal dynamic imaging and other imaging modalities. All images of ectopic kidneys in renal dynamic imaging were processed by anterior and posterior methods respectively. The ectopic kidney was only processed in anterior imaging, ectopic kidney and contralateral normal kidney were processed in posterior imaging. Total GFR equalled the sum of GFR of normal kidney in posterior imaging and GFR of ectopic kidney in anterior imaging, was compared with total GFR of two kidneys in posterior imaging and GFR in two-sample method. All correlation analysis were completed between GFRs from three methods and all patients were followed up. Statistically paired t-test and bivariate correlation analysis test were used. Results: The mean GFR of ectopic kidney in anterior imaging equal to (27.48±12.24) ml/(min · 1.73 m 2 ). It was more than GFR [(10.71 ±4.74) ml/ (min · 1.73 m 2 )] in posterior imaging above 46% (t=5.481, P<0.01). There was no significant difference (t=-2.238, P>0.05), but better correlation (r=0.704, P<0.05) between total GFR in anterior imaging and GFR in two-sample method. There was significant difference (t=4.629, P<0.01)and worse correlation (r=0.576, P>0.05) between total GFR in posterior imaging and GFR in two-sample method. Conclusion: Comparing with GFR in posterior imaging, GFR in anterior imaging can more truly reflect function condition of ectopic pelvic kidney in renal dynamic imaging. (authors)

  2. Modeling 3D Dynamic Rupture on Arbitrarily-Shaped faults by Boundary-Conforming Finite Difference Method

    Science.gov (United States)

    Zhu, D.; Zhu, H.; Luo, Y.; Chen, X.

    2008-12-01

    We use a new finite difference method (FDM) and the slip-weakening law to model the rupture dynamics of a non-planar fault embedded in a 3-D elastic media with free surface. The new FDM, based on boundary- conforming grid, sets up the mapping equations between the curvilinear coordinate and the Cartesian coordinate and transforms irregular physical space to regular computational space; it also employs a higher- order non-staggered DRP/opt MacCormack scheme which is of low dispersion and low dissipation so that the high accuracy and stability of our rupture modeling are guaranteed. Compared with the previous methods, not only we can compute the spontaneous rupture of an arbitrarily shaped fault, but also can model the influence of the surface topography on the rupture process of earthquake. In order to verify the feasibility of this method, we compared our results and other previous results, and found out they matched perfectly. Thanks to the boundary-conforming FDM, problems such as dynamic rupture with arbitrary dip, strike and rake over an arbitrary curved plane can be handled; and supershear or subshear rupture can be simulated with different parameters such as the initial stresses and the critical slip displacement Dc. Besides, our rupture modeling is economical to be implemented owing to its high efficiency and does not suffer from displacement leakage. With the help of inversion data of rupture by field observations, this method is convenient to model rupture processes and seismograms of natural earthquakes.

  3. Vortex Dynamics in Superconductors with Different Types of Pinning Potentials; Dinamica de Vortices en Superconductores con Diferentes tipos de Anclaje

    Energy Technology Data Exchange (ETDEWEB)

    Laguna, Maria Fabiana [Comision Nacional de Energia Atomica, Centro Atomico Bariloche, San Carlos de Bariloche (Argentina)

    2001-07-01

    In this work we study the behavior of the vortex system in the mixed state of a type II superconductor when it interacts with different kinds of pinning potentials. To do this, we perform numerical simulations in the presence of an external magnetic field, by making use of two different approaches.One corresponds to a Langevin simulation of the three dimensional XY model or Josephson-junction network, whereas the other corresponds to a Molecular dynamics simulation of two dimensional point-like vortices.We analyze the transport properties of highly anisotropic superconductors with different kinds of topological disorder in the configuration in which the external field is applied perpendicular to the CuO planes.We found that for systems with point defects the activation energy is the same for the two components of the resistivity, while in systems with columnar defects the activation energies can be different.We also study the structure, phase transitions and transport properties of the vortex system when the external magnetic field lies parallel to the planes in layered superconductors. We analyze the stability of different phases at low temperatures and show under which conditions the smectic phase is stable.Our results indicate the presence of the smectic phase in an intermediate range of temperatures.We have studied a vortex array in a periodic pinning potential with triangular and kagome geometries.We obtain the ground state vortex configurations and calculate some thermodynamic quantities for different magnetic fields.We observe several stages of lattice pinning and melting and we characterize different phases and transitions between them.Finally, simulating the Bitter pinning effect over the vortex system, we study static and dynamic properties of the vortex system in the presence of the surface Bitter pinning and the bulk pinning.We found low temperature structures similar to those obtained experimentally.We analyze the dynamics of the nucleation and growth

  4. Differences in dynamic autoregulation of renal blood flow between SHR and WKY rats

    DEFF Research Database (Denmark)

    Chen, Y M; Holstein-Rathlou, N H

    1993-01-01

    by chaotic fluctuations. We sought to determine whether this change was associated with a change in the dynamic autoregulation of renal blood flow. In halothane-anesthetized 250- to 320-g SHR and WKY rats, renal blood flow was measured during "white noise" forcing of arterial blood pressure. The frequency...... conclude that the change in the dynamics of TGF leads to a change in the dynamic autoregulation of renal blood flow between SHR and WKY rats. This change results in a more efficient dynamic autoregulation of renal blood flow in the SHR compared with the WKY rats. The functional consequences of this......In halothane-anesthetized Wistar-Kyoto (WKY) rats the single-nephron blood flow and the proximal tubule pressure oscillate at a frequency of 35-50 mHz because of the operation of the tubuloglomerular feedback (TGF) mechanism. In spontaneously hypertensive rats (SHR) the oscillations are replaced...

  5. Skin Sensitive Difference of Human Body Sections under Clothing-Smirnov Test of Skin Surface Temperatures' Dynamic Changing

    Institute of Scientific and Technical Information of China (English)

    LI Jun; WU Hai-yan; WANG Yun-yi

    2004-01-01

    Skin sensitive difference of human body sections under clothing is the theoretic foundation of thermal insulation clothing design.By a new method of researching on clothing comfort perception,the skin temperature live changing procedure of human body sections affected by the same cold stimulation is inspected.Furthermore with the Smirnov test the skin temperatures dynamic changing patterns of main human body sections are obtained.

  6. Application of time series analysis on molecular dynamics simulations of proteins: a study of different conformational spaces by principal component analysis.

    Science.gov (United States)

    Alakent, Burak; Doruker, Pemra; Camurdan, Mehmet C

    2004-09-08

    Time series analysis is applied on the collective coordinates obtained from principal component analysis of independent molecular dynamics simulations of alpha-amylase inhibitor tendamistat and immunity protein of colicin E7 based on the Calpha coordinates history. Even though the principal component directions obtained for each run are considerably different, the dynamics information obtained from these runs are surprisingly similar in terms of time series models and parameters. There are two main differences in the dynamics of the two proteins: the higher density of low frequencies and the larger step sizes for the interminima motions of colicin E7 than those of alpha-amylase inhibitor, which may be attributed to the higher number of residues of colicin E7 and/or the structural differences of the two proteins. The cumulative density function of the low frequencies in each run conforms to the expectations from the normal mode analysis. When different runs of alpha-amylase inhibitor are projected on the same set of eigenvectors, it is found that principal components obtained from a certain conformational region of a protein has a moderate explanation power in other conformational regions and the local minima are similar to a certain extent, while the height of the energy barriers in between the minima significantly change. As a final remark, time series analysis tools are further exploited in this study with the motive of explaining the equilibrium fluctuations of proteins. Copyright 2004 American Institute of Physics

  7. Simulation of computational fluid dynamics and comparison of cephalosporin C fermentation performance with different impeller combinations

    Energy Technology Data Exchange (ETDEWEB)

    Duan, Shengbing; Ni, Weijia; Luo, Hongzhen; Shi, Zhongping; Liu, Fan [Jiangnan University, Wuxi (China); Yuan, Guoqiang; Zhao, Yanli [CSPC Hebei Zhongrun Pharmaceutical Co. Ltd., Shijiazhuang (China)

    2013-05-15

    Cephalosporin C (CPC) fermentation by Acremonium chrysogenum is an extremely high oxygen-consuming process and oxygen transfer rate in a bioreactor directly affects fermentation performance. In this study, fluid dynamics and oxygen transfer in a 7 L bioreactor with different impellers combinations were simulated by computational fluid dynamics (CFD) model. Based on the simulation results, two impeller combinations with higher oxygen transfer rate (K{sub L}a) were selected to conduct CPC fermentations, aiming at achieving high CPC concentration and low accumulation of major by-product, deacetoxycephalosporin (DAOC). It was found that an impeller combination with a higher K{sub L}a and moderate shear force is the prerequisite for efficient CPC production in a stirred bioreactor. The best impeller combination, which installed a six-bladed turbine and a four-pitched-blade turbine at bottom and upper layers but with a shortened impellers inter-distance, produced the highest CPC concentration of 35.77 g/L and lowest DAOC/CPC ratio of 0.5%.

  8. Simulation of computational fluid dynamics and comparison of cephalosporin C fermentation performance with different impeller combinations

    International Nuclear Information System (INIS)

    Duan, Shengbing; Ni, Weijia; Luo, Hongzhen; Shi, Zhongping; Liu, Fan; Yuan, Guoqiang; Zhao, Yanli

    2013-01-01

    Cephalosporin C (CPC) fermentation by Acremonium chrysogenum is an extremely high oxygen-consuming process and oxygen transfer rate in a bioreactor directly affects fermentation performance. In this study, fluid dynamics and oxygen transfer in a 7 L bioreactor with different impellers combinations were simulated by computational fluid dynamics (CFD) model. Based on the simulation results, two impeller combinations with higher oxygen transfer rate (K_La) were selected to conduct CPC fermentations, aiming at achieving high CPC concentration and low accumulation of major by-product, deacetoxycephalosporin (DAOC). It was found that an impeller combination with a higher K_La and moderate shear force is the prerequisite for efficient CPC production in a stirred bioreactor. The best impeller combination, which installed a six-bladed turbine and a four-pitched-blade turbine at bottom and upper layers but with a shortened impellers inter-distance, produced the highest CPC concentration of 35.77 g/L and lowest DAOC/CPC ratio of 0.5%

  9. Recursive Estimation for Dynamical Systems with Different Delay Rates Sensor Network and Autocorrelated Process Noises

    Directory of Open Access Journals (Sweden)

    Jianxin Feng

    2014-01-01

    Full Text Available The recursive estimation problem is studied for a class of uncertain dynamical systems with different delay rates sensor network and autocorrelated process noises. The process noises are assumed to be autocorrelated across time and the autocorrelation property is described by the covariances between different time instants. The system model under consideration is subject to multiplicative noises or stochastic uncertainties. The sensor delay phenomenon occurs in a random way and each sensor in the sensor network has an individual delay rate which is characterized by a binary switching sequence obeying a conditional probability distribution. By using the orthogonal projection theorem and an innovation analysis approach, the desired recursive robust estimators including recursive robust filter, predictor, and smoother are obtained. Simulation results are provided to demonstrate the effectiveness of the proposed approaches.

  10. Dynamics based alignment of proteins: an alternative approach to quantify dynamic similarity

    Directory of Open Access Journals (Sweden)

    Lyngsø Rune

    2010-04-01

    Full Text Available Abstract Background The dynamic motions of many proteins are central to their function. It therefore follows that the dynamic requirements of a protein are evolutionary constrained. In order to assess and quantify this, one needs to compare the dynamic motions of different proteins. Comparing the dynamics of distinct proteins may also provide insight into how protein motions are modified by variations in sequence and, consequently, by structure. The optimal way of comparing complex molecular motions is, however, far from trivial. The majority of comparative molecular dynamics studies performed to date relied upon prior sequence or structural alignment to define which residues were equivalent in 3-dimensional space. Results Here we discuss an alternative methodology for comparative molecular dynamics that does not require any prior alignment information. We show it is possible to align proteins based solely on their dynamics and that we can use these dynamics-based alignments to quantify the dynamic similarity of proteins. Our method was tested on 10 representative members of the PDZ domain family. Conclusions As a result of creating pair-wise dynamics-based alignments of PDZ domains, we have found evolutionarily conserved patterns in their backbone dynamics. The dynamic similarity of PDZ domains is highly correlated with their structural similarity as calculated with Dali. However, significant differences in their dynamics can be detected indicating that sequence has a more refined role to play in protein dynamics than just dictating the overall fold. We suggest that the method should be generally applicable.

  11. Comparison of three different scales techniques for the dynamic mechanical characterization of two polymers (PDMS and SU8)

    Science.gov (United States)

    Le Rouzic, J.; Delobelle, P.; Vairac, P.; Cretin, B.

    2009-10-01

    In this article the dynamic mechanical characterization of PDMS and SU8 resin using dynamic mechanical analysis, nanoindentation and the scanning microdeformation microscope have been presented. The methods are hereby explained, extended for viscoelastic behaviours, and their compatibility underlined. The storage and loss moduli of these polymers over a wide range of frequencies (from 0.01 Hz to somekHz) have been measured. These techniques are shown fairly matching and the two different viscoelastic behaviours of these two polymers have been exhibited. Indeed, PDMS shows moduli which still increase at 5kHz whereas SU8 ones decrease much sooner. From a material point of view, the Havriliak and Negami model to estimate instantaneous, relaxed moduli and time constant of these materials has been identified.

  12. Assessment of three different software systems in the evaluation of dynamic MRI of the breast

    Energy Technology Data Exchange (ETDEWEB)

    Kurz, K.D. [Department of Radiology, Stavanger University Hospital, Postbox 8100, Stavanger (Norway)], E-mail: kurk@sus.no; Steinhaus, D. [Institute of Daignostic Radiology, Duesseldorf University Hospital, Moorenstr. 5, 40225 Duesseldorf (Germany)], E-mail: Daniele.Steinhaus@med.uni-duesseldorf.de; Klar, V. [Institute of Daignostic Radiology, Duesseldorf University Hospital, Moorenstr. 5, 40225 Duesseldorf (Germany)], E-mail: verena.klar@uni-duesseldorf.de; Cohnen, M. [Institute of Daignostic Radiology, Duesseldorf University Hospital, Moorenstr. 5, 40225 Duesseldorf (Germany)], E-mail: cohnen@med.uni-duesseldorf.de; Wittsack, H.J. [Institute of Daignostic Radiology, Duesseldorf University Hospital, Moorenstr. 5, 40225 Duesseldorf (Germany)], E-mail: wittsack@uni-duesseldorf.de; Saleh, A. [Institute of Daignostic Radiology, Duesseldorf University Hospital, Moorenstr. 5, 40225 Duesseldorf (Germany)], E-mail: saleh@uni-duesseldorf.de; Moedder, U. [Institute of Daignostic Radiology, Duesseldorf University Hospital, Moorenstr. 5, 40225 Duesseldorf (Germany)], E-mail: moedder@med.uni-duesseldorf.de; Blondin, D. [Institute of Daignostic Radiology, Duesseldorf University Hospital, Moorenstr. 5, 40225 Duesseldorf (Germany)], E-mail: blondin@med.uni-duesseldorf.de

    2009-02-15

    Objective: The aim was to compare the diagnostic performance and handling of dynamic contrast-enhanced MRI of the breast with two commercial software solutions ('CADstream' and '3TP') and one self-developed software system ('Mammatool'). Materials and methods: Identical data sets of dynamic breast MRI from 21 patients were evaluated retrospectively with all three software systems. The exams were classified according to the BI-RADS classification. The number of lesions in the parametric mapping was compared to histology or follow-up of more than 2 years. In addition, 25 quality criteria were judged by 3 independent investigators with a score from 0 to 5. Statistical analysis was performed to document the quality ranking of the different software systems. Results: There were 9 invasive carcinomas, one pure DCIS, one papilloma, one radial scar, three histologically proven changes due to mastopathy, one adenosis and two fibroadenomas. Additionally two patients with enhancing parenchyma followed with MRI for more than 3 years and one scar after breast conserving therapy were included. All malignant lesions were classified as BI-RADS 4 or 5 using all software systems and showed significant enhancement in the parametric mapping. 'CADstream' showed the best score on subjective quality criteria. '3TP' showed the lowest number of false-positive results. 'Mammatool' produced the lowest number of benign tissues indicated with parametric overlay. Conclusion: All three software programs tested were adequate for sensitive and efficient assessment of dynamic MRI of the breast. Improvements in specificity may be achievable.

  13. Comparison of three different concepts of high dynamic range and dependability optimised current measurement digitisers for beam loss systems

    CERN Document Server

    Viganò, W; Effinger, E; Venturini, G G; Zamantzas, C

    2012-01-01

    Three Different Concepts of High Dynamic Range and Dependability Optimised Current Measurement Digitisers for Beam Loss Systems will be compared on this paper. The first concept is based on Current to Frequency Conversion, enhanced with an ADC for extending the dynamic range and decreasing the response time. A summary of 3 years’ worth of operational experience with such a system for LHC beam loss monitoring will be given. The second principle is based on an Adaptive Current to Frequency Converter implemented in an ASIC. The basic parameters of the circuit are discussed and compared with measurements. Several measures are taken to harden both circuits against single event effects and to make them tolerant for operation in radioactive environments. The third circuit is based on a Fully Differential Integrator for enhanced dynamic range, where laboratory and test installation measurements will be presented. All circuits are designed to avoid any dead time in the acquisition and have reliability and fail safe...

  14. Avoidant personality disorder versus social phobia: the significance of childhood neglect.

    Directory of Open Access Journals (Sweden)

    Ingeborg Eikenaes

    Full Text Available Avoidant personality disorder (AvPD and social phobia (SP are common disorders both in the community and in clinical settings. Whether the two disorders represent different severity levels of social anxiety disorder is currently in dispute. The relationship between AvPD and SP is probably more complex than previously assumed. Several environmental, temperamental, and constitutional factors may play a role in the etiology of AvPD and SP. Better knowledge about childhood experiences may shed light on similarities and differences between the two disorders. The aim of this study was to compare self-reported childhood experiences in AvPD and SP patients.This is a cross-sectional multi-site study of 91 adult patients with AvPD and/ or SP. We compared patients with AvPD with and without SP (AvPD group to patients with SP without AvPD (SP group.The patients were examined using structured diagnostic interviews and self-report measures, including Child Trauma Questionnaire, Parental Bonding Instrument, and Adult Temperament Questionnaire.Both AvPD and SP were associated with negative childhood experiences. AvPD patients reported more severe childhood neglect than patients with SP, most pronounced for physical neglect. The difference between the disorders in neglect remained significant after controlling for temperamental factors and concurrent abuse.The study indicates that childhood neglect is a risk factor for AvPD and may be one contributing factor to phenomenological differences between AvPD and SP.

  15. Avoidant personality disorder versus social phobia: the significance of childhood neglect.

    Science.gov (United States)

    Eikenaes, Ingeborg; Egeland, Jens; Hummelen, Benjamin; Wilberg, Theresa

    2015-01-01

    Avoidant personality disorder (AvPD) and social phobia (SP) are common disorders both in the community and in clinical settings. Whether the two disorders represent different severity levels of social anxiety disorder is currently in dispute. The relationship between AvPD and SP is probably more complex than previously assumed. Several environmental, temperamental, and constitutional factors may play a role in the etiology of AvPD and SP. Better knowledge about childhood experiences may shed light on similarities and differences between the two disorders. The aim of this study was to compare self-reported childhood experiences in AvPD and SP patients. This is a cross-sectional multi-site study of 91 adult patients with AvPD and/ or SP. We compared patients with AvPD with and without SP (AvPD group) to patients with SP without AvPD (SP group). The patients were examined using structured diagnostic interviews and self-report measures, including Child Trauma Questionnaire, Parental Bonding Instrument, and Adult Temperament Questionnaire. Both AvPD and SP were associated with negative childhood experiences. AvPD patients reported more severe childhood neglect than patients with SP, most pronounced for physical neglect. The difference between the disorders in neglect remained significant after controlling for temperamental factors and concurrent abuse. The study indicates that childhood neglect is a risk factor for AvPD and may be one contributing factor to phenomenological differences between AvPD and SP.

  16. Comparison between Different Control Strategies of a Z-Source Inverter Based Dynamic Voltage Restorer

    Directory of Open Access Journals (Sweden)

    Abolfazl Kazemdehdashti

    2013-01-01

    Full Text Available In this paper, dynamic voltage restorer (DVR compensation methods are compared to each other for the load side connected shunt converter topology of z-source inverter based DVR to choose the best method. Four different topologies are recognized for DVR that two of them have energy storage devices, and two topologies have no energy storage that take ener\\-gy from the grid during the period of compensation. Here the load side connected shunt converter topology that takes necessary energy from the grid is used. Pre-sag compensation, in-phase compensation, energy-optimized methods are the three DVR compensation methods that studied and compared. A deep analysis through different diagrams would show the advantages or disadvantages of each compensation method. Equations for all methods are derived and the characteristics of algorithms are compared with each other. The simulation results done by SIMULINK/ MATLAB shows compensating by this topology based on the compensation methods.

  17. Diversity and dynamics of dominant and rare bacterial taxa in replicate sequencing batch reactors operated under different solids retention time

    KAUST Repository

    Bagchi, Samik

    2014-10-19

    In this study, 16S rRNA gene pyrosequencing was applied in order to provide a better insight on the diversity and dynamics of total, dominant, and rare bacterial taxa in replicate lab-scale sequencing batch reactors (SBRs) operated at different solids retention time (SRT). Rank-abundance curves showed few dominant operational taxonomic units (OTUs) and a long tail of rare OTUs in all reactors. Results revealed that there was no detectable effect of SRT (2 vs. 10 days) on Shannon diversity index and OTU richness of both dominant and rare taxa. Nonmetric multidimensional scaling analysis showed that the total, dominant, and rare bacterial taxa were highly dynamic during the entire period of stable reactor performance. Also, the rare taxa were more dynamic than the dominant taxa despite expected low invasion rates because of the use of sterile synthetic media.

  18. Neutron to proton mass difference, parton distribution functions and baryon resonances from dynamics on the Lie group u(3)

    DEFF Research Database (Denmark)

    Trinhammer, Ole

    PiMinus invariant mass in B decays. We give a controversial prediction of the relative neutron to proton mass difference 0.138 % as originating in period doublings of certain parametric states. The group space dynamics communicates with real space via the exterior derivative which projects out quark and gluon...

  19. Dynamic headspace-gas-chromatography-olfactometry analysis of different anatomical parts of lovage (Levisticum officinale Koch.) at eight growing stages

    NARCIS (Netherlands)

    Bylaite, E.; Roozen, J.P.; Legger, A.; Venskutonis, R.P.; Posthumus, M.A.

    2000-01-01

    Volatiles of five different parts of lovage (leaves, stems, flowers, seeds, and roots) were isolated by dynamic headspace (DHS) method and analyzed by GC-FID and GC-olfactometry (GC-O) techniques. In total, 98 compounds were identified in the samples, of which 41 are reported as lovage volatiles for

  20. Diversity and dynamics of dominant and rare bacterial taxa in replicate sequencing batch reactors operated under different solids retention time

    KAUST Repository

    Bagchi, Samik; Garcia Tellez, Berenice; Rao, Hari Ananda; Lamendella, Regina; Saikaly, Pascal

    2014-01-01

    In this study, 16S rRNA gene pyrosequencing was applied in order to provide a better insight on the diversity and dynamics of total, dominant, and rare bacterial taxa in replicate lab-scale sequencing batch reactors (SBRs) operated at different

  1. Drought Dynamics and Vegetation Productivity in Different Land Management Systems of Eastern Cape, South Africa—A Remote Sensing Perspective

    Directory of Open Access Journals (Sweden)

    Valerie Graw

    2017-09-01

    Full Text Available Eastern Cape Province in South Africa has experienced extreme drought events during the last decade. In South Africa, different land management systems exist belonging to two different land tenure classes: commercial large scale farming and communal small-scale subsistence farming. Communal lands are often reported to be affected by land degradation and drought events among others considered as trigger for this process. Against this background, we analyzed vegetation response to drought in different land management and land tenure systems through assessing vegetation productivity trends and monitoring the intensity, frequency and distribution of the drought hazard in grasslands and communal and commercial croplands during drought and non-drought conditions. For the observation period 2000–2016, we used time series of 250 m Vegetation Condition Index (VCI based on the Moderate Resolution Imaging Spectroradiometer (MODIS Enhanced Vegetation Index (EVI and Climate Hazard Group InfraRed Precipitation with Station data (CHIRPS precipitation data with 5 km resolution. For the assessment of vegetation dynamics, we: (1 analyzed vegetation productivity in Eastern Cape over the last 16 years with EVI; (2 analyzed the impact of drought events on vegetation productivity in grasslands as well as commercial and communal croplands; and (3 compared precipitation-vegetation dynamics between the drought season 2015/2016 and the non-drought season 2011/2012. Change in total annual vegetation productivity could detect drought years while drought dynamics during the season could be rather monitored by the VCI. Correlation of vegetation condition and precipitation indicated areas experiencing significant vegetation productivity trends showing low and even negative correlation coefficients indicating other drivers for productivity change and drought impact besides rainfall.

  2. Assessment of the Performance of Three Dynamical Climate Downscaling Methods Using Different Land Surface Information over China

    Directory of Open Access Journals (Sweden)

    Peng Liu

    2018-03-01

    Full Text Available This study aims to assess the performance of different dynamical downscaling methods using updated land surface information. Particular attention is given to obtaining high-resolution climate information over China by the combination of an appropriate dynamical downscaling method and updated land surface information. Two group experiments using two land surface datasets are performed, including default Weather Research and Forecasting (WRF land surface data (OLD and accurate dynamically accordant MODIS data (NEW. Each group consists of three types of experiments for the summer of 2014, including traditional continuous integration (CT, spectral nudging (SN, and re-initialization (Re experiments. The Weather Research and Forecasting (WRF model is used to dynamically downscale ERA-Interim (reanalysis of the European Centre for Medium-Range Weather Forecast, ECMWF data with a grid spacing of 30 km over China. The simulations are evaluated via comparison with observed conventional meteorological variables, showing that the CT method, which notably overestimates 2 m temperature and underestimates 2 m relative humidity across China, performs the worst; the SN and Re runs outperform the CT method, and the Re shows the smallest RMSE (root means square error. A comparison of observed and simulated precipitation shows that the SN simulation is closest to the observed data, while the CT and Re simulations overestimate precipitation south of the Yangtze River. Compared with the OLD group, the RMSE values of temperature and relative humidity are significantly improved in CT and SN, and there is smaller improved in Re. However, obvious improvements in precipitation are not evident.

  3. The dynamics of histamine level in patients with chronic urticaria under the influence of different methods of treatment.

    Directory of Open Access Journals (Sweden)

    Dytyatkovska Ye.M.

    2014-11-01

    Full Text Available There was studied the efficiency of different methods of chronic urticaria treatment. All patients were divided into 2 groups depending on treatment scteme. The paper shows the dynamics of histamine level in blood plasma, intestine disbiosis in patients with chronic urticaria under the influence of different treatment complexes. It was proved that there exists the correlation between the serum histamine level and method of treatment. Intro¬ducing bionorm into the treatment allows to decrease histamine level and correspondingly to significantly improve clinical effect and patients’ life quality.

  4. Dynamic screening and electron dynamics in low-dimensional metal systems

    International Nuclear Information System (INIS)

    Silkin, V.M.; Quijada, M.; Vergniory, M.G.; Alducin, M.; Borisov, A.G.; Diez Muino, R.; Juaristi, J.I.; Sanchez-Portal, D.; Chulkov, E.V.; Echenique, P.M.

    2007-01-01

    Recent advances in the theoretical description of dynamic screening and electron dynamics in metallic media are reviewed. The time-dependent building-up of screening in different situations is addressed. Perturbative and non-perturbative theories are used to study electron dynamics in low-dimensional systems, such as metal clusters, image states, surface states and quantum wells. Modification of the electronic lifetimes due to confinement effects is analyzed as well

  5. CO2 Dynamics in winter wheat and canola under different management practices in the Southern Great Plains

    Science.gov (United States)

    Wagle, P.; Manjunatha, P.; Gowda, P. H.; Northup, B. K.; Neel, J. P. S.; Turner, K.; Steiner, J. L.

    2017-12-01

    Rising atmospheric carbon dioxide (CO2) concentration and increased air temperature and climatic variability concerns have prompted considerable interest regarding CO2 dynamics of terrestrial ecosystems in response to major climatic and biophysical factors. However, detailed information on CO2 dynamics in winter wheat (Triticum aestivum L.) and canola (Brassica napus L.) under different agricultural management practices is lacking. As a part of the GRL-FLUXNET, a cluster of eight eddy covariance (EC) systems was deployed on the 420-ha Grazinglands Research on agroEcosystems and the ENvironment (GREEN) Farm at the United States Department of Agriculture, Agricultural Research Service (USDA-ARS), Grazinglands Research Laboratory (GRL), El Reno, OK. The GRL is also one of 18 USDA-ARS Long-Term Agroecosystem Research (LTAR) network sites in the United States. A 4-year crop rotation plan at the farm includes winter wheat for grain only, graze-grain, and graze-out, and canola under conventional till and no-till management conditions. Biometric measurements such as biomass, leaf area index (LAI), canopy cover %, canopy height, and chlorophyll content were collected approximately every 16 days to coincide with Landsat satellite overpass dates. As expected, biomass and LAI were highest in the grain only wheat fields followed by graze-grain and graze-out wheat fields, but they were similar for till and no-till wheat fields within the same grazing practice. Biomass and LAI were similar in till and no-till canola in fall 2016, but both were substantially lower in no-till compared to tilled canola during spring 2017 due to more severe winter damage. Because net ecosystem CO2 exchange (NEE) is strongly regulated by vegetation cover, the magnitudes of NEE were highest in the grain only wheat fields due to more biomass and LAI, followed by graze-grain and graze-out wheat fields. Similarly, the magnitudes of NEE were also higher in tilled canola (i.e., higher biomass and LAI) than

  6. Comparative Computed Flow Dynamic Analysis of Different Optimization Techniques in Left Main Either Provisional or Culotte Stenting.

    Science.gov (United States)

    Rigatelli, Gianluca; Dell'Avvocata, Fabio; Zuin, Marco; Giatti, Sara; Duong, Khanh; Pham, Trung; Tuan, Nguyen Si; Vassiliev, Dobrin; Daggubati, Ramesh; Nguyen, Thach

    2017-12-01

    Provisional and culotte are the most commonly used techniques in left main (LM) stenting. The impact of different post-dilation techniques on fluid dynamic of LM bifurcation has not been yet investigated. The aim of this study is to evaluate, by means of computational fluid dynamic analysis (CFD), the impact of different post-dilation techniques including proximal optimization technique (POT), kissing balloon (KB), POT-Side-POT and POT-KB-POT, 2-steps Kissing (2SK) and Snuggle Kissing balloon (SKB) on flow dynamic profile after LM provisional or culotte stenting. We considered an LM-LCA-LCX bifurcation reconstructed after reviewing 100 consecutive patients (mean age 71.4 ± 9.3 years, 49 males) with LM distal disease. The diameters of LAD and LCX were modelled according to the Finnet's law as following: LM 4.5 mm, LAD 3.5 mm, LCX 2.75 mm, with bifurcation angle set up at 55°. Xience third-generation stent (Abbot Inc., USA) was reconstructed and virtually implanted in provisional/cross-over and culotte fashion. POT, KB, POT-side-POT, POT-KB-POT, 2SK and SKB were virtually applied and analyzed in terms of the wall shear stress (WSS). Analyzing the provisional stenting, the 2SK and KB techniques had a statistically significant lower impact on the WSS at the carina, while POT seemed to obtain a neutral effect. In the wall opposite to the carina, the more physiological profile has been obtained by KB and POT with higher WSS value and smaller surface area of the lower WSS. In culotte stenting, at the carina, POT-KB-POT and 2SK had a very physiological profile; while at the wall opposite to the carina, 2SK and POT-KB-POT decreased significantly the surface area of the lower WSS compared to the other techniques. From the fluid dynamic point of view in LM provisional stenting, POT, 2SK and KB showed a similar beneficial impact on the bifurcation rheology, while in LM culotte stenting, POT-KB-POT and 2SK performed slightly better than the other techniques, probably

  7. Algebraic dynamics solutions and algebraic dynamics algorithm for nonlinear partial differential evolution equations of dynamical systems

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Using functional derivative technique in quantum field theory, the algebraic dy-namics approach for solution of ordinary differential evolution equations was gen-eralized to treat partial differential evolution equations. The partial differential evo-lution equations were lifted to the corresponding functional partial differential equations in functional space by introducing the time translation operator. The functional partial differential evolution equations were solved by algebraic dynam-ics. The algebraic dynamics solutions are analytical in Taylor series in terms of both initial functions and time. Based on the exact analytical solutions, a new nu-merical algorithm—algebraic dynamics algorithm was proposed for partial differ-ential evolution equations. The difficulty of and the way out for the algorithm were discussed. The application of the approach to and computer numerical experi-ments on the nonlinear Burgers equation and meteorological advection equation indicate that the algebraic dynamics approach and algebraic dynamics algorithm are effective to the solution of nonlinear partial differential evolution equations both analytically and numerically.

  8. Comparative daily dynamics of mycorrhizal fungal hyphae across differing ecosystems using an automated minirhizotron and sensor network

    Science.gov (United States)

    Allen, M. F.

    2013-05-01

    allow us to undertake comparative analyses of soil organisms, such as fungi, on time scale at which the respond to changing weather events and to track individual hyphae to determine turnover, the crucial missing datapoint in carbon modeling. They also tell us that each different ecosystem responds differently, and non-linearly to changes in T and SM, with dramatic shifts in C fluxes. If we are to obtain a mechanistic understanding of global carbon dynamics, we need to understand how soil organisms respond to both fine-scale and coarse scale shifts in different ecosystems.

  9. Exposure to the self-face facilitates identification of dynamic facial expressions: influences on individual differences.

    Science.gov (United States)

    Li, Yuan Hang; Tottenham, Nim

    2013-04-01

    A growing literature suggests that the self-face is involved in processing the facial expressions of others. The authors experimentally activated self-face representations to assess its effects on the recognition of dynamically emerging facial expressions of others. They exposed participants to videos of either their own faces (self-face prime) or faces of others (nonself-face prime) prior to a facial expression judgment task. Their results show that experimentally activating self-face representations results in earlier recognition of dynamically emerging facial expression. As a group, participants in the self-face prime condition recognized expressions earlier (when less affective perceptual information was available) compared to participants in the nonself-face prime condition. There were individual differences in performance, such that poorer expression identification was associated with higher autism traits (in this neurocognitively healthy sample). However, when randomized into the self-face prime condition, participants with high autism traits performed as well as those with low autism traits. Taken together, these data suggest that the ability to recognize facial expressions in others is linked with the internal representations of our own faces. PsycINFO Database Record (c) 2013 APA, all rights reserved.

  10. Dynamic Properties of the Painter Street Overpass at Different Levels of Vibration

    DEFF Research Database (Denmark)

    Ventura, C. E.; Brincker, Rune; Andersen, P.

    2005-01-01

    This paper describes the results from a series of ambient vibration studies conducted on the Painter Street Overpass in Rio Dell, California. Painter Street is a two-span, skewed reinforced concrete bridge with two single piers near the middle and monolithic abutments, typical of bridge overpasses...... from analyses of selected strong motion records. The magnitude of the events investigated ranges from ML=4.4 to ML=6.9, which produced accelerations of up to 0.54g at the free field site, 1.3g at the abutments, and 0.86g on the deck. The results of this study indicate that the overall dynamic...... properties of the bridge are very sensitive to the level of ground shaking and that soil-structure interaction is very important for this type structural system. Although the superstructure exhibited a nearly elastic response, the motions at the abutments and base of piers were significantly different...

  11. Numerical investigations of rib fracture failure models in different dynamic loading conditions.

    Science.gov (United States)

    Wang, Fang; Yang, Jikuang; Miller, Karol; Li, Guibing; Joldes, Grand R; Doyle, Barry; Wittek, Adam

    2016-01-01

    Rib fracture is one of the most common thoracic injuries in vehicle traffic accidents that can result in fatalities associated with seriously injured internal organs. A failure model is critical when modelling rib fracture to predict such injuries. Different rib failure models have been proposed in prediction of thorax injuries. However, the biofidelity of the fracture failure models when varying the loading conditions and the effects of a rib fracture failure model on prediction of thoracic injuries have been studied only to a limited extent. Therefore, this study aimed to investigate the effects of three rib failure models on prediction of thoracic injuries using a previously validated finite element model of the human thorax. The performance and biofidelity of each rib failure model were first evaluated by modelling rib responses to different loading conditions in two experimental configurations: (1) the three-point bending on the specimen taken from rib and (2) the anterior-posterior dynamic loading to an entire bony part of the rib. Furthermore, the simulation of the rib failure behaviour in the frontal impact to an entire thorax was conducted at varying velocities and the effects of the failure models were analysed with respect to the severity of rib cage damages. Simulation results demonstrated that the responses of the thorax model are similar to the general trends of the rib fracture responses reported in the experimental literature. However, they also indicated that the accuracy of the rib fracture prediction using a given failure model varies for different loading conditions.

  12. Herbage Dynamics and Soils of two Different Sites of Calotropis ...

    African Journals Online (AJOL)

    To determine herbage dynamics, herbs in each quadrat of the experimental sites were harvested, sorted out according to species, counted and identified in the herbarium. Simpson's index, D = ∑Pi2 was used to obtain relative frequencies and abundance of species. Soil samples were derived from the quadrats and ...

  13. Early-Life Telomere Dynamics Differ between the Sexes and Predict Growth in the Barn Swallow (Hirundo rustica.

    Directory of Open Access Journals (Sweden)

    Marco Parolini

    Full Text Available Telomeres are conserved DNA-protein structures at the termini of eukaryotic chromosomes which contribute to maintenance of genome integrity, and their shortening leads to cell senescence, with negative consequences for organismal functions. Because telomere erosion is influenced by extrinsic and endogenous factors, telomere dynamics may provide a mechanistic basis for evolutionary and physiological trade-offs. Yet, knowledge of fundamental aspects of telomere biology under natural selection regimes, including sex- and context-dependent variation in early-life, and the covariation between telomere dynamics and growth, is scant. In this study of barn swallows (Hirundo rustica we investigated the sex-dependent telomere erosion during nestling period, and the covariation between relative telomere length and body and plumage growth. Finally, we tested whether any covariation between growth traits and relative telomere length depends on the social environment, as influenced by sibling sex ratio. Relative telomere length declined on average over the period of nestling maximal growth rate (between 7 and 16 days of age and differently covaried with initial relative telomere length in either sex. The frequency distribution of changes in relative telomere length was bimodal, with most nestlings decreasing and some increasing relative telomere length, but none of the offspring traits predicted the a posteriori identified group to which individual nestlings belonged. Tail and wing length increased with relative telomere length, but more steeply in males than females, and this relationship held both at the within- and among-broods levels. Moreover, the increase in plumage phenotypic values was steeper when the sex ratio of an individual's siblings was female-biased. Our study provides evidence for telomere shortening during early life according to subtly different dynamics in either sex. Furthermore, it shows that the positive covariation between growth and

  14. Hypopituitarism following traumatic brain injury: prevalence is affected by the use of different dynamic tests and different normal values.

    Science.gov (United States)

    Kokshoorn, Nieke E; Wassenaar, Moniek J E; Biermasz, Nienke R; Roelfsema, Ferdinand; Smit, Johannes W A; Romijn, Johannes A; Pereira, Alberto M

    2010-01-01

    Traumatic brain injury (TBI) has emerged as an important cause of hypopituitarism. However, considerable variations in the prevalence of hypopituitarism are reported. These can partly be explained by severity of trauma and timing of hormonal evaluation, but may also be dependent on endocrine tests and criteria used for diagnosis of hypopituitarism. Systematic review of studies reporting prevalence of hypopituitarism in adults >or=1 year after TBI focusing on used (dynamic) tests and biochemical criteria. We included data from 14 studies with a total of 931 patients. There was considerable variation in definition of hypopituitarism. Overall, reported prevalences of severe GH deficiency varied between 2 and 39%. Prevalences were 8-20% using the GHRH-arginine test (cutoff hypopituitarism after TBI are in part caused by differences in definitions, endocrine assessments of hypopituitarism, and confounding factors. These methodological issues prohibit simple generalizations of results of original studies on TBI-associated hypopituitarism in the perspective of meta-analyses or reviews.

  15. Impact of different disassembly line balancing algorithms on the performance of dynamic kanban system for disassembly line

    Science.gov (United States)

    Kizilkaya, Elif A.; Gupta, Surendra M.

    2005-11-01

    In this paper, we compare the impact of different disassembly line balancing (DLB) algorithms on the performance of our recently introduced Dynamic Kanban System for Disassembly Line (DKSDL) to accommodate the vagaries of uncertainties associated with disassembly and remanufacturing processing. We consider a case study to illustrate the impact of various DLB algorithms on the DKSDL. The approach to the solution, scenario settings, results and the discussions of the results are included.

  16. Effects of different per translational kinetics on the dynamics of a core circadian clock model.

    Science.gov (United States)

    Nieto, Paula S; Revelli, Jorge A; Garbarino-Pico, Eduardo; Condat, Carlos A; Guido, Mario E; Tamarit, Francisco A

    2015-01-01

    Living beings display self-sustained daily rhythms in multiple biological processes, which persist in the absence of external cues since they are generated by endogenous circadian clocks. The period (per) gene is a central player within the core molecular mechanism for keeping circadian time in most animals. Recently, the modulation PER translation has been reported, both in mammals and flies, suggesting that translational regulation of clock components is important for the proper clock gene expression and molecular clock performance. Because translational regulation ultimately implies changes in the kinetics of translation and, therefore, in the circadian clock dynamics, we sought to study how and to what extent the molecular clock dynamics is affected by the kinetics of PER translation. With this objective, we used a minimal mathematical model of the molecular circadian clock to qualitatively characterize the dynamical changes derived from kinetically different PER translational mechanisms. We found that the emergence of self-sustained oscillations with characteristic period, amplitude, and phase lag (time delays) between per mRNA and protein expression depends on the kinetic parameters related to PER translation. Interestingly, under certain conditions, a PER translation mechanism with saturable kinetics introduces longer time delays than a mechanism ruled by a first-order kinetics. In addition, the kinetic laws of PER translation significantly changed the sensitivity of our model to parameters related to the synthesis and degradation of per mRNA and PER degradation. Lastly, we found a set of parameters, with realistic values, for which our model reproduces some experimental results reported recently for Drosophila melanogaster and we present some predictions derived from our analysis.

  17. Estimation of Road Friction Coefficient in Different Road Conditions Based on Vehicle Braking Dynamics

    Science.gov (United States)

    Zhao, You-Qun; Li, Hai-Qing; Lin, Fen; Wang, Jian; Ji, Xue-Wu

    2017-07-01

    The accurate estimation of road friction coefficient in the active safety control system has become increasingly prominent. Most previous studies on road friction estimation have only used vehicle longitudinal or lateral dynamics and often ignored the load transfer, which tends to cause inaccurate of the actual road friction coefficient. A novel method considering load transfer of front and rear axles is proposed to estimate road friction coefficient based on braking dynamic model of two-wheeled vehicle. Sliding mode control technique is used to build the ideal braking torque controller, which control target is to control the actual wheel slip ratio of front and rear wheels tracking the ideal wheel slip ratio. In order to eliminate the chattering problem of the sliding mode controller, integral switching surface is used to design the sliding mode surface. A second order linear extended state observer is designed to observe road friction coefficient based on wheel speed and braking torque of front and rear wheels. The proposed road friction coefficient estimation schemes are evaluated by simulation in ADAMS/Car. The results show that the estimated values can well agree with the actual values in different road conditions. The observer can estimate road friction coefficient exactly in real-time and resist external disturbance. The proposed research provides a novel method to estimate road friction coefficient with strong robustness and more accurate.

  18. Internationally Adopted Children from Non-European Countries: General Development during the First Two Years in the Adoptive Family

    Directory of Open Access Journals (Sweden)

    Monica Dalen

    2012-01-01

    Full Text Available Internationally adopted children are often delayed in their development and demonstrate more behaviour problems than nonadopted children due to adverse preadoption circumstances. This is especially true for children adopted from Eastern European countries. Few studies have focused on children adopted from non-European countries. This paper presents results from an ongoing longitudinal study of 119 internationally adopted children from non-European countries during their first two years in Norway. Several scales measuring different aspects of the children’s development are included in the study: communication and gross motor development, temperamental characteristics, and behaviour problems. The results show that internationally adopted children are delayed in their general development when they first arrive in their adoptive families. After two years the children have made significant progress in development. However, they still lag behind in communication and motor skills compared to non-adopted children. The temperamental characteristics seem very stable from time of adoption until two years after adoption. The children demonstrate a low frequency of behaviour problems. However, the behaviour problems have changed during the two years. At time of adoption they show more nonphysically challenging behaviour while after two years their physically challenging behaviour has increased.

  19. Internationally adopted children from non-European countries: general development during the first two years in the adoptive family.

    Science.gov (United States)

    Dalen, Monica; Theie, Steinar

    2012-01-01

    Internationally adopted children are often delayed in their development and demonstrate more behaviour problems than nonadopted children due to adverse preadoption circumstances. This is especially true for children adopted from Eastern European countries. Few studies have focused on children adopted from non-European countries. This paper presents results from an ongoing longitudinal study of 119 internationally adopted children from non-European countries during their first two years in Norway. Several scales measuring different aspects of the children's development are included in the study: communication and gross motor development, temperamental characteristics, and behaviour problems. The results show that internationally adopted children are delayed in their general development when they first arrive in their adoptive families. After two years the children have made significant progress in development. However, they still lag behind in communication and motor skills compared to non-adopted children. The temperamental characteristics seem very stable from time of adoption until two years after adoption. The children demonstrate a low frequency of behaviour problems. However, the behaviour problems have changed during the two years. At time of adoption they show more nonphysically challenging behaviour while after two years their physically challenging behaviour has increased.

  20. Financial fragility and global dynamics

    International Nuclear Information System (INIS)

    Dieci, Roberto; Sordi, Serena; Vercelli, Alessandro

    2006-01-01

    This paper deals with a simple model of financial fluctuations, where a crucial role is played by the dynamic interaction between aggregate current and intertemporal financial ratios. The model results in a 4D discrete-time dynamical system-capable of generating complex dynamics-which is analyzed by means of both analytical tools, such as local stability analysis and bifurcation theory, and numerical simulations. The behavior of the model is studied for different parameter regimes. We show that its dynamic behavior is very sensitive to the parameters that represent (1) the speed of adjustment of the desired current financial ratio towards a safe level of the intertemporal one and (2) the intensity with which aggregate current financial decisions affect future financial constraints. In particular, different parameter regimes are identified, giving rise to two different 'routes' to complexity, one leading to chaotic dynamics, the other to a coexistence of attractors and path-dependence

  1. Developmental Origins of Rumination in Middle Childhood: The Roles of Early Temperament and Positive Parenting.

    Science.gov (United States)

    Schweizer, Tina H; Olino, Thomas M; Dyson, Margaret W; Laptook, Rebecca S; Klein, Daniel N

    2017-09-08

    Rumination, a thinking style characterized by a repetitive inward focus on negative cognitions, has been linked to internalizing disorders, particularly depression. Moreover, research suggests that rumination may be a cognitive vulnerability that predisposes individuals to psychopathology. Surprisingly little is known, however, about the etiology and development of rumination. The present study examined the role of specific components of child temperamental negative emotionality (sadness, fear, anger) and effortful control (inhibition), as well as parenting behaviors during early childhood on the development of rumination in middle childhood. Early childhood (age 3) temperament and parenting behaviors were assessed observationally and rumination was self-reported in middle childhood (age 9) in a large community sample (N = 425; 47.1% female). Two significant interactions emerged. First, temperamental anger interacted with inhibitory control (IC) such that high anger and low IC predicted higher levels of rumination, whereas low anger and low IC predicted lower levels of rumination. Second, IC interacted with parenting such that children with low IC and positive parenting had lower levels of rumination. In contrast, children with high IC reported similar levels of rumination regardless of parenting quality. Overall, these findings highlight the interplay of early IC with temperamental anger and positive parenting in the development of ruminative tendencies in middle childhood.

  2. Dynamic loads on human and animal surrogates at different test locations in compressed-gas-driven shock tubes

    Science.gov (United States)

    Alay, E.; Skotak, M.; Misistia, A.; Chandra, N.

    2018-01-01

    Dynamic loads on specimens in live-fire conditions as well as at different locations within and outside compressed-gas-driven shock tubes are determined by both static and total blast overpressure-time pressure pulses. The biomechanical loading on the specimen is determined by surface pressures that combine the effects of static, dynamic, and reflected pressures and specimen geometry. Surface pressure is both space and time dependent; it varies as a function of size, shape, and external contour of the specimens. In this work, we used two sets of specimens: (1) anthropometric dummy head and (2) a surrogate rodent headform instrumented with pressure sensors and subjected them to blast waves in the interior and at the exit of the shock tube. We demonstrate in this work that while inside the shock tube the biomechanical loading as determined by various pressure measures closely aligns with live-fire data and shock wave theory, significant deviations are found when tests are performed outside.

  3. Relaxation dynamics in the presence of pulse multiplicative noise sources with different correlation properties

    Science.gov (United States)

    Kargovsky, A. V.; Chichigina, O. A.; Anashkina, E. I.; Valenti, D.; Spagnolo, B.

    2015-10-01

    The relaxation dynamics of a system described by a Langevin equation with pulse multiplicative noise sources with different correlation properties is considered. The solution of the corresponding Fokker-Planck equation is derived for Gaussian white noise. Moreover, two pulse processes with regulated periodicity are considered as a noise source: the dead-time-distorted Poisson process and the process with fixed time intervals, which is characterized by an infinite correlation time. We find that the steady state of the system is dependent on the correlation properties of the pulse noise. An increase of the noise correlation causes the decrease of the mean value of the solution at the steady state. The analytical results are in good agreement with the numerical ones.

  4. What goes up must . . . Keep going up? Cultural differences in cognitive styles influence evaluations of dynamic performance.

    Science.gov (United States)

    Ferris, D Lance; Reb, Jochen; Lian, Huiwen; Sim, Samantha; Ang, Dionysius

    2018-03-01

    Past research on dynamic workplace performance evaluation has taken as axiomatic that temporal performance trends produce naïve extrapolation effects on performance ratings. That is, we naïvely assume that an individual whose performance has trended upward over time will continue to improve, and rate that individual more positively than an individual whose performance has trended downward over time-even if, on average, the 2 individuals have performed at an equivalent level. However, we argue that such naïve extrapolation effects are more pronounced in Western countries than Eastern countries, owing to Eastern countries having a more holistic cognitive style. To test our hypotheses, we examined the effect of performance trend on expectations of future performance and ratings of past performance across 2 studies: Study 1 compares the magnitude of naïve extrapolation effects among Singaporeans primed with either a more or less holistic cognitive style, and Study 2 examines holistic cognitive style as a mediating mechanism accounting for differences in the magnitude of naïve extrapolation effects between American and Chinese raters. Across both studies, we found support for our predictions that dynamic performance trends have less impact on the ratings of more holistic thinkers. Implications for the dynamic performance and naïve extrapolation literatures are discussed. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  5. Tuning of electronic properties and dynamical stability of graphene oxide with different functional groups

    Science.gov (United States)

    Dabhi, Shweta D.; Jha, Prafulla K.

    2017-09-01

    The structural, electronic and vibrational properties of graphene oxide (GO) with varying proportion of epoxy and hydroxyl functional groups have been studied using density functional theory. The functional groups and oxygen density have an obvious influence on the electronic and vibrational properties. The dependence of band gap on associated functional groups and oxygen density shows a possibility of tuning the band gap of graphene by varying the functional groups as well as oxidation level. The absorption of high oxygen content in graphene leads to the gap opening and resulting in a transition from semimetal to semiconductor. Phonon dispersion curves show no imaginary frequency or no softening of any phonon mode throughout the Brillouin zone which confirms the dynamical stability of all considered GO models. Different groups and different oxygen density result into the varying characteristics of phonon modes. The computed results show good agreement with the experimental observations. Our results present interesting possibilities for engineering the electronic properties of graphene and GO and impact the fabrication of new electronics.

  6. Sparse dynamical Boltzmann machine for reconstructing complex networks with binary dynamics

    Science.gov (United States)

    Chen, Yu-Zhong; Lai, Ying-Cheng

    2018-03-01

    Revealing the structure and dynamics of complex networked systems from observed data is a problem of current interest. Is it possible to develop a completely data-driven framework to decipher the network structure and different types of dynamical processes on complex networks? We develop a model named sparse dynamical Boltzmann machine (SDBM) as a structural estimator for complex networks that host binary dynamical processes. The SDBM attains its topology according to that of the original system and is capable of simulating the original binary dynamical process. We develop a fully automated method based on compressive sensing and a clustering algorithm to construct the SDBM. We demonstrate, for a variety of representative dynamical processes on model and real world complex networks, that the equivalent SDBM can recover the network structure of the original system and simulates its dynamical behavior with high precision.

  7. Difference between the vocalizations of two sister species of pigeons explained in dynamical terms.

    Science.gov (United States)

    Alonso, R Gogui; Kopuchian, Cecilia; Amador, Ana; Suarez, Maria de Los Angeles; Tubaro, Pablo L; Mindlin, Gabriel B

    2016-05-01

    Vocal communication is an unique example, where the nonlinear nature of the periphery can give rise to complex sounds even when driven by simple neural instructions. In this work we studied the case of two close-related bird species, Patagioenas maculosa and Patagioenas picazuro, whose vocalizations differ only in the timbre. The temporal modulation of the fundamental frequency is similar in both cases, differing only in the existence of sidebands around the fundamental frequency in the P. maculosa. We tested the hypothesis that the qualitative difference between these vocalizations lies in the nonlinear nature of the syrinx. In particular, we propose that the roughness of maculosa's vocalizations is due to an asymmetry between the right and left vibratory membranes, whose nonlinear dynamics generate the sound. To test the hypothesis, we generated a biomechanical model for vocal production with an asymmetric parameter Q with which we can control the level of asymmetry between these membranes. Using this model we generated synthetic vocalizations with the principal acoustic features of both species. In addition, we confirmed the anatomical predictions by making post mortem inspection of the syrinxes, showing that the species with tonal song (picazuro) has a more symmetrical pair of membranes compared to maculosa.

  8. Chronic Effects of Different Rest Intervals Between Sets on Dynamic and Isometric Muscle Strength and Muscle Activity in Trained Older Women.

    Science.gov (United States)

    Jambassi Filho, José Claudio; Gurjão, André Luiz Demantova; Ceccato, Marilia; Prado, Alexandre Konig Garcia; Gallo, Luiza Herminia; Gobbi, Sebastião

    2017-09-01

    This study investigated the chronic effects of different rest intervals (RIs) between sets on dynamic and isometric muscle strength and muscle activity. We used a repeated-measures design (pretraining and posttraining) with independent groups (different RI). Twenty-one resistance-trained older women (66.4 ± 4.4 years) were randomly assigned to either a 1-minute RI group (G-1 min; n = 10) or 3-minute RI group (G-3 min; n = 11). Both groups completed 3 supervised sessions per week during 8 weeks. In each session, participants performed 3 sets of 15 repetitions of leg press exercise, with a load that elicited muscle failure in the third set. Fifteen maximum repetitions, maximal voluntary contraction, peak rate of force development, and integrated electromyography activity of the vastus lateralis and vastus medialis muscles were assessed pretraining and posttraining. There was a significant increase in load of 15 maximum repetitions posttraining for G-3 min only (3.6%; P 0.05). The findings suggest that different RIs between sets did not influence dynamic and isometric muscle strength and muscle activity in resistance-trained older women.

  9. Carbon stocks and dynamics at different successional stages in an Afromontane tropical forest

    Science.gov (United States)

    Nyirambangutse, Brigitte; Zibera, Etienne; Uwizeye, Félicien K.; Nsabimana, Donat; Bizuru, Elias; Pleijel, Håkan; Uddling, Johan; Wallin, Göran

    2017-03-01

    As a result of different types of disturbance, forests are a mixture of stands at different stages of ecological succession. Successional stage is likely to influence forest productivity and carbon storage, linking the degree of forest disturbance to the global carbon cycle and climate. Although tropical montane forests are an important part of tropical forest ecosystems (ca. 8 %, elevation > 1000 m a.s.l.), there are still significant knowledge gaps regarding the carbon dynamics and stocks of these forests, and how these differ between early (ES) and late successional (LS) stages. This study examines the carbon (C) stock, relative growth rate (RGR) and net primary production (NPP) of ES and LS forest stands in an Afromontane tropical rainforest using data from inventories of quantitatively important ecosystem compartments in fifteen 0.5 ha plots in Nyungwe National Park in Rwanda. The total C stock was 35 % larger in LS compared to ES plots due to significantly larger above-ground biomass (AGB; 185 and 76 Mg C ha-1 in LS and ES plots), while the soil and root C stock (down to 45 cm depth in the mineral soil) did not significantly differ between the two successional stages (178 and 204 Mg C ha-1 in LS and ES plots). The main reasons for the difference in AGB were that ES trees had significantly lower stature and wood density compared to LS trees. However, ES and LS stands had similar total NPP (canopy, wood and roots of all plots ˜ 9.4 Mg C ha-1) due to counterbalancing effects of differences in AGB (higher in LS stands) and RGR (higher in ES stands). The AGB in the LS plots was considerably higher than the average value reported for old-growth tropical montane forest of south-east Asia and Central and South America at similar elevations and temperatures, and of the same magnitude as in tropical lowland forest of these regions. The results of this study highlight the importance of accounting for disturbance regimes and differences in wood density and allometry of

  10. An integrated, multisensor system for the continuous monitoring of water dynamics in rice fields under different irrigation regimes.

    Science.gov (United States)

    Chiaradia, Enrico Antonio; Facchi, Arianna; Masseroni, Daniele; Ferrari, Daniele; Bischetti, Gian Battista; Gharsallah, Olfa; Cesari de Maria, Sandra; Rienzner, Michele; Naldi, Ezio; Romani, Marco; Gandolfi, Claudio

    2015-09-01

    The cultivation of rice, one of the most important staple crops worldwide, has very high water requirements. A variety of irrigation practices are applied, whose pros and cons, both in terms of water productivity and of their effects on the environment, are not completely understood yet. The continuous monitoring of irrigation and rainfall inputs, as well as of soil water dynamics, is a very important factor in the analysis of these practices. At the same time, however, it represents a challenging and costly task because of the complexity of the processes involved, of the difference in nature and magnitude of the driving variables and of the high variety of field conditions. In this paper, we present the prototype of an integrated, multisensor system for the continuous monitoring of water dynamics in rice fields under different irrigation regimes. The system consists of the following: (1) flow measurement devices for the monitoring of irrigation supply and tailwater drainage; (2) piezometers for groundwater level monitoring; (3) level gauges for monitoring the flooding depth; (4) multilevel tensiometers and moisture sensor clusters to monitor soil water status; (5) eddy covariance station for the estimation of evapotranspiration fluxes and (6) wireless transmission devices and software interface for data transfer, storage and control from remote computer. The system is modular and it is replicable in different field conditions. It was successfully applied over a 2-year period in three experimental plots in Northern Italy, each one with a different water management strategy. In the paper, we present information concerning the different instruments selected, their interconnections and their integration in a common remote control scheme. We also provide considerations and figures on the material and labour costs of the installation and management of the system.

  11. Computational Fluid Dynamics (CFD) Simulations of Jet Mixing in Tanks of Different Scales

    Science.gov (United States)

    Breisacher, Kevin; Moder, Jeffrey

    2010-01-01

    For long-duration in-space storage of cryogenic propellants, an axial jet mixer is one concept for controlling tank pressure and reducing thermal stratification. Extensive ground-test data from the 1960s to the present exist for tank diameters of 10 ft or less. The design of axial jet mixers for tanks on the order of 30 ft diameter, such as those planned for the Ares V Earth Departure Stage (EDS) LH2 tank, will require scaling of available experimental data from much smaller tanks, as well designing for microgravity effects. This study will assess the ability for Computational Fluid Dynamics (CFD) to handle a change of scale of this magnitude by performing simulations of existing ground-based axial jet mixing experiments at two tank sizes differing by a factor of ten. Simulations of several axial jet configurations for an Ares V scale EDS LH2 tank during low Earth orbit (LEO) coast are evaluated and selected results are also presented. Data from jet mixing experiments performed in the 1960s by General Dynamics with water at two tank sizes (1 and 10 ft diameter) are used to evaluate CFD accuracy. Jet nozzle diameters ranged from 0.032 to 0.25 in. for the 1 ft diameter tank experiments and from 0.625 to 0.875 in. for the 10 ft diameter tank experiments. Thermally stratified layers were created in both tanks prior to turning on the jet mixer. Jet mixer efficiency was determined by monitoring the temperatures on thermocouple rakes in the tanks to time when the stratified layer was mixed out. Dye was frequently injected into the stratified tank and its penetration recorded. There were no velocities or turbulence quantities available in the experimental data. A commercially available, time accurate, multi-dimensional CFD code with free surface tracking (FLOW-3D from Flow Science, Inc.) is used for the simulations presented. Comparisons are made between computed temperatures at various axial locations in the tank at different times and those observed experimentally. The

  12. Shared genetic and environmental influences on early temperament and preschool psychiatric disorders in Hispanic twins.

    Science.gov (United States)

    Silberg, Judy L; Gillespie, Nathan; Moore, Ashlee A; Eaves, Lindon J; Bates, John; Aggen, Steven; Pfister, Elizabeth; Canino, Glorisa

    2015-04-01

    Despite an increasing recognition that psychiatric disorders can be diagnosed as early as preschool, little is known how early genetic and environmental risk factors contribute to the development of psychiatric disorders during this very early period of development. We assessed infant temperament at age 1, and attention deficit hyperactivity disorder (ADHD), oppositional defiant disorder (ODD), and separation anxiety disorder (SAD) at ages 3 through 5 years in a sample of Hispanic twins. Genetic, shared, and non-shared environmental effects were estimated for each temperamental construct and psychiatric disorder using the statistical program MX. Multivariate genetic models were fitted to determine whether the same or different sets of genes and environments account for the co-occurrence between early temperament and preschool psychiatric disorders. Additive genetic factors accounted for 61% of the variance in ADHD, 21% in ODD, and 28% in SAD. Shared environmental factors accounted for 34% of the variance in ODD and 15% of SAD. The genetic influence on difficult temperament was significantly associated with preschool ADHD, SAD, and ODD. The association between ODD and SAD was due to both genetic and family environmental factors. The temperamental trait of resistance to control was entirely accounted for by the shared family environment. There are different genetic and family environmental pathways between infant temperament and psychiatric diagnoses in this sample of Puerto Rican preschool age children.

  13. Niestymulująca tradycja: wpływ temperamentu na preferencje w sztuce

    Directory of Open Access Journals (Sweden)

    Joanna Rządkowska

    2010-11-01

    Full Text Available This study examined the effect of temperament on preferences for painted artwork. Our preferences are determined by different personality traits. The study presented here was a replication of the current study of Terror Management Theory (TMT with the structures of temperament as individual differences. The results showed significant differences in preferences for traditional and modern art, depending on the degree of harmonization of the temperamental structures. Sanguines and melancholics in the no fear condition evaluated modern art most highly, however in the fear condition they evaluated traditional art most highly. This effect confirms the importance of individual differences and the situational variability of preferences in art.

  14. Hydration dynamics in water clusters via quantum molecular dynamics simulations

    Energy Technology Data Exchange (ETDEWEB)

    Turi, László, E-mail: turi@chem.elte.hu [Department of Physical Chemistry, Eötvös Loránd University, Budapest 112, P. O. Box 32, H-1518 (Hungary)

    2014-05-28

    We have investigated the hydration dynamics in size selected water clusters with n = 66, 104, 200, 500, and 1000 water molecules using molecular dynamics simulations. To study the most fundamental aspects of relaxation phenomena in clusters, we choose one of the simplest, still realistic, quantum mechanically treated test solute, an excess electron. The project focuses on the time evolution of the clusters following two processes, electron attachment to neutral equilibrated water clusters and electron detachment from an equilibrated water cluster anion. The relaxation dynamics is significantly different in the two processes, most notably restoring the equilibrium final state is less effective after electron attachment. Nevertheless, in both scenarios only minor cluster size dependence is observed. Significantly different relaxation patterns characterize electron detachment for interior and surface state clusters, interior state clusters relaxing significantly faster. This observation may indicate a potential way to distinguish surface state and interior state water cluster anion isomers experimentally. A comparison of equilibrium and non-equilibrium trajectories suggests that linear response theory breaks down for electron attachment at 200 K, but the results converge to reasonable agreement at higher temperatures. Relaxation following electron detachment clearly belongs to the linear regime. Cluster relaxation was also investigated using two different computational models, one preferring cavity type interior states for the excess electron in bulk water, while the other simulating non-cavity structure. While the cavity model predicts appearance of several different hydrated electron isomers in agreement with experiment, the non-cavity model locates only cluster anions with interior excess electron distribution. The present simulations show that surface isomers computed with the cavity predicting potential show similar dynamical behavior to the interior clusters of

  15. Acceleration and holographic studies on different types of dynamization of external fixators of the bones

    Science.gov (United States)

    Podbielska, Halina; Kasprzak, Henryk T.; Voloshin, Arkady S.; Pennig, Dietmar; von Bally, Gert

    1992-08-01

    The unilateral axially dynamic fixator (Orthofix) was mounted on a sheep tibial shaft. Three fixation modes: static, dynamic controlled, and dynamic free were examined by means of double exposure holographic interferometry. Simultaneously, the acceleration was measured by an accelerometer and displayed on the monitor together with loading characteristics. The first exposure was made before the acting force was applied to the tibia plateau. The second one after the moment when the acceleration wave started to propagate through the specimen. We stated that in the case of dynamization less torsion occurs at the fracture site. So far, we have not been able to determine any correlation between results of holographic and accelerometric measurements.

  16. 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

  17. The impact of different phytosterols on the molecular dynamics in the hydrophobic/hydrophilic interface phosphatidylcholine- liposomes

    DEFF Research Database (Denmark)

    Hellgren, Lars; Sandelius, A.S.

    2001-01-01

    Plant sterols differ from cholesterol in having an alkyl group at Delta -24, and, in the case of stigmasterol, also a Delta -22 double bond. The effects of 10 mol% of three plant sterols (campesterol, fl-sitosterol, stigmasterol) and cholesterol on the molecular dynamics and phase behavior...... in multilamellar liposomes made from different phosphatidylcholine (PC) molecular species have been compared, utilizing the fluorescent probe Laurdan (2-dimethyl-amino-6-laurylnaphthalene). Laurdan reports the molecular mobility in the hydrophilic/hydrophobic interface of the membrane by determining the rate...... of dipolar relaxation of water molecules close to the glycerol backbone of PC. Our results showed that the Delta -24 alkyl group of plant sterols did not affect their ability to reduce molecular mobility in this region of the PC membranes. However, the plant sterols had a decreased capacity compared...

  18. The role of temperament in posttraumatic growth following death of a loved one

    Directory of Open Access Journals (Sweden)

    Ogińska-Bulik Nina

    2014-09-01

    Full Text Available The study investigates the role of temperament in posttraumatic growth among people who experienced a death of someone close. A group of 74 participants - mostly women (63.5%, aged 21 to 74 years (M=38.4; SD=15.5, who lost a parent, a child, a spouse or a partner, a sibling or a very close friend completed questionnaires measuring levels of posttraumatic growth (the Posttraumatic Growth Inventory and temperamental traits (the Formal Characteristics of Behaviour - Temperament Inventory. Results revealed that increased appreciation of life and improved relations to others are the most prevalent areas of posttraumatic growth. Findings suggest that such temperamental traits, as emotional reactivity, and to a lesser extent briskness and endurance play significant role in posttraumatic growth.

  19. Base Flip in DNA Studied by Molecular Dynamics Simulationsof Differently-Oxidized Forms of Methyl-Cytosine

    Directory of Open Access Journals (Sweden)

    Mahdi Bagherpoor Helabad

    2014-07-01

    Full Text Available Distortions in the DNA sequence, such as damage or mispairs, are specifically recognized and processed by DNA repair enzymes. Many repair proteins and, in particular, glycosylases flip the target base out of the DNA helix into the enzyme’s active site. Our molecular dynamics simulations of DNA with intact and damaged (oxidized methyl-cytosine show that the probability of being flipped is similar for damaged and intact methyl-cytosine. However, the accessibility of the different 5-methyl groups allows direct discrimination of the oxidized forms. Hydrogen-bonded patterns that vary between methyl-cytosine forms carrying a carbonyl oxygen atom are likely to be detected by the repair enzymes and may thus help target site recognition.

  20. Is Internet addiction a psychopathological condition distinct from pathological gambling?

    Science.gov (United States)

    Tonioni, Federico; Mazza, Marianna; Autullo, Gianna; Cappelluti, Roberta; Catalano, Valeria; Marano, Giuseppe; Fiumana, Valerio; Moschetti, Claudia; Alimonti, Flaminia; Luciani, Massimiliano; Lai, Carlo

    2014-06-01

    The behavioural-addiction perspective suggests that Internet addiction (IA) and pathological gambling (PG) could share similar characteristics with substance dependence. Despite the similarities between IA and PG, it is not clear whether these disorders share different or similar psychopathological conditions. The aim of the present study was to test whether IA patients presented different psychological symptoms, temperamental traits, coping strategies and relational patterns compared with PG patients. The hypothesis was that IA patients will show greater interpersonal disengagement than PG patients. Two clinical groups (31 IA patients and 11 PG patients) and a control group (38 healthy subjects) matched with the clinical groups for gender and age were enrolled. The clinical groups were gathered in a psychiatric service for IA and PG in a hospital. Anxiety, depression, coping strategies, attachment, temperament, and global assessment of functioning were measured. MANOVAs, ANOVAs and post-hoc comparisons were carried out in order to test the hypothesis. Despite IA and PG showing similar differences with the control group on the levels of depression, anxiety and global functioning, the two clinical groups showed different temperamental, coping and social patterns. Specifically IA patients compared with the PG patients showed a greater mental and behavioural disengagement associated with an important interpersonal impairment. The two clinical groups shared an impulsive coping strategy and socio-emotional impairments. Despite IA and PG patients presenting similar clinical symptoms, IA condition was characterised by a more relevant mental, behavioural, and social disengagement compared to PG condition. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. The economics of different dynamics of renewable expansion in the European context. A model-based analysis; Die Oekonomik unterschiedlicher Ausbaudynamiken erneuerbarer Energien im europaeischen Kontext. Eine modellbasierte Analyse

    Energy Technology Data Exchange (ETDEWEB)

    Wissen, Ralf

    2012-11-01

    The author of the contribution under consideration reports on the development and application of a suitable method for the quantification of economic repercussions of different dynamics of renewable expansion within Europe under consideration of the relevant framework. The realistic evaluation of the cost effects of different dynamics of renewable expansion requires a detailed illustration of the current economic, technical, political and social framework conditions of the renewables in Europe considerably.

  2. What are System Dynamics Insights?

    OpenAIRE

    Stave, K.; Zimmermann, N. S.; Kim, H.

    2016-01-01

    This paper explores the concept of system dynamics insights. In our field, the term “insight” is generally understood to mean dynamic insight, that is, a deep understanding about the relationship between structure and behavior. We argue this is only one aspect of the range of insights possible from system dynamics activities, and describe a broader range of potential system dynamics insights. We also propose an initial framework for discussion that relates different types of system dynamics a...

  3. Dynamics in Complex Coacervates

    Science.gov (United States)

    Perry, Sarah

    Understanding the dynamics of a material provides detailed information about the self-assembly, structure, and intermolecular interactions present in a material. While rheological methods have long been used for the characterization of complex coacervate-based materials, it remains a challenge to predict the dynamics for a new system of materials. Furthermore, most work reports only qualitative trends exist as to how parameters such as charge stoichiometry, ionic strength, and polymer chain length impact self-assembly and material dynamics, and there is little information on the effects of polymer architecture or the organization of charges within a polymer. We seek to link thermodynamic studies of coacervation phase behavior with material dynamics through a carefully-controlled, systematic study of coacervate linear viscoelasticity for different polymer chemistries. We couple various methods of characterizing the dynamics of polymer-based complex coacervates, including the time-salt superposition methods developed first by Spruijt and coworkers to establish a more mechanistic strategy for comparing the material dynamics and linear viscoelasticity of different systems. Acknowledgment is made to the Donors of the American Chemical Society Petroleum Research Fund for support of this research.

  4. Dynamic mechanical characterization with respect to temperature, humidity, frequency and strain in mPOFs made of different materials

    DEFF Research Database (Denmark)

    Leal-Junior, A.; Frizera, A.; Pontes, M. J.

    2018-01-01

    This paper presents a dynamic mechanical analysis (DMA) of polymer optical fibers (POFs) to obtain their Young modulus with respect to the variation of strain, temperature, humidity and frequency. The POFs tested are made of polymethyl methacrylate (PMMA), Topas grade 5013, Zeonex 480R...... and Polycarbonate (PC). In addition, a step index POF with a core composed of Topas 5013 and cladding of Zeonex 480R is also analyzed. Results show a tradeoffbetween the different fibers for different applications, where the Zeonex fiber shows the lowest Young modulus among the ones tested, which makes it suitable...... for high-sensitivity strain sensing applications. In addition, the fibers with Topas in their composition presented low temperature and humidity sensitivity, whereas PMMA fibers presented the highest Young modulus variation with different frequencies. The results presented here provide guidelines...

  5. Different developmental trajectories across feature types support a dynamic field model of visual working memory development.

    Science.gov (United States)

    Simmering, Vanessa R; Miller, Hilary E; Bohache, Kevin

    2015-05-01

    Research on visual working memory has focused on characterizing the nature of capacity limits as "slots" or "resources" based almost exclusively on adults' performance with little consideration for developmental change. Here we argue that understanding how visual working memory develops can shed new light onto the nature of representations. We present an alternative model, the Dynamic Field Theory (DFT), which can capture effects that have been previously attributed either to "slot" or "resource" explanations. The DFT includes a specific developmental mechanism to account for improvements in both resolution and capacity of visual working memory throughout childhood. Here we show how development in the DFT can account for different capacity estimates across feature types (i.e., color and shape). The current paper tests this account by comparing children's (3, 5, and 7 years of age) performance across different feature types. Results showed that capacity for colors increased faster over development than capacity for shapes. A second experiment confirmed this difference across feature types within subjects, but also showed that the difference can be attenuated by testing memory for less familiar colors. Model simulations demonstrate how developmental changes in connectivity within the model-purportedly arising through experience-can capture differences across feature types.

  6. Dynamic contrast-enhanced magnetic resonance imaging: a non-invasive method to evaluate significant differences between malignant and normal tissue

    International Nuclear Information System (INIS)

    Rudisch, Ansgar; Kremser, Christian; Judmaier, Werner; Zunterer, Hildegard; DeVries, Alexander F.

    2005-01-01

    Purpose: An ever recurring challenge in diagnostic radiology is the differentiation between non-malignant and malignant tissue. Based on evidence that microcirculation of normal, non-malignant tissue differs from that of malignant tissue, the goal of this study was to assess the reliability of dynamic contrast-enhanced Magnetic Resonance Imaging (dcMRI) for differentiating these two entities. Materials and methods: DcMRI data of rectum carcinoma and gluteus maximus muscles were acquired in 41 patients. Using an fast T1-mapping sequence on a 1.5-T whole body scanner, T1-maps were dynamically retrieved before, during and after constant rate i.v. infusion of a contrast medium (CM). On the basis of the acquired data sets, PI-values were calculated on a pixel-by-pixel basis. The relevance of spatial heterogeneities of microcirculation was investigated by relative frequency histograms of the PI-values. Results: A statistically significant difference between malignant and normal tissue was found for the mean PI-value (P < 0.001; 8.95 ml/min/100 g ± 2.45 versus 3.56 ml/min/100 g ± 1.20). Additionally relative frequency distributions of PI-values with equal class intervals of 2.5 ml/min/100 g revealed significant differences between the histograms of muscles and rectum carcinoma. Conclusion: We could show that microcirculation differences between malignant and normal, non-malignant tissue can be reliably assessed by non-invasive dcMRI. Therefore, dcMRI holds great promise in the aid of cancer assessment, especially in patients where biopsy is contraindicated

  7. Coarse-graining complex dynamics

    DEFF Research Database (Denmark)

    Sibani, Paolo

    2013-01-01

    Continuous Time Random Walks (CTRW) are widely used to coarse-grain the evolution of systems jumping from a metastable sub-set of their configuration space, or trap, to another via rare intermittent events. The multi-scaled behavior typical of complex dynamics is provided by a fat...... macroscopic variables all produce identical long time relaxation behaviors. Hence, CTRW shed no light on the link between microscopic and macroscopic dynamics. We then highlight how a more recent approach, Record Dynamics (RD) provides a viable alternative, based on a very different set of physical ideas......: while CTRW make use of a renewal process involving identical traps of infinite size, RD embodies a dynamical entrenchment into a hierarchy of traps which are finite in size and possess different degrees of meta-stability. We show in particular how RD produces the stretched exponential, power...

  8. Soil and plant nitrogen dynamics of a tomato crop under different fertilization strategies

    DEFF Research Database (Denmark)

    Doltra, Jordi; Muñoz, P; Antón, A

    2010-01-01

    (TM) kg N ha-1. The N contents of plants sampled on three occasions during the growing period and those of marketable fruits were also analyzed. Total marketable yield was determined at the end of the harvest period. The EU-Rotate_N model was used to predict the effects of the applied treatments......A field experiment was conducted in 2007 to investigate the effects of the N fertilizer source on the soil and plant N dynamics of a tomato crop grown in a sandy loam soil. The fertilization treatments were: mineral N-fertilization applied by fertigation (TM); organic N-fertilization (TO....... The model was calibrated using data from a previous experiment. No differences between treatments were observed with respect to yield or N content in marketable fruits. The amount of N left in the field at the end of the cropping period was significantly lower in TO than in TC and TM. Simulated plant growth...

  9. 18th International Conference on Difference Equations and Applications

    CERN Document Server

    Cushing, Jim; Elaydi, Saber; Pinto, Alberto

    2016-01-01

    These proceedings of the 18th International Conference on Difference Equations and Applications cover a number of different aspects of difference equations and discrete dynamical systems, as well as the interplay between difference equations and dynamical systems. The conference was organized by the Department of Mathematics at the Universitat Autònoma de Barcelona (UAB) under the auspices of the International Society of Difference Equations (ISDE) and held in Barcelona (Catalonia, Spain) in July 2012. Its purpose was to bring together experts and novices in these fields to discuss the latest developments. The book gathers contributions in the field of combinatorial and topological dynamics, complex dynamics, applications of difference equations to biology, chaotic linear dynamics, economic dynamics and control and asymptotic behavior, and periodicity of difference equations. As such it is of interest to researchers and scientists engaged in the theory and applications of difference equations and discrete dy...

  10. Monitoring intra-annual dynamics of wood formation with microcores and dendrometers in Picea abies at two different altitudes.

    Science.gov (United States)

    Cocozza, Claudia; Palombo, Caterina; Tognetti, Roberto; La Porta, Nicola; Anichini, Monica; Giovannelli, Alessio; Emiliani, Giovanni

    2016-07-01

    Seasonal analyses of cambial cell production and day-by-day stem radial increment can help to elucidate how climate modulates wood formation in conifers. Intra-annual dynamics of wood formation were determined with microcores and dendrometers and related to climatic signals in Norway spruce (Picea abies (L.) Karst.). The seasonal dynamics of these processes were observed at two sites of different altitude, Savignano (650 m a.s.l.) and Lavazè (1800 m a.s.l.) in the Italian Alps. Seasonal dynamics of cambial activity were found to be site specific, indicating that the phenology of cambial cell production is highly variable and plastic with altitude. There was a site-specific trend in the number of cells in the wall thickening phase, with the maximum cell production in early July (DOY 186) at Savignano and in mid-July (DOY 200) at Lavazè. The formation of mature cells showed similar trends at the two sites, although different numbers of cells and timing of cell differentiation were visible in the model shapes; at the end of ring formation in 2010, the number of cells was four times higher at Savignano (106.5 cells) than at Lavazè (26.5 cells). At low altitudes, microcores and dendrometers described the radial growth patterns comparably, though the dendrometer function underlined the higher upper asymptote of maximum growth in comparison with the cell production function. In contrast, at high altitude, these functions exhibited different trends. The best model was obtained by fitting functions of the Gompertz model to the experimental data. By combining radial growth and cambial activity indices we defined a model system able to synchronize these processes. Processes of adaptation of the pattern of xylogenesis occurred, enabling P. abies to occupy sites with contrasting climatic conditions. The use of daily climatic variables in combination with plant functional traits obtained by sensors and/or destructive sampling could provide a suitable tool to better

  11. Dynamics of the population quantity of Juglans mandshurica Maxim. in different habitats in Xinjiang, China

    International Nuclear Information System (INIS)

    Yang, Y.; Li, J.; Zhang, W.

    2015-01-01

    Transects were arranged on the shady and sunny slopes, as well as at different elevations of the main, eastern, central, and western gullies in the Wild Walnut Nature Reserve in Xinjiang, China to survey a large sample of Juglans mandshurica. The structures of height class and diameter at breast height (DBH) class were used to represent age structure to compare and analyze the dynamics of the population quantity of J. mandshurica in different habitats. Results showed that J. mandshurica population comprises numerous young seedlings, which develop into young plants with a high death rate. The number of adult plants is stable. J. mandshurica population is r-strategists in the young stage, and k-strategists supplemented by r-strategists in the juvenile and subsequent stages. The structures of height class and DBH class fluctuate at different slope aspects and elevations. The growth of young seedlings into adult plants is discontinuous. Tree height and DBH are relatively uniform in the same age class, and the coefficient of variation is independent of slope aspect and elevation. The maximum numbers of age classes in J. mandshurica population with different height and DBH classes differ at three elevations. Low- and medium-age classes are dominant in all situations. That is, population is mainly composed of juvenile and adult trees, and age structure is classified as a growth type. Without strong external interference, J. mandshurica population will maintain its superior position in the community. (author)

  12. Dynamic calculations of a PWR - reactor building for different soil parameters for the safe shutdown earthquake and explosion pressure wave load cases

    International Nuclear Information System (INIS)

    Brandt, K.; Krutzik, N.; Kaiser, A.

    1982-01-01

    For different dynamic soil properties and soil dampings - ranging from very soft to very rigid soil parameters - time histoires of displacements and accelerations as well as response spectra are calculated for several floors for the reactor building of a nuclear power plant using a finite element shell model. As regards the loadcase safety earthquake the computations are carried out for four different soil properties, and the response spectra of different floors are compared. In the loadcase exterior explosion, results for three different soils are obtained. All results are discussed and explained extensively. (Author) [pt

  13. Differing Time of Onset of Concurrent TMS-fMRI during Associative Memory Encoding: A Measure of Dynamic Connectivity

    Directory of Open Access Journals (Sweden)

    Colin Hawco

    2017-08-01

    Full Text Available There has been a distinct shift in neuroimaging from localization of function into a more network based approach focused on connectivity. While fMRI has proven very fruitful for this, the hemodynamic signal is inherently slow which limits the temporal resolution of fMRI-only connectivity measures. The brain, however, works on a time scale of milliseconds. This study utilized concurrent transcranial magnetic stimulation (TMS-fMRI in a novel way to obtain measures of dynamic connectivity by measuring changes in fMRI signal amplitude in regions distal to the site of stimulation following differing TMS onset times. Seventeen healthy subjects completed an associative memory encoding task known to involve the DLPFC, viewing pairs of objects which could be semantically related or unrelated. Three pulses of 10 Hz repetitive TMS were applied over the left DLPFC starting either at 200, 600, or 1000 ms after stimulus onset. Associations for related pairs were better remembered than unrelated pairs in a post-scan cued recall test. Differences in neural activity were assessed across different TMS onsets, separately for related and unrelated pairs. Time specific TMS effects were observed in several regions, including those associated with higher-level processing (lateral frontal, anterior cingulate, visual areas (occipital, and regions involved in semantic processing (e.g., left mid-temporal and medial frontal. Activity in the frontal cortex was decreased at 200 ms post-stimulus for unrelated pairs, and 1000 ms post-stimulus for related pairs. This suggests differences in the timing across conditions in which the DLFPC interacts with other PFC regions, consistent with the notion that the DLPFC is facilitating extended semantic processing for related items. This study demonstrates that time-varying TMS onset inside the MRI can be used to reliably measure fast dynamic connectivity with a temporal resolution in the hundreds of milliseconds.

  14. Effect of Difference-frequency Forces on the Dynamics of a Semi-submersible Type FVAWT in Misaligned Wave-wind Condition

    DEFF Research Database (Denmark)

    Wang, Kai; Cheng, Zhengshun; Moan, Torgeir

    2015-01-01

    With increasing interests in the development of offshore floating vertical axis wind turbines (FVAWTs), a large amount of studies on the FVAWTs have been conducted. This paper focuses on evaluating the effect of second-order difference-frequency force on the dynamics of a 5 MW FVAWT in misaligned...... wave-wind condition. The studied FVAWT is composed of a 5 MW Darrieus rotor, a semi-submersible floater and a catenary mooring system. Fully coupled nonlinear time domain simulations were conducted using the state-of-art code Simo- Riflex-DMS. Several misaligned wave-wind conditions were selected...... to investigate the global dynamic responses of the FVAWT, such as the platform motions, structural responses and mooring line tensions. It has been found that the wave-wind misalignment does not significantly affect the mean values of the global responses since the global responses are primarily wind...

  15. Modal and Dynamic Analysis of a Vehicle with Kinetic Dynamic Suspension System

    Directory of Open Access Journals (Sweden)

    Bangji Zhang

    2016-01-01

    Full Text Available A novel kinetic dynamic suspension (KDS system is presented for the cooperative control of the roll and warp motion modes of off-road vehicles. The proposed KDS system consists of two hydraulic cylinders acting on the antiroll bars. Hence, the antiroll bars are not completely replaced by the hydraulic system, but both systems are installed. In this paper, the vibration analysis in terms of natural frequencies of different motion modes in frequency domain for an off-road vehicle equipped with different configurable suspension systems is studied by using the modal analysis method. The dynamic responses of the vehicle with different configurable suspension systems are investigated under different road excitations and maneuvers. The results of the modal and dynamic analysis prove that the KDS system can reduce the roll and articulation motions of the off-road vehicle without adding extra bounce stiffness and deteriorating the ride comfort. Furthermore, the roll stiffness is increased and the warp stiffness is decreased by the KDS system, which could significantly enhance handing performance and off-road capability.

  16. Static and dynamic analysis of high-rise building with consideration of two different values of subsoil stiffness coefficients

    Directory of Open Access Journals (Sweden)

    Ivankova Olga

    2017-01-01

    Full Text Available This paper deals with the analysis of 21-storeyed cast in-situ reinforced concrete high-rise building. Two different 3D models were created, because of two considered values of subsoil stiffness coefficient -fixed structure (alt. 1 and the structure supported by elastic soil (alt. 2. For both alternatives of foundation of structure, required analyses (static and dynamic were done and obtained results were compared in this paper. Short description of the structure, applied loads and other input parameters are also mentioned here. The main purpose of this analysis was to provide more information to planning engineers about the behaviour of structure exposed the wind load or seismic load when different soil conditions were considered.

  17. Differences in perfusion parameters between upper and lower lumbar vertebral segments with dynamic contrast-enhanced MRI (DCE MRI)

    International Nuclear Information System (INIS)

    Savvopoulou, Vasiliki; Vlahos, Lampros; Moulopoulos, Lia Angela; Maris, Thomas G.

    2008-01-01

    To investigate the influence of age, sex and spinal level on perfusion parameters of normal lumbar bone marrow with dynamic contrast-enhanced MRI (DCE MRI). Sixty-seven subjects referred for evaluation of low back pain or sciatica underwent DCE MRI of the lumbar spine. After subtraction of dynamic images, a region of interest (ROI) was placed on each lumbar vertebral body of all subjects, and time intensity curves were generated. Consequently, perfusion parameters were calculated. Statistical analysis was performed to search for perfusion differences among lumbar vertebrae and in relation to age and sex. Upper (L1, L2) and lower (L3, L4, L5) vertebrae showed significant differences in perfusion parameters (p<0.05). Vertebrae of subjects younger than 50 years showed significantly higher perfusion compared to vertebrae of older ones (p<0.05). Vertebrae of females demonstrated significantly increased perfusion compared to those of males of corresponding age (p<0.05). All perfusion parameters, except for washout (WOUT), showed a mild linear correlation with age. Time to maximum slope (TMSP) and time to peak (TTPK) showed the same correlation with sex (0.22< r<0.32, p<0.05). Our results indicate increased perfusion of the upper compared to the lower lumbar spine, of younger compared to older subjects and of females compared to males. (orig.)

  18. Differences in perfusion parameters between upper and lower lumbar vertebral segments with dynamic contrast-enhanced MRI (DCE MRI)

    Energy Technology Data Exchange (ETDEWEB)

    Savvopoulou, Vasiliki; Vlahos, Lampros; Moulopoulos, Lia Angela [University of Athens, Areteion Hospital, Department of Radiology, Medical School, Athens (Greece); Maris, Thomas G. [University of Crete, Deparment of Medical Physics, Faculty of Medicine, Heraklion (Greece)

    2008-09-15

    To investigate the influence of age, sex and spinal level on perfusion parameters of normal lumbar bone marrow with dynamic contrast-enhanced MRI (DCE MRI). Sixty-seven subjects referred for evaluation of low back pain or sciatica underwent DCE MRI of the lumbar spine. After subtraction of dynamic images, a region of interest (ROI) was placed on each lumbar vertebral body of all subjects, and time intensity curves were generated. Consequently, perfusion parameters were calculated. Statistical analysis was performed to search for perfusion differences among lumbar vertebrae and in relation to age and sex. Upper (L1, L2) and lower (L3, L4, L5) vertebrae showed significant differences in perfusion parameters (p<0.05). Vertebrae of subjects younger than 50 years showed significantly higher perfusion compared to vertebrae of older ones (p<0.05). Vertebrae of females demonstrated significantly increased perfusion compared to those of males of corresponding age (p<0.05). All perfusion parameters, except for washout (WOUT), showed a mild linear correlation with age. Time to maximum slope (TMSP) and time to peak (TTPK) showed the same correlation with sex (0.22

  19. Trading of dynamic interaural time and level difference cues and its effect on the auditory motion-onset response measured with electroencephalography.

    Science.gov (United States)

    Altmann, Christian F; Ueda, Ryuhei; Bucher, Benoit; Furukawa, Shigeto; Ono, Kentaro; Kashino, Makio; Mima, Tatsuya; Fukuyama, Hidenao

    2017-10-01

    Interaural time (ITD) and level differences (ILD) constitute the two main cues for sound localization in the horizontal plane. Despite extensive research in animal models and humans, the mechanism of how these two cues are integrated into a unified percept is still far from clear. In this study, our aim was to test with human electroencephalography (EEG) whether integration of dynamic ITD and ILD cues is reflected in the so-called motion-onset response (MOR), an evoked potential elicited by moving sound sources. To this end, ITD and ILD trajectories were determined individually by cue trading psychophysics. We then measured EEG while subjects were presented with either static click-trains or click-trains that contained a dynamic portion at the end. The dynamic part was created by combining ITD with ILD either congruently to elicit the percept of a right/leftward moving sound, or incongruently to elicit the percept of a static sound. In two experiments that differed in the method to derive individual dynamic cue trading stimuli, we observed an MOR with at least a change-N1 (cN1) component for both the congruent and incongruent conditions at about 160-190 ms after motion-onset. A significant change-P2 (cP2) component for both the congruent and incongruent ITD/ILD combination was found only in the second experiment peaking at about 250 ms after motion onset. In sum, this study shows that a sound which - by a combination of counter-balanced ITD and ILD cues - induces a static percept can still elicit a motion-onset response, indicative of independent ITD and ILD processing at the level of the MOR - a component that has been proposed to be, at least partly, generated in non-primary auditory cortex. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Conceptualizing Teacher Identity as a Complex Dynamic System: The Inner Dynamics of Transformations during a Practicum

    Science.gov (United States)

    Henry, Alastair

    2016-01-01

    Currently, the inner dynamics of teacher identity transformations remain a "black box." Conceptualizing preservice teacher identity as a complex dynamic system, and the notion of "being someone who teaches" in dialogical terms as involving shifts between different teacher voices, the study investigates the dynamical processes…

  1. The dynamics of transmission and the dynamics of networks.

    Science.gov (United States)

    Farine, Damien

    2017-05-01

    A toy example depicted here highlighting the results of a study in this issue of the Journal of Animal Ecology that investigates the impact of network dynamics on potential disease outbreaks. Infections (stars) that spread by contact only (left) reduce the predicted outbreak size compared to situations where individuals can become infected by moving through areas that previously contained infected individuals (right). This is potentially important in species where individuals, or in this case groups, have overlapping ranges (as depicted on the top right). Incorporating network dynamics that maintain information about the ordering of contacts (central blocks; including the ordering of spatial overlap as noted by the arrows that highlight the blue group arriving after the red group in top-right of the figure) is important for capturing how a disease might not have the opportunity to spread to all individuals. By contrast, a static or 'average' network (lower blocks) does not capture any of these dynamics. Interestingly, although static networks generally predict larger outbreak sizes, the authors find that in cases when transmission probability is low, this prediction can switch as a result of changes in the estimated intensity of contacts among individuals. [Colour figure can be viewed at wileyonlinelibrary.com]. Springer, A., Kappeler, P.M. & Nunn, C.L. (2017) Dynamic vs. static social networks in models of parasite transmission: Predicting Cryptosporidium spread in wild lemurs. Journal of Animal Ecology, 86, 419-433. The spread of disease or information through networks can be affected by several factors. Whether and how these factors are accounted for can fundamentally change the predicted impact of a spreading epidemic. Springer, Kappeler & Nunn () investigate the role of different modes of transmission and network dynamics on the predicted size of a disease outbreak across several groups of Verreaux's sifakas, a group-living species of lemur. While some factors

  2. Double dynamic scaling in human communication dynamics

    Science.gov (United States)

    Wang, Shengfeng; Feng, Xin; Wu, Ye; Xiao, Jinhua

    2017-05-01

    In the last decades, human behavior has been deeply understanding owing to the huge quantities data of human behavior available for study. The main finding in human dynamics shows that temporal processes consist of high-activity bursty intervals alternating with long low-activity periods. A model, assuming the initiator of bursty follow a Poisson process, is widely used in the modeling of human behavior. Here, we provide further evidence for the hypothesis that different bursty intervals are independent. Furthermore, we introduce a special threshold to quantitatively distinguish the time scales of complex dynamics based on the hypothesis. Our results suggest that human communication behavior is a composite process of double dynamics with midrange memory length. The method for calculating memory length would enhance the performance of many sequence-dependent systems, such as server operation and topic identification.

  3. Dynamic sensory description of Rioja Alavesa red wines made by different winemaking practices by using Temporal Dominance of Sensations.

    Science.gov (United States)

    Etaio, Iñaki; Meillon, Sophie; Pérez-Elortondo, Francisco J; Schlich, Pascal

    2016-08-01

    Although sensory description of wines in scientific literature is very large, there is an evident lack of studies describing wines from a dynamic approach. The objective of this study was to describe the evolution of the sensations perceived in red wines from Rioja Alavesa by using Temporal Dominance of Sensations (TDS) and also to compare wines made with the two winemaking procedures used in Rioja Alavesa: carbonic maceration (CM) and destemming (DS). Ten sensory attributes were evaluated in eight wines (four CM and four DS wines) in triplicate by a panel of 16 trained assessors. Red/black berry and woody aromas were dominant firstly, whereas heat, astringent, bitter and pungent sensations were dominant later. CM wines showed higher dominance for woody, spicy, pungent and acid sensations and lower dominance for red/black berry aroma and astringency than DS wines. This study is the first to describe Rioja wines from a dynamic approach and it also provides information about the dynamic sensory differences between wines made by CM or by DS. In this sense, this work shows the usefulness of TDS to describe and differentiate wines and to provide additional information to the conventional static descriptive analysis. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

  4. The Dynamical Invariant of Open Quantum System

    OpenAIRE

    Wu, S. L.; Zhang, X. Y.; Yi, X. X.

    2015-01-01

    The dynamical invariant, whose expectation value is constant, is generalized to open quantum system. The evolution equation of dynamical invariant (the dynamical invariant condition) is presented for Markovian dynamics. Different with the dynamical invariant for the closed quantum system, the evolution of the dynamical invariant for the open quantum system is no longer unitary, and the eigenvalues of it are time-dependent. Since any hermitian operator fulfilling dynamical invariant condition ...

  5. Dynamic Range Across Music Genres and the Perception of Dynamic Compression in Hearing-Impaired Listeners

    Directory of Open Access Journals (Sweden)

    Martin Kirchberger

    2016-02-01

    Full Text Available Dynamic range compression serves different purposes in the music and hearing-aid industries. In the music industry, it is used to make music louder and more attractive to normal-hearing listeners. In the hearing-aid industry, it is used to map the variable dynamic range of acoustic signals to the reduced dynamic range of hearing-impaired listeners. Hence, hearing-aided listeners will typically receive a dual dose of compression when listening to recorded music. The present study involved an acoustic analysis of dynamic range across a cross section of recorded music as well as a perceptual study comparing the efficacy of different compression schemes. The acoustic analysis revealed that the dynamic range of samples from popular genres, such as rock or rap, was generally smaller than the dynamic range of samples from classical genres, such as opera and orchestra. By comparison, the dynamic range of speech, based on recordings of monologues in quiet, was larger than the dynamic range of all music genres tested. The perceptual study compared the effect of the prescription rule NAL-NL2 with a semicompressive and a linear scheme. Music subjected to linear processing had the highest ratings for dynamics and quality, followed by the semicompressive and the NAL-NL2 setting. These findings advise against NAL-NL2 as a prescription rule for recorded music and recommend linear settings.

  6. Dynamic Range Across Music Genres and the Perception of Dynamic Compression in Hearing-Impaired Listeners

    Science.gov (United States)

    Kirchberger, Martin

    2016-01-01

    Dynamic range compression serves different purposes in the music and hearing-aid industries. In the music industry, it is used to make music louder and more attractive to normal-hearing listeners. In the hearing-aid industry, it is used to map the variable dynamic range of acoustic signals to the reduced dynamic range of hearing-impaired listeners. Hence, hearing-aided listeners will typically receive a dual dose of compression when listening to recorded music. The present study involved an acoustic analysis of dynamic range across a cross section of recorded music as well as a perceptual study comparing the efficacy of different compression schemes. The acoustic analysis revealed that the dynamic range of samples from popular genres, such as rock or rap, was generally smaller than the dynamic range of samples from classical genres, such as opera and orchestra. By comparison, the dynamic range of speech, based on recordings of monologues in quiet, was larger than the dynamic range of all music genres tested. The perceptual study compared the effect of the prescription rule NAL-NL2 with a semicompressive and a linear scheme. Music subjected to linear processing had the highest ratings for dynamics and quality, followed by the semicompressive and the NAL-NL2 setting. These findings advise against NAL-NL2 as a prescription rule for recorded music and recommend linear settings. PMID:26868955

  7. Dynamic Range Across Music Genres and the Perception of Dynamic Compression in Hearing-Impaired Listeners.

    Science.gov (United States)

    Kirchberger, Martin; Russo, Frank A

    2016-02-10

    Dynamic range compression serves different purposes in the music and hearing-aid industries. In the music industry, it is used to make music louder and more attractive to normal-hearing listeners. In the hearing-aid industry, it is used to map the variable dynamic range of acoustic signals to the reduced dynamic range of hearing-impaired listeners. Hence, hearing-aided listeners will typically receive a dual dose of compression when listening to recorded music. The present study involved an acoustic analysis of dynamic range across a cross section of recorded music as well as a perceptual study comparing the efficacy of different compression schemes. The acoustic analysis revealed that the dynamic range of samples from popular genres, such as rock or rap, was generally smaller than the dynamic range of samples from classical genres, such as opera and orchestra. By comparison, the dynamic range of speech, based on recordings of monologues in quiet, was larger than the dynamic range of all music genres tested. The perceptual study compared the effect of the prescription rule NAL-NL2 with a semicompressive and a linear scheme. Music subjected to linear processing had the highest ratings for dynamics and quality, followed by the semicompressive and the NAL-NL2 setting. These findings advise against NAL-NL2 as a prescription rule for recorded music and recommend linear settings. © The Author(s) 2016.

  8. Infant emotion regulation: relations to bedtime emotional availability, attachment security, and temperament.

    Science.gov (United States)

    Kim, Bo-Ram; Stifter, Cynthia A; Philbrook, Lauren E; Teti, Douglas M

    2014-11-01

    The present study examines the influences of mothers' emotional availability toward their infants during bedtime, infant attachment security, and interactions between bedtime parenting and attachment with infant temperamental negative affectivity, on infants' emotion regulation strategy use at 12 and 18 months. Infants' emotion regulation strategies were assessed during a frustration task that required infants to regulate their emotions in the absence of parental support. Whereas emotional availability was not directly related to infants' emotion regulation strategies, infant attachment security had direct relations with infants' orienting toward the environment and tension reduction behaviors. Both maternal emotional availability and security of the mother-infant attachment relationship interacted with infant temperamental negative affectivity to predict two strategies that were less adaptive in regulating frustration. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. First selection, then influence : Developmental differences in friendship dynamics regarding academic achievement

    NARCIS (Netherlands)

    Gremmen, Mariola Claudia; Dijkstra, Jan Kornelis; Steglich, Christian; Veenstra, René

    This study concerns peer selection and influence dynamics in early adolescents' friendships regarding academic achievement. Using longitudinal social network analysis (RSiena), both selection and influence processes were investigated for students' average grades and their cluster-specific grades

  10. Social strain, couple dynamics and gender differences in gambling problems: evidence from Chinese married couples.

    Science.gov (United States)

    Cheung, Nicole W T

    2015-02-01

    Knowledge of the influence of couple dynamics on gender differences in gambling behavior remains meager. Building on general strain theory from the sociology of deviance and stress crossover theory from social psychology, we argue that the strain encountered by one partner in a social setting may affect his or her spouse. For instance, the wife of a man under more social strain may experience more strain in turn and thus be at a higher risk of developing disordered gambling than the wife of a man under less social strain. Using community survey data of 1620 Chinese married couples, we performed multilevel dyad analyses to address social strain and couple dynamics, in addition to their roles as predictors of gambling behavior in both spouses. This was a community survey of Hong Kong and therefore was not representative of China. Based on the DSM-IV screen, the rates of probable problem gambling and pathological gambling among male partners (12.8% vs. 2.5%) were twice those among female partners (5.2% vs. 0.3%). We also found that the social strain experienced by a male partner significantly predicted both his and his wife's likelihood of developing gambling problems. Although a female partner's exposure to social strain was a significant correlate of her gambling problem, it had no significant association with her husband's gambling behavior. These results suggest that the cross-spouse transference of social strain may be a gendered process. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Dynamic changes in the secondary structure of ECE-1 and XCE account for their different substrate specificities

    Directory of Open Access Journals (Sweden)

    Ul-Haq Zaheer

    2012-11-01

    Full Text Available Abstract Background X-converting enzyme (XCE involved in nervous control of respiration, is a member of the M13 family of zinc peptidases, for which no natural substrate has been identified yet. In contrast, it’s well characterized homologue endothelin-converting enzyme-1 (ECE-1 showed broad substrate specificity and acts as endopeptidase as well as dipeptidase. To explore the structural differences between XCE and ECE-1, homology model of XCE was built using the complex structure of ECE-1 with phosphoramidon (pdb-id: 3DWB as template. Phosphoramidon was docked into the binding site of XCE whereas phosphate oxygen of the inhibitor was used as water molecule to design the apo forms of both enzymes. Molecular dynamics simulation of both enzymes was performed to analyze the dynamic nature of their active site residues in the absence and presence of the inhibitor. Results Homology model of XCE explained the role of non-conserved residues of its S2’ subsite. Molecular dynamics (MD simulations identified the flexible transitions of F149/I150, N566/N571, W714/W719, and R145/R723 residues of ECE-1/XCE for the strong binding of the inhibitor. Secondary structure calculations using DSSP method reveals the folding of R145/R723 residue of ECE-1/XCE into β-sheet structure while unfolding of the S2’ subsite residues in aECE-1 and sustained compact folding of that of aXCE. The results evaluated are in good agreement with available experimental data, thus providing detailed molecular models which can explain the structural and specificities differences between both zinc peptidases. Conclusions Secondary structure changes of both enzymes during the simulation time revealed the importance of β-sheet structure of R145/R723 for its binding with the terminal carboxylate group of the inhibitor. Unfolding of the α-helix comprising the S2’ subsite residues in aECE-1 correlate well with its endopeptidase activity while their compact folding in aXCE may

  12. Classification of Dynamic Vehicle Routing Systems

    DEFF Research Database (Denmark)

    Larsen, Allan; Madsen, Oli B.G.; Solomon, Marius M.

    2007-01-01

    This chapter discusses important characteristics seen within dynamic vehicle routing problems. We discuss the differences between the traditional static vehicle routing problems and its dynamic counterparts. We give an in-depth introduction to the degree of dynamism measure which can be used to c...

  13. Seasonal differences in extinction and colonization drive occupancy dynamics of an imperilled amphibian.

    Directory of Open Access Journals (Sweden)

    Lea A Randall

    Full Text Available A detailed understanding of the population dynamics of many amphibian species is lacking despite concerns about declining amphibian biodiversity and abundance. This paper explores temporal patterns of occupancy and underlying extinction and colonization dynamics in a regionally imperiled amphibian species, the Northern leopard frog (Lithobates pipiens in Alberta. Our study contributes to elucidating regional occupancy dynamics at northern latitudes, where climate extremes likely have a profound effect on seasonal occupancy. The primary advantage of our study is its wide geographic scale (60,000 km2 and the use of repeat visual surveys each spring and summer from 2009-2013. We find that occupancy varied more dramatically between seasons than years, with low spring and higher summer occupancy. Between spring and summer, colonization was high and extinction low; inversely, colonization was low and extinction high over the winter. The dynamics of extinction and colonization are complex, making conservation management challenging. Our results reveal that Northern leopard frog occupancy was constant over the last five years and thus there is no evidence of decline or recovery within our study area. Changes to equilibrium occupancy are most sensitive to increasing colonization in the spring or declining extinction in the summer. Therefore, conservation and management efforts should target actions that are likely to increase spring colonization; this could be achieved through translocations or improving the quality or access to breeding habitat. Because summer occupancy is already high, it may be difficult to improve further. Nevertheless, summer extinction could be reduced by predator control, increasing water quality or hydroperiod of wetlands, or increasing the quality or quantity of summer habitat.

  14. Seasonal differences in extinction and colonization drive occupancy dynamics of an imperilled amphibian.

    Science.gov (United States)

    Randall, Lea A; Smith, Des H V; Jones, Breana L; Prescott, David R C; Moehrenschlager, Axel

    2015-01-01

    A detailed understanding of the population dynamics of many amphibian species is lacking despite concerns about declining amphibian biodiversity and abundance. This paper explores temporal patterns of occupancy and underlying extinction and colonization dynamics in a regionally imperiled amphibian species, the Northern leopard frog (Lithobates pipiens) in Alberta. Our study contributes to elucidating regional occupancy dynamics at northern latitudes, where climate extremes likely have a profound effect on seasonal occupancy. The primary advantage of our study is its wide geographic scale (60,000 km2) and the use of repeat visual surveys each spring and summer from 2009-2013. We find that occupancy varied more dramatically between seasons than years, with low spring and higher summer occupancy. Between spring and summer, colonization was high and extinction low; inversely, colonization was low and extinction high over the winter. The dynamics of extinction and colonization are complex, making conservation management challenging. Our results reveal that Northern leopard frog occupancy was constant over the last five years and thus there is no evidence of decline or recovery within our study area. Changes to equilibrium occupancy are most sensitive to increasing colonization in the spring or declining extinction in the summer. Therefore, conservation and management efforts should target actions that are likely to increase spring colonization; this could be achieved through translocations or improving the quality or access to breeding habitat. Because summer occupancy is already high, it may be difficult to improve further. Nevertheless, summer extinction could be reduced by predator control, increasing water quality or hydroperiod of wetlands, or increasing the quality or quantity of summer habitat.

  15. Dynamics of layered reinforced concrete beam on visco-elastic foundation with different resistances of concrete and reinforcement to tension and compression

    Science.gov (United States)

    Nemirovsky, Y. V.; Tikhonov, S. V.

    2018-03-01

    Originally, fundamentals of the theory of limit equilibrium and dynamic deformation of building metal and reinforced concrete structures were created by A. A. Gvozdev [1] and developed by his followers [4, 5, 6, 7, 11, 12]. Forming the basis for the calculation, the model of an ideal rigid-plastic material has enabled to determine in many cases the ultimate load bearing capacity and upper (kinematically possible) or lower (statically valid) values for a wide class of different structures with quite simple methods. At the same time, applied to concrete structures the most important property of concrete to significantly differently resist tension and compression was not taken into account [10]. This circumstance was considered in [3] for reinforced concrete beams under conditions of quasistatic loading. The deformation is often accompanied by resistance of the environment in construction practice [8, 9]. In [2], the dynamics of multi-layered concrete beams on visco-elastic foundation under the loadings of explosive type is considered. In this work we consider the case which is often encountered in practical applications when the loadings weakly change in time.

  16. Approximate but accurate quantum dynamics from the Mori formalism: I. Nonequilibrium dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Montoya-Castillo, Andrés, E-mail: am3720@columbia.edu; Reichman, David R., E-mail: drr2103@columbia.edu [Department of Chemistry, Columbia University, New York, New York 10027 (United States)

    2016-05-14

    We present a formalism that explicitly unifies the commonly used Nakajima-Zwanzig approach for reduced density matrix dynamics with the more versatile Mori theory in the context of nonequilibrium dynamics. Employing a Dyson-type expansion to circumvent the difficulty of projected dynamics, we obtain a self-consistent equation for the memory kernel which requires only knowledge of normally evolved auxiliary kernels. To illustrate the properties of the current approach, we focus on the spin-boson model and limit our attention to the use of a simple and inexpensive quasi-classical dynamics, given by the Ehrenfest method, for the calculation of the auxiliary kernels. For the first time, we provide a detailed analysis of the dependence of the properties of the memory kernels obtained via different projection operators, namely, the thermal (Redfield-type) and population based (NIBA-type) projection operators. We further elucidate the conditions that lead to short-lived memory kernels and the regions of parameter space to which this program is best suited. Via a thorough analysis of the different closures available for the auxiliary kernels and the convergence properties of the self-consistently extracted memory kernel, we identify the mechanisms whereby the current approach leads to a significant improvement over the direct usage of standard semi- and quasi-classical dynamics.

  17. Approximate but accurate quantum dynamics from the Mori formalism: I. Nonequilibrium dynamics

    International Nuclear Information System (INIS)

    Montoya-Castillo, Andrés; Reichman, David R.

    2016-01-01

    We present a formalism that explicitly unifies the commonly used Nakajima-Zwanzig approach for reduced density matrix dynamics with the more versatile Mori theory in the context of nonequilibrium dynamics. Employing a Dyson-type expansion to circumvent the difficulty of projected dynamics, we obtain a self-consistent equation for the memory kernel which requires only knowledge of normally evolved auxiliary kernels. To illustrate the properties of the current approach, we focus on the spin-boson model and limit our attention to the use of a simple and inexpensive quasi-classical dynamics, given by the Ehrenfest method, for the calculation of the auxiliary kernels. For the first time, we provide a detailed analysis of the dependence of the properties of the memory kernels obtained via different projection operators, namely, the thermal (Redfield-type) and population based (NIBA-type) projection operators. We further elucidate the conditions that lead to short-lived memory kernels and the regions of parameter space to which this program is best suited. Via a thorough analysis of the different closures available for the auxiliary kernels and the convergence properties of the self-consistently extracted memory kernel, we identify the mechanisms whereby the current approach leads to a significant improvement over the direct usage of standard semi- and quasi-classical dynamics.

  18. Influence of different technologies on dynamic pricing in district heating systems: Comparative case studies

    DEFF Research Database (Denmark)

    Dominkovic, Dominik Franjo; Wahlroos, Mikko; Syri, Sanna

    2018-01-01

    District heating markets are often dominated by monopolies in both Denmark and Finland. The same companies, often owned by local municipalities, are usually operating both supplying plants and district heating networks, while the pricing mechanisms are rigid, often agreed upon for one year...... in advance. The mentioned ownership scheme may cause problems, when one tries to gain a third party access in order to deliver excess heat or heat from cheaper heating plants. In this paper, two case studies were carried out to simulate the district heating systems based on dynamic pricing. Case studies were...... carried out for Sønderborg, Denmark and Espoo, Finland. The results showed that dynamic pricing fosters feeding the waste heat into the grid, as dynamic pricing reduced the total primary energy consumption and CO2 emissions in both case studies. In the best scenarios, the weighted average heat price...

  19. Household electricity consumers’ incentive to choose dynamic pricing under different taxation schemes

    DEFF Research Database (Denmark)

    Katz, Jonas; Kitzing, Lena; Schröder, Sascha Thorsten

    2018-01-01

    Dynamic pricing of retail electricity, as opposed to the widely applied average pricing, has often been proposed to enhance economic efficiency through demand response. The development of variable production from renewable energies and expectations about the installation of heat pumps and electric...

  20. Microstructure and annealing behavior of a modified 9Cr-1Mo steel after dynamic plastic deformation to different strains

    DEFF Research Database (Denmark)

    Zhang, Zhenbo; Mishin, Oleg; Tao, N.R.

    2015-01-01

    The microstructure, hardness and tensile properties of a modified 9Cr-1Mo steel processed by dynamic plastic deformation (DPD) to different strains (0.5 and 2.3) have been investigated in the as-deformed and annealed conditions. It is found that significant structural refinement and a high level...... in a loss of strength with only a small gain in ductility, coarsening combined with pronounced partial recrystallization enables a combination of appreciably increased ductility and comparatively high strength....

  1. An ocular biomechanic model for dynamic simulation of different eye movements.

    Science.gov (United States)

    Iskander, J; Hossny, M; Nahavandi, S; Del Porto, L

    2018-04-11

    Simulating and analysing eye movement is useful for assessing visual system contribution to discomfort with respect to body movements, especially in virtual environments where simulation sickness might occur. It can also be used in the design of eye prosthesis or humanoid robot eye. In this paper, we present two biomechanic ocular models that are easily integrated into the available musculoskeletal models. The model was previously used to simulate eye-head coordination. The models are used to simulate and analyse eye movements. The proposed models are based on physiological and kinematic properties of the human eye. They incorporate an eye-globe, orbital suspension tissues and six muscles with their connective tissues (pulleys). Pulleys were incorporated in rectus and inferior oblique muscles. The two proposed models are the passive pulleys and the active pulleys models. Dynamic simulations of different eye movements, including fixation, saccade and smooth pursuit, are performed to validate both models. The resultant force-length curves of the models were similar to the experimental data. The simulation results show that the proposed models are suitable to generate eye movement simulations with results comparable to other musculoskeletal models. The maximum kinematic root mean square error (RMSE) is 5.68° and 4.35° for the passive and active pulley models, respectively. The analysis of the muscle forces showed realistic muscle activation with increased muscle synergy in the active pulley model. Copyright © 2018 Elsevier Ltd. All rights reserved.

  2. Revisiting Gill's Circulation. Dynamic Response to Diabatic Heating of Different Horizontal Extents

    Science.gov (United States)

    Reboredo, B.; Bellon, G.

    2017-12-01

    The horizontal extent of diabatic heating associated with the MJO is thought to be crucial to its development, and the inability of GCMs to simulate the spatial, horizontal organization of clouds is considered a leading hypothesis to explain their limited capacity to simulate MJO events. This prevents the MJO large-circulation response from developing and feeding back on the development of clouds. We apply mid-tropospheric heating of different size in simple linear and non-linear models of the tropical atmosphere following Gill's seminal work on heat-induced tropical circulations. Results show that there is a scale for which the characteristic circulation {Γ c} for the vertical advection of moisture to produce the latent heat mean {Q} gives a rough estimate of the real world MJO scale. Overturning circulation flow rates above {Γ c} account for a circulation that transports more moisture than necessary to be maintained, and below {Γ c}, circulation would not transport enough moisture to maintain circulation. This dynamic scale might constrain the size of the spatially-organised convection necessary to the development of an MJO event. However, other effects are expected to modulate this scale, such as vertical advection of moisture anomalies, horizontal advection, evaporation, radiative heating, and sensible heat fluxes.

  3. Comparison of isotopic turnover dynamics in two different muscles of a coral reef fish during the settlement phase

    Directory of Open Access Journals (Sweden)

    Laura Gajdzik

    2015-09-01

    Full Text Available The temporal variation in carbon and nitrogen isotopic compositions (noted as δ13C and δ15N was investigated in the convict surgeonfish (Acanthurus triostegus at Moorea (French Polynesia. Over a period of 24 days, juveniles were reared in aquaria and subjected to two different feeding treatments: granules or algae. The dynamics of δ13C and δ15N in two muscles (the adductor mandibulae complex and the epaxial musculature having different functions were compared. At the end of experiments, a steady-state isotopic system in each muscle tissue was not reached. Especially for the algal treatment, we found different patterns of variation in isotopic compositions over time between the two muscles. The turnovers of δ13C showed opposite trends for each muscle but differences are mitigated by starvation and by the metamorphosis. Our study highlighted that the metabolism of coral reef fish may be subjected to catabolism or anabolism of non-protein precursors at settlement, inducing variation in isotopic compositions that are not linked to diet change.

  4. Early-stage changes in natural (13)C and (15)N abundance and nutrient dynamics during different litter decomposition.

    Science.gov (United States)

    Gautam, Mukesh Kumar; Lee, Kwang-Sik; Song, Byeong-Yeol; Lee, Dongho; Bong, Yeon-Sik

    2016-05-01

    Decomposition, nutrient, and isotopic (δ(13)C and δ(15)N) dynamics during 1 year were studied for leaf and twig litters of Pinus densiflora, Castanea crenata, Erigeron annuus, and Miscanthus sinensis growing on a highly weathered soil with constrained nutrient supply using litterbags in a cool temperate region of South Korea. Decay constant (k/year) ranged from 0.58 to 1.29/year, and mass loss ranged from 22.36 to 58.43 % among litter types. The results demonstrate that mass loss and nutrient dynamics of decomposing litter were influenced by the seasonality of mineralization and immobilization processes. In general, most nutrients exhibited alternate phases of rapid mineralization followed by gradual immobilization, except K, which was released throughout the field incubation. At the end of study, among all the nutrients only N and P showed net immobilization. Mobility of different nutrients from decomposing litter as the percentage of initial litter nutrient concentration was in the order of K > Mg > Ca > N ≈ P. The δ(13)C (0.32-6.70 ‰) and δ(15)N (0.74-3.90 ‰) values of residual litters showed nonlinear increase and decrease, respectively compared to initial isotopic values during decomposition. Litter of different functional types and chemical quality converged toward a conservative nutrient use strategy through mechanisms of slow decomposition and slow nutrient mobilization. Our results indicate that litter quality and season, are the most important regulators of litter decomposition in these forests. The results revealed significant relationships between litter decomposition rates and N, C:N ratio and P, and seasonality (temperature). These results and the convergence of different litters towards conservative nutrient use in these nutrient constrained ecosystems imply optimization of litter management because litter removal can have cascading effects on litter decomposition and nutrient availability in these systems.

  5. Towards methodical modelling: Differences between the structure and output dynamics of multiple conceptual models

    Science.gov (United States)

    Knoben, Wouter; Woods, Ross; Freer, Jim

    2016-04-01

    Conceptual hydrologic models consist of a certain arrangement of spatial and temporal dynamics consisting of stores, fluxes and transformation functions, depending on the modeller's choices and intended use. They have the advantages of being computationally efficient, being relatively easy model structures to reconfigure and having relatively low input data demands. This makes them well-suited for large-scale and large-sample hydrology, where appropriately representing the dominant hydrologic functions of a catchment is a main concern. Given these requirements, the number of parameters in the model cannot be too high, to avoid equifinality and identifiability issues. This limits the number and level of complexity of dominant hydrologic processes the model can represent. Specific purposes and places thus require a specific model and this has led to an abundance of conceptual hydrologic models. No structured overview of these models exists and there is no clear method to select appropriate model structures for different catchments. This study is a first step towards creating an overview of the elements that make up conceptual models, which may later assist a modeller in finding an appropriate model structure for a given catchment. To this end, this study brings together over 30 past and present conceptual models. The reviewed model structures are simply different configurations of three basic model elements (stores, fluxes and transformation functions), depending on the hydrologic processes the models are intended to represent. Differences also exist in the inner workings of the stores, fluxes and transformations, i.e. the mathematical formulations that describe each model element's intended behaviour. We investigate the hypothesis that different model structures can produce similar behavioural simulations. This can clarify the overview of model elements by grouping elements which are similar, which can improve model structure selection.

  6. Chunking Dynamics: Heteroclinics in Mind

    Directory of Open Access Journals (Sweden)

    Mikhail I Rabinovich

    2014-03-01

    Full Text Available Recent results of imaging technologies and nonlinear dynamics make possible to relate the structure and dynamics of functional brain networks to different mental tasks and to build theoretical models for the description and prediction of cognitive activity. Such models are nonlinear dynamical descriptions of the interaction of the core components –brain modes– participating in a specific mental function. The dynamical images of different mental processes depend on their temporal features. The dynamics of many cognitive functions are transient. They are often observed as a chain of sequentially changing metastable states. A stable heteroclinic channel consisting of chain of saddles -metastable states- connected by unstable separatrices is a mathematical image for robust transients. In this paper we focus on hierarchical chunking dynamics that can represent several forms of transient cognitive activity. Chunking is a dynamical phenomenon that nature uses to perform information processing of long sequences by dividing them in shorter information items. Chunking, for example, makes more efficient the use of short-term memory by breaking up long strings of information (like in language where one can see the separation of a novel on chapters, paragraphs, sentences and finally words. Chunking is important in many processes of perception, learning and cognition in humans and animals. Based on anatomical information about the hierarchical organization of functional brain networks, we proposed here a cognitive network architecture that hierarchically chunks and super-chunks switching sequences of metastable states produced by winnerless competitive heteroclinic dynamics.

  7. Fundamentals of gas dynamics

    CERN Document Server

    Babu, V

    2014-01-01

    Fundamentals of Gas Dynamics, Second Edition isa comprehensively updated new edition and now includes a chapter on the gas dynamics of steam. It covers the fundamental concepts and governing equations of different flows, and includes end of chapter exercises based on the practical applications. A number of useful tables on the thermodynamic properties of steam are also included.Fundamentals of Gas Dynamics, Second Edition begins with an introduction to compressible and incompressible flows before covering the fundamentals of one dimensional flows and normal shock wav

  8. [Mes differ by positioning: empirical testing of decentralized dynamics of the self].

    Science.gov (United States)

    Mizokami, Shinichi

    2013-10-01

    The present study empirically tested the conceptualization of the decentralized dynamics of the self proposed by Hermans & Kempen (1993), which they developed theoretically and from clinical cases, not from large samples of empirical data. They posited that worldviews and images of the self could vary by positioning even in the same individual, and denied that the ego was an omniscient entity that knew and controlled all aspects of the self (centralized ego). Study 1 tested their conceptualization empirically with 47 university students in an experimental group and 17 as a control group. The results showed that the scores on the Rosenberg's self-esteem scale and images of the Mes in the experimental group significantly varied by positioning, but those in the control group did not. Similar results were found in Study 2 with a sample of 120 university students. These results empirically supported the conceptualization of the decentralized dynamics of the self.

  9. Molecular dynamics simulations revealed structural differences among WRKY domain-DNA interaction in barley (Hordeum vulgare).

    Science.gov (United States)

    Pandey, Bharati; Grover, Abhinav; Sharma, Pradeep

    2018-02-12

    The WRKY transcription factors are a class of DNA-binding proteins involved in diverse plant processes play critical roles in response to abiotic and biotic stresses. Genome-wide divergence analysis of WRKY gene family in Hordeum vulgare provided a framework for molecular evolution and functional roles. So far, the crystal structure of WRKY from barley has not been resolved; moreover, knowledge of the three-dimensional structure of WRKY domain is pre-requisites for exploring the protein-DNA recognition mechanisms. Homology modelling based approach was used to generate structures for WRKY DNA binding domain (DBD) and its variants using AtWRKY1 as a template. Finally, the stability and conformational changes of the generated model in unbound and bound form was examined through atomistic molecular dynamics (MD) simulations for 100 ns time period. In this study, we investigated the comparative binding pattern of WRKY domain and its variants with W-box cis-regulatory element using molecular docking and dynamics (MD) simulations assays. The atomic insight into WRKY domain exhibited significant variation in the intermolecular hydrogen bonding pattern, leading to the structural anomalies in the variant type and differences in the DNA-binding specificities. Based on the MD analysis, residual contribution and interaction contour, wild-type WRKY (HvWRKY46) were found to interact with DNA through highly conserved heptapeptide in the pre- and post-MD simulated complexes, whereas heptapeptide interaction with DNA was missing in variants (I and II) in post-MD complexes. Consequently, through principal component analysis, wild-type WRKY was also found to be more stable by obscuring a reduced conformational space than the variant I (HvWRKY34). Lastly, high binding free energy for wild-type and variant II allowed us to conclude that wild-type WRKY-DNA complex was more stable relative to variants I. The results of our study revealed complete dynamic and structural information

  10. Influence of Different Three-Dimensional Open Porous Titanium Scaffold Designs on Human Osteoblasts Behavior in Static and Dynamic Cell Investigations

    Directory of Open Access Journals (Sweden)

    Jana Markhoff

    2015-08-01

    Full Text Available In the treatment of osseous defects micro-structured three-dimensional materials for bone replacement serve as leading structure for cell migration, proliferation and bone formation. The scaffold design and culture conditions are crucial for the limited diffusion distance of nutrients and oxygen. In static culture, decreased cell activity and irregular distribution occur within the scaffold. Dynamic conditions entail physical stimulation and constant medium perfusion imitating physiological nutrient supply and metabolite disposal. Therefore, we investigated the influence of different scaffold configurations and cultivation methods on human osteoblasts. Cells were seeded on three-dimensional porous Ti-6Al-4V scaffolds manufactured with selective laser melting (SLM or electron beam melting (EBM varying in porosity, pore size and basic structure (cubic, diagonal, pyramidal and cultured under static and dynamic conditions. Cell viability, migration and matrix production were examined via mitochondrial activity assay, fluorescence staining and ELISA. All scaffolds showed an increasing cell activity and matrix production under static conditions over time. Expectations about the dynamic culture were only partially fulfilled, since it enabled proliferation alike the static one and enhanced cell migration. Overall, the SLM manufactured scaffold with the highest porosity, small pore size and pyramidal basic structure proved to be the most suitable structure for cell proliferation and migration.

  11. Influence of Different Three-Dimensional Open Porous Titanium Scaffold Designs on Human Osteoblasts Behavior in Static and Dynamic Cell Investigations.

    Science.gov (United States)

    Markhoff, Jana; Wieding, Jan; Weissmann, Volker; Pasold, Juliane; Jonitz-Heincke, Anika; Bader, Rainer

    2015-08-24

    In the treatment of osseous defects micro-structured three-dimensional materials for bone replacement serve as leading structure for cell migration, proliferation and bone formation. The scaffold design and culture conditions are crucial for the limited diffusion distance of nutrients and oxygen. In static culture, decreased cell activity and irregular distribution occur within the scaffold. Dynamic conditions entail physical stimulation and constant medium perfusion imitating physiological nutrient supply and metabolite disposal. Therefore, we investigated the influence of different scaffold configurations and cultivation methods on human osteoblasts. Cells were seeded on three-dimensional porous Ti-6Al-4V scaffolds manufactured with selective laser melting (SLM) or electron beam melting (EBM) varying in porosity, pore size and basic structure (cubic, diagonal, pyramidal) and cultured under static and dynamic conditions. Cell viability, migration and matrix production were examined via mitochondrial activity assay, fluorescence staining and ELISA. All scaffolds showed an increasing cell activity and matrix production under static conditions over time. Expectations about the dynamic culture were only partially fulfilled, since it enabled proliferation alike the static one and enhanced cell migration. Overall, the SLM manufactured scaffold with the highest porosity, small pore size and pyramidal basic structure proved to be the most suitable structure for cell proliferation and migration.

  12. Dynamic CT of hepatocellular carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Fujita, Nobuyuki; Shirato, Hiroki; Shinohara, Masahiro; Miyasaka, Kazuo; Morita, Yutaka; Irie, Goro

    1983-03-01

    We performed dynamic CT in 30 cases of hepatocellular carcinoma, and concluded as below. Detecting the stain in the early phase of the dynamic series, it is possible to make a diagnosis of hepatocellular carcinoma. The dynamic CT is effective in a case of small hepatocellular carcinoma in which it is difficult to gain an accurate diagnosis in the routine CT study. The dynamic CT is also effective in the differential diagnosis of hepatic lesions, as other hepatic lesions such as hemangioma and metastatic liver cancer show different patterns compared with hepatocellular carcinoma.

  13. An Emerging Natural History in the Development, Mechanisms and Worldwide Prevalence of Major Mental Disorders.

    Science.gov (United States)

    Pediaditakis, Nicholas

    2016-01-01

    Conciliating recent findings from molecular genetics, evolutionary biology, and clinical observations together point to new understandings regarding the mechanism, development and the persistent worldwide prevalence of major mental disorders (MMDs), which should be considered the result of an evolutionary downside trade off. Temperamental/trait variability, by facilitating choices for individual and group responses, confers robustness flexibility and resilience crucial to success of our species. Extreme temperamental variants, originating evolutionarily from the asocial aspect of human nature, also constitute the premorbid personality of the disorders. The latter create vulnerable individuals out of whom some will develop MMDs but at much higher rate to that of the general population. Significantly, similar temperamental "lopsidedness" enables many of these vulnerable individuals, if intelligent, tenacious, and curious, to be creative and contribute to our survival while some may also develop MMDs. All have a common neural-developmental origin and share characteristics in their clinical expression and pharmacological responses also expressed as mixed syndromes or alternating ones over time. Over-pruning of synaptic neurons may be considered the trigger of such occurrences or conversely, the failure to prevent them in spite of it. The symptoms of the major mental disorders are made up of antithetical substitutes as an expression of a disturbed over-all synchronizing property of brain function for all higher faculties previously unconsidered in their modeling. The concomitant presence of psychosis is a generic common occurrence.

  14. On the structural affinity of macromolecules with different biological properties: Molecular dynamics simulations of a series of TEM-1 mutants

    Energy Technology Data Exchange (ETDEWEB)

    Giampaolo, Alessia Di [Dipartimento di Scienze Fisiche e Chimiche, Universita’ degli Studi di l’Aquila, Via Vetoio snc, 67100 Coppito (AQ) (Italy); Mazza, Fernando [Department of Health Sciences, Univ. of L’Aquila, 67010 L’Aquila (Italy); Daidone, Isabella [Dipartimento di Scienze Fisiche e Chimiche, Universita’ degli Studi di l’Aquila, Via Vetoio snc, 67100 Coppito (AQ) (Italy); Amicosante, Gianfranco; Perilli, Mariagrazia [Dipartimento di Scienze Cliniche Applicate e Biotecnologiche, Università degli Studi di l’Aquila, Via Vetoio snc, 67100 Coppito (AQ) (Italy); Aschi, Massimiliano, E-mail: massimiliano.aschi@univaq.it [Dipartimento di Scienze Fisiche e Chimiche, Universita’ degli Studi di l’Aquila, Via Vetoio snc, 67100 Coppito (AQ) (Italy)

    2013-07-12

    Highlights: •We have performed molecular dynamics simulations of TEM-1 mutants. •Mutations effects on the mechanical properties are considered. •Mutants do not significantly alter the average enzymes structure. •Mutants produce sharp alterations in enzyme conformational repertoire. •Mutants also produce changes in the active site volume. -- Abstract: Molecular Dynamics simulations have been carried out in order to provide a molecular rationalization of the biological and thermodynamic differences observed for a class of TEM β-lactamases. In particular we have considered the TEM-1(wt), the single point mutants TEM-40 and TEM-19 representative of IRT and ESBL classes respectively, and TEM-1 mutant M182T, TEM-32 and TEM-20 which differ from the first three for the additional of M182T mutation. Results indicate that most of the thermodynamic, and probably biological behaviour of these systems arise from subtle effects which, starting from the alterations of the local interactions, produce drastic modifications of the conformational space spanned by the enzymes. The present study suggests that systems showing essentially the same secondary and tertiary structure may differentiate their chemical–biological activity essentially (and probably exclusively) on the basis of the thermal fluctuations occurring in their physiological environment.

  15. On the structural affinity of macromolecules with different biological properties: Molecular dynamics simulations of a series of TEM-1 mutants

    International Nuclear Information System (INIS)

    Giampaolo, Alessia Di; Mazza, Fernando; Daidone, Isabella; Amicosante, Gianfranco; Perilli, Mariagrazia; Aschi, Massimiliano

    2013-01-01

    Highlights: •We have performed molecular dynamics simulations of TEM-1 mutants. •Mutations effects on the mechanical properties are considered. •Mutants do not significantly alter the average enzymes structure. •Mutants produce sharp alterations in enzyme conformational repertoire. •Mutants also produce changes in the active site volume. -- Abstract: Molecular Dynamics simulations have been carried out in order to provide a molecular rationalization of the biological and thermodynamic differences observed for a class of TEM β-lactamases. In particular we have considered the TEM-1(wt), the single point mutants TEM-40 and TEM-19 representative of IRT and ESBL classes respectively, and TEM-1 mutant M182T, TEM-32 and TEM-20 which differ from the first three for the additional of M182T mutation. Results indicate that most of the thermodynamic, and probably biological behaviour of these systems arise from subtle effects which, starting from the alterations of the local interactions, produce drastic modifications of the conformational space spanned by the enzymes. The present study suggests that systems showing essentially the same secondary and tertiary structure may differentiate their chemical–biological activity essentially (and probably exclusively) on the basis of the thermal fluctuations occurring in their physiological environment

  16. Nonlinear dynamics in Nuclotron

    International Nuclear Information System (INIS)

    Dinev, D.

    1997-01-01

    The paper represents an extensive study of the nonlinear beam dynamics in the Nuclotron. Chromatic effects, including the dependence of the betatron tunes on the amplitude, and chromatic perturbations have been investigated taking into account the measured field imperfections. Beam distortion, smear, dynamic aperture and nonlinear acceptance have been calculated for different particle energies and betatron tunes

  17. Cultural geography. Different encounters, encountering difference

    OpenAIRE

    Longhurst, Robyn

    2007-01-01

    In the first half of this paper it is argued that cultural geography is a dynamic and diverse field that extends well beyond a single branch of human geography. The boundaries between it and other sub-disciplines are often blurred. People have «different» encounters with cultural geography depending on their sub-disciplinary convergences. People also have different encounters with cultural geography depending on where they live and work. «Place matters» in the construction, production and rep...

  18. Dealing with consumer differences in liking during repeated exposure to food; typical dynamics in rating behavior.

    Science.gov (United States)

    Dalenberg, Jelle R; Nanetti, Luca; Renken, Remco J; de Wijk, René A; Ter Horst, Gert J

    2014-01-01

    Consumers show high interindividual variability in food liking during repeated exposure. To investigate consumer liking during repeated exposure, data is often interpreted on a product level by averaging results over all consumers. However, a single product may elicit inconsistent behaviors in consumers; averaging will mix and hide possible subgroups of consumer behaviors, leading to a misinterpretation of the results. To deal with the variability in consumer liking, we propose to use clustering on data from consumer-product combinations to investigate the nature of the behavioral differences within the complete dataset. The resulting behavioral clusters can then be used to describe product acceptance. To test this approach we used two independent data sets in which young adults were repeatedly exposed to drinks and snacks, respectively. We found that five typical consumer behaviors existed in both datasets. These behaviors differed both in the average level of liking as well as its temporal dynamics. By investigating the distribution of a single product across typical consumer behaviors, we provide more precise insight in how consumers divide in subgroups based on their product liking (i.e. product modality). This work shows that taking into account and using interindividual differences can unveil information about product acceptance that would otherwise be ignored.

  19. Hierarchical nonlinear dynamics of human attention.

    Science.gov (United States)

    Rabinovich, Mikhail I; Tristan, Irma; Varona, Pablo

    2015-08-01

    Attention is the process of focusing mental resources on a specific cognitive/behavioral task. Such brain dynamics involves different partially overlapping brain functional networks whose interconnections change in time according to the performance stage, and can be stimulus-driven or induced by an intrinsically generated goal. The corresponding activity can be described by different families of spatiotemporal discrete patterns or sequential dynamic modes. Since mental resources are finite, attention modalities compete with each other at all levels of the hierarchy, from perception to decision making and behavior. Cognitive activity is a dynamical process and attention possesses some universal dynamical characteristics. Thus, it is time to apply nonlinear dynamical theory for the description and prediction of hierarchical attentional tasks. Such theory has to include the analyses of attentional control stability, the time cost of attention switching, the finite capacity of informational resources in the brain, and the normal and pathological bifurcations of attention sequential dynamics. In this paper we have integrated today's knowledge, models and results in these directions. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Exploring the Internal Dynamics of Globular Clusters

    Science.gov (United States)

    Watkins, Laura L.; van der Marel, Roeland; Bellini, Andrea; Luetzgendorf, Nora; HSTPROMO Collaboration

    2018-01-01

    Exploring the Internal Dynamics of Globular ClustersThe formation histories and structural properties of globular clusters are imprinted on their internal dynamics. Energy equipartition results in velocity differences for stars of different mass, and leads to mass segregation, which results in different spatial distributions for stars of different mass. Intermediate-mass black holes significantly increase the velocity dispersions at the centres of clusters. By combining accurate measurements of their internal kinematics with state-of-the-art dynamical models, we can characterise both the velocity dispersion and mass profiles of clusters, tease apart the different effects, and understand how clusters may have formed and evolved.Using proper motions from the Hubble Space Telescope Proper Motion (HSTPROMO) Collaboration for a set of 22 Milky Way globular clusters, and our discrete dynamical modelling techniques designed to work with large, high-quality datasets, we are studying a variety of internal cluster properties. We will present the results of theoretical work on simulated clusters that demonstrates the efficacy of our approach, and preliminary results from application to real clusters.

  1. Temporal dynamics of spectral bioindicators evidence biological and ecological differences among functional types in a cork oak open woodland

    Science.gov (United States)

    Cerasoli, Sofia; Costa e Silva, Filipe; Silva, João M. N.

    2016-06-01

    The application of spectral vegetation indices for the purpose of vegetation monitoring and modeling increased largely in recent years. Nonetheless, the interpretation of biophysical properties of vegetation through their spectral signature is still a challenging task. This is particularly true in Mediterranean oak forest characterized by a high spatial and temporal heterogeneity. In this study, the temporal dynamics of vegetation indices expected to be related with green biomass and photosynthetic efficiency were compared for the canopy of trees, the herbaceous layer, and two shrub species: cistus ( Cistus salviifolius) and ulex ( Ulex airensis). coexisting in a cork oak woodland. All indices were calculated from in situ measurements with a FieldSpec3 spectroradiometer (ASD Inc., Boulder, USA). Large differences emerged in the temporal trends and in the correlation between climate and vegetation indices. The relationship between spectral indices and temperature, radiation, and vapor pressure deficit for cork oak was opposite to that observed for the herbaceous layer and cistus. No correlation was observed between rainfall and vegetation indices in cork oak and ulex, but in the herbaceous layer and in the cistus, significant correlations were found. The analysis of spectral vegetation indices with fraction of absorbed PAR (fPAR) and quantum yield of chlorophyll fluorescence ( ΔF/ Fm') evidenced strongest relationships with the indices Normalized Difference Water Index (NDWI) and Photochemical Reflectance Index (PRI)512, respectively. Our results, while confirms the ability of spectral vegetation indices to represent temporal dynamics of biophysical properties of vegetation, evidence the importance to consider ecosystem composition for a correct ecological interpretation of results when the spatial resolution of observations includes different plant functional types.

  2. Modelling dynamic roughness during floods

    NARCIS (Netherlands)

    Paarlberg, Andries; Dohmen-Janssen, Catarine M.; Hulscher, Suzanne J.M.H.; Termes, A.P.P.

    2007-01-01

    In this paper, we present a dynamic roughness model to predict water levels during floods. Hysteresis effects of dune development are explicitly included. It is shown that differences between the new dynamic roughness model, and models where the roughness coefficient is calibrated, are most

  3. Discrete dynamical model of mechanisms determining the relations of biodiversity and stability at different levels of organization of living matter

    OpenAIRE

    Kabalyants, Petr; Nosov, Konstantin; Bespalov, Yuri

    2017-01-01

    The paper aims at building the model of relations of biodiversity and stability at different levels of organization of living matter with the use of discrete dynamical models. The relations revealed in the study are illustrated by case studies of zooplankton community of the eutrophicated lake and the colorimetric parameters of the microalgae community of phytobenthos and phytoperiphyton. The results offer: (1) new approaches to estimating the risk of mass development of toxic cyanobacteria i...

  4. Long-term simulations of water and isoproturon dynamics in a heterogeneous soil receiving different urban waste composts

    Science.gov (United States)

    Filipović, Vilim; Coquet, Yves; Pot, Valérie; Romić, Davor; Benoit, Pierre; Houot, Sabine

    2016-04-01

    Implementing various compost amendments and tillage practices has a large influence on soil structure and can create heterogeneities at the plot/field scale. While tillage affects soil physical properties, compost application influences also chemical properties like pesticide sorption and degradation. A long-term field experiment called "QualiAgro" (https://www6.inra.fr/qualiagro_eng/), conducted since 1998 aims at characterizing the agronomic value of urban waste composts and their environmental impacts. A modeling study was carried out using HYDRUS-2D for the 2004-2010 period to confront the effects of two different compost types combined with the presence of heterogeneities due to tillage in terms of water and isoproturon dynamics in soil. A municipal solid waste compost (MSW) and a co-compost of sewage sludge and green wastes (SGW) have been applied to experimental plots and compared to a control plot without any compost addition (CONT). Two wick lysimeters, 5 TDR probes, and 7 tensiometers were installed per plot to monitor water and isoproturon dynamics. In the ploughed layer, four zones with differing soil structure were identified: compacted clods (Δ), non-compacted soil (Γ), interfurrows (IF), and the plough pan (PP). These different soil structural zones were implemented into HYDRUS-2D according to field observation and using measured soil hydraulic properties. Lysimeter data showed (2004 -2010 period) that the CONT plot had the largest cumulative water outflow (1388 mm) compared to the MSW plot (962 mm) and SGW plot (979 mm). HYDRUS-2D was able to describe cumulative water outflow after calibration of soil hydraulic properties, for the whole 2004-2010 period with a model efficiency value of 0.99 for all three plots. Isoproturon leaching showed had the largest cumulative value in the CONT plot (21.31 μg) while similar cumulated isoproturon leachings were measured in the SGW (0.663 μg) and MSW (0.245 μg) plots. The model was able to simulate

  5. Geometrically nonlinear dynamic analysis of doubly curved isotropic shells resting on elastic foundation by a combination of harmonic differential quadrature-finite difference methods

    International Nuclear Information System (INIS)

    Civalek, Oemer

    2005-01-01

    The nonlinear dynamic response of doubly curved shallow shells resting on Winkler-Pasternak elastic foundation has been studied for step and sinusoidal loadings. Dynamic analogues of Von Karman-Donnel type shell equations are used. Clamped immovable and simply supported immovable boundary conditions are considered. The governing nonlinear partial differential equations of the shell are discretized in space and time domains using the harmonic differential quadrature (HDQ) and finite differences (FD) methods, respectively. The accuracy of the proposed HDQ-FD coupled methodology is demonstrated by numerical examples. The shear parameter G of the Pasternak foundation and the stiffness parameter K of the Winkler foundation have been found to have a significant influence on the dynamic response of the shell. It is concluded from the present study that the HDQ-FD methodolgy is a simple, efficient, and accurate method for the nonlinear analysis of doubly curved shallow shells resting on two-parameter elastic foundation

  6. Dynamic magnetizations and dynamic phase transitions in a transverse cylindrical Ising nanowire

    International Nuclear Information System (INIS)

    Deviren, Bayram; Ertaş, Mehmet; Keskin, Mustafa

    2012-01-01

    In this paper, we extend the paper of Kaneyoshi (2010 J. Magn. Magn. Mater. 322 3410-5) to investigate the dynamic magnetizations and dynamic phase transitions of a transverse cylindrical Ising nanowire system by using the effective field theory with correlations and the Glauber-type stochastic dynamics under a time-dependent oscillating external magnetic field. The dynamic effective field equations for the average longitudinal and transverse magnetizations on the surface shell and core are derived by using the Glauber transition rates. Temperature dependences of the dynamic longitudinal magnetizations, the transverse magnetizations and the total magnetizations are investigated in order to characterize the nature (first- or second-order) of the dynamic transitions as well as the dynamic phase transition temperatures and the compensation behaviors. The system is strongly affected by the surface situations. Some characteristic phenomena are found depending on the ratio of the physical parameters in the surface shell and the core. According to the values of Hamiltonian parameters, four different types of compensation behaviors in the Néel classification nomenclature exist in the system. The results are compared with some theoretical works and good overall agreement is observed. (paper)

  7. System Dynamics Modelling for a Balanced Scorecard

    DEFF Research Database (Denmark)

    Nielsen, Steen; Nielsen, Erland Hejn

    2008-01-01

    /methodology/approach - We use a case study model to develop time or dynamic dimensions by using a System Dynamics modelling (SDM) approach. The model includes five perspectives and a number of financial and non-financial measures. All indicators are defined and related to a coherent number of different cause...... have a major influence on other indicators and profit and may be impossible to predict without using a dynamic model. Practical implications - The model may be used as the first step in quantifying the cause-and-effect relationships of an integrated BSC model. Using the System Dynamics model provides......Purpose - To construct a dynamic model/framework inspired by a case study based on an international company. As described by the theory, one of the main difficulties of BSC is to foresee the time lag dimension of different types of indicators and their combined dynamic effects. Design...

  8. Ab initio molecular dynamics simulation of aqueous solution of nitric oxide in different formal oxidation states

    Science.gov (United States)

    Venâncio, Mateus F.; Rocha, Willian R.

    2015-10-01

    Ab initio molecular dynamics simulations were used to investigate the early chemical events involved in the dynamics of nitric oxide (NOrad), nitrosonium cation (NO+) and nitroxide anion (NO-) in aqueous solution. The NO+ ion is very reactive in aqueous solution having a lifetime of ∼4 × 10-13 s, which is shorter than the value of 3 × 10-10 s predicted experimentally. The NO+ reacts generating the nitrous acid as an intermediate and the NO2- ion as the final product. The dynamics of NOrad revealed the reversibly formation of a transient anion radical species HONOrad -.

  9. Selective Efficacy of Static and Dynamic Imagery in Different States of Physical Fatigue.

    Directory of Open Access Journals (Sweden)

    Thiago Ferreira Dias Kanthack

    Full Text Available There is compelling evidence that motor imagery contributes to improved motor performance, and recent work showed that dynamic motor imagery (dMI might provide additional benefits by comparison with traditional MI practice. However, the efficacy of motor imagery in different states of physical fatigue remains largely unknown, especially as imagery accuracy may be hampered by the physical fatigue states elicited by training. We investigated the effect of static motor imagery (sMI and dMI on free-throw accuracy in 10 high-level basketball athletes, both in a non-fatigued state (Experiment 1 and immediately after an incremental running test completed until exhaustion (20 m shuttle run-test-Experiment 2. We collected perceived exhaustion and heart rate to quantify the subjective experience of fatigue and energy expenditure. We found that dMI brought better shooting performance than sMI, except when athletes were physically exhausted. These findings shed light on the conditions eliciting optimal use of sMI and dMI. In particular, considering that the current physical state affects body representation, performing dMI under fatigue may result in mismatches between actual and predicted body states.

  10. Dynamics and control of hybrid mechanical systems

    NARCIS (Netherlands)

    Leonov, G.A.; Nijmeijer, H.; Pogromski, A.Y.; Fradkov, A.L.

    2010-01-01

    The papers in this edited volume aim to provide a better understanding of the dynamics and control of a large class of hybrid dynamical systems that are described by different models in different state space domains. They not only cover important aspects and tools for hybrid systems analysis and

  11. Synchronous dynamics of zooplankton competitors prevail in temperate lake ecosystems.

    Science.gov (United States)

    Vasseur, David A; Fox, Jeremy W; Gonzalez, Andrew; Adrian, Rita; Beisner, Beatrix E; Helmus, Matthew R; Johnson, Catherine; Kratina, Pavel; Kremer, Colin; de Mazancourt, Claire; Miller, Elizabeth; Nelson, William A; Paterson, Michael; Rusak, James A; Shurin, Jonathan B; Steiner, Christopher F

    2014-08-07

    Although competing species are expected to exhibit compensatory dynamics (negative temporal covariation), empirical work has demonstrated that competitive communities often exhibit synchronous dynamics (positive temporal covariation). This has led to the suggestion that environmental forcing dominates species dynamics; however, synchronous and compensatory dynamics may appear at different length scales and/or at different times, making it challenging to identify their relative importance. We compiled 58 long-term datasets of zooplankton abundance in north-temperate and sub-tropical lakes and used wavelet analysis to quantify general patterns in the times and scales at which synchronous/compensatory dynamics dominated zooplankton communities in different regions and across the entire dataset. Synchronous dynamics were far more prevalent at all scales and times and were ubiquitous at the annual scale. Although we found compensatory dynamics in approximately 14% of all combinations of time period/scale/lake, there were no consistent scales or time periods during which compensatory dynamics were apparent across different regions. Our results suggest that the processes driving compensatory dynamics may be local in their extent, while those generating synchronous dynamics operate at much larger scales. This highlights an important gap in our understanding of the interaction between environmental and biotic forces that structure communities. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  12. Comparison of bioassays with different exposure time patterns: the added value of dynamic modelling in predictive ecotoxicology.

    Science.gov (United States)

    Billoir, Elise; Delhaye, Hèlène; Forfait, Carole; Clément, Bernard; Triffault-Bouchet, Gaëlle; Charles, Sandrine; Delignette-Muller, Marie Laure

    2012-01-01

    The purpose of this study was to compare Daphnia magna responses to cadmium between two toxicity experiments performed in static and flow-through conditions. As a consequence of how water was renewed, the two experiments were characterised by two different exposure time patterns for daphnids, time-varying and constant, respectively. Basing on survival, growth and reproduction, we addressed the questions of organism development and sensitivity to cadmium. Classical analysis methods are not designed to deal with the time dimension and therefore not suitable to compare effects of different exposure time patterns. We used instead a dynamic modelling framework taking all timepoints and the time course of exposure into account, making comparable the results obtained from our two experiments. This modelling framework enabled us to detect an improvement of organism development in flow-through conditions compared to static ones and infer similar sensitivity to cadmium for both exposure time patterns. Copyright © 2011 Elsevier Inc. All rights reserved.

  13. [Analysis of dynamic changes of flavonoids and alkaloids during different drying process of Morus alba leaves].

    Science.gov (United States)

    Bai, Yong-liang; Duan, Jin-ao; Su, Shu-lan; Qian, Ye-fei; Qian, Da-wei; Ouyang, Zhen

    2014-07-01

    To find out dynamic changes of flavonoids and alkaloids in Morus alba leaves by analyzing influence of different drying method and drying degrees, in order to provide evidence for quality evaluation of Morus alba leaves. Different drying methods, programmed temperature methods and constant temperature methods were adopted to dry Morus alba leaves samples respectively. Contents of flavonoids and alkaloids were analyzed by HPLC-PDA and LC-TQ/MS respectively. It's shown obviously that the content of flavonoids were influenced heavily by different drying methods. Methods that suitable for flavonoids were freezing-dried > shade-dried > dried > sun-dried > microwave-dried > infrared-dried; Methods that suitable for alkaloids were freezing-dried > shade-dried > dried > sun-dried > infrared-dried > microwave-dried. The 55 -65 degrees C group was shown to be the lowest in both flavonoids and DNJ while the 85 - 95 degrees C group was shown to be the best for DNJ. For fagomine, the 45 degrees C group was shown to be the lowest concentrations while the 95 - 105 degrees C group was shown to be the highest. Samples with different moisture were shown to be different in content of flavonoids and alkaloids. And samples with 10% moisture contain highest flavonoids while those with 30% - 50% moisture contain lowest flavonoids. Content of DNJ and fagomine raised as moisture decreasing. In addition, the 55 - 65 degrees C group was better than the 95 -105 degrees C one in alkaloids content. The results provide optimal drying methods and condition for drying Morus alba leaves, and foundations for uncovering biochemical transform of Morus alba leaves.

  14. Dynamic Dependence and Diversification in Corporate Credit

    DEFF Research Database (Denmark)

    Christoffersen, Peter; Jacobs, Kris; Jin, Xisong

    We characterize dependence and tail dependence in corporate credit using a new class of dynamic copula models which can capture dynamic dependence and asymmetry in large samples of firms. We also document important differences between the dependence dynamics for credit spreads and equity returns...

  15. COMPARISON OF NONLINEAR DYNAMICS OPTIMIZATION METHODS FOR APS-U

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Y.; Borland, Michael

    2017-06-25

    Many different objectives and genetic algorithms have been proposed for storage ring nonlinear dynamics performance optimization. These optimization objectives include nonlinear chromaticities and driving/detuning terms, on-momentum and off-momentum dynamic acceptance, chromatic detuning, local momentum acceptance, variation of transverse invariant, Touschek lifetime, etc. In this paper, the effectiveness of several different optimization methods and objectives are compared for the nonlinear beam dynamics optimization of the Advanced Photon Source upgrade (APS-U) lattice. The optimized solutions from these different methods are preliminarily compared in terms of the dynamic acceptance, local momentum acceptance, chromatic detuning, and other performance measures.

  16. Water Dynamics in Protein Hydration Shells: The Molecular Origins of the Dynamical Perturbation

    Science.gov (United States)

    2014-01-01

    Protein hydration shell dynamics play an important role in biochemical processes including protein folding, enzyme function, and molecular recognition. We present here a comparison of the reorientation dynamics of individual water molecules within the hydration shell of a series of globular proteins: acetylcholinesterase, subtilisin Carlsberg, lysozyme, and ubiquitin. Molecular dynamics simulations and analytical models are used to access site-resolved information on hydration shell dynamics and to elucidate the molecular origins of the dynamical perturbation of hydration shell water relative to bulk water. We show that all four proteins have very similar hydration shell dynamics, despite their wide range of sizes and functions, and differing secondary structures. We demonstrate that this arises from the similar local surface topology and surface chemical composition of the four proteins, and that such local factors alone are sufficient to rationalize the hydration shell dynamics. We propose that these conclusions can be generalized to a wide range of globular proteins. We also show that protein conformational fluctuations induce a dynamical heterogeneity within the hydration layer. We finally address the effect of confinement on hydration shell dynamics via a site-resolved analysis and connect our results to experiments via the calculation of two-dimensional infrared spectra. PMID:24479585

  17. Nectar production dynamics and sugar composition in two Mucuna species (Leguminosae, Faboideae) with different specialized pollinators

    Science.gov (United States)

    Agostini, Kayna; Sazima, Marlies; Galetto, Leonardo

    2011-11-01

    Nectar is secreted in particular rhythms throughout the lifespan of a flower, which allows determining the nectar production dynamics. This paper compares nectar features in Mucuna japira and Mucuna urens describing: dynamics of nectar production, floral response to nectar removal, resorption, nectar sugar composition, and variation in nectar sugar composition. M. japira inflorescence bears 12-21 yellow flowers, which are in anthesis for 7 days, whereas M. urens inflorescence bears 36-54 greenish flowers, but only 1-3 flowers are in anthesis simultaneously that last one night. Nectar volume and sugar concentration were measured, and the amount of sugar was estimated. Qualitative and quantitative nectar sugar composition was determined. Both species had a constant nectar sugar concentration (ca. 10% for M. japira and ca. 16% for M. urens) and secreted high volumes of nectar (ca. 340 μl per flower for M. japira and 310 μl per flower for M. urens), during 5 days for M. japira and 6 h for M. urens, but after the first removal, i.e., when flower opening mechanism is triggered, nectar production stops immediately. Nectar resorption occurred in both species. Nectar sugar composition showed some similarities between the species. Variation in nectar sugar composition occurred in both species. The Mucuna species are dependent on their pollinators to produce fruits and seeds, and they have different strategies to promote the necessary interaction with birds or bats, especially related to nectar and flower characteristics.

  18. Parental Socialization, Vagal Regulation, and Preschoolers' Anxious Difficulties: Direct Mothers and Moderated Fathers

    Science.gov (United States)

    Hastings, Paul D.; Sullivan, Caroline; McShane, Kelly E.; Coplan, Robert J.; Utendale, William T.; Vyncke, Johanna D.

    2008-01-01

    Parental supportiveness and protective overcontrol and preschoolers' parasympathetic regulation were examined as predictors of temperamental inhibition, social wariness, and internalizing problems. Lower baseline vagal tone and weaker vagal suppression were expected to mark poorer dispositional self-regulatory capacity, leaving children more…

  19. On the relationship between temperament, metacognition, and anxiety : independent and mediated effects

    NARCIS (Netherlands)

    Dragan, Malgorzata; Dragan, Wojciech L.; Kononowicz, Tadeusz; Wells, Adrian

    2012-01-01

    The present study examined the relations between temperamental traits distinguished in regulative theory of temperament, state anxiety, and metacognition as postulated in self-regulatory executive function (S-REF) theory of emotional disorder. Data analysis (n = 315) consisted of independent and

  20. Dynamic backcalculation with different load-time histories

    DEFF Research Database (Denmark)

    Madsen, Stine Skov; Levenberg, Eyal

    2017-01-01

    This paper focused attention to the falling weight deflectometer (FWD) load-time history. For a commonly used device, it studied the pulse generation mechanism and the influence of different load histories on backcalculation results. In this connection, a semi-analytic impact theory was first...... for an experimental dataset that resulted from operating an FWD with different loading configurations. It was found that backcalculated parameters are sensitive to the FWD pulse features. Consequently, it is recommended that, whenever advanced pavement characterisation is sought, experimental attention should...

  1. Entropy of dynamical social networks

    Science.gov (United States)

    Zhao, Kun; Karsai, Marton; Bianconi, Ginestra

    2012-02-01

    Dynamical social networks are evolving rapidly and are highly adaptive. Characterizing the information encoded in social networks is essential to gain insight into the structure, evolution, adaptability and dynamics. Recently entropy measures have been used to quantify the information in email correspondence, static networks and mobility patterns. Nevertheless, we still lack methods to quantify the information encoded in time-varying dynamical social networks. In this talk we present a model to quantify the entropy of dynamical social networks and use this model to analyze the data of phone-call communication. We show evidence that the entropy of the phone-call interaction network changes according to circadian rhythms. Moreover we show that social networks are extremely adaptive and are modified by the use of technologies such as mobile phone communication. Indeed the statistics of duration of phone-call is described by a Weibull distribution and is significantly different from the distribution of duration of face-to-face interactions in a conference. Finally we investigate how much the entropy of dynamical social networks changes in realistic models of phone-call or face-to face interactions characterizing in this way different type human social behavior.

  2. Knotting dynamics of DNA chains of different length confined in nanochannels

    International Nuclear Information System (INIS)

    Suma, Antonio; Micheletti, Cristian; Orlandini, Enzo

    2015-01-01

    Langevin dynamics simulations are used to characterize the typical mechanisms governing the spontaneous tying, untying and the dynamical evolution of knots in coarse-grained models of DNA chains confined in nanochannels. In particular we focus on how these mechanisms depend on the chain contour length, L c , at a fixed channel width D = 56 nm corresponding to the onset of the Odijk scaling regime where chain backfoldings and hence knots are disfavoured but not suppressed altogether. We find that the lifetime of knots grows significantly with L c , while that of unknots varies to a lesser extent. The underlying kinetic mechanisms are clarified by analysing the evolution of the knot position along the chain. At the considered confinement, in fact, knots are typically tied by local backfoldings of the chain termini where they are eventually untied after a stochastic motion along the chain. Consequently, the lifetime of unknots is mostly controlled by backfoldings events at the chain ends, which is largely independent of L c . The lifetime of knots, instead, increases significantly with L c because knots can, on average, travel farther along the chain before being untied. The observed interplay of knots and unknots lifetimes underpins the growth of the equilibrium knotting probability of longer and longer chains at fixed channel confinement. (paper)

  3. A comparison of take-off dynamics during three different spikes, block and counter-movement jump in female volleyball players.

    Science.gov (United States)

    Kabacinski, Jaroslae; Dworak, Lecholslaw B; Murawa, Michal; Ostarello, John; Rzepnicka, Agata; Maczynski, Jacek

    2016-12-01

    The purpose of the study was to compare the take-off dynamics in counter-movement jump (CMJ), volleyball block and spikes. Twelve professional female players, representing the highest volleyball league in Poland, participated in the laboratory tests. A force platform was used to record ground reaction force (GRF) during take-off phase in CMJ test, block from a run-up and spikes: front row attack, slide attack, back row attack. Vertical (v) GRF (peak: Rmax and integral mean: ), impulse of vGRF (J) and mechanical power (peak: Pmax and integral mean: ) were analyzed. Significant differences (P, J, Pmax, and ) were found between CMJ, block from a run-up and three different technique spikes. The highest values were recorded during take-off in the back row attack: peak vGRF (2.93±0.05 BW), integral mean vGRF (1.90±0.08 BW), impulse of vGRF (354±40 Ns), peak power (5320±918 W) and integral mean power (3604±683 W). Peak power (2608±217 W) and integral mean power (1417±94 W) were determined in CMJ test to evaluate the force-velocity capabilities of the players. In terms of GRF and the mechanical power, high level of dynamics in take-off influences positively the jumping height and significantly increases the effectiveness of attacks during spike of the ball over the block of the opponent.

  4. Difference Principle and Black-hole Thermodynamics

    OpenAIRE

    Martin, Pete

    2009-01-01

    The heuristic principle that constructive dynamics may arise wherever there exists a difference, or gradient, is discussed. Consideration of black-hole entropy appears to provide a clue for setting a lower bound on any extensive measure of such collective system difference, or potential to give rise to constructive dynamics. It is seen that the second-power dependence of black-hole entropy on mass is consistent with the difference principle, while consideration of Hawking radiation forces one...

  5. Seasonally dynamic fungal communities in the Quercus macrocarpa phyllosphere differ between urban and nonurban environments.

    Science.gov (United States)

    Jumpponen, A; Jones, K L

    2010-04-01

    *The fungal richness, diversity and community composition in the Quercus macrocarpa phyllosphere were compared across a growing season in trees located in six stands within and outside a small urban center using 454-sequencing and DNA tagging. The approaches did not differentiate between endophytic and epiphytic fungal communities. *Fungi accumulated in the phyllosphere rapidly and communities were temporally dynamic, with more than a third of the analyzed operational taxonomic units (OTUs) and half of the BLAST-inferred genera showing distinct seasonal patterns. The seasonal patterns could be explained by fungal life cycles or environmental tolerances. *The communities were hyperdiverse and differed between the urban and nonurban stands, albeit not consistently across the growing season. Foliar macronutrients (nitrogen (N), potassium (K) and sulfur (S)), micronutrients (boron (B), manganese (Mn) and selenium (Se)) and trace elements (cadmium (Cd), lead (Pb) and zinc (Zn)) were enriched in the urban trees, probably as a result of anthropogenic activities. Because of correlations with the experimental layout, these chemical elements should not be considered as community drivers without further empirical studies. *We suggest that a combination of mechanisms leads to differences between urban and nonurban communities. Among those are stand isolation and size, nutrient and pollutant accumulation plus stand management, including fertilization and litter removal.

  6. Performance of dynamic safety barriers-Structuring, modelling and visualization

    OpenAIRE

    Wikdahl, Olga

    2014-01-01

    The main objective of this master thesis is to discuss performance of dynamic safety barriers. A comprehensive literature review is performed in order to get understanding what dynamic safety barrier is. Three different concepts of dynamic safety barriers based on various meanings of dynamic were derived from the literature review: - dynamic safety barriers related to motion or physical force - dynamic safety barriers as updated barriers from dynamic risk analysis - dynamic safety ...

  7. The many faces of graph dynamics

    Science.gov (United States)

    Pignolet, Yvonne Anne; Roy, Matthieu; Schmid, Stefan; Tredan, Gilles

    2017-06-01

    The topological structure of complex networks has fascinated researchers for several decades, resulting in the discovery of many universal properties and reoccurring characteristics of different kinds of networks. However, much less is known today about the network dynamics: indeed, complex networks in reality are not static, but rather dynamically evolve over time. Our paper is motivated by the empirical observation that network evolution patterns seem far from random, but exhibit structure. Moreover, the specific patterns appear to depend on the network type, contradicting the existence of a ‘one fits it all’ model. However, we still lack observables to quantify these intuitions, as well as metrics to compare graph evolutions. Such observables and metrics are needed for extrapolating or predicting evolutions, as well as for interpolating graph evolutions. To explore the many faces of graph dynamics and to quantify temporal changes, this paper suggests to build upon the concept of centrality, a measure of node importance in a network. In particular, we introduce the notion of centrality distance, a natural similarity measure for two graphs which depends on a given centrality, characterizing the graph type. Intuitively, centrality distances reflect the extent to which (non-anonymous) node roles are different or, in case of dynamic graphs, have changed over time, between two graphs. We evaluate the centrality distance approach for five evolutionary models and seven real-world social and physical networks. Our results empirically show the usefulness of centrality distances for characterizing graph dynamics compared to a null-model of random evolution, and highlight the differences between the considered scenarios. Interestingly, our approach allows us to compare the dynamics of very different networks, in terms of scale and evolution speed.

  8. Scaling dynamic response and destructive metabolism in an immunosurveillant anti-tumor system modulated by different external periodic interventions.

    Directory of Open Access Journals (Sweden)

    Yuanzhi Shao

    Full Text Available On the basis of two universal power-law scaling laws, i.e. the scaling dynamic hysteresis in physics and the allometric scaling metabolism in biosystem, we studied the dynamic response and the evolution of an immunosurveillant anti-tumor system subjected to a periodic external intervention, which is equivalent to the scheme of a radiotherapy or chemotherapy, within the framework of the growth dynamics of tumor. Under the modulation of either an abrupt or a gradual change external intervention, the population density of tumors exhibits a dynamic hysteresis to the intervention. The area of dynamic hysteresis loop characterizes a sort of dissipative-therapeutic relationship of the dynamic responding of treated tumors with the dose consumption of accumulated external intervention per cycle of therapy. Scaling the area of dynamic hysteresis loops against the intensity of an external intervention, we deduced a characteristic quantity which was defined as the theoretical therapeutic effectiveness of treated tumor and related with the destructive metabolism of tumor under treatment. The calculated dose-effectiveness profiles, namely the dose cumulant per cycle of intervention versus the therapeutic effectiveness, could be well scaled into a universal quadratic formula regardless of either an abrupt or a gradual change intervention involved. We present a new concept, i.e., the therapy-effect matrix and the dose cumulant matrix, to expound the new finding observed in the growth and regression dynamics of a modulated anti-tumor system.

  9. Quantumness-generating capability of quantum dynamics

    Science.gov (United States)

    Li, Nan; Luo, Shunlong; Mao, Yuanyuan

    2018-04-01

    We study quantumness-generating capability of quantum dynamics, where quantumness refers to the noncommutativity between the initial state and the evolving state. In terms of the commutator of the square roots of the initial state and the evolving state, we define a measure to quantify the quantumness-generating capability of quantum dynamics with respect to initial states. Quantumness-generating capability is absent in classical dynamics and hence is a fundamental characteristic of quantum dynamics. For qubit systems, we present an analytical form for this measure, by virtue of which we analyze several prototypical dynamics such as unitary dynamics, phase damping dynamics, amplitude damping dynamics, and random unitary dynamics (Pauli channels). Necessary and sufficient conditions for the monotonicity of quantumness-generating capability are also identified. Finally, we compare these conditions for the monotonicity of quantumness-generating capability with those for various Markovianities and illustrate that quantumness-generating capability and quantum Markovianity are closely related, although they capture different aspects of quantum dynamics.

  10. Surface-Assisted Dynamic Search Processes.

    Science.gov (United States)

    Shin, Jaeoh; Kolomeisky, Anatoly B

    2018-03-01

    Many chemical and biological systems exhibit intermittent search phenomena when participating particles alternate between dynamic regimes with different dimensionalities. Here we investigate theoretically a dynamic search process of finding a small target on a two-dimensional surface starting from a bulk solution, which is an example of such an intermittent search process. Both continuum and discrete-state stochastic descriptions are developed. It is found that depending on the scanning length λ, which describes the area visited by the reacting molecule during one search cycle, the system can exhibit three different search regimes: (i) For small λ values, the reactant finds the target mostly via three-dimensional bulk diffusion; (ii) for large λ values, the reactant molecule associates to the target mostly via surface diffusion; and (iii) for intermediate λ values, the reactant reaches the target via a combination of three-dimensional and two-dimensional search cycles. Our analysis also shows that the mean search times have different scalings as a function of the size of the surface segment depending on the nature of the dynamic search regime. Search dynamics are also sensitive to the position of the target for large scanning lengths. In addition, it is argued that the continuum description underestimates mean search times and does not always correctly describe the most optimal conditions for the surface-assisted dynamic processes. The importance of our findings for real natural systems is discussed.

  11. Global Analysis of Nonlinear Dynamics

    CERN Document Server

    Luo, Albert

    2012-01-01

    Global Analysis of Nonlinear Dynamics collects chapters on recent developments in global analysis of non-linear dynamical systems with a particular emphasis on cell mapping methods developed by Professor C.S. Hsu of the University of California, Berkeley. This collection of contributions prepared by a diverse group of internationally recognized researchers is intended to stimulate interests in global analysis of complex and high-dimensional nonlinear dynamical systems, whose global properties are largely unexplored at this time. This book also: Presents recent developments in global analysis of non-linear dynamical systems Provides in-depth considerations and extensions of cell mapping methods Adopts an inclusive style accessible to non-specialists and graduate students Global Analysis of Nonlinear Dynamics is an ideal reference for the community of nonlinear dynamics in different disciplines including engineering, applied mathematics, meteorology, life science, computational science, and medicine.  

  12. The effect of host relaxation and dynamics on guest molecule dynamics in H2/tetrahydrofuranhydrate.

    Science.gov (United States)

    Peterson, Vanessa K; Shoko, Elvis; Kearley, Gordon J

    2011-01-01

    We use ab initio molecular dynamics simulations to obtain classically the effects of H2O cage motions on the potential-energy surface (PES) of encapsulated H2 in the H2/tetrahydrofuran-hydrate system. The significant differences between the PES for the H2 in rigid and flexible cages that we find will influence calculation of the quantum dynamics of the H2. Part of these differences arises from the relaxation of the H2O cage around the classical H2, with a second part arising from the coupling of both translational and rotational motions of H2 with the H20 cage. We find that isotopic substitution of 2H for 1H of the H2O cage affects the coupling, which has implications for experiments that require the use of 2H2O, including inelastic neutron scattering that uses 2H2O cages in order to focus on the H2 guest dynamics. Overall, this work emphasizes the importance of taking into account cage dynamics in any approach used to understand the dynamics of H2 guests in porous framework materials.

  13. Study on Triopoly Dynamic Game Model Based on Different Demand Forecast Methods in the Market

    Directory of Open Access Journals (Sweden)

    Junhai Ma

    2017-01-01

    Full Text Available The impact of inaccurate demand beliefs on dynamics of a Triopoly game is studied. We suppose that all the players make their own estimations on possible demand with errors. A dynamic Triopoly game with such demand belief is set up. Based on this model, existence and local stable region of the equilibriums are investigated by 3D stable regions of Nash equilibrium point. The complex dynamics, such as bifurcation scenarios and route to chaos, are displayed in 2D bifurcation diagrams, in which e1 and α are negatively related to each other. Basins of attraction are investigated and we found that the attraction domain becomes smaller with the increase in price modification speed, which indicates that all the players’ output must be kept within a certain range so as to keep the system stable. Feedback control method is used to keep the system at an equilibrium state.

  14. Shadowing in dynamical systems

    CERN Document Server

    Pilyugin, Sergei Yu

    1999-01-01

    This book is an introduction to the theory of shadowing of approximate trajectories in dynamical systems by exact ones. This is the first book completely devoted to the theory of shadowing. It shows the importance of shadowing theory for both the qualitative theory of dynamical systems and the theory of numerical methods. Shadowing Methods allow us to estimate differences between exact and approximate solutions on infinite time intervals and to understand the influence of error terms. The book is intended for specialists in dynamical systems, for researchers and graduate students in the theory of numerical methods.

  15. Stabilities and Dynamics of Protein Folding Nuclei by Molecular Dynamics Simulation

    Science.gov (United States)

    Song, Yong-Shun; Zhou, Xin; Zheng, Wei-Mou; Wang, Yan-Ting

    2017-07-01

    To understand how the stabilities of key nuclei fragments affect protein folding dynamics, we simulate by molecular dynamics (MD) simulation in aqueous solution four fragments cut out of a protein G, including one α-helix (seqB: KVFKQYAN), two β-turns (seqA: LNGKTLKG and seqC: YDDATKTF), and one β-strand (seqD: DGEWTYDD). The Markov State Model clustering method combined with the coarse-grained conformation letters method are employed to analyze the data sampled from 2-μs equilibrium MD simulation trajectories. We find that seqA and seqB have more stable structures than their native structures which become metastable when cut out of the protein structure. As expected, seqD alone is flexible and does not have a stable structure. Throughout our simulations, the native structure of seqC is stable but cannot be reached if starting from a structure other than the native one, implying a funnel-shape free energy landscape of seqC in aqueous solution. All the above results suggest that different nuclei have different formation dynamics during protein folding, which may have a major contribution to the hierarchy of protein folding dynamics. Supported by the National Basic Research Program of China under Grant No. 2013CB932804, the National Natural Science Foundation of China under Grant No. 11421063, and the CAS Biophysics Interdisciplinary Innovation Team Project

  16. Effect of speed on local dynamic stability of locomotion under different task constraints in running.

    Science.gov (United States)

    Mehdizadeh, Sina; Arshi, Ahmed Reza; Davids, Keith

    2014-01-01

    A number of studies have investigated effects of speed on local dynamic stability of walking, although this relationship has been rarely investigated under changing task constraints, such as during forward and backward running. To rectify this gap in the literature, the aim of this study was to investigate the effect of running speed on local dynamic stability of forward and backward running on a treadmill. Fifteen healthy male participants took part in this study. Participants ran in forward and backward directions at speeds of 80%, 100% and 120% of their preferred running speed. The three-dimensional motion of a C7 marker was recorded using a motion capture system. Local dynamic stability of the marker was quantified using short- and long-term largest finite-time Lyapunov exponents (LyE). Results showed that short-term largest finite-time LyE values increased with participant speed meaning that local dynamic stability decreased with increasing speed. Long-term largest finite-time LyEs, however, remained unaffected as speed increased. Results of this study indicated that, as in walking, slow running is more stable than fast running. These findings improve understanding of how stability is regulated when constraints on the speed of movements is altered. Implications for the design of rehabilitation or sport practice programmes suggest how task constraints could be manipulated to facilitate adaptations in locomotion stability during athletic training.

  17. Dynamics of dielectric barrier discharges in different arrangements

    International Nuclear Information System (INIS)

    Gibalov, Valentin I; Pietsch, Gerhard J

    2012-01-01

    Based on experimental results, numerical investigations of dielectric barrier discharges (DBDs) have been performed in three basic configurations: in the volume, coplanar and surface discharge arrangements. It is shown that the DBD dynamics is the same in all arrangements and it is determined by the development of a few principal constituents, i.e. cathode- and anode-directed streamers, discharge channel, cathode layer and surface charges. It is found that the anode- and cathode-directed streamers appear with a highly conductive channel in between. The interaction of the streamers with conductive and dielectric surfaces determines the filamentary or homogeneous appearance of the discharge and its properties. The cathode-directed streamer is a self-sustaining phenomenon, which moves in a gas gap or along an electrode driven by a positive loop-back between photoemission and electron multiplication. The anode-directed streamer plays a subsidiary role. Depending on the kind of gas (electronegative or electropositive) and/or the degree of development of the cathode-directed streamer, the field strength in the conductive channels changes significantly. When the cathode-directed streamer touches the electrode surface, a cathode layer appears with parameters close to those of normal glow discharges. In volume discharge arrangements the movement of the streamers results in the appearance of Lichtenberg figures on dielectric surfaces. (paper)

  18. Nonlinear Dynamic Models in Advanced Life Support

    Science.gov (United States)

    Jones, Harry

    2002-01-01

    To facilitate analysis, ALS systems are often assumed to be linear and time invariant, but they usually have important nonlinear and dynamic aspects. Nonlinear dynamic behavior can be caused by time varying inputs, changes in system parameters, nonlinear system functions, closed loop feedback delays, and limits on buffer storage or processing rates. Dynamic models are usually cataloged according to the number of state variables. The simplest dynamic models are linear, using only integration, multiplication, addition, and subtraction of the state variables. A general linear model with only two state variables can produce all the possible dynamic behavior of linear systems with many state variables, including stability, oscillation, or exponential growth and decay. Linear systems can be described using mathematical analysis. Nonlinear dynamics can be fully explored only by computer simulations of models. Unexpected behavior is produced by simple models having only two or three state variables with simple mathematical relations between them. Closed loop feedback delays are a major source of system instability. Exceeding limits on buffer storage or processing rates forces systems to change operating mode. Different equilibrium points may be reached from different initial conditions. Instead of one stable equilibrium point, the system may have several equilibrium points, oscillate at different frequencies, or even behave chaotically, depending on the system inputs and initial conditions. The frequency spectrum of an output oscillation may contain harmonics and the sums and differences of input frequencies, but it may also contain a stable limit cycle oscillation not related to input frequencies. We must investigate the nonlinear dynamic aspects of advanced life support systems to understand and counter undesirable behavior.

  19. Allele-dependent differences in quorum-sensing dynamics result in variant expression of virulence genes in Staphylococcus aureus.

    Science.gov (United States)

    Geisinger, Edward; Chen, John; Novick, Richard P

    2012-06-01

    Agr is an autoinducing, quorum-sensing system that functions in many Gram-positive species and is best characterized in the pathogen Staphylococcus aureus, in which it is a global regulator of virulence gene expression. Allelic variations in the agr genes have resulted in the emergence of four quorum-sensing specificity groups in S. aureus, which correlate with different strain pathotypes. The basis for these predilections is unclear but is hypothesized to involve the phenomenon of quorum-sensing interference between strains of different agr groups, which may drive S. aureus strain isolation and divergence. Whether properties intrinsic to each agr allele directly influence virulence phenotypes within S. aureus is unknown. In this study, we examined group-specific differences in agr autoinduction and virulence gene regulation by utilizing congenic strains, each harboring a unique S. aureus agr allele, enabling a dissection of agr locus-dependent versus genotype-dependent effects on quorum-sensing dynamics and virulence factor production. Employing a reporter fusion to the principal agr promoter, P3, we observed allele-dependent differences in the timing and magnitude of agr activation. These differences were mediated by polymorphisms within the agrBDCA genes and translated to significant variations in the expression of a key transcriptional regulator, Rot, and of several important exoproteins and surface factors involved in pathogenesis. This work uncovers the contribution of divergent quorum-sensing alleles to variant expression of virulence determinants within a bacterial species.

  20. Dynamic Diversification in Corporate Credit

    DEFF Research Database (Denmark)

    Christoffersen, Peter; Jacobs, Kris; Jin, Xisong

    We characterize diversification in corporate credit using a new class of dynamic copula models which can capture dynamic dependence and asymmetry in large samples of firms. We also document important differences between credit spread and equity return dependence dynamics. Modeling a decade...... the crisis and remain high as well. The most important shocks to credit dependence occur in August of 2007 and in August of 2011, but interestingly these dates are not associated with significant changes to median credit spreads....

  1. Nonlinearities Lead to Qualitative Differences in Population Dynamics of Predator-Prey Systems

    Czech Academy of Sciences Publication Activity Database

    Ameixa, Olga; Messelink, G. J.; Kindlmann, Pavel

    2013-01-01

    Roč. 8, č. 4 (2013), e62530-e62530 E-ISSN 1932-6203 R&D Projects: GA MŠk(CZ) ED1.1.00/02.0073; GA ČR(CZ) GEVOL/11/E036 Institutional support: RVO:67179843 Keywords : nonlinear system * population density * population dynamics * predator * predator prey interaction * qualitative analysis Subject RIV: EH - Ecology, Behaviour Impact factor: 3.534, year: 2013

  2. Unsteady Vibration Aerodynamic Modeling and Evaluation of Dynamic Derivatives Using Computational Fluid Dynamics

    Directory of Open Access Journals (Sweden)

    Xu Liu

    2015-01-01

    Full Text Available Unsteady aerodynamic system modeling is widely used to solve the dynamic stability problems encountering aircraft design. In this paper, single degree-of-freedom (SDF vibration model and forced simple harmonic motion (SHM model for dynamic derivative prediction are developed on the basis of modified Etkin model. In the light of the characteristics of SDF time domain solution, the free vibration identification methods for dynamic stability parameters are extended and applied to the time domain numerical simulation of blunted cone calibration model examples. The dynamic stability parameters by numerical identification are no more than 0.15% deviated from those by experimental simulation, confirming the correctness of SDF vibration model. The acceleration derivatives, rotary derivatives, and combination derivatives of Army-Navy Spinner Rocket are numerically identified by using unsteady N-S equation and solving different SHV patterns. Comparison with the experimental result of Army Ballistic Research Laboratories confirmed the correctness of the SHV model and dynamic derivative identification. The calculation result of forced SHM is better than that by the slender body theory of engineering approximation. SDF vibration model and SHM model for dynamic stability parameters provide a solution to the dynamic stability problem encountering aircraft design.

  3. A study on the future of unconventional oil development under different oil price scenarios: A system dynamics approach

    International Nuclear Information System (INIS)

    Hosseini, Seyed Hossein; Shakouri, Hamed G.

    2016-01-01

    Fluctuations in the oil global market has been a critical topic for the world economy so that analyzing and forecasting the conventional oil production rate has been examined by many researchers thoroughly. However, the dynamics of the market has not been studied systematically with regard to the new emerging competitors, namely unconventional oil. In this paper, the future trend of conventional and unconventional oil production and capacity expansion rates are analyzed using system dynamics approach. To do so, a supply-side modeling approach is utilized while main effective loops are modeled mathematically as follows: technological learning and progress, long and short-term profitability of oil capacity expansion and production, and oil proved reserve limitations. The proposed model is used to analyze conventional and unconventional oil production shares, up to 2025, under different oil price scenarios. The results show that conventional oil production rate ranges from 79.995 to 87.044 MB/day, which is 75–80 percent of total oil production rate, while unconventional oil production rate ranges from 19.615 to 28.584 MB/day. Simulation results reveal that unconventional oil can gain a considerable market share in the short run, although conventional oil will remain as the major source for the market in the long run. - Highlights: • Variables and loops affecting oil production are formulated mathematically. • Shares of conventional and unconventional oil in the global oil market is analyzed. • Oil production rate under different oil price scenarios up to 2025 is simulated. • Unconventional oil would obtain a considerable share in market in the short-term. • A late peak for the conventional oil resources would occur.

  4. Annular dynamics after mitral valve repair with different prosthetic rings: A real-time three-dimensional transesophageal echocardiography study.

    Science.gov (United States)

    Nishi, Hiroyuki; Toda, Koichi; Miyagawa, Shigeru; Yoshikawa, Yasushi; Fukushima, Satsuki; Kawamura, Masashi; Yoshioka, Daisuke; Saito, Tetsuya; Ueno, Takayoshi; Kuratani, Toru; Sawa, Yoshiki

    2016-09-01

    We assessed the effects of different types of prosthetic rings on mitral annular dynamics using real-time three-dimensional echocardiography (RT3DE). RT3DE was performed in 44 patients, including patients undergoing mitral annuloplasty using the Cosgrove-Edwards flexible band (Group A, n = 10), the semi-rigid Sorin Memo 3D ring (Group B, n = 17), the semi-rigid Edwards Physio II ring (Group C, n = 7) and ten control subjects. Various annular diameters were measured throughout the cardiac cycle. We observed flexible anterior annulus motion in all of the groups except Group C. A flexible posterior annulus was only observed in Group B and the Control group. The mitral annular area changed during the cardiac cycle by 8.4 ± 3.2, 6.3 ± 2.0, 3.2 ± 1.3, and 11.6 ± 5.0 % in Group A, Group B, Group C, and the Control group, respectively. The dynamic diastolic to systolic change in mitral annular diameters was lost in Group C, while it was maintained in Group A, and to a good degree in Group B. In comparison to the Control group, the mitral annulus shape was more ellipsoid in Group B and Group C, and more circular in Group A. Although mitral regurgitation was well controlled by all of the types of rings that were utilized in the present study, we demonstrated that the annulus motion and annulus shape differed according to the type of prosthetic ring that was used, which might provide important information for the selection of an appropriate prosthetic ring.

  5. The association between social phobia, social anxiety cognitions and paranoid symptoms.

    Science.gov (United States)

    Schutters, S I J; Dominguez, M-d-G; Knappe, S; Lieb, R; van Os, J; Schruers, K R J; Wittchen, H-U

    2012-03-01

    Previous research suggests high levels of comorbidity between social phobia and paranoid symptoms, although the nature of this association remains unclear. Data were derived from the Early Developmental Stages of Psychopathology study, a 10-year longitudinal study in a representative German community sample of 3021 participants aged 14-24 years at baseline. The Munich-Composite International Diagnostic Interview was used to assess social phobia and paranoid symptoms, along with data on social phobia features. Cross-sectional and longitudinal analyses were conducted. Differential associations with environmental risk factors and temperamental traits were investigated. Lifetime social phobia and paranoid symptoms were associated with each other cross-sectionally (OR = 1.80, 95% CI = 1.31-2.47). Lifetime paranoid symptoms were associated specifically with social anxiety cognitions. Lifetime cognitions of negative evaluation predicted later onset of paranoid symptoms, whereas onset of social phobia was predicted by cognitions of loss of control and fear/avoidance of social situations. Lifetime social phobia and paranoid symptoms shared temperamental traits of behavioural inhibition, but differed in environmental risks. The present study showed that paranoid symptoms and social phobia share similarities in cognitive profile and inhibited temperament. Avoidance appears to be important in the development of social phobia, whereas cannabis use and traumatic experiences may drive paranoid thinking in vulnerable individuals. © 2011 John Wiley & Sons A/S.

  6. Weakened Resilience in Parenting Self-Efficacy in Pregnant Women Who Were Abused in Childhood: An Experimental Test.

    Directory of Open Access Journals (Sweden)

    Florentina C Kunseler

    Full Text Available This study tested experimentally whether the combination of a history of childhood abuse and confrontation with difficult infant temperament is associated with negative changes in parenting self-efficacy. First-time pregnant women (N = 243 participated in the Adult Attachment Interview, which was used to assess the occurrence of abuse by parents in childhood and unresolved representations, and completed a task asking them to respond to infant cries. Sixty of the 243 participants (25% experienced childhood abuse, mostly physical or sexual. The task simulated infant temperamental difficulty by manipulating soothing success in order to reflect an easy-to-soothe (80% soothing success and a difficult-to-soothe infant (20% soothing success. Both after baseline and after each of the two stimulus series women assessed their parenting self-efficacy. Women who reported childhood abuse did not differ from women who reported no childhood abuse in parenting self-efficacy at baseline or in response to the easy-to-soothe infant (relative to baseline, but decreased more in parenting self-efficacy following the difficult-to-soothe infant. Effects did not vary according to resolution of trauma. These findings suggest that in response to infant temperamental difficulty, women who experienced childhood abuse may more easily lose confidence in their parenting abilities, which underlines the importance of preparing at-risk women for the possible challenges that come along with parenthood.

  7. High dynamic range image acquisition based on multiplex cameras

    Science.gov (United States)

    Zeng, Hairui; Sun, Huayan; Zhang, Tinghua

    2018-03-01

    High dynamic image is an important technology of photoelectric information acquisition, providing higher dynamic range and more image details, and it can better reflect the real environment, light and color information. Currently, the method of high dynamic range image synthesis based on different exposure image sequences cannot adapt to the dynamic scene. It fails to overcome the effects of moving targets, resulting in the phenomenon of ghost. Therefore, a new high dynamic range image acquisition method based on multiplex cameras system was proposed. Firstly, different exposure images sequences were captured with the camera array, using the method of derivative optical flow based on color gradient to get the deviation between images, and aligned the images. Then, the high dynamic range image fusion weighting function was established by combination of inverse camera response function and deviation between images, and was applied to generated a high dynamic range image. The experiments show that the proposed method can effectively obtain high dynamic images in dynamic scene, and achieves good results.

  8. Cooperation guided by the coexistence of imitation dynamics and aspiration dynamics in structured populations

    Science.gov (United States)

    Xu, Kuangyi; Li, Kun; Cong, Rui; Wang, Long

    2017-02-01

    In the framework of the evolutionary game theory, two fundamentally different mechanisms, the imitation process and the aspiration-driven dynamics, can be adopted by players to update their strategies. In the former case, individuals imitate the strategy of a more successful peer, while in the latter case individuals change their strategies based on a comparison of payoffs they collect in the game to their own aspiration levels. Here we explore how cooperation evolves for the coexistence of these two dynamics. Intriguingly, cooperation reaches its lowest level when a certain moderate fraction of individuals pick aspiration-level-driven rule while the others choose pairwise comparison rule. Furthermore, when individuals can adjust their update rules besides their strategies, either imitation dynamics or aspiration-driven dynamics will finally take over the entire population, and the stationary cooperation level is determined by the outcome of competition between these two dynamics. We find that appropriate synergetic effects and moderate aspiration level boost the fixation probability of aspiration-driven dynamics most effectively. Our work may be helpful in understanding the cooperative behavior induced by the coexistence of imitation dynamics and aspiration dynamics in the society.

  9. Social Support, Infant Temperament, and Parenting Self-Efficacy: A Mediational Model of Postpartum Depression

    Science.gov (United States)

    Cutrona, Carolyn E.; Troutman, Beth R.

    1986-01-01

    Infant temperamental difficulty was strongly related to mothers' level of postpartum depression, both directly and through the mediation of parenting self-efficacy. Social support appeared to function protectively against depression, primarily through self-efficacy. Practical and theoretical implications are discussed. (Author/RH)

  10. The Development of Leisure Boredom in Early Adolescence: Predictors and Longitudinal Associations with Delinquency and Depression

    Science.gov (United States)

    Spaeth, Michael; Weichold, Karina; Silbereisen, Rainer K.

    2015-01-01

    The literature proposes that leisure boredom may systematically increase during adolescence. Moreover, some authors assume that this hypothesized developmental trend is associated with increases in youthful delinquency and depression. Individual dispositions (e.g., temperamental disinhibition) are believed to exacerbate the relationship between…

  11. Equivalence of Brownian dynamics and dynamic Monte Carlo simulations in multicomponent colloidal suspensions.

    Science.gov (United States)

    Cuetos, Alejandro; Patti, Alessandro

    2015-08-01

    We propose a simple but powerful theoretical framework to quantitatively compare Brownian dynamics (BD) and dynamic Monte Carlo (DMC) simulations of multicomponent colloidal suspensions. By extending our previous study focusing on monodisperse systems of rodlike colloids, here we generalize the formalism described there to multicomponent colloidal mixtures and validate it by investigating the dynamics in isotropic and liquid crystalline phases containing spherical and rodlike particles. In order to investigate the dynamics of multicomponent colloidal systems by DMC simulations, it is key to determine the elementary time step of each species and establish a unique timescale. This is crucial to consistently study the dynamics of colloidal particles with different geometry. By analyzing the mean-square displacement, the orientation autocorrelation functions, and the self part of the van Hove correlation functions, we show that DMC simulation is a very convenient and reliable technique to describe the stochastic dynamics of any multicomponent colloidal system. Our theoretical formalism can be easily extended to any colloidal system containing size and/or shape polydisperse particles.

  12. Longitudinal beam dynamics

    International Nuclear Information System (INIS)

    Tecker, F

    2014-01-01

    The course gives a summary of longitudinal beam dynamics for both linear and circular accelerators. After discussing different types of acceleration methods and synchronism conditions, it focuses on the particle motion in synchrotrons

  13. Ansatz for dynamical hierarchies

    DEFF Research Database (Denmark)

    Rasmussen, S.; Baas, N.A.; Mayer, B.

    2001-01-01

    Complex, robust functionalities can be generated naturally in at least two ways: by the assembly of structures and by the evolution of structures. This work is concerned with spontaneous formation of structures. We define the notion of dynamical hierarchies in natural systems and show...... the importance of this particular kind of organization for living systems. We then define a framework that enables us to formulate, investigate, and manipulate such dynamical hierarchies. This framework allows us to simultaneously investigate different levels of description together with them interrelationship...... three. Formulating this system as a simple two-dimensional molecular dynamics (MD) lattice gas allows us within one dynamical system to demonstrate the successive emergence of two higher levels (three levels all together) of robust structures with associated properties. Second, we demonstrate how...

  14. Vehicle Dynamics and Control

    CERN Document Server

    Rajamani, Rajesh

    2012-01-01

    Vehicle Dynamics and Control provides a comprehensive coverage of vehicle control systems and the dynamic models used in the development of these control systems. The control system applications covered in the book include cruise control, adaptive cruise control, ABS, automated lane keeping, automated highway systems, yaw stability control, engine control, passive, active and semi-active suspensions, tire-road friction coefficient estimation, rollover prevention, and hybrid electric vehicle. In developing the dynamic model for each application, an effort is made to both keep the model simple enough for control system design but at the same time rich enough to capture the essential features of the dynamics. A special effort has been made to explain the several different tire models commonly used in literature and to interpret them physically. In the second edition of the book, chapters on roll dynamics, rollover prevention and hybrid electric vehicles have been added, and the chapter on electronic stability co...

  15. Dynamical properties for an ensemble of classical particles moving in a driven potential well with different time perturbation

    International Nuclear Information System (INIS)

    Costa, Diogo Ricardo da; Caldas, I.L.; Leonel, Edson D.

    2013-01-01

    We consider dynamical properties for an ensemble of classical particles confined to an infinite box of potential and containing a time-dependent potential well described by different nonlinear functions. For smooth functions, the phase space contains chaotic trajectories, periodic islands and invariant spanning curves preventing the unlimited particle diffusion along the energy axis. Average properties of the chaotic sea are characterised as a function of the control parameters and exponents describing their behaviour show no dependence on the perturbation functions. Given invariant spanning curves are present in the phase space, a sticky region was observed and show to modify locally the diffusion of the particles

  16. Relating coccolithophore calcification rates to phytoplankton community dynamics: Regional differences and implications for carbon export

    Science.gov (United States)

    Poulton, Alex J.; Adey, Tim R.; Balch, William M.; Holligan, Patrick M.

    2007-03-01

    Recent measurements of surface coccolithophore calcification from the Atlantic Ocean (50°N-50°S) are compared to similar measurements from other oceanic settings. By combining the different data sets of surface measurements, we examine general and regional patterns of calcification relative to organic carbon production (photosynthesis) and other characteristics of the phytoplankton community. Generally, surface calcification and photosynthesis are positively correlated, although the strength of the relationship differs between biogeochemical provinces. Relationships between surface calcification, chlorophyll- a and calcite concentrations are also statistically significant, although again there is considerable regional variability. Such variability appears unrelated to phytoplankton community composition or hydrographic conditions, and may instead reflect variations in coccolithophore physiology. The contribution of inorganic carbon fixation (calcification) to total carbon fixation (calcification plus photosynthesis) is ˜1-10%, and we estimate a similar contribution from coccolithophores to total organic carbon fixation. However, these contributions vary between biogeochemical provinces, and occasionally coccolithophores may account for >20% of total carbon fixation in unproductive central subtropical gyres. Combining surface calcification and photosynthetic rates with standing stocks of calcite, particulate organic carbon, and estimated phytoplankton carbon allows us to examine the fates of these three carbon pools. The relative turnover times vary between different biogeochemical provinces, with no clear relationship to the overall productivity or phytoplankton community structure found in each province. Rather, interaction between coccolithophore physiology (coccolith production and detachment rates), species diversity (cell size), and food web dynamics (grazer ecology) may control the composition and turnover times of calcite particles in the upper ocean.

  17. Crosslinked bicontinuous biobased PLA/NR blends via dynamic vulcanization using different curing systems.

    Science.gov (United States)

    Yuan, Daosheng; Chen, Kunling; Xu, Chuanhui; Chen, Zhonghua; Chen, Yukun

    2014-11-26

    In this study, blends of entirely biosourced polymers, namely polylactide (PLA) and natural rubber (NR), were prepared through dynamic vulcanization using dicumyl peroxide (DCP), sulphur (S) and phenolic resin (2402) as curing agents, respectively. The crosslinked NR phase was found to be a continuous structure in all the prepared blends. The molecular weight changes of PLA were studied by gel permeation chromatography. Interfacial compatibilization between PLA and NR was investigated using Fourier transform infrared spectroscopy and scanning electron microscopy. The thermal properties of blends were evaluated by differential scanning calorimetry and thermogravimetric analysis instrument. It was found that the molecular weight of PLA and interfacial compatibilizaion between PLA and NR showed a significant influence on the mechanical and thermal properties of blends. The PLA/NR blend (60/40 w/w) by DCP-induced dynamic vulcanization owned the finest mechanical properties and thermal stability. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Dynamic statistical information theory

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    capacities reflecting the dynamic dissipation characteristics in the transmission processes, which change into their maximum-the present static mutual information and static channel capacity under the limit case where the proportion of channel length to information transmission rate approaches to zero. All these unified and rigorous theoretical formulas and results are derived from the evolution equations of dynamic information and dynamic entropy without adding any extra assumption. In this review, we give an overview on the above main ideas, methods and results, and discuss the similarity and difference between two kinds of dynamic statistical information theories.

  19. Parental Involvement, Child Temperament, and Parents' Work Hours: Differential Relations for Mothers and Fathers.

    Science.gov (United States)

    Brown, Geoffrey L; McBride, Brent A; Bost, Kelly K; Shin, Nana

    2011-01-01

    This study examined how child temperament was related to parents' time spent accessible to and interacting with their 2-year-olds. Bivariate analyses indicated that both fathers and mothers spent more time with temperamentally challenging children than easier children on workdays, but fathers spent less time with challenging children than easier children on non-workdays. After accounting for work hours, some associations between temperament and fathers' workday involvement dropped to non-significance. For fathers, work hours also moderated the relation between irregular temperament and workday play. For mothers, work hours moderated the relation between both difficult and irregular temperament and workday interaction. Mothers also spent more time with girls (but not boys) who were temperamentally irregular. Results speak to the influence of child temperament on parenting behavior, and the differential construction of parenting roles as a function of child characteristics and patterns of work.

  20. Structure and dynamics of photosynthetic proteins studied by neutron scattering and molecular dynamic simulation

    International Nuclear Information System (INIS)

    Dellerue, Serge

    2000-01-01

    Understand the structure-dynamics-function relation in the case of proteins is essential. But few experimental techniques allow to have access to knowledge of fast internal movements of biological macromolecules. With the neutron scattering method, it has been possible to study the reorientation dynamics of side chains and of polypeptide skeleton for two proteins in terms of water or detergent and of temperature. With the use of the molecular dynamics method, essential for completing and interpreting the experimental data, it has been possible to assess the different contributions of the whole structure of proteins to the overall dynamics. It has been shown that the polypeptide skeleton presents an energy relaxation comparable to those of the side chains. Moreover, it has been explained that the protein dynamics can only be understood in terms of relaxation time distribution. (author) [fr

  1. 22nd International Conference on Difference Equations and Applications

    CERN Document Server

    Hamaya, Yoshihiro; Matsunaga, Hideaki; Pötzsche, Christian

    2017-01-01

    This volume contains the proceedings of the 22nd International Conference on Difference Equations and Applications, held at Osaka Prefecture University, Osaka, Japan, in July 2016. The conference brought together both experts and novices in the theory and applications of difference equations and discrete dynamical systems. The volume features papers in difference equations and discrete dynamical systems with applications to mathematical sciences and, in particular, mathematical biology and economics. This book will appeal to researchers, scientists, and educators who work in the fields of difference equations, discrete dynamical systems, and their applications.

  2. Comparisons of Different Models on Dynamic Recrystallization of Plate during Asymmetrical Shear Rolling

    Directory of Open Access Journals (Sweden)

    Tao Zhang

    2018-01-01

    Full Text Available Asymmetrical shear rolling with velocity asymmetry and geometry asymmetry is beneficial to enlarge deformation and refine grain size at the center of the thick plate compared to conventional symmetrical rolling. Dynamic recrystallization (DRX plays a vital role in grain refinement during hot deformation. Finite element models (FEM coupled with microstructure evolution models and cellular automata models (CA are established to study the microstructure evolution of plate during asymmetrical shear rolling. The results show that a larger DRX fraction and a smaller average grain size can be obtained at the lower layer of the plate. The DRX fraction at the lower part increases with the ascending speed ratio, while that at upper part decreases. With the increase of the offset distance, the DRX fraction slightly decreases for the whole thickness of the plate. The differences in the DRX fraction and average grain size between the upper and lower surfaces increase with the ascending speed ratio; however, it varies little with the change of the speed ratio. Experiments are conducted and the CA models have a higher accuracy than FEM models as the grain morphology, DRX nuclei, and grain growth are taken into consideration in CA models, which are more similar to the actual DRX process during hot deformation.

  3. Comparisons of Different Models on Dynamic Recrystallization of Plate during Asymmetrical Shear Rolling

    Science.gov (United States)

    Zhang, Tao; Li, Lei; Lu, Shi-Hong; Gong, Hai; Wu, Yun-Xin

    2018-01-01

    Asymmetrical shear rolling with velocity asymmetry and geometry asymmetry is beneficial to enlarge deformation and refine grain size at the center of the thick plate compared to conventional symmetrical rolling. Dynamic recrystallization (DRX) plays a vital role in grain refinement during hot deformation. Finite element models (FEM) coupled with microstructure evolution models and cellular automata models (CA) are established to study the microstructure evolution of plate during asymmetrical shear rolling. The results show that a larger DRX fraction and a smaller average grain size can be obtained at the lower layer of the plate. The DRX fraction at the lower part increases with the ascending speed ratio, while that at upper part decreases. With the increase of the offset distance, the DRX fraction slightly decreases for the whole thickness of the plate. The differences in the DRX fraction and average grain size between the upper and lower surfaces increase with the ascending speed ratio; however, it varies little with the change of the speed ratio. Experiments are conducted and the CA models have a higher accuracy than FEM models as the grain morphology, DRX nuclei, and grain growth are taken into consideration in CA models, which are more similar to the actual DRX process during hot deformation. PMID:29342080

  4. Robustness Analysis of Dynamic Watermarks

    Directory of Open Access Journals (Sweden)

    Ivan V. Nechta

    2017-06-01

    Full Text Available In this paper we consider previously known scheme of dynamic watermarks embedding (Ra- dix-n that is used for preventing illegal use of software. According to the scheme a watermark is dynamic linked data structure (graph, which is created in memory during program execution. Hidden data, such as information about author, can be represented in a different type of graph structure. This data can be extracted and demonstrated in judicial proceedings. This paper declared that the above mentioned scheme was previously one of the most reliable, has a number of features that allows an attacker to detect a stage of watermark construction in the program, and therefore it can be corrupted or deleted. The author of this article shows the weakness of Radix-N scheme, which consists in the fact that we can reveal dynamic data structures of a program by using information received from some API-functions hooker which catches function calls of dynamic memory allocation. One of these data structures is the watermark. Pointers on dynamically created objects (arrays, variables, class items, etc. of a program can be detected by content analysis of computer's RAM. Different dynamic objects in memory interconnected by pointers form dynamic data structures of a program such as lists, stacks, trees and other graphs (including the watermark. Our experiment shows that in the vast majority of cases the amount of data structure in programs is small, which increases probability of a successful attack. Also we present an algorithm for finding connected components of a graph with linear time-consuming in cases where the number of nodes is about 106. On the basis of the experimental findings the new watermarking scheme has been presented, which is resistant to the proposed attack. It is offered to use different graph structure representation of a watermark, where edges are implemented using unique signatures. Our scheme uses content encrypting of graph nodes (except signature

  5. Relationship between affective temperaments and aggression in euthymic patients with bipolar mood disorder and major depressive disorder.

    Science.gov (United States)

    Dolenc, B; Dernovšek, M Z; Sprah, L; Tavcar, R; Perugi, G; Akiskal, H S

    2015-03-15

    So far there is a scarce of studies dealing with the relationship between different aspects of aggressive behaviour and affective temperaments among various mood disorders. The aim of the present study was to explore in a group of patients with affective mood disorders the relationship between affective temperaments and aggression. 100 consecutive outpatients in euthymic phase of mood disorders (46 with bipolar disorder-type I, 18 with bipolar disorder-type II and 36 with major depressive disorder) were self-assessed with the Aggression Questionnaire and the short version of Slovenian Temperament Evaluation of Memphis, Pisa, Paris and San Diego - Autoquestionnaire (TEMPS-A). The factorial analysis of the TEMPS-A subscales revealed 2 main factors: Factor 1 (prominent cyclothymic profile) consisted of cyclothymic, depressive, irritable, and anxious temperaments and Factor 2 (prominent hyperthymic profile) which was represented by the hyperthymic temperament, and by depressive and anxious temperaments as negative components. Patients with prominent cyclothymic profile got their diagnosis later in their life and had significantly higher mean scores on anger and hostility (non-motor aggressive behaviour) compared with patients with prominent hyperthymic profile. We included patients with different mood disorders, therefore the sample selection may influence temperamental and aggression profiles. We used self-report questionnaires which can elicit sociable desirable answers. Anger and hostility could represent stable personality characteristics of prominent cyclothymic profile that endure even in remission. It seems that distinct temperamental profile could serve as a good diagnostic and prognostic value for non-motor aspects of aggressive behaviour. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. Investigating the applicability of Dynamic Assessment in Iran: From ...

    African Journals Online (AJOL)

    3) Teachers with different levels of education held similar and positive attitudes regarding the applicability of dynamic assessment. Key words: Assessment, Dynamic Assessment, Zone of Proximal Development, Interventionist Dynamic Assessment, Interactionist Dynamic Assessment. La présente étude visait à étudier les ...

  7. The effects of individual differences, prior experience and cognitive load on the transfer of dynamic decision-making performance.

    Science.gov (United States)

    Nicholson, Brad; O'Hare, David

    2014-01-01

    Situational awareness is recognised as an important factor in the performance of individuals and teams in dynamic decision-making (DDM) environments (Salmon et al. 2014 ). The present study was designed to investigate whether the scores on the WOMBAT™ Situational Awareness and Stress Tolerance Test (Roscoe and North 1980 ) would predict the transfer of DDM performance from training under different levels of cognitive load to a novel situation. Participants practised a simulated firefighting task under either low or high conditions of cognitive load and then performed a (transfer) test in an alternative firefighting environment under an intermediate level of cognitive load. WOMBAT™ test scores were a better predictor of DDM performance than scores on the Raven Matrices. Participants with high WOMBAT™ scores performed better regardless of their training condition. Participants with recent gaming experience who practised under low cognitive load showed better practice phase performance but worse transfer performance than those who practised under high cognitive load. The relationship between task experience, situational awareness ability, cognitive load and the transfer of dynamic decision-making (DDM) performance was investigated. Results showed that the WOMBAT™ test predicted transfer of DDM performance regardless of task cognitive load. The effects of cognitive load on performance varied according to previous task-relevant experience.

  8. Short-term Consumer Benefits of Dynamic Pricing

    OpenAIRE

    Dupont, Benjamin; De Jonghe, Cedric; Kessels, Kris; Belmans, Ronnie

    2011-01-01

    Consumer benefits of dynamic pricing depend on a variety of factors. Consumer characteristics and climatic circumstances widely differ, which forces a regional comparison. This paper presents a general overview of demand response programs and focuses on the short-term benefits of dynamic pricing for an average Flemish residential consumer. It reaches a methodology to develop a cost reflective dynamic pricing program and to estimate short-term bill savings. Participating in a dynamic pricing p...

  9. Comparing the dynamics of skyrmions and superconducting vortices

    International Nuclear Information System (INIS)

    Olson Reichhardt, C.J.; Lin, S.Z.; Ray, D.; Reichhardt, C.

    2014-01-01

    Highlights: • We describe similarities and differences between skyrmion and vortex dynamics. • The Magnus force can dramatically alter skyrmion transport. • The pinning becomes very weak when the Magnus force is strong. - Abstract: Vortices in type-II superconductors have attracted enormous attention as ideal systems in which to study nonequilibrium collective phenomena, since the self-ordering of the vortices competes with quenched disorder and thermal effects. Dynamic effects found in vortex systems include depinning, nonequilibrium phase transitions, creep, structural order–disorder transitions, and melting. Understanding vortex dynamics is also important for applications of superconductors which require the vortices either to remain pinned or to move in a controlled fashion. Recently, topological defects called skyrmions have been realized experimentally in chiral magnets. Here we highlight similarities and differences between skyrmion dynamics and vortex dynamics. Many of the previous ideas and experimental setups that have been applied to superconducting vortices can also be used to study skyrmions. We also discuss some of the differences between the two systems, such as the potentially large contribution of the Magnus force in the skyrmion system that can dramatically alter the dynamics and transport properties

  10. Dynamics, Stability, and Evolutionary Patterns of Mesoscale Intrathermocline Vortices

    Science.gov (United States)

    2016-12-01

    different manner from a dynamic eddy, which underscores inherent limitations of intrusion modeling in quiescent background states. Finally, it...of observed values. (3) A static eddy dissipates in a very different manner from a dynamic eddy, which underscores inherent limitations of...does not react to the environment in a physical manner . This establishes a need for future research on eddies to be modeled on a dynamically rotating

  11. Dynamic 31phosphorus magnetic resonance spectroscopy of the quadriceps muscle: Metabolic changes resulting from two different forms of exercise

    International Nuclear Information System (INIS)

    Schunk, K.; Kersjes, W.; Schadmand-Fischer, S.; Thelen, M.

    1997-01-01

    Purpose: The aim of the present investigation was to examine the metabolism of the quadriceps muscles of normal young individuals using dynamic 31 phosphorus magnetic resonance spectroscopy. Methods: 22 normal individuals were examined in a 1.5 T-MRT using a 6 cm surface coil. The metabolic changes in the quadriceps muscle as shown by the phosphorus spectrum were evaluated during rest, exercise (isometric and isotonic exercise) and during a 36-second period of recovery. Results: The P i /PCr quotient rose from its resting value of 0.11±0.02 following exercise to a maximum of 0.83±0.47 (isometric) or 1.40±0.59 (isotonic) (difference p=0.0001). Half-time recovery of P i /PCr was 35±11 s or 31±10 s, respectively (p=0.13). During the recovery phase P i /PCr fell briefly but significantly below its rest value. Following an initial rise in pH, there was a continual fall. Minimum pH (6.68±0.21 and 6.53±0.27 respectively; p=0.01) occurred in the early recovery phase. The recovery process of pH values lasted longer following isotonic than after isometric exercise (half-value recovery time 229±72 s and 146±55 s, respectively; p=0.001). Conlcusion: Compared with isometric exercise, isotonic stress is more expensive in terms of metabolism. Dynamic 31 phosphorus MRT spectroscopy can differentiate changes in muscle metabolism during different forms of exercise. (orig.) [de

  12. Robust transient dynamics and brain functions

    Directory of Open Access Journals (Sweden)

    Mikhail I Rabinovich

    2011-06-01

    Full Text Available In the last few decades several concepts of Dynamical Systems Theory (DST have guided psychologists, cognitive scientists, and neuroscientists to rethink about sensory motor behavior and embodied cognition. A critical step in the progress of DST application to the brain (supported by modern methods of brain imaging and multi-electrode recording techniques has been the transfer of its initial success in motor behavior to mental function, i.e., perception, emotion, and cognition. Open questions from research in genetics, ecology, brain sciences, etc. have changed DST itself and lead to the discovery of a new dynamical phenomenon, i.e., reproducible and robust transients that are at the same time sensitive to informational signals. The goal of this review is to describe a new mathematical framework -heteroclinic sequential dynamics- to understand self-organized activity in the brain that can explain certain aspects of robust itinerant behavior. Specifically, we discuss a hierarchy of coarse-grain models of mental dynamics in the form of kinetic equations of modes. These modes compete for resources at three levels: (i within the same modality, (ii among different modalities from the same family (like perception, and (iii among modalities from different families (like emotion and cognition. The analysis of the conditions for robustness, i.e., the structural stability of transient (sequential dynamics, give us the possibility to explain phenomena like the finite capacity of our sequential working memory -a vital cognitive function-, and to find specific dynamical signatures -different kinds of instabilities- of several brain functions and mental diseases.

  13. DYNAMICS OF OPIOID SUBSTITUTION TREATMENTIN DIFFERENT INITIAL SUBSTANCE USER OPIOID DEPENDENT PATIENTS.

    Science.gov (United States)

    Todadze, Kh; Mosia, S

    2016-05-01

    figures was observed in all groups in three month period that have been continuing during 21 month of treatment process. Study revealed normalization of scores forbothstatesin groups of heroine, desomorphine, methadone and buprenorphine users. The highest scores of depression and anxiety were observed in the group of poly-drug abusers andwhile depression rate hesitated in the range of clear "no-depression", anxiety index still remained close to the clinical important threshold after 21 month of treatment. Urine-testingon psychotropic-narcotic substances indicated remarkable decrease of illegal drug abuse in all studied groups in three month and although abuse of benzodiazepine drugs was highest in desomorphine and poly-drug abusers, the difference between groups was not statistically significant. Although some disparities have been observed in dynamics of subjects with different spectrum of initial opioid substance use, including homemade desomorphine, there is no significant difference between groups and OST effectively supports to improve depression and anxiety indices, and dramatically decreases use of illegal psychotropic-narcotic drugs during treatment. However poly-drug users seems to be the most resistant to achieve stabilization and require more treatment time and targeted interventions.

  14. Dynamic Analysis of Planar 3-RRR Flexible Parallel Robots with Dynamic Stiffening

    Directory of Open Access Journals (Sweden)

    Qinghua Zhang

    2014-01-01

    Full Text Available In consideration of the second-order coupling quantity of the axial displacement caused by the transverse displacement of flexible beam, the first-order approximation coupling model of planar 3-RRR flexible parallel robots is presented, in which the rigid body motion constraints, elastic deformation motion constraints, and dynamic constraints of the moving platform are considered. Based on the different speed of the moving platform, numerical simulation results using the conventional zero-order approximation coupling model and the proposed firstorder approximation coupling model show that the effect of “dynamic stiffening” term on dynamic characteristics of the system is insignificant and can be neglected, and the zero-order approximation coupling model is enough precisely for catching essentially dynamic characteristics of the system. Then, the commercial software ANSYS 13.0 is used to confirm the validity of the zero-order approximation coupling model.

  15. Nonlinear dynamics of the magnetosphere and space weather

    Science.gov (United States)

    Sharma, A. Surjalal

    1996-01-01

    The solar wind-magnetosphere system exhibits coherence on the global scale and such behavior can arise from nonlinearity on the dynamics. The observational time series data were used together with phase space reconstruction techniques to analyze the magnetospheric dynamics. Analysis of the solar wind, auroral electrojet and Dst indices showed low dimensionality of the dynamics and accurate prediction can be made with an input/output model. The predictability of the magnetosphere in spite of the apparent complexity arises from its dynamical synchronism with the solar wind. The electrodynamic coupling between different regions of the magnetosphere yields its coherent, low dimensional behavior. The data from multiple satellites and ground stations can be used to develop a spatio-temporal model that identifies the coupling between different regions. These nonlinear dynamical models provide space weather forecasting capabilities.

  16. Nonlinear dynamics based digital logic and circuits.

    Science.gov (United States)

    Kia, Behnam; Lindner, John F; Ditto, William L

    2015-01-01

    We discuss the role and importance of dynamics in the brain and biological neural networks and argue that dynamics is one of the main missing elements in conventional Boolean logic and circuits. We summarize a simple dynamics based computing method, and categorize different techniques that we have introduced to realize logic, functionality, and programmability. We discuss the role and importance of coupled dynamics in networks of biological excitable cells, and then review our simple coupled dynamics based method for computing. In this paper, for the first time, we show how dynamics can be used and programmed to implement computation in any given base, including but not limited to base two.

  17. Toward Greater Specificity in Identifying Associations among Interparental Aggression, Child Emotional Reactivity to Conflict, and Child Problems

    Science.gov (United States)

    Davies, Patrick T.; Cicchetti, Dante; Martin, Meredith J.

    2012-01-01

    This study examined specific forms of emotional reactivity to conflict and temperamental emotionality as explanatory mechanisms in pathways among interparental aggression and child psychological problems. Participants of the multimethod, longitudinal study included 201 two-year-old children and their mothers who had experienced elevated violence…

  18. Differential Susceptibility to the Environment: Are Developmental Models Compatible with the Evidence from Twin Studies?

    Science.gov (United States)

    Del Giudice, Marco

    2016-01-01

    According to models of differential susceptibility, the same neurobiological and temperamental traits that determine increased sensitivity to stress and adversity also confer enhanced responsivity to the positive aspects of the environment. Differential susceptibility models have expanded to include complex developmental processes in which genetic…

  19. Parenting Self-Efficacy Predicts Perceptions of Infant Negative Temperament Characteristics, Not Vice Versa

    NARCIS (Netherlands)

    Verhage, M.L.; Oosterman, M.; Schuengel, C.

    2013-01-01

    Infant temperamental characteristics have been found associated with decreasing parenting self-efficacy(PSE) during the first year after birth, which has been generally interpreted as a child effect on the parent.To test direction of effects, PSE was assessed during the third trimester of pregnancy

  20. The importance of shared environment in infant-father attachment: A behavioral genetic study of the Attachment Q-Sort

    NARCIS (Netherlands)

    Bakermans-Kranenburg, M.J.; van IJzendoorn, M.H.; Bokhorst, C.L.; Schuengel, C.

    2004-01-01

    In this first behavior genetic study on infant-father attachment, we estimated genetic and environmental influences on infant-father attachment behaviors and on temperamental dependency, both assessed with the Attachment Q-Sort (AQS; B. E.Vaughn & E. Waters, 1990; E. Waters, 1995). Mothers of mono-

  1. Are Cognitive Control and Stimulus-Driven Processes Differentially Linked to Inattention and Hyperactivity in Preschoolers?

    Science.gov (United States)

    Miller, Carlin J.; Miller, Scott R.; Healey, Dione M.; Marshall, Katie; Halperin, Jeffrey M.

    2013-01-01

    Temperament and attention-deficit/hyperactivity disorder (ADHD) are both typically viewed as biologically based behavioural constructs. There is substantial overlap between ADHD symptoms and specific temperamental traits, such as effortful control, especially in young children. Recent work by Martel and colleagues (2009, 2011) suggests that…

  2. Value dynamics and infrastructure reform

    DEFF Research Database (Denmark)

    Beck Jørgensen, Torben

    2009-01-01

    varying decision making contexts bear on the role of values and the handling of values. A number of theoretical explanations of value change are presented, from teleological explanations to pendulum dynamics and life cycle theories. The paper concludes with suggestions on how to deal with normative......This paper identifies the aspects of value dynamics in each of the previous papers: how the choice of institutional arrangements give primacy to some values and others not; the law and the market as separate dynamic forces; the different time horizons involved when studying value changes; and how...

  3. Chaos crisis in coupled Duffing's systems with initial phase difference

    International Nuclear Information System (INIS)

    Bi Qinsheng

    2007-01-01

    The dynamics of coupled Duffing's oscillators with initial phase difference is investigated in this Letter. For the averaged equations, different equilibrium points can be observed, the number of which may vary with the parameters. The stable equilibrium points, corresponding to the periodic motion of the original coupled oscillators, may coexist with different patterns of dynamics, including chaos. Furthermore, two different chaotic attractors associated with different attracting basin coexist for certain parameter conditions, which may interact with each other to form an enlarged chaotic attractor. Several new dynamical phenomena such as boundary chaos crises have been predicted as the initial phase difference varies

  4. Nonlinear analysis of pupillary dynamics.

    Science.gov (United States)

    Onorati, Francesco; Mainardi, Luca Tommaso; Sirca, Fabiola; Russo, Vincenzo; Barbieri, Riccardo

    2016-02-01

    Pupil size reflects autonomic response to different environmental and behavioral stimuli, and its dynamics have been linked to other autonomic correlates such as cardiac and respiratory rhythms. The aim of this study is to assess the nonlinear characteristics of pupil size of 25 normal subjects who participated in a psychophysiological experimental protocol with four experimental conditions, namely “baseline”, “anger”, “joy”, and “sadness”. Nonlinear measures, such as sample entropy, correlation dimension, and largest Lyapunov exponent, were computed on reconstructed signals of spontaneous fluctuations of pupil dilation. Nonparametric statistical tests were performed on surrogate data to verify that the nonlinear measures are an intrinsic characteristic of the signals. We then developed and applied a piecewise linear regression model to detrended fluctuation analysis (DFA). Two joinpoints and three scaling intervals were identified: slope α0, at slow time scales, represents a persistent nonstationary long-range correlation, whereas α1 and α2, at middle and fast time scales, respectively, represent long-range power-law correlations, similarly to DFA applied to heart rate variability signals. Of the computed complexity measures, α0 showed statistically significant differences among experimental conditions (pnonlinear dynamics, (b) three well-defined and distinct long-memory processes exist at different time scales, and (c) autonomic stimulation is partially reflected in nonlinear dynamics. (c) autonomic stimulation is partially reflected in nonlinear dynamics.

  5. Dynamical systems in population biology

    CERN Document Server

    Zhao, Xiao-Qiang

    2017-01-01

    This research monograph provides an introduction to the theory of nonautonomous semiflows with applications to population dynamics. It develops dynamical system approaches to various evolutionary equations such as difference, ordinary, functional, and partial differential equations, and pays more attention to periodic and almost periodic phenomena. The presentation includes persistence theory, monotone dynamics, periodic and almost periodic semiflows, basic reproduction ratios, traveling waves, and global analysis of prototypical population models in ecology and epidemiology. Research mathematicians working with nonlinear dynamics, particularly those interested in applications to biology, will find this book useful. It may also be used as a textbook or as supplementary reading for a graduate special topics course on the theory and applications of dynamical systems. Dr. Xiao-Qiang Zhao is a University Research Professor at Memorial University of Newfoundland, Canada. His main research interests involve applied...

  6. Geometry Dynamics of α-Helices in Different Class I Major Histocompatibility Complexes

    Directory of Open Access Journals (Sweden)

    Reiner Ribarics

    2015-01-01

    Full Text Available MHC α-helices form the antigen-binding cleft and are of particular interest for immunological reactions. To monitor these helices in molecular dynamics simulations, we applied a parsimonious fragment-fitting method to trace the axes of the α-helices. Each resulting axis was fitted by polynomials in a least-squares sense and the curvature integral was computed. To find the appropriate polynomial degree, the method was tested on two artificially modelled helices, one performing a bending movement and another a hinge movement. We found that second-order polynomials retrieve predefined parameters of helical motion with minimal relative error. From MD simulations we selected those parts of α-helices that were stable and also close to the TCR/MHC interface. We monitored the curvature integral, generated a ruled surface between the two MHC α-helices, and computed interhelical area and surface torsion, as they changed over time. We found that MHC α-helices undergo rapid but small changes in conformation. The curvature integral of helices proved to be a sensitive measure, which was closely related to changes in shape over time as confirmed by RMSD analysis. We speculate that small changes in the conformation of individual MHC α-helices are part of the intrinsic dynamics induced by engagement with the TCR.

  7. Dynamical Heterogeneity in Granular Fluids and Structural Glasses

    Science.gov (United States)

    Avila, Karina E.

    Our current understanding of the dynamics of supercooled liquids and other similar slowly evolving (glassy) systems is rather limited. One aspect that is particularly poorly understood is the origin and behavior of the strong non trivial fluctuations that appear in the relaxation process toward equilibrium. Glassy systems and granular systems both present regions of particles moving cooperatively and at different rates from other regions. This phenomenon is known as spatially heterogeneous dynamics. A detailed explanation of this phenomenon may lead to a better understanding of the slow relaxation process, and perhaps it could even help to explain the presence of the glass transition. This dissertation concentrates on studying dynamical heterogeneity by analyzing simulation data for models of granular materials and structural glasses. For dissipative granular fluids, the growing behavior of dynamical heterogeneities is studied for different densities and different degrees of inelasticity in the particle collisions. The correlated regions are found to grow rapidly as the system approaches dynamical arrest. Their geometry is conserved even when probing at different cutoff length in the correlation function or when the energy dissipation in the system is increased. For structural glasses, I test a theoretical framework that models dynamical heterogeneity as originated in the presence of Goldstone modes, which emerge from a broken continuous time reparametrization symmetry. This analysis is based on quantifying the size and the spatial correlations of fluctuations in the time variable and of other kinds of fluctuations. The results obtained here agree with the predictions of the hypothesis. In particular, the fluctuations associated to the time reparametrization invariance become stronger for low temperatures, long timescales, and large coarse graining lengths. Overall, this research points to dynamical heterogeneity to be described for granular systems similarly than

  8. Cdc42 and RhoA reveal different spatio-temporal dynamics upon local stimulation with Semaphorin-3A

    Directory of Open Access Journals (Sweden)

    Federico eIseppon

    2015-08-01

    Full Text Available Small RhoGTPases, such as Cdc42 and RhoA, are key players in integrating external cues and intracellular signaling pathways that regulate growth cone (GC motility. Indeed, Cdc42 is involved in actin polymerization and filopodia formation, whereas RhoA induces GC collapse and neurite retraction through actomyosin contraction. In this study we employed Förster Resonance Energy Transfer (FRET microscopy to study the spatio-temporal dynamics of Cdc42 and RhoA in GCs in response to local Semaphorin-3A stimulation obtained with lipid vesicles filled with Semaphorin-3A and positioned near the selected GC using optical tweezers. We found that Cdc42 and RhoA were activated at the leading edge of NG108-15 neuroblastoma cells during spontaneous cycles of protrusion and retraction, respectively. The release of Semaphorin-3A brought to a progressive activation of RhoA within 30 seconds from the stimulus in the central region of the GC that collapsed and retracted. In contrast, the same stimulation evoked waves of Cdc42 activation propagating away from the stimulated region. A more localized stimulation obtained with Sema3A coated beads placed on the GC, led to Cdc42 active waves that propagated in a retrograde manner with a mean period of 70 seconds, and followed by GC retraction. Therefore, Semaphorin-3A activates both Cdc42 and RhoA with a complex and different spatial-temporal dynamics.

  9. Binding mechanism and dynamic conformational change of C subunit of PKA with different pathways.

    Science.gov (United States)

    Chu, Wen-Ting; Chu, Xiakun; Wang, Jin

    2017-09-19

    The catalytic subunit of PKA (PKAc) exhibits three major conformational states (open, intermediate, and closed) during the biocatalysis process. Both ATP and substrate/inhibitor can effectively induce the conformational changes of PKAc from open to closed states. Aiming to explore the mechanism of this allosteric regulation, we developed a coarse-grained model and analyzed the dynamics of conformational changes of PKAc during binding by performing molecular dynamics simulations for apo PKAc, binary PKAc (PKAc with ATP, PKAc with PKI), and ternary PKAc (PKAc with ATP and PKI). Our results suggest a mixed binding mechanism of induced fit and conformational selection, with the induced fit dominant. The ligands can drive the movements of Gly-rich loop as well as some regions distal to the active site in PKAc and stabilize them at complex state. In addition, there are two parallel pathways (pathway with PKAc-ATP as an intermediate and pathway PKAc-PKI as an intermediate) during the transition from open to closed states. By molecular dynamics simulations and rate constant analyses, we find that the pathway through PKAc-ATP intermediate is the main binding route from open to closed state because of the fact that the bound PKI will hamper ATP from successful binding and significantly increase the barrier for the second binding subprocess. These findings will provide fundamental insights of the mechanisms of PKAc conformational change upon binding.

  10. Hamiltonian-Driven Adaptive Dynamic Programming for Continuous Nonlinear Dynamical Systems.

    Science.gov (United States)

    Yang, Yongliang; Wunsch, Donald; Yin, Yixin

    2017-08-01

    This paper presents a Hamiltonian-driven framework of adaptive dynamic programming (ADP) for continuous time nonlinear systems, which consists of evaluation of an admissible control, comparison between two different admissible policies with respect to the corresponding the performance function, and the performance improvement of an admissible control. It is showed that the Hamiltonian can serve as the temporal difference for continuous-time systems. In the Hamiltonian-driven ADP, the critic network is trained to output the value gradient. Then, the inner product between the critic and the system dynamics produces the value derivative. Under some conditions, the minimization of the Hamiltonian functional is equivalent to the value function approximation. An iterative algorithm starting from an arbitrary admissible control is presented for the optimal control approximation with its convergence proof. The implementation is accomplished by a neural network approximation. Two simulation studies demonstrate the effectiveness of Hamiltonian-driven ADP.

  11. The effect of different evapotranspiration methods on portraying soil water dynamics and ET partitioning in a semi-arid environment in Northwest China

    OpenAIRE

    Yu, L.; Zeng, Yijian; Su, Zhongbo; Cai, H.; Zheng, Z.

    2016-01-01

    Different methods for assessing evapotranspiration (ET) can significantly affect the performance of land surface models in portraying soil water dynamics and ET partitioning. An accurate understanding of the impact a method has is crucial to determining the effectiveness of an irrigation scheme. Two ET methods are discussed: one is based on reference crop evapotranspiration (ET0) theory, uses leaf area index (LAI) for partitioning into soil evaporation and transpiration, and...

  12. Multibody system dynamics, robotics and control

    CERN Document Server

    Gerstmayr, Johannes

    2013-01-01

    The volume contains 19 contributions by international experts in the field of multibody system dynamics, robotics and control. The book aims to bridge the gap between the modeling of mechanical systems by means of multibody dynamics formulations and robotics. In the classical approach, a multibody dynamics model contains a very high level of detail, however, the application of such models to robotics or control is usually limited. The papers aim to connect the different scientific communities in multibody dynamics, robotics and control. Main topics are flexible multibody systems, humanoid robots, elastic robots, nonlinear control, optimal path planning, and identification.

  13. Distinctive Dynamic Capabilities for New Business Creation

    DEFF Research Database (Denmark)

    Rosenø, Axel; Enkel, Ellen; Mezger, Florian

    2013-01-01

    This study examines the distinctive dynamic capabilities for new business creation in established companies. We argue that these are very different from those for managing incremental innovation within a company's core business. We also propose that such capabilities are needed in both slow...... and fast-paced industries, and that similarities exist across industries. Hence, the study contributes to dynamic capabilities literature by: 1) identifying the distinctive dynamic capabilities for new business creation; 2) shifting focus away from dynamic capabilities in environments characterised by high...... clock-speed and uncertainty towards considering dynamic capabilities for the purpose of developing new businesses, which also implies a high degree of uncertainty. Based on interviews with 33 companies, we identify distinctive dynamic capabilities for new business creation, find that dynamic...

  14. A qrr noncoding RNA deploys four different regulatory mechanisms to optimize quorum-sensing dynamics.

    Science.gov (United States)

    Feng, Lihui; Rutherford, Steven T; Papenfort, Kai; Bagert, John D; van Kessel, Julia C; Tirrell, David A; Wingreen, Ned S; Bassler, Bonnie L

    2015-01-15

    Quorum sensing is a cell-cell communication process that bacteria use to transition between individual and social lifestyles. In vibrios, homologous small RNAs called the Qrr sRNAs function at the center of quorum-sensing pathways. The Qrr sRNAs regulate multiple mRNA targets including those encoding the quorum-sensing regulatory components luxR, luxO, luxM, and aphA. We show that a representative Qrr, Qrr3, uses four distinct mechanisms to control its particular targets: the Qrr3 sRNA represses luxR through catalytic degradation, represses luxM through coupled degradation, represses luxO through sequestration, and activates aphA by revealing the ribosome binding site while the sRNA itself is degraded. Qrr3 forms different base-pairing interactions with each mRNA target, and the particular pairing strategy determines which regulatory mechanism occurs. Combined mathematical modeling and experiments show that the specific Qrr regulatory mechanism employed governs the potency, dynamics, and competition of target mRNA regulation, which in turn, defines the overall quorum-sensing response. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Applied dynamics

    CERN Document Server

    Schiehlen, Werner

    2014-01-01

    Applied Dynamics is an important branch of engineering mechanics widely applied to mechanical and automotive engineering, aerospace and biomechanics as well as control engineering and mechatronics. The computational methods presented are based on common fundamentals. For this purpose analytical mechanics turns out to be very useful where D’Alembert’s principle in the Lagrangian formulation proves to be most efficient. The method of multibody systems, finite element systems and continuous systems are treated consistently. Thus, students get a much better understanding of dynamical phenomena, and engineers in design and development departments using computer codes may check the results more easily by choosing models of different complexity for vibration and stress analysis.

  16. Assessing nitrification and denitrification in a paddy soil with different water dynamics and applied liquid cattle waste using the {sup 15}N isotopic technique

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Sheng, E-mail: jszs@cc.tuat.ac.jp [Institute of Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Naka-cho, Koganei, Tokyo 184-8588 (Japan); Eco-environmental Protection Institute, Shanghai Academy of Agricultural Sciences, 1000 Jinqi Road, Shanghai 201403 (China); Sakiyama, Yukina; Riya, Shohei [Graduate School of Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Naka-cho, Koganei, Tokyo 184-8588 (Japan); Song, Xiangfu [Eco-environmental Protection Institute, Shanghai Academy of Agricultural Sciences, 1000 Jinqi Road, Shanghai 201403 (China); Terada, Akihiko; Hosomi, Masaaki [Institute of Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Naka-cho, Koganei, Tokyo 184-8588 (Japan)

    2012-07-15

    Using livestock wastewater for rice production in paddy fields can remove nitrogen and supplement the use of chemical fertilizers. However, paddy fields have complicated water dynamics owing to varying characteristics and would influence nitrogen removal through nitrification followed by denitrification. Quantification of nitrification and denitrification is of great importance in assessing the influence of water dynamics on nitrogen removal in paddy fields. In this study, nitrification and nitrate reduction rates with different water dynamics after liquid cattle waste application were evaluated, and the in situ denitrification rate was determined directly using the {sup 15}N isotopic technique in a laboratory experiment. A significant linear regression correlation between nitrification and the nitrate reduction rate was observed and showed different regression coefficients under different water dynamics. The regression coefficient in the continuously flooded paddy soil was higher than in the drained-reflooded paddy soil, suggesting that nitrate would be consumed faster in the flooded paddy soil. However, nitrification was limited and the maximum rate was only 13.3 {mu}g N g{sup -1} day{sup -1} in the flooded paddy soil with rice plants, which limited the supply of nitrate. In contrast, the drained-reflooded paddy soil had an enhanced nitrification rate up to 56.8 {mu}g N g{sup -1} day{sup -1}, which was four times higher than the flooded paddy soil and further stimulated nitrate reduction rates. Correspondingly, the in situ denitrification rates determined directly in the drained-reflooded paddy soil ranged from 5 to 1035 mg N m{sup -2} day{sup -1}, which was higher than the continuously flooded paddy soil (from 5 to 318 mg N m{sup -2} day{sup -1}) during the vegetation period. The nitrogen removal through denitrification accounted for 38.9% and 9.9% of applied nitrogen in the drained-reflooded paddy soil and continuously flooded paddy soil, respectively

  17. Discrete dynamics versus analytic dynamics

    DEFF Research Database (Denmark)

    Toxværd, Søren

    2014-01-01

    For discrete classical Molecular dynamics obtained by the “Verlet” algorithm (VA) with the time increment h there exists a shadow Hamiltonian H˜ with energy E˜(h) , for which the discrete particle positions lie on the analytic trajectories for H˜ . Here, we proof that there, independent...... of such an analytic analogy, exists an exact hidden energy invariance E * for VA dynamics. The fact that the discrete VA dynamics has the same invariances as Newtonian dynamics raises the question, which of the formulations that are correct, or alternatively, the most appropriate formulation of classical dynamics....... In this context the relation between the discrete VA dynamics and the (general) discrete dynamics investigated by Lee [Phys. Lett. B122, 217 (1983)] is presented and discussed....

  18. Approaches to Learning to Control Dynamic Uncertainty

    Directory of Open Access Journals (Sweden)

    Magda Osman

    2015-10-01

    Full Text Available In dynamic environments, when faced with a choice of which learning strategy to adopt, do people choose to mostly explore (maximizing their long term gains or exploit (maximizing their short term gains? More to the point, how does this choice of learning strategy influence one’s later ability to control the environment? In the present study, we explore whether people’s self-reported learning strategies and levels of arousal (i.e., surprise, stress correspond to performance measures of controlling a Highly Uncertain or Moderately Uncertain dynamic environment. Generally, self-reports suggest a preference for exploring the environment to begin with. After which, those in the Highly Uncertain environment generally indicated they exploited more than those in the Moderately Uncertain environment; this difference did not impact on performance on later tests of people’s ability to control the dynamic environment. Levels of arousal were also differentially associated with the uncertainty of the environment. Going beyond behavioral data, our model of dynamic decision-making revealed that, in actual fact, there was no difference in exploitation levels between those in the highly uncertain or moderately uncertain environments, but there were differences based on sensitivity to negative reinforcement. We consider the implications of our findings with respect to learning and strategic approaches to controlling dynamic uncertainty.

  19. Cluster analysis of word frequency dynamics

    Science.gov (United States)

    Maslennikova, Yu S.; Bochkarev, V. V.; Belashova, I. A.

    2015-01-01

    This paper describes the analysis and modelling of word usage frequency time series. During one of previous studies, an assumption was put forward that all word usage frequencies have uniform dynamics approaching the shape of a Gaussian function. This assumption can be checked using the frequency dictionaries of the Google Books Ngram database. This database includes 5.2 million books published between 1500 and 2008. The corpus contains over 500 billion words in American English, British English, French, German, Spanish, Russian, Hebrew, and Chinese. We clustered time series of word usage frequencies using a Kohonen neural network. The similarity between input vectors was estimated using several algorithms. As a result of the neural network training procedure, more than ten different forms of time series were found. They describe the dynamics of word usage frequencies from birth to death of individual words. Different groups of word forms were found to have different dynamics of word usage frequency variations.

  20. Cluster analysis of word frequency dynamics

    International Nuclear Information System (INIS)

    Maslennikova, Yu S; Bochkarev, V V; Belashova, I A

    2015-01-01

    This paper describes the analysis and modelling of word usage frequency time series. During one of previous studies, an assumption was put forward that all word usage frequencies have uniform dynamics approaching the shape of a Gaussian function. This assumption can be checked using the frequency dictionaries of the Google Books Ngram database. This database includes 5.2 million books published between 1500 and 2008. The corpus contains over 500 billion words in American English, British English, French, German, Spanish, Russian, Hebrew, and Chinese. We clustered time series of word usage frequencies using a Kohonen neural network. The similarity between input vectors was estimated using several algorithms. As a result of the neural network training procedure, more than ten different forms of time series were found. They describe the dynamics of word usage frequencies from birth to death of individual words. Different groups of word forms were found to have different dynamics of word usage frequency variations

  1. Dynamics of aesthetic appreciation

    Science.gov (United States)

    Carbon, Claus-Christian

    2012-03-01

    Aesthetic appreciation is a complex cognitive processing with inherent aspects of cold as well as hot cognition. Research from the last decades of empirical has shown that evaluations of aesthetic appreciation are highly reliable. Most frequently, facial attractiveness was used as the corner case for investigating aesthetic appreciation. Evaluating facial attractiveness shows indeed high internal consistencies and impressively high inter-rater reliabilities, even across cultures. Although this indicates general and stable mechanisms underlying aesthetic appreciation, it is also obvious that our taste for specific objects changes dynamically. Aesthetic appreciation on artificial object categories, such as fashion, design or art is inherently very dynamic. Gaining insights into the cognitive mechanisms that trigger and enable corresponding changes of aesthetic appreciation is of particular interest for research as this will provide possibilities to modeling aesthetic appreciation for longer durations and from a dynamic perspective. The present paper refers to a recent two-step model ("the dynamical two-step-model of aesthetic appreciation"), dynamically adapting itself, which accounts for typical dynamics of aesthetic appreciation found in different research areas such as art history, philosophy and psychology. The first step assumes singular creative sources creating and establishing innovative material towards which, in a second step, people adapt by integrating it into their visual habits. This inherently leads to dynamic changes of the beholders' aesthetic appreciation.

  2. Dynamic combinatorial libraries based on hydrogen-bonde molecular boxes

    NARCIS (Netherlands)

    Kerckhoffs, J.M.C.A.; Mateos timoneda, Miguel; Reinhoudt, David; Crego Calama, Mercedes

    2007-01-01

    This article describes two different types of dynamic combinatorial libraries of host and guest molecules. The first part of this article describes the encapsulation of alizarin trimer 2 a3 by dynamic mixtures of up to twenty different self-assembled molecular receptors together with the

  3. Attention Biases to Threat Link Behavioral Inhibition to Social Withdrawal over Time in Very Young Children

    Science.gov (United States)

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

    2011-01-01

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

  4. Associations among Context-Specific Maternal Protective Behavior, Toddlers' Fearful Temperament, and Maternal Accuracy and Goals

    Science.gov (United States)

    Kiel, Elizabeth J.; Buss, Kristin A.

    2012-01-01

    Maternal protective responses to temperamentally fearful toddlers have previously been found to relate to increased risk for children's development of anxiety-spectrum problems. Not all protective behavior is "overprotective", and not all mothers respond to toddlers' fear with protection. Therefore, the current study aimed to identify conditions…

  5. Early Temperament and Attachment Security with Mothers and Fathers as Predictors of Toddler Compliance and Noncompliance

    Science.gov (United States)

    Lickenbrock, Diane M.; Braungart-Rieker, Julia M.; Ekas, Naomi V.; Zentall, Shannon R.; Oshio, Toko; Planalp, Elizabeth M.

    2013-01-01

    This longitudinal study (n?=?106) examined associations between temperament, attachment, and styles of compliance and noncompliance. Infant negative temperamental reactivity was reported by mothers at 3, 5 and 7?months. Infant attachment was assessed (Strange Situation) at 12 (mothers) and 14?months (fathers). Toddlers' styles of…

  6. Community Screening for Preschool Child Inhibition to Offer the "Cool Little Kids" Anxiety Prevention Programme

    Science.gov (United States)

    Beatson, Ruth M.; Bayer, Jordana K.; Perry, Alexandra; Mathers, Megan; Hiscock, Harriet; Wake, Melissa; Beesley, Kate; Rapee, Ronald M.

    2014-01-01

    Temperamental inhibition has been identified as a key risk factor for childhood anxiety and internalizing problems. An efficacious early prevention programme for shy/inhibited children has been developed; however, accurate, efficient and acceptable screening is needed to support wider implementation. We explore community screening options in the…

  7. Affective and Behavioral Features of Jealousy Protest: Associations with Child Temperament, Maternal Interaction Style, and Attachment

    Science.gov (United States)

    Hart, Sybil L.; Behrens, Kazuko Y.

    2013-01-01

    This study explored variation in affective and behavioral components of infants' jealousy protests during an eliciting condition in which mother and an experimenter directed differential attention exclusively toward a rival. Variation was examined in relation to child temperamental emotionality, maternal interaction style, and attachment security.…

  8. Temperament, disordered attachment and parental sensitivity in foster care: Differential findings on attachment security for shy children

    NARCIS (Netherlands)

    de Schipper, J.C.; Oosterman, M.; Schuengel, C.

    2012-01-01

    In a foster care sample, the moderating effect of temperamental shyness on the association between parental sensitivity and attachment quality was tested. The foster parents of 59 foster children (age M=57 months, SD=16.4) filled out the Child Behavior Questionnaire. To control for confounds,

  9. Mental Health Concerns in Williams Syndrome: Intervention Considerations and Illustrations from Case Examples

    Science.gov (United States)

    Phillips, Kristin D.; Klein-Tasman, Bonita P.

    2009-01-01

    The refinement of the Williams syndrome phenotype has frequently included the study of behavioral and temperamental features common to individuals with this disorder. Within this line of research, the importance of evaluating incidence of psychopathology has been increasingly recognized, with studies consistently identifying an increased risk for…

  10. Temperament and Personality Theory: The Perspective of Cognitive-Experiential Self-Theory.

    Science.gov (United States)

    Teglasi, Hedwig; Epstein, Seymour

    1998-01-01

    Illustrates the applicability of temperamental constructs to personality theory by mapping key temperament constructs onto Cognitive-Experiential Self-Theory (CEST). Examines the role of temperament in shaping experiences, and looks at the implications for education and socialization that stem from the synthesis of temperament constructs and…

  11. Difficult Temperament, Parental Relationships, and Adolescent Alcohol Use Disorder Symptoms.

    Science.gov (United States)

    Neighbors, Bryan D.; Clark, Duncan B.; Donovan, John E.; Brody, Gene H.

    2000-01-01

    Study tested the hypothesis that the quality of the parent-adolescent relationship mediates the association between difficult temperament and alcohol use disorder (AUD) symptoms. Results suggest that alcohol abuse prevention and treatment programs should consider the role of basic temperamental characteristics in pathological drinking, and the…

  12. Nonlinear dynamics in biological systems

    CERN Document Server

    Carballido-Landeira, Jorge

    2016-01-01

    This book presents recent research results relating to applications of nonlinear dynamics, focusing specifically on four topics of wide interest: heart dynamics, DNA/RNA, cell mobility, and proteins. The book derives from the First BCAM Workshop on Nonlinear Dynamics in Biological Systems, held in June 2014 at the Basque Center of Applied Mathematics (BCAM). At this international meeting, researchers from different but complementary backgrounds, including molecular dynamics, physical chemistry, bio-informatics and biophysics, presented their most recent results and discussed the future direction of their studies using theoretical, mathematical modeling and experimental approaches. Such was the level of interest stimulated that the decision was taken to produce this publication, with the organizers of the event acting as editors. All of the contributing authors are researchers working on diverse biological problems that can be approached using nonlinear dynamics. The book will appeal especially to applied math...

  13. Network dynamics in the healthy and epileptic developing brain

    Directory of Open Access Journals (Sweden)

    Richard Rosch

    2018-03-01

    Full Text Available Electroencephalography (EEG allows recording of cortical activity at high temporal resolution. EEG recordings can be summarized along different dimensions using network-level quantitative measures, such as channel-to-channel correlation, or band power distributions across channels. These reveal network patterns that unfold over a range of different timescales and can be tracked dynamically. Here we describe the dynamics of network state transitions in EEG recordings of spontaneous brain activity in normally developing infants and infants with severe early infantile epileptic encephalopathies (n = 8, age: 1–8 months. We describe differences in measures of EEG dynamics derived from band power, and correlation-based summaries of network-wide brain activity. We further show that EEGs from different patient groups and controls may be distinguishable on a small set of the novel quantitative measures introduced here, which describe dynamic network state switching. Quantitative measures related to the sharpness of switching from one correlation pattern to another show the largest differences between groups. These findings reveal that the early epileptic encephalopathies are associated with characteristic dynamic features at the network level. Quantitative network-based analyses like the one presented here may in the future inform the clinical use of quantitative EEG for diagnosis.

  14. Forest dynamics.

    Science.gov (United States)

    Frelich, Lee

    2016-01-01

    Forest dynamics encompass changes in stand structure, species composition, and species interactions with disturbance and environment over a range of spatial and temporal scales. For convenience, spatial scale is defined as individual tree, neighborhood, stand, and landscape. Whether a given canopy-leveling disturbance will initiate a sequence of development in structure with little change in composition or initiate an episode of succession depends on a match or mismatch, respectively, with traits of the dominant tree species that allow the species to survive disturbance. When these match, certain species-disturbance type combinations lock in a pattern of stand and landscape dynamics that can persist for several generations of trees; thus, dominant tree species regulate, as well as respond to, disturbance. A complex interaction among tree species, neighborhood effects, disturbance type and severity, landform, and soils determines how stands of differing composition form and the mosaic of stands that compose the landscape. Neighborhood effects (e.g., serotinous seed rain, sprouting, shading, leaf-litter chemistry, and leaf-litter physical properties) operate at small spatial extents of the individual tree and its neighbors but play a central role in forest dynamics by contributing to patch formation at stand scales and dynamics of the entire landscape. Dominance by tree species with neutral to negative neighborhood effects leads to unstable landscape dynamics in disturbance-prone regions, wherein most stands are undergoing succession; stability can only occur under very low-severity disturbance regimes. Dominance by species with positive effects leads to stable landscape dynamics wherein only a small proportion of stands undergo succession at any one time. Positive neighborhood effects are common in temperate and boreal zones, whereas negative effects are more common in tropical climates. Landscapes with positive dynamics have alternate categories of dynamics

  15. Dynamic CT of hepatocellular carcinoma

    International Nuclear Information System (INIS)

    Fujita, Nobuyuki; Shirato, Hiroki; Shinohara, Masahiro; Miyasaka, Kazuo; Morita, Yutaka; Irie, Goro

    1983-01-01

    We performed dynamic CT in 30 cases of hepatocellular carcinoma, and concluded as below. 1 Decting the stain in the early phase of the dynamic series, it is possible to make a diagnosis of hepatocellular carcinoma. 2 The dinamic CT is effective in a case of small hepatocellular carcinoma in which it is difficult to gain an accurate diagnosis in the routine CT study. 3 The dynamic CT is also effective in the differential diagnosis of hepatic lesions, as other hepatic lesions such as hemangioma and metastatic liver cancer show different patterns compared with hepatocellular carcinoma. (author)

  16. Dislocation Dynamics During Plastic Deformation

    CERN Document Server

    Messerschmidt, Ulrich

    2010-01-01

    The book gives an overview of the dynamic behavior of dislocations and its relation to plastic deformation. It introduces the general properties of dislocations and treats the dislocation dynamics in some detail. Finally, examples are described of the processes in different classes of materials, i.e. semiconductors, ceramics, metals, intermetallic materials, and quasicrystals. The processes are illustrated by many electron micrographs of dislocations under stress and by video clips taken during in situ straining experiments in a high-voltage electron microscope showing moving dislocations. Thus, the users of the book also obtain an immediate impression and understanding of dislocation dynamics.

  17. Network dynamics and its relationships to topology and coupling structure in excitable complex networks

    International Nuclear Information System (INIS)

    Zhang Li-Sheng; Mi Yuan-Yuan; Gu Wei-Feng; Hu Gang

    2014-01-01

    All dynamic complex networks have two important aspects, pattern dynamics and network topology. Discovering different types of pattern dynamics and exploring how these dynamics depend on network topologies are tasks of both great theoretical importance and broad practical significance. In this paper we study the oscillatory behaviors of excitable complex networks (ECNs) and find some interesting dynamic behaviors of ECNs in oscillatory probability, the multiplicity of oscillatory attractors, period distribution, and different types of oscillatory patterns (e.g., periodic, quasiperiodic, and chaotic). In these aspects, we further explore strikingly sharp differences among network dynamics induced by different topologies (random or scale-free topologies) and different interaction structures (symmetric or asymmetric couplings). The mechanisms behind these differences are explained physically. (interdisciplinary physics and related areas of science and technology)

  18. Characterization of Enhancing MS Lesions by Dynamic Texture Parameter Analysis of Dynamic Susceptibility Perfusion Imaging

    Directory of Open Access Journals (Sweden)

    Rajeev K. Verma

    2016-01-01

    Full Text Available Purpose. The purpose of this study was to investigate statistical differences with MR perfusion imaging features that reflect the dynamics of Gadolinium-uptake in MS lesions using dynamic texture parameter analysis (DTPA. Methods. We investigated 51 MS lesions (25 enhancing, 26 nonenhancing lesions of 12 patients. Enhancing lesions (n=25 were prestratified into enhancing lesions with increased permeability (EL+; n=11 and enhancing lesions with subtle permeability (EL−; n=14. Histogram-based feature maps were computed from the raw DSC-image time series and the corresponding texture parameters were analyzed during the inflow, outflow, and reperfusion time intervals. Results. Significant differences (p<0.05 were found between EL+ and EL− and between EL+ and nonenhancing inactive lesions (NEL. Main effects between EL+ versus EL− and EL+ versus NEL were observed during reperfusion (mainly in mean and standard deviation (SD: EL+ versus EL− and EL+ versus NEL, while EL− and NEL differed only in their SD during outflow. Conclusion. DTPA allows grading enhancing MS lesions according to their perfusion characteristics. Texture parameters of EL− were similar to NEL, while EL+ differed significantly from EL− and NEL. Dynamic texture analysis may thus be further investigated as noninvasive endogenous marker of lesion formation and restoration.

  19. Opposite photo-induced deformations in azobenzene-containing polymers with different molecular architecture: Molecular dynamics study

    International Nuclear Information System (INIS)

    Ilnytskyi, Jaroslav M.; Neher, Dieter; Saphiannikova, Marina

    2011-01-01

    Photo-induced deformations in azobenzene-containing polymers (azo-polymers) are central to a number of applications, such as optical storage and fabrication of diffractive elements. The microscopic nature of the underlying opto-mechanical coupling is yet not clear. In this study, we address the experimental finding that the scenario of the effects depends on molecular architecture of the used azo-polymer. Typically, opposite deformations in respect to the direction of light polarization are observed for liquid crystalline and amorphous azo-polymers. In this study, we undertake molecular dynamics simulations of two different models that mimic these two types of azo-polymers. We employ hybrid force field modeling and consider only trans-isomers of azobenzene, represented as Gay-Berne sites. The effect of illumination on the orientation of the chromophores is considered on the level of orientational hole burning and emphasis is given to the resulting deformation of the polymer matrix. We reproduce deformations of opposite sign for the two models being considered here and discuss the relevant microscopic mechanisms in both cases.

  20. Dynamic Topography Revisited

    Science.gov (United States)

    Moresi, Louis

    2015-04-01

    Dynamic Topography Revisited Dynamic topography is usually considered to be one of the trinity of contributing causes to the Earth's non-hydrostatic topography along with the long-term elastic strength of the lithosphere and isostatic responses to density anomalies within the lithosphere. Dynamic topography, thought of this way, is what is left over when other sources of support have been eliminated. An alternate and explicit definition of dynamic topography is that deflection of the surface which is attributable to creeping viscous flow. The problem with the first definition of dynamic topography is 1) that the lithosphere is almost certainly a visco-elastic / brittle layer with no absolute boundary between flowing and static regions, and 2) the lithosphere is, a thermal / compositional boundary layer in which some buoyancy is attributable to immutable, intrinsic density variations and some is due to thermal anomalies which are coupled to the flow. In each case, it is difficult to draw a sharp line between each contribution to the overall topography. The second definition of dynamic topography does seem cleaner / more precise but it suffers from the problem that it is not measurable in practice. On the other hand, this approach has resulted in a rich literature concerning the analysis of large scale geoid and topography and the relation to buoyancy and mechanical properties of the Earth [e.g. refs 1,2,3] In convection models with viscous, elastic, brittle rheology and compositional buoyancy, however, it is possible to examine how the surface topography (and geoid) are supported and how different ways of interpreting the "observable" fields introduce different biases. This is what we will do. References (a.k.a. homework) [1] Hager, B. H., R. W. Clayton, M. A. Richards, R. P. Comer, and A. M. Dziewonski (1985), Lower mantle heterogeneity, dynamic topography and the geoid, Nature, 313(6003), 541-545, doi:10.1038/313541a0. [2] Parsons, B., and S. Daly (1983), The

  1. Study of the dynamics of an equation with two large different-order delays

    International Nuclear Information System (INIS)

    Kashchenko, I.S.

    2016-01-01

    The case where the larger delay is proportional to the square of the smaller delay is studied in detail. Regions of stability and instability of the equilibrium state and critical cases are found. In all critical cases, special evolutionary equations (quasinormal forms) are constructed. Their non-local dynamics determines the local behavior of solutions of the original equation [ru

  2. Algorithms and programs of dynamic mixture estimation unified approach to different types of components

    CERN Document Server

    Nagy, Ivan

    2017-01-01

    This book provides a general theoretical background for constructing the recursive Bayesian estimation algorithms for mixture models. It collects the recursive algorithms for estimating dynamic mixtures of various distributions and brings them in the unified form, providing a scheme for constructing the estimation algorithm for a mixture of components modeled by distributions with reproducible statistics. It offers the recursive estimation of dynamic mixtures, which are free of iterative processes and close to analytical solutions as much as possible. In addition, these methods can be used online and simultaneously perform learning, which improves their efficiency during estimation. The book includes detailed program codes for solving the presented theoretical tasks. Codes are implemented in the open source platform for engineering computations. The program codes given serve to illustrate the theory and demonstrate the work of the included algorithms.

  3. Dynamic rock tensile strengths of Laurentian granite: Experimental observation and micromechanical model

    Directory of Open Access Journals (Sweden)

    Kaiwen Xia

    2017-02-01

    Full Text Available Tensile strength is an important material property for rocks. In applications where rocks are subjected to dynamic loads, the dynamic tensile strength is the controlling parameter. Similar to the study of static tensile strength, there are various methods proposed to measure the dynamic tensile strength of rocks. Here we examine dynamic tensile strength values of Laurentian granite (LG measured from three methods: dynamic direct tension, dynamic Brazilian disc (BD test, and dynamic semi-circular bending (SCB. We found that the dynamic tensile strength from direct tension has the lowest value, and the dynamic SCB gives the highest strength at a given loading rate. Because the dynamic direct tension measures the intrinsic rock tensile strength, it is thus necessary to reconcile the differences in strength values between the direct tension and the other two methods. We attribute the difference between the dynamic BD results and the direct tension results to the overload and internal friction in BD tests. The difference between the dynamic SCB results and the direct tension results can be understood by invoking the non-local failure theory. It is shown that, after appropriate corrections, the dynamic tensile strengths from the two other tests can be reduced to those from direct tension.

  4. Genes contribute to the switching dynamics of bistable perception.

    Science.gov (United States)

    Shannon, Robert W; Patrick, Christopher J; Jiang, Yi; Bernat, Edward; He, Sheng

    2011-03-09

    Ordinarily, the visual system provides an unambiguous representation of the world. However, at times alternative plausible interpretations of a given stimulus arise, resulting in a dynamic perceptual alternation of the differing interpretations, commonly referred to as bistable or rivalrous perception. Recent research suggests that common neural mechanisms may be involved in the dynamics of very different types of bistable phenomena. Further, evidence has emerged that genetic factors may be involved in determining the rate of switch for at least one form of bistable perception, known as binocular rivalry. The current study evaluated whether genetic factors contribute to the switching dynamics for distinctly different variants of bistable perception in the same participant sample. Switching rates were recorded for MZ and DZ twin participants in two different bistable perception tasks, binocular rivalry and the Necker Cube. Strong concordance in switching rates across both tasks was evident for MZ but not DZ twins, indicating that genetic factors indeed contribute to the dynamics of multiple forms of bistable perception.

  5. Entanglement dynamics in itinerant fermionic and bosonic systems

    Science.gov (United States)

    Pillarishetty, Durganandini

    2017-04-01

    The concept of quantum entanglement of identical particles is fundamental in a wide variety of quantum information contexts involving composite quantum systems. However, the role played by particle indistinguishabilty in entanglement determination is being still debated. In this work, we study, theoretically, the entanglement dynamics in some itinerant bosonic and fermionic systems. We show that the dynamical behaviour of particle entanglement and spatial or mode entanglement are in general different. We also discuss the effect of fermionic and bosonic statistics on the dynamical behaviour. We suggest that the different dynamical behaviour can be used to distinguish between particle and mode entanglement in identical particle systems and discuss possible experimental realizations for such studies. I acknowledge financial support from DST, India through research Grant.

  6. Some aspects of animal behavior and community dynamics

    Directory of Open Access Journals (Sweden)

    Vikas Rai

    2011-09-01

    Full Text Available We simulate the dynamical behavior of a few two - dimensional predator - prey systems in two - dimensional parameter spaces to gain insight into how functional responses affect community dynamics. The insight gained helps us design three dimensional systems. We construct models for a few ecosystems with three species and study them using computer simulations. The models have been developed by linking food chains which have both kinds of predators: specialist as well as generalist. The linking functions are weakly non-linear. The three dimensional model ecosystems have sexually reproducing top - predators. We perform extensive simulations to figure out dynamics of dynamical possibilities caused by changes in animal behavior. The animals change the foraging strategies and behave differently in different environments. At the end of the paper, we examine how diseases can govern transitions in meandering of dynamical models in bounded volume of their phase spaces.

  7. Dynamic Programming: An Introduction by Example

    Science.gov (United States)

    Zietz, Joachim

    2007-01-01

    The author introduces some basic dynamic programming techniques, using examples, with the help of the computer algebra system "Maple". The emphasis is on building confidence and intuition for the solution of dynamic problems in economics. To integrate the material better, the same examples are used to introduce different techniques. One covers the…

  8. Analysing Stagecoach Network Problem Using Dynamic ...

    African Journals Online (AJOL)

    In this paper we present a recursive dynamic programming algorithm for solving the stagecoach problem. The algorithm is computationally more efficient than the first method as it obtains its minimum total cost using the suboptimal policies of the different stages without computing the cost of all the routes. By the dynamic ...

  9. A new approach combining different MRI methods to provide detailed view on swelling dynamics of xanthan tablets influencing drug release at different pH and ionic strength.

    Science.gov (United States)

    Mikac, Ursa; Sepe, Ana; Kristl, Julijana; Baumgartner, Sasa

    2010-08-03

    The key element in drug release from hydrophilic matrix tablets is the gel layer that regulates the penetration of water and controls drug dissolution and diffusion. We have selected magnetic resonance imaging (MRI) as the method of choice for visualizing the dynamic processes occurring during the swelling of xanthan tablets in a variety of media. The aims were (i) to develop a new method using MRI for accurate determination of penetration, swelling and erosion fronts, (ii) to investigate the effects of pH and ionic strength on swelling, and (iii) to study the influence of structural changes in xanthan gel on drug release. Two dimensional (2D) MRI and one dimensional single point imaging (SPI) of swollen xanthan tablets were recorded, together with T(2) mapping. The border between dry and hydrated glassy xanthan-the penetration front-was determined from 1D SPI signal intensity profiles. The erosion front was obtained from signal intensity profiles of 2D MR images. The swelling front, where xanthan is transformed from a glassy to a rubbery state (gel formation), was determined from T(2) profiles. Further, the new combination of MRI methods for swelling front determination enables to explain the appearance of the unusual "bright front" observed on 2D MR images in tablets swollen in HCl pH 1.2 media, which represents the position of swelling front. All six media studied, differing in pH and ionic strength, penetrate through the whole tablet in 4h+/-0.3h, but formation of the gel layer is significantly delayed. Unexpectedly, the position of the swelling front was the same, independently of the different xanthan gel structures formed under different conditions of pH and ionic strength. The position of the erosion front, on the other hand, is strongly dependent on pH and ionic strength, as reflected in different thicknesses of the gel layers. The latter are seen to be the consequence of the different hydrodynamic radii of the xanthan molecules, which affect the drug

  10. Dynamics of Liquids Confined in Porous Materials

    DEFF Research Database (Denmark)

    Berg, Marcella Cabrera

    mobility of the hydrogen atoms, mostly from water, present in conventional GIC. Water plays a big part in the setting process in GIC. It is the reaction medium in which the cations leach to crosslink. Furthermore, water also hydrates the siliceous hydrogel and the metal polyacrylate salts. In matured GIC...... dynamics in such complex hierarchical structure, where different motions occur in a broad range of time scales and simultaneously, can be difficult. So in this Ph.D. thesis, the experimental data was combined with preliminary classical molecular dynamics simulations (MD), aiming to investigate...... the different nanoscale water dynamics in the GIC. This unique approach opens new possibilities to better explore all the information contained in the neutron spectroscopy data. Selected materials were investigated by first understanding the molecular motions of the different aqueous polyacrylic acid solutions...

  11. Trajectories of mothers' emotional availability: relations with infant temperament in predicting attachment security.

    Science.gov (United States)

    Kim, Bo-Ram; Chow, Sy-Miin; Bray, Bethany; Teti, Douglas M

    2017-02-01

    The present study examined observations of parenting quality (mothers' emotional availability - EA) during infant bedtimes at 4 points across the infants' first year, assessing relations between levels and trajectories of EA and infant attachment at 12 months and the role of infant temperament in moderating these associations. The sample (N = 128) was predominantly Euro-American (82.5%) and at low socioeconomic risk. Latent growth curve modeling with latent basis coefficients indicated substantial individual differences in initial levels and slopes in EA trajectories across the first year. Both levels of maternal EA and EA trajectories across the first year predicted 12-month infant attachment security. Although maternal EA tended to decrease across the first year in the full sample, EA trajectories that showed a "bounce-back" between 6 and 12 months, suggesting more successful maternal adaptation to an expanding infant developmental repertoire, predicted greater infant security at 12 months. In addition, linkages between latent EA trajectories and 12-month attachment were moderated by 3-month infant temperamental reactivity and regulation. These findings indicate that infant attachment security is sensitive to both static and dynamic aspects of parenting quality across the first year, and that infant temperament can interact with both in predicting infant attachment.

  12. Dynamic analysis of a guided projectile during engraving process

    Directory of Open Access Journals (Sweden)

    Tao Xue

    2014-06-01

    Full Text Available The reliability of the electronic components inside a guided projectile is highly affected by the launch dynamics of guided projectile. The engraving process plays a crucial role on determining the ballistic performance and projectile stability. This paper analyzes the dynamic response of a guided projectile during the engraving process. By considering the projectile center of gravity moving during the engraving process, a dynamics model is established with the coupling of interior ballistic equations. The results detail the stress situation of a guided projectile band during its engraving process. Meanwhile, the axial dynamic response of projectile in the several milliseconds following the engraving process is also researched. To further explore how the different performance of the engraving band can affect the dynamics of guided projectile, this paper focuses on these two aspects: (a the effects caused by the different band geometry; and (b the effects caused by different band materials. The time domain and frequency domain responses show that the dynamics of the projectile are quite sensitive to the engraving band width. A material with a small modulus of elasticity is more stable than one with a high modulus of elasticity.

  13. Salience network dynamics underlying successful resistance of temptation

    Science.gov (United States)

    Nomi, Jason S; Calhoun, Vince D; Stelzel, Christine; Paschke, Lena M; Gaschler, Robert; Goschke, Thomas; Walter, Henrik; Uddin, Lucina Q

    2017-01-01

    Abstract Self-control and the ability to resist temptation are critical for successful completion of long-term goals. Contemporary models in cognitive neuroscience emphasize the primary role of prefrontal cognitive control networks in aligning behavior with such goals. Here, we use gaze pattern analysis and dynamic functional connectivity fMRI data to explore how individual differences in the ability to resist temptation are related to intrinsic brain dynamics of the cognitive control and salience networks. Behaviorally, individuals exhibit greater gaze distance from target location (e.g. higher distractibility) during presentation of tempting erotic images compared with neutral images. Individuals whose intrinsic dynamic functional connectivity patterns gravitate toward configurations in which salience detection systems are less strongly coupled with visual systems resist tempting distractors more effectively. The ability to resist tempting distractors was not significantly related to intrinsic dynamics of the cognitive control network. These results suggest that susceptibility to temptation is governed in part by individual differences in salience network dynamics and provide novel evidence for involvement of brain systems outside canonical cognitive control networks in contributing to individual differences in self-control. PMID:29048582

  14. Modeling initial contact dynamics during ambulation with dynamic simulation.

    Science.gov (United States)

    Meyer, Andrew R; Wang, Mei; Smith, Peter A; Harris, Gerald F

    2007-04-01

    Ankle-foot orthoses are frequently used interventions to correct pathological gait. Their effects on the kinematics and kinetics of the proximal joints are of great interest when prescribing ankle-foot orthoses to specific patient groups. Mathematical Dynamic Model (MADYMO) is developed to simulate motor vehicle crash situations and analyze tissue injuries of the occupants based multibody dynamic theories. Joint kinetics output from an inverse model were perturbed and input to the forward model to examine the effects of changes in the internal sagittal ankle moment on knee and hip kinematics following heel strike. Increasing the internal ankle moment (augmentation, equivalent to gastroc-soleus contraction) produced less pronounced changes in kinematic results at the hip, knee and ankle than decreasing the moment (attenuation, equivalent to gastroc-soleus relaxation). Altering the internal ankle moment produced two distinctly different kinematic curve morphologies at the hip. Decreased internal ankle moments increased hip flexion, peaking at roughly 8% of the gait cycle. Increasing internal ankle moments decreased hip flexion to a lesser degree, and approached normal at the same point in the gait cycle. Increasing the internal ankle moment produced relatively small, well-behaved extension-biased kinematic results at the knee. Decreasing the internal ankle moment produced more substantial changes in knee kinematics towards flexion that increased with perturbation magnitude. Curve morphologies were similar to those at the hip. Immediately following heel strike, kinematic results at the ankle showed movement in the direction of the internal moment perturbation. Increased internal moments resulted in kinematic patterns that rapidly approach normal after initial differences. When the internal ankle moment was decreased, differences from normal were much greater and did not rapidly decrease. This study shows that MADYMO can be successfully applied to accomplish forward

  15. Beam dynamics

    International Nuclear Information System (INIS)

    Abell, D; Adelmann, A; Amundson, J; Dragt, A; Mottershead, C; Neri, F; Pogorelov, I; Qiang, J; Ryne, R; Shalf, J; Siegerist, C; Spentzouris, P; Stern, E; Venturini, M; Walstrom, P

    2006-01-01

    We describe some of the accomplishments of the Beam Dynamics portion of the SciDAC Accelerator Science and Technology project. During the course of the project, our beam dynamics software has evolved from the era of different codes for each physical effect to the era of hybrid codes combining start-of-the-art implementations for multiple physical effects to the beginning of the era of true multi-physics frameworks. We describe some of the infrastructure that has been developed over the course of the project and advanced features of the most recent developments, the interplay betwen beam studies and simulations and applications to current machines at Fermilab. Finally we discuss current and future plans for simulations of the International Linear Collider

  16. Comparison of Static and Dynamic Balance at Different Levels of Sport Competition in Professional and Junior Elite Soccer Players.

    Science.gov (United States)

    Jadczak, Łukasz; Grygorowicz, Monika; Dzudziński, Witold; Śliwowski, Robert

    2018-04-12

    Jadczak, Ł, Grygorowicz, M, Dzudziński, W, and Śliwowski, R. Comparison of static and dynamic balance at different levels of sport competition in professional and junior elite soccer players. J Strength Cond Res XX(X): 000-000, 2018-The purpose of this study was to compare body balance control and balance recovery strategies of professional football players, representing various sports levels in static (eyes open, eyes closed) and dynamic conditions, both on the dominant and nondominant leg. Three groups of professional and junior elite soccer players were investigated: a PRO group (n = 52), a U-21 group (n = 55), and a U-19 group (n = 47). The study of body balance control was performed using a Delos Postural Proprioceptive System measurement tool. The analysis of the results showed an effect of group (p balance on both legs, which allows for a comprehensive comparison of body balance control and the balance recovery strategy depending on the represented sport level. Our study indicates that the higher the sport level of football players (the PRO group), the better their balance, which may indirectly contribute to the prevention of injuries and more effective performance of any actions directly related to the game.

  17. Corticomuscular synchronization with small and large dynamic force output

    Science.gov (United States)

    Andrykiewicz, Agnieszka; Patino, Luis; Naranjo, Jose Raul; Witte, Matthias; Hepp-Reymond, Marie-Claude; Kristeva, Rumyana

    2007-01-01

    Background Over the last few years much research has been devoted to investigating the synchronization between cortical motor and muscular activity as measured by EEG/MEG-EMG coherence. The main focus so far has been on corticomuscular coherence (CMC) during static force condition, for which coherence in beta-range has been described. In contrast, we showed in a recent study [1] that dynamic force condition is accompanied by gamma-range CMC. The modulation of the CMC by various dynamic force amplitudes, however, remained uninvestigated. The present study addresses this question. We examined eight healthy human subjects. EEG and surface EMG were recorded simultaneously. The visuomotor task consisted in isometric compensation for 3 forces (static, small and large dynamic) generated by a manipulandum. The CMC, the cortical EEG spectral power (SP), the EMG SP and the errors in motor performance (as the difference between target and exerted force) were analyzed. Results For the static force condition we found the well-documented, significant beta-range CMC (15–30 Hz) over the contralateral sensorimotor cortex. Gamma-band CMC (30–45 Hz) occurred in both small and large dynamic force conditions without any significant difference between both conditions. Although in some subjects beta-range CMC was observed during both dynamic force conditions no significant difference between conditions could be detected. With respect to the motor performance, the lowest errors were obtained in the static force condition and the highest ones in the dynamic condition with large amplitude. However, when we normalized the magnitude of the errors to the amplitude of the applied force (relative errors) no significant difference between both dynamic conditions was observed. Conclusion These findings confirm that during dynamic force output the corticomuscular network oscillates at gamma frequencies. Moreover, we show that amplitude modulation of dynamic force has no effect on the gamma CMC

  18. Corticomuscular synchronization with small and large dynamic force output

    Directory of Open Access Journals (Sweden)

    Witte Matthias

    2007-11-01

    Full Text Available Abstract Background Over the last few years much research has been devoted to investigating the synchronization between cortical motor and muscular activity as measured by EEG/MEG-EMG coherence. The main focus so far has been on corticomuscular coherence (CMC during static force condition, for which coherence in beta-range has been described. In contrast, we showed in a recent study 1 that dynamic force condition is accompanied by gamma-range CMC. The modulation of the CMC by various dynamic force amplitudes, however, remained uninvestigated. The present study addresses this question. We examined eight healthy human subjects. EEG and surface EMG were recorded simultaneously. The visuomotor task consisted in isometric compensation for 3 forces (static, small and large dynamic generated by a manipulandum. The CMC, the cortical EEG spectral power (SP, the EMG SP and the errors in motor performance (as the difference between target and exerted force were analyzed. Results For the static force condition we found the well-documented, significant beta-range CMC (15–30 Hz over the contralateral sensorimotor cortex. Gamma-band CMC (30–45 Hz occurred in both small and large dynamic force conditions without any significant difference between both conditions. Although in some subjects beta-range CMC was observed during both dynamic force conditions no significant difference between conditions could be detected. With respect to the motor performance, the lowest errors were obtained in the static force condition and the highest ones in the dynamic condition with large amplitude. However, when we normalized the magnitude of the errors to the amplitude of the applied force (relative errors no significant difference between both dynamic conditions was observed. Conclusion These findings confirm that during dynamic force output the corticomuscular network oscillates at gamma frequencies. Moreover, we show that amplitude modulation of dynamic force has no

  19. The Differences in Source Dynamics Between Intermediate-Depth and Deep EARTHQUAKES:A Comparative Study Between the 2014 Rat Islands Intermediate-Depth Earthquake and the 2015 Bonin Islands Deep Earthquake

    Science.gov (United States)

    Twardzik, C.; Ji, C.

    2015-12-01

    It has been proposed that the mechanisms for intermediate-depth and deep earthquakes might be different. While previous extensive seismological studies suggested that such potential differences do not significantly affect the scaling relationships of earthquake parameters, there has been only a few investigations regarding their dynamic characteristics, especially for fracture energy. In this work, the 2014 Mw7.9 Rat Islands intermediate-depth (105 km) earthquake and the 2015 Mw7.8 Bonin Islands deep (680 km) earthquake are studied from two different perspectives. First, their kinematic rupture models are constrained using teleseismic body waves. Our analysis reveals that the Rat Islands earthquake breaks the entire cold core of the subducting slab defined as the depth of the 650oC isotherm. The inverted stress drop is 4 MPa, compatible to that of intra-plate earthquakes at shallow depths. On the other hand, the kinematic rupture model of the Bonin Islands earthquake, which occurred in a region lacking of seismicity for the past forty years, according to the GCMT catalog, exhibits an energetic rupture within a 35 km by 30 km slip patch and a high stress drop of 24 MPa. It is of interest to note that although complex rupture patterns are allowed to match the observations, the inverted slip distributions of these two earthquakes are simple enough to be approximated as the summation of a few circular/elliptical slip patches. Thus, we investigate subsequently their dynamic rupture models. We use a simple modelling approach in which we assume that the dynamic rupture propagation obeys a slip-weakening friction law, and we describe the distribution of stress and friction on the fault as a set of elliptical patches. We will constrain the three dynamic parameters that are yield stress, background stress prior to the rupture and slip weakening distance, as well as the shape of the elliptical patches directly from teleseismic body waves observations. The study would help us

  20. Use of soil moisture dynamics and patterns at different spatio-temporal scales for the investigation of subsurface flow processes

    Directory of Open Access Journals (Sweden)

    T. Blume

    2009-07-01

    Full Text Available Spatial patterns as well as temporal dynamics of soil moisture have a major influence on runoff generation. The investigation of these dynamics and patterns can thus yield valuable information on hydrological processes, especially in data scarce or previously ungauged catchments. The combination of spatially scarce but temporally high resolution soil moisture profiles with episodic and thus temporally scarce moisture profiles at additional locations provides information on spatial as well as temporal patterns of soil moisture at the hillslope transect scale. This approach is better suited to difficult terrain (dense forest, steep slopes than geophysical techniques and at the same time less cost-intensive than a high resolution grid of continuously measuring sensors. Rainfall simulation experiments with dye tracers while continuously monitoring soil moisture response allows for visualization of flow processes in the unsaturated zone at these locations. Data was analyzed at different spacio-temporal scales using various graphical methods, such as space-time colour maps (for the event and plot scale and binary indicator maps (for the long-term and hillslope scale. Annual dynamics of soil moisture and decimeter-scale variability were also investigated. The proposed approach proved to be successful in the investigation of flow processes in the unsaturated zone and showed the importance of preferential flow in the Malalcahuello Catchment, a data-scarce catchment in the Andes of Southern Chile. Fast response times of stream flow indicate that preferential flow observed at the plot scale might also be of importance at the hillslope or catchment scale. Flow patterns were highly variable in space but persistent in time. The most likely explanation for preferential flow in this catchment is a combination of hydrophobicity, small scale heterogeneity in rainfall due to redistribution in the canopy and strong gradients in unsaturated conductivities leading to