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Sample records for normal developmental trajectories

  1. Developmental Trajectories of Early Communication Skills

    Science.gov (United States)

    Maatta, Sira; Laakso, Marja-Leena; Tolvanen, Asko; Ahonen, Timo; Aro, Tuija

    2012-01-01

    Purpose: This study focused on developmental trajectories of prelinguistic communication skills and their connections to later parent-reported language difficulties. Method: The participants represent a subset of a community-based sample of 508 children. Data include parent reports of prelinguistic communication skills at 12, 15, 18, and 21 months…

  2. Developmental Trajectories of Childhood Obesity and Risk Behaviors in Adolescence

    Science.gov (United States)

    Huang, David Y. C.; Lanza, H. Isabella; Wright-Volel, Kynna; Anglin, M. Douglas

    2013-01-01

    Using group-based trajectory modeling, this study examined 5156 adolescents from the child sample of the 1979 National Longitudinal Survey of Youth to identify developmental trajectories of obesity from ages 6-18 and evaluate associations of such trajectories with risk behaviors and psychosocial health in adolescence. Four distinctive obesity…

  3. Developmental Trajectories of Girls' and Boys' Delinquency and Associated Problems

    Science.gov (United States)

    Pepler, Debra J.; Jiang, Depeng; Craig, Wendy M.; Connolly, Jennifer

    2010-01-01

    Developmental trajectories in delinquency through adolescence were studied along with family and peer relationship problems. Drawing from eight waves of data over seven years, we conducted trajectory analyses with a sample of 746 students (402 girls; 344 boys). Analyzing girls and boys together, a five-class model emerged: 60% of the adolescents…

  4. Tracing developmental trajectories of oppositional defiant behaviors in preschool children.

    Directory of Open Access Journals (Sweden)

    Lourdes Ezpeleta

    Full Text Available Previous studies on developmental trajectories have used ad hoc definitions of oppositional defiant behaviors (ODB, which makes it difficult to compare results. This article defines developmental trajectories of ODB from ages 3-5 based on five different standard measurements derived from three separate instruments.A sample of 622 three-year-old preschoolers, followed up at ages 4, 5, and 6, was assessed with the five measures of oppositionality answered by parents and teachers. Growth-Mixture-Modeling (GMM estimated separate developmental trajectories for each ODB measure for ages 3 to 5.The number of classes-trajectories obtained in each GMM depended on the ODB measure, but two clear patterns emerged: four trajectories (persistent low, decreasers, increasers/high increasers, persistent moderate/persistent high or three trajectories (persistent low, decreasers, increasers/high increasers. Persistent high trajectories accounted for 4.4%-9.5% of the children. The trajectories emerging from the different ODB measures at ages 3 to 5 discriminated disruptive disorders, comorbidity, use of services, and impairment at age 6, and globally showed a similar pattern, summarizing longitudinal information on oppositionality in preschool children in a similar way.Trajectories resulting from standard scales of the questionnaires have predictive validity for identifying relevant clinical outcomes, but are measure-specific. The results contribute to knowledge about the development of ODB in preschool children.

  5. Developmental Trajectories of Young Girls with Fragile X Syndrome

    Science.gov (United States)

    Hatton, Deborah D.; Wheeler, Anne; Sideris, John; Sullivan, Kelly; Reichardt, Alison; Roberts, Jane; Clark, Renee; Bailey, Donald B., Jr.

    2009-01-01

    To describe the early phenotype of girls with full mutation fragile X, we used 54 observations of 15 girls between the ages of 6 months and 9 years to examine developmental trajectories as measured by the Battelle Development Inventory. In this sample, autistic behavior was associated with poorer developmental outcomes, primarily due to…

  6. Developmental trajectories of bullying and associated factors.

    Science.gov (United States)

    Pepler, Debra; Jiang, Depeng; Craig, Wendy; Connolly, Jennifer

    2008-01-01

    Trajectories in bullying through adolescence were studied along with individual, family, and peer relationship factors. At the outset, participants' ages ranged from 10 to 14; 74% identified as European Canadian with the remainder from diverse backgrounds. With 8 waves of data over 7 years, 871 students (466 girls and 405 boys) were studied to reveal 4 trajectories: 9.9% reported consistently high levels of bullying, 13.4% reported early moderate levels desisting to almost no bullying at the end of high school, 35.1% reported consistently moderate levels, and 41.6% almost never reported bullying. Students who bullied had elevated risks in individual, parent, and peer relationship domains. Risk profiles and trajectories provide direction for interventions to curtail the development of power and aggression in relationships.

  7. Developmental Trajectories of Form Perception: A Story of Attention

    Science.gov (United States)

    Kovshoff, Hanna; Iarocci, Grace; Shore, David I.; Burack, Jacob A.

    2015-01-01

    The developmental trajectories of selective and divided attention were examined in relation to the processing of hierarchically integrated stimuli. The participants included children in 4 age groups (6, 8, 10, and 12 years) and a group of young adults (24 years) who completed 2 computer-based attention tasks. In the selective attention task, the…

  8. Developmental trajectories in food allergy: a review.

    LENUS (Irish Health Repository)

    DunnGalvin, A

    2009-01-01

    Increasing recognition of the importance of the relationships between perceptions, emotions, behaviors and health has changed the way health and disease are portrayed and researched. A chronic condition may affect and\\/or interact with already existing normative demands and changes in socialization. Although the prevalence of food allergy and anaphylaxis have been reportedly increasing, the emotional and social impact of growing up with food allergy has received little emphasis. In this paper, we present current findings on the biopsychosocial impact of food allergy on children in order to gain insight into the food allergy experience, from the perspective of the child, teen, and parent living with food allergy, with particular attention to developmental aspects. Due to the scarcity of publications on the psychosocial dimensions of food allergy, we also draw on selected literature on children\\'s and parent\\'s experience of, and coping with chronic disease that may inform research into food allergy. To this end, we review some general developmental mechanisms that may underpin and explain normative age-graded shifts in patterns of coping across childhood and adolescence. We also highlight gaps in the literature and assess implications of current research in food allergy and other chronic diseases for intervention and prevention of negative short and long term outcomes.

  9. Developmental trajectory of time perspective: From children to older adults.

    Science.gov (United States)

    Chen, Tao; Liu, Lu-Lu; Cui, Ji-Fang; Chen, Xing-Jie; Wang, Ya

    2016-12-01

    Time perspective is a fundamental dimension of the psychological time construct, with a pervasive and powerful influence on human behavior. However, the developmental trajectory of time perspective across a human lifespan remains unclear. The current study aimed to portray the developmental trajectory of all dimensions of time perspectives from children to older adults in a large sample. A total of 1,901 individuals (aged 9-84 years) completed measures of time perspective. They were then divided into five age groups: children, teenagers, young adults, middle-aged adults, and older adults. Results suggested that each time perspective showed a unique developmental pattern across the lifespan. Moreover, perceived economic situation and education were related to some dimensions of time perspective. © 2016 The Institute of Psychology, Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.

  10. Developmental Trajectories of Male Physical Violence and Theft

    Science.gov (United States)

    Barker, Edward D.; Séguin, Jean R.; White, Helene Raskin; Bates, Marsha E.; Lacourse, Éric; Carbonneau, René; Tremblay, Richard E.

    2012-01-01

    Context Neurocognitive mechanisms have long been hypothesized to influence developmental trajectories of antisocial behavior. However, studies examining this association tend to aggregate a variety of problem behaviors that may be differently affected by neurocognitive deficits. Objective To describe the developmental trajectories of physical violence and theft from adolescence to adulthood, their associations, and the neurocognitive characteristics of individuals following different patterns of trajectory association. Design Accelerated cohort-sequential, longitudinal design. Setting Rutgers Health and Human Development Project. Participants Six hundred ninety-eight men. Main Outcome Measures Self-reports of physical violence (ages 12–24 years) and theft (ages 12–31 years) were collected across 5 waves. Neurocognitive performance was assessed with executive function and verbal IQ tests between late adolescence and early adulthood. Results The majority (55%) of subjects showed an increased frequency of theft during the study period, while only a minority (13%) evinced an increasing frequency of physical violence. Executive function and verbal IQ performance were negatively related to high frequency of physical violence but positively related to high frequency of theft. Conclusions Developmental trajectories of physical violence and theft during adolescence and early adulthood are different and differently related to neurocognitive functioning. Global indexes of antisocial behavior mask the development of antisocial behavior subtypes and putative causal mechanisms. PMID:17485611

  11. Trajectories of cortical surface area and cortical volume maturation in normal brain development

    Directory of Open Access Journals (Sweden)

    Simon Ducharme

    2015-12-01

    Full Text Available This is a report of developmental trajectories of cortical surface area and cortical volume in the NIH MRI Study of Normal Brain Development. The quality-controlled sample included 384 individual typically-developing subjects with repeated scanning (1–3 per subject, total scans n=753 from 4.9 to 22.3 years of age. The best-fit model (cubic, quadratic, or first-order linear was identified at each vertex using mixed-effects models, with statistical correction for multiple comparisons using random field theory. Analyses were performed with and without controlling for total brain volume. These data are provided for reference and comparison with other databases. Further discussion and interpretation on cortical developmental trajectories can be found in the associated Ducharme et al.׳s article “Trajectories of cortical thickness maturation in normal brain development – the importance of quality control procedures” (Ducharme et al., 2015 [1].

  12. Normal composite face effects in developmental prosopagnosia.

    Science.gov (United States)

    Biotti, Federica; Wu, Esther; Yang, Hua; Jiahui, Guo; Duchaine, Bradley; Cook, Richard

    2017-10-01

    Upright face perception is thought to involve holistic processing, whereby local features are integrated into a unified whole. Consistent with this view, the top half of one face appears to fuse perceptually with the bottom half of another, when aligned spatially and presented upright. This 'composite face effect' reveals a tendency to integrate information from disparate regions when faces are presented canonically. In recent years, the relationship between susceptibility to the composite effect and face recognition ability has received extensive attention both in participants with normal face recognition and participants with developmental prosopagnosia. Previous results suggest that individuals with developmental prosopagnosia may show reduced susceptibility to the effect suggestive of diminished holistic face processing. Here we describe two studies that examine whether developmental prosopagnosia is associated with reduced composite face effects. Despite using independent samples of developmental prosopagnosics and different composite procedures, we find no evidence for reduced composite face effects. The experiments yielded similar results; highly significant composite effects in both prosopagnosic groups that were similar in magnitude to the effects found in participants with normal face processing. The composite face effects exhibited by both samples and the controls were greatly diminished when stimulus arrangements were inverted. Our finding that the whole-face binding process indexed by the composite effect is intact in developmental prosopagnosia indicates that other factors are responsible for developmental prosopagnosia. These results are also inconsistent with suggestions that susceptibility to the composite face effect and face recognition ability are tightly linked. While the holistic process revealed by the composite face effect may be necessary for typical face perception, it is not sufficient; individual differences in face recognition ability

  13. Developmental trajectories in primary schoolchildren using n-back task

    Directory of Open Access Journals (Sweden)

    Mónica eLópez-Vicente

    2016-05-01

    Full Text Available Background: Neuropsychological instruments to assess cognitive trajectories during childhood in epidemiological studies are needed. This would improve neurodevelopment characterization in order to identify its potential determinants. We aimed to study whether repeated measures of n-back, a working memory task, detect developmental trajectories in schoolchildren during a one-year follow-up.Methods: We administered the n-back task to 2,897 healthy children aged 7-11 years old from 39 schools in Barcelona (Spain. The task consisted of 2 levels of complexity or loads (2- and 3-back and 2 different stimuli (numbers and words. Participants performed the task four times from January 2012 to March 2013. To study the trajectories during the follow-up, we performed linear mixed-effects models including school, individual and age as random effects.Results: We observed improvements related to age in n-back outcomes d’, HRT and accuracy, as well as reduced cognitive growth at older ages in d’ and HRT. Greater improvements in performance were observed at younger ages, in 2-back, in verbal rather than numerical stimuli and in girls compared to boys. Boys responded faster at baseline, while girls showed increased growth in 2-back numbers. Children with ADHD (Attention Deficit and Hyperactivity Disorder symptoms (15% of boys and 6% of girls had a lower working memory at baseline, but they showed similar cognitive growth trajectories in numbers variants of the task, as compared to children without ADHD symptoms. However, the age-related improvement in response speed was not observed in children with ADHD symptoms. Conclusions: Changes in n-back outcomes reflected developmental trajectories in one-year follow-up. The present results suggest that the repeated administration of this task can be used to study the factors that may alter the cognitive development during childhood.

  14. Developmental trajectories of adolescent popularity: a growth curve modelling analysis.

    Science.gov (United States)

    Cillessen, Antonius H N; Borch, Casey

    2006-12-01

    Growth curve modelling was used to examine developmental trajectories of sociometric and perceived popularity across eight years in adolescence, and the effects of gender, overt aggression, and relational aggression on these trajectories. Participants were 303 initially popular students (167 girls, 136 boys) for whom sociometric data were available in Grades 5-12. The popularity and aggression constructs were stable but non-overlapping developmental dimensions. Growth curve models were run with SAS MIXED in the framework of the multilevel model for change [Singer, J. D., & Willett, J. B. (2003). Applied longitudinal data analysis. Oxford, UK: Oxford University Press]. Sociometric popularity showed a linear change trajectory; perceived popularity showed nonlinear change. Overt aggression predicted low sociometric popularity but an increase in perceived popularity in the second half of the study. Relational aggression predicted a decrease in sociometric popularity, especially for girls, and continued high-perceived popularity for both genders. The effect of relational aggression on perceived popularity was the strongest around the transition from middle to high school. The importance of growth curve models for understanding adolescent social development was discussed, as well as specific issues and challenges of growth curve analyses with sociometric data.

  15. Early Risk Factors of Overweight Developmental Trajectories during Middle Childhood.

    Directory of Open Access Journals (Sweden)

    Laura E Pryor

    Full Text Available Research is needed to identify early life risk factors associated with different developmental paths leading to overweight by adolescence.To model heterogeneity in overweight development during middle childhood and identify factors associated with differing overweight trajectories.Data was drawn from the Quebec Longitudinal Study of Child Development (QLSCD; 1998-2010. Trained research assistants measured height and weight according to a standardized protocol and conducted yearly home interviews with the child's caregiver (mother in 98% of cases. Information on several putative early life risk factors for the development of overweight were obtained, including factors related to the child's perinatal, early behavioral family and social environment. Group-based trajectories of the probability of overweight (6-12 years were identified with a semiparametric method (n=1678. Logistic regression analyses were used to identify early risk factors (5 months- 5 years associated with each trajectory.Three trajectories of overweight were identified: "early-onset overweight" (11.0 %, "late-onset overweight" (16.6% and "never overweight" (72.5%. Multinomial analyses indicated that children in the early and late-onset group, compared to the never overweight group, had 3 common types of risk factors: parental overweight, preschool overweight history, and large size for gestational age. Maternal overprotection (OR= 1.12, CI: 1.01-1.25, short nighttime sleep duration (OR=1.66, CI: 1.07-2.57, and immigrant status (OR=2.01, CI: 1.05-3.84 were factors specific to the early-onset group. Finally, family food insufficiency (OR=1.81, CI: 1.00-3.28 was weakly associated with membership in the late-onset trajectory group.The development of overweight in childhood follows two different trajectories, which have common and distinct risk factors that could be the target of early preventive interventions.

  16. Early Risk Factors of Overweight Developmental Trajectories during Middle Childhood

    Science.gov (United States)

    Pryor, Laura E.; Brendgen, Mara; Tremblay, Richard E.; Pingault, Jean-Baptiste; Liu, Xuecheng; Dubois, Lise; Touchette, Evelyne; Falissard, Bruno; Boivin, Michel; Côté, Sylvana M.

    2015-01-01

    Background Research is needed to identify early life risk factors associated with different developmental paths leading to overweight by adolescence. Objectives To model heterogeneity in overweight development during middle childhood and identify factors associated with differing overweight trajectories. Methods Data was drawn from the Quebec Longitudinal Study of Child Development (QLSCD; 1998-2010). Trained research assistants measured height and weight according to a standardized protocol and conducted yearly home interviews with the child’s caregiver (mother in 98% of cases). Information on several putative early life risk factors for the development of overweight were obtained, including factors related to the child’s perinatal, early behavioral family and social environment. Group-based trajectories of the probability of overweight (6-12 years) were identified with a semiparametric method (n=1678). Logistic regression analyses were used to identify early risk factors (5 months- 5 years) associated with each trajectory. Results Three trajectories of overweight were identified: “early-onset overweight” (11.0 %), “late-onset overweight” (16.6%) and “never overweight” (72.5%). Multinomial analyses indicated that children in the early and late-onset group, compared to the never overweight group, had 3 common types of risk factors: parental overweight, preschool overweight history, and large size for gestational age. Maternal overprotection (OR= 1.12, CI: 1.01-1.25), short nighttime sleep duration (OR=1.66, CI: 1.07-2.57), and immigrant status (OR=2.01, CI: 1.05-3.84) were factors specific to the early-onset group. Finally, family food insufficiency (OR=1.81, CI: 1.00-3.28) was weakly associated with membership in the late-onset trajectory group. Conclusions The development of overweight in childhood follows two different trajectories, which have common and distinct risk factors that could be the target of early preventive interventions. PMID

  17. Interpersonal Problems and Developmental Trajectories of Binge Eating Disorder

    Science.gov (United States)

    Blomquist, Kerstin K.; Ansell, Emily B.; White, Marney A.; Masheb, Robin M.; Grilo, Carlos M.

    2012-01-01

    Objective To explore associations between specific interpersonal constructs and the developmental progression of behaviors leading to binge eating disorder (BED). Method Eighty-four consecutively evaluated, treatment-seeking obese (BMI ≥ 30) men and women with BED were assessed with structured diagnostic and clinical interviews and completed a battery of established measures to assess the current and developmental eating- and weight-related variables as well as interpersonal functioning. Results Using the interpersonal circumplex structural summary method, amplitude, elevation, the affiliation dimension, and the quadratic coefficient for the dominance dimension were associated with eating and weight-related developmental variables. The amplitude coefficient and more extreme interpersonal problems on the dominance dimension (quadratic)—i.e., problems with being extremely high (domineering) or low in dominance (submissive)—were significantly associated with ayounger age at onset of binge eating, BED, and overweight as well as accounted for significant variance in age at binge eating, BED, and overweight onset. Greater interpersonal problems with having an overly affiliative interpersonal style were significantly associated with, and accounted for significant variance in, ayounger age at diet onset. Discussion Findings provide further support for the importance of interpersonal problems among adults with BED and converge with recent work highlighting the importance of specific types of interpersonal problems for understanding heterogeneity and different developmental trajectories of individuals with BED. PMID:22727087

  18. Sex differences in normal age trajectories of functional brain networks.

    Science.gov (United States)

    Scheinost, Dustin; Finn, Emily S; Tokoglu, Fuyuze; Shen, Xilin; Papademetris, Xenophon; Hampson, Michelle; Constable, R Todd

    2015-04-01

    Resting-state functional magnetic resonance image (rs-fMRI) is increasingly used to study functional brain networks. Nevertheless, variability in these networks due to factors such as sex and aging is not fully understood. This study explored sex differences in normal age trajectories of resting-state networks (RSNs) using a novel voxel-wise measure of functional connectivity, the intrinsic connectivity distribution (ICD). Males and females showed differential patterns of changing connectivity in large-scale RSNs during normal aging from early adulthood to late middle-age. In some networks, such as the default-mode network, males and females both showed decreases in connectivity with age, albeit at different rates. In other networks, such as the fronto-parietal network, males and females showed divergent connectivity trajectories with age. Main effects of sex and age were found in many of the same regions showing sex-related differences in aging. Finally, these sex differences in aging trajectories were robust to choice of preprocessing strategy, such as global signal regression. Our findings resolve some discrepancies in the literature, especially with respect to the trajectory of connectivity in the default mode, which can be explained by our observed interactions between sex and aging. Overall, results indicate that RSNs show different aging trajectories for males and females. Characterizing effects of sex and age on RSNs are critical first steps in understanding the functional organization of the human brain. © 2014 Wiley Periodicals, Inc.

  19. Developmental trajectories of irritability and bidirectional associations with maternal depression.

    Science.gov (United States)

    Wiggins, Jillian Lee; Mitchell, Colter; Stringaris, Argyris; Leibenluft, Ellen

    2014-11-01

    Irritability is a dimensional trait in typical development and a common presenting symptom in many psychiatric disorders, including depression. However, little is known about the developmental trajectory of irritability or how child irritability interacts with maternal depression. The present study identifies classes of irritability trajectories from toddlerhood to middle childhood; characterizes maternal depression and other family, social environment, and child variables within each irritability trajectory class; and, as a more exploratory analysis, examines bidirectional associations between maternal depression and child irritability. A total of 4,898 families from the Fragile Families and Child Wellbeing Study reported on irritability symptoms at ages 3, 5, and 9 years, assessed with items from the Child Behavior Checklist. Parental major depressive episode was assessed using the Composite International Diagnostic Interview-Short Form at child ages 1, 3, 5, and 9 years. A latent class growth analysis identified 5 irritability classes: low decreasing; moderate decreasing; high steady; initially very high, then decreasing; and high increasing. Children with more severe irritability trajectories are more likely to have mothers with recurrent depression, and, with the exception of the most severe (high increasing irritability) class, were more likely to have mothers who were exposed to violence. Moreover, paternal depression and alcohol abuse, as well as maternal drug and alcohol abuse, were also risk factors for membership in the more severe irritability classes. A latent auto-regressive cross-lag model showed that child irritability at ages 3 and 5 years is associated with increased mother depression at ages 5 and 9, respectively. Conversely, mother depression at child ages 1 and 3 years is associated with increased child irritability at 3 and 5. Irritability development across toddlerhood and middle childhood has 5 main trajectory types, which differ on maternal

  20. Developmental Trajectories for Children With Dyslexia and Low IQ Poor Readers

    Science.gov (United States)

    2016-01-01

    Reading difficulties are found in children with both high and low IQ and it is now clear that both groups exhibit difficulties in phonological processing. Here, we apply the developmental trajectories approach, a new methodology developed for studying language and cognitive impairments in developmental disorders, to both poor reader groups. The trajectory methodology enables identification of atypical versus delayed development in datasets gathered using group matching designs. Regarding the cognitive predictors of reading, which here are phonological awareness, phonological short-term memory (PSTM) and rapid automatized naming (RAN), the method showed that trajectories for the two groups diverged markedly. Children with dyslexia showed atypical development in phonological awareness, while low IQ poor readers showed developmental delay. Low IQ poor readers showed atypical PSTM and RAN development, but children with dyslexia showed developmental delay. These divergent trajectories may have important ramifications for supporting each type of poor reader, although all poor readers showed weakness in all areas. Regarding auditory processing, the developmental trajectories were very similar for the two poor reader groups. However, children with dyslexia demonstrated developmental delay for auditory discrimination of Duration, while the low IQ children showed atypical development on this measure. The data show that, regardless of IQ, poor readers have developmental trajectories that differ from typically developing children. The trajectories approach enables differences in trajectory classification to be identified across poor reader group, as well as specifying the individual nature of these trajectories. PMID:27110928

  1. Gender-Specific Developmental Trajectories of Anxiety during Adolescence : Determinants and Outcomes. The TRAILS Study

    NARCIS (Netherlands)

    Legerstee, Jeroen S; Verhulst, Frank C; Robbers, Sylvana C C; Ormel, Johan; Oldehinkel, Albertine J; van Oort, Floor V A

    OBJECTIVE: To identify developmental trajectories of anxiety symptoms for adolescent girls and boys. Trajectories were compared with regard to early-adolescent risk factors and psychiatric outcomes during adolescence and in young adulthood. METHOD: A community sample of 2,230 adolescents was

  2. Normal female puberty in a developmental perspective

    DEFF Research Database (Denmark)

    Bourguignon, Jean-Pierre; Juul, Anders

    2012-01-01

    Puberty is unique in the sense that its onset shows an extraordinary individual variability of about 5 years, the basis of which being still elusive despite research efforts to understand the reason why. Continuing changes in environmental influences and interaction with genetic determinants...... with less obvious changes in menarcheal age. Conceptually, puberty and subsequent reproduction appear now to be influenced by conditions not only at the time when they occur, but also during fetal and perinatal life. In addition, these influences can be apparently opposing since early maturation follows...... fetal malnourishment and postnatal overfeeding. In this review, the semiology and pathophysiology of puberty are discussed in a lifelong developmental perspective....

  3. Developmental Trajectories for Children with Dyslexia and Low IQ Poor Readers

    Science.gov (United States)

    Kuppen, Sarah E. A.; Goswami, Usha

    2016-01-01

    Reading difficulties are found in children with both high and low IQ and it is now clear that both groups exhibit difficulties in phonological processing. Here, we apply the developmental trajectories approach, a new methodology developed for studying language and cognitive impairments in developmental disorders, to both poor reader groups. The…

  4. Developmental Trajectories of Structural and Pragmatic Language Skills in School-Aged Children with Williams Syndrome

    Science.gov (United States)

    Van Den Heuvel, E.; Manders, E.; Swillen, A.; Zink, I.

    2016-01-01

    Background: This study aimed to compare developmental courses of structural and pragmatic language skills in school-aged children with Williams syndrome (WS) and children with idiopathic intellectual disability (IID). Comparison of these language trajectories could highlight syndrome-specific developmental features. Method: Twelve monolingual…

  5. Job satisfaction developmental trajectories and health: A life course perspective.

    Science.gov (United States)

    Dirlam, Jonathan; Zheng, Hui

    2017-04-01

    Understanding the health consequence of job dissatisfaction becomes increasingly important because job insecurity, stress and dissatisfaction have significantly increased in the United States in the last decade. Despite the extensive work in this area, prior studies nonetheless may underestimate the harmful effect of job dissatisfaction due to the cross-sectional nature of their data and sample selection bias. This study applies a life-course approach to more comprehensively examine the relationship between job satisfaction and health. Using data from the NLSY 1979 cohort, we estimate group based job satisfaction trajectories of respondents starting at age 25 and ending at age 39. Four job satisfaction trajectory groups are identified, a consistently high satisfaction group, a downward group, an upward group, and a lowest satisfaction group. We examine the effects of these trajectories on several physical and mental health outcomes of respondents in their early forties. We find membership in the lowest job satisfaction trajectory group to be negatively associated with all five mental health outcomes, supporting the accumulation of risks life course model. Those in the upward job satisfaction trajectory group have similar health outcomes to those in the high job satisfaction trajectory group, supporting the social mobility life course model. Overall, we find the relationship between job satisfaction trajectories and health to be stronger for mental health compared to physical health. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Developmental Links between Trajectories of Physical Violence, Vandalism, Theft, and Alcohol-Drug Use from Childhood to Adolescence

    Science.gov (United States)

    van Lier, Pol A. C.; Vitaro, Frank; Barker, Edward D.; Koot, Hans M.; Tremblay, Richard E.

    2009-01-01

    Differences in developmental trajectories of physical violence, vandalism, theft, and alcohol-drug use from ages 10 to 15 were studied. For females and for males, three trajectories of theft and of alcohol-drug use increased from 10 years to 15 years, while only the high trajectory of vandalism increased from ten to 14. All trajectories of…

  7. Developmental trajectories of work-family conflict for Finnish workers in midlife.

    Science.gov (United States)

    Rantanen, Johanna; Kinnunen, Ulla; Pulkkinen, Lea; Kokko, Katja

    2012-07-01

    This study investigated the developmental trajectories of work-family conflict among the same participants (n = 277; 48% female) at ages 36, 42, and 50. Across this 14-year time span, with respect to the sample as a whole, there was no significant change in the mean levels of work-to-family conflict (WFC) or family to-work conflict (FWC). However, latent profile analyses revealed four latent trajectories within the sample, showing both mean-level stability and change in WFC and FWC: (1) "WFC decreasing" (n = 151); (2) "WFC and FWC stable low" (n = 105); (3) "WFC and FWC increasing" (n = 14); and (4) "FWC decreasing" (n = 7). Of these trajectories the strongest contrast existed between the WFC and FWC stable low and the WFC and FWC increasing trajectories: the former had the lowest and the latter the highest number of weekly working hours at ages 36, 42, and 50, and in the former but not in the latter the number of children living at home significantly decreased from age 36 to 50. Also, at ages 42 and 50 the WFC and FWC increasing trajectory showed higher job exhaustion and depressive symptoms than the WFC and FWC stable low trajectory. Altogether these findings suggest that work-family conflict is not limited to the early part of employees' working career and that developmental trajectories of work-family conflict exhibit a substantial amount of heterogeneity.

  8. Contrasting developmental trajectories in the earliest known tetrapod forelimbs.

    Science.gov (United States)

    Callier, Viviane; Clack, Jennifer A; Ahlberg, Per E

    2009-04-17

    Ichthyostega and Acanthostega are the earliest tetrapods known from multiple near-complete skeletons, with Acanthostega generally considered the more primitive. New material indicates differing ontogenetic trajectories for their forelimbs: In Ichthyostega, the pattern of muscle attachment processes on small humeri (upper arm bones) resembles that in "fish" members of the tetrapod stem group such as Tiktaalik, whereas large humeri approach (but fail to attain) the tetrapod crown-group condition; in Acanthostega, both small and large humeri exhibit the crown-group pattern. We infer that Ichthyostega underwent greater locomotory terrestrialization during ontogeny. The newly recognized primitive characteristics also suggest that Ichthyostega could be phylogenetically more basal than Acanthostega.

  9. Children with Differing Developmental Trajectories of Prelinguistic Communication Skills: Language and Working Memory at Age 5

    Science.gov (United States)

    Määttä, Sira; Laakso, Marja-Leena; Tolvanen, Asko; Ahonen, Timo; Aro, Tuija

    2014-01-01

    Purpose: In this article, the authors examine the developmental continuity from prelinguistic communication to kindergarten age in language and working memory capacity. Method: Following work outlining 6 groups of children with different trajectories of early communication development (ECD; Määttä, Laakso, Tolvanen, Ahonen, & Aro, 2012), the…

  10. Research Review: A Critical Review of Studies on the Developmental Trajectories of Antisocial Behavior in Females

    Science.gov (United States)

    Fontaine, Nathalie; Carbonneau, Rene; Vitaro, Frank; Barker, Edward D.; Tremblay, Richard E.

    2009-01-01

    Background: Knowledge on the onset and the development of antisocial behavior in females is limited, because most of the research in this domain is based on males. Methods: We critically reviewed 46 empirical studies that examined developmental trajectories of antisocial behavior in females, notably to help determine whether or not an…

  11. Mapping Developmental Precursors of Cyber-Aggression: Trajectories of Risk Predict Perpetration and Victimization

    Science.gov (United States)

    Modecki, Kathryn L.; Barber, Bonnie L.; Vernon, Lynnette

    2013-01-01

    Technologically mediated contexts are social arenas in which adolescents can be both perpetrators and victims of aggression. Yet, there remains little understanding of the developmental etiology of cyber aggression, itself, as experienced by either perpetrators or victims. The current study examines 3-year latent within-person trajectories of…

  12. Similar Developmental Trajectories in Autism and Asperger Syndrome: From Early Childhood to Adolescence

    Science.gov (United States)

    Szatmari, Peter; Bryson, Susan; Duku, Eric; Vaccarella, Liezanne; Zwaigenbaum, Lonnie; Bennett, Teresa; Boyle, Michael H.

    2009-01-01

    Objective: The objective of this study was to chart the developmental trajectories of high-functioning children with autism spectrum disorders (ASD) from early childhood to adolescence using the presence and absence of structural language impairment (StrLI) as a way of differentiating autism from Asperger syndrome (AS). Method: Sixty-four…

  13. Developmental Trajectories of Work Values and Job Entitlement Beliefs in the Transition to Adulthood

    Science.gov (United States)

    Chow, Angela; Krahn, Harvey J.; Galambos, Nancy L.

    2014-01-01

    Employing a life span developmental systems perspective, this study used a 5-wave (1985-1992) Canadian longitudinal data set (N = 404) to examine trajectories of intrinsic and extrinsic work values and job entitlement beliefs from age 18 to 25. Piecewise growth models (Slope 1: age 18-20; Slope 2: age 20-25) showed intriguing patterns of change.…

  14. Deep Processing Strategies and Critical Thinking: Developmental Trajectories Using Latent Growth Analyses

    Science.gov (United States)

    Phan, Huy P.

    2011-01-01

    The author explored the developmental courses of deep learning approach and critical thinking over a 2-year period. Latent growth curve modeling (LGM) procedures were used to test and trace the trajectories of both theoretical frameworks over time. Participants were 264 (119 women, 145 men) university undergraduates. The Deep Learning subscale of…

  15. Developmental trajectories of cerebrovascular reactivity in healthy children and young adults assessed with magnetic resonance imaging.

    Science.gov (United States)

    Leung, Jackie; Kosinski, Przemyslaw D; Croal, Paula L; Kassner, Andrea

    2016-05-15

    Cerebrovascular reactivity (CVR) reflects the vasodilatory reserve of cerebral resistance vessels. Normal development in children is associated with significant changes in blood pressure, cerebral blood flow (CBF) and cerebral oxygen metabolism. Therefore, it stands to reason that CVR will also undergo changes during this period. The study acquired magnetic resonance imaging measures of CVR and CBF in healthy children and young adults to trace their changes with age. We found that CVR changes in two phases, increasing with age until the mid-teens, followed by a decrease. Baseline CBF declined steadily with age. We conclude that CVR varies with age during childhood, which prompts future CVR studies involving children to take into account the effect of development. Cerebrovascular reactivity (CVR) reflects the vasculature's ability to accommodate changes in blood flow demand thereby serving as a critical imaging tool for mapping vascular reserve. Normal development is associated with extensive physiological changes in blood pressure, cerebral blood flow and cerebral metabolic rate of oxygen, all of which can affect CVR. Moreover, the evolution of these physiological parameters is most prominent during childhood. Therefore, the aim of this study was to use non-invasive magnetic resonance imaging (MRI) to characterize the developmental trajectories of CVR in healthy children and young adults, and relate them to changes in cerebral blood flow (CBF). Thirty-four healthy subjects (17 males, 17 females; age 9-30 years) underwent CVR assessment using blood oxygen level-dependent MRI in combination with a computer controlled CO2 stimulus. In addition, baseline CBF was measured with a pulsed arterial spin labelling sequence. CVR exhibited a gradual increase with age in both grey and white matter up to 14.7 years. After this break point, a negative correlation with age was detected. Baseline CBF maintained a consistent negative linear correlation across the entire age range

  16. Identifying Gender-Specific Developmental Trajectories of Nonviolent and Violent Delinquency from Adolescence to Young Adulthood

    Science.gov (United States)

    Zheng, Yao; Cleveland, H. Harrington

    2013-01-01

    Most research examining gender differences in developmental trajectories of antisocial behavior does not consider subtypes of antisocial behavior and is difficult to generalize due to small nonrepresentative samples. The current study investigated gender difference in developmental trajectories from adolescence to young adulthood while addressing those limitations. Analyses were limited to respondents ages 15 and 16 in wave 1 (16–17 in wave 2, and 21–22 in wave 3) of the National Longitudinal Study of Adolescent Health (n = 6244, 49.5% males). Self-report nonviolent and violent delinquencies were simultaneously entered into latent class analysis. Four latent classes were identified: low, desister, decliner, and chronic (male-only). In addition to finding a male-specific chronic class, gender differences included differences in levels of nonviolent and violent delinquency between synonymous classes of males and females, and differences in prevalence of classes across genders. Neighborhood disadvantage and family support predicted trajectories. PMID:23375843

  17. Developmental Trajectory of Motor Deficits in Preschool Children with ADHD.

    Science.gov (United States)

    Sweeney, Kristie L; Ryan, Matthew; Schneider, Heather; Ferenc, Lisa; Denckla, Martha Bridge; Mark Mahone, E

    2018-05-14

    Motor deficits persisting into childhood (>7 years) are associated with increased executive and cognitive dysfunction, likely due to parallel neural circuitry. This study assessed the longitudinal trajectory of motor deficits in preschool children with ADHD, compared to typically developing (TD) children, in order to identify individuals at risk for anomalous neurological development. Participants included 47 children (21 ADHD, 26 TD) ages 4-7 years who participated in three visits (V1, V2, V3), each one year apart (V1=48-71 months, V2=60-83 months, V3=72-95 months). Motor variables assessed included speed (finger tapping and sequencing), total overflow, and axial movements from the Revised Physical and Neurological Examination for Subtle Signs (PANESS). Effects for group, visit, and group-by-visit interaction were examined. There were significant effects for group (favoring TD) for finger tapping speed and total axial movements, visit (performance improving with age for all 4 variables), and a significant group-by-visit interaction for finger tapping speed. Motor speed (repetitive finger tapping) and quality of axial movements are sensitive markers of anomalous motor development associated with ADHD in children as young as 4 years. Conversely, motor overflow and finger sequencing speed may be less sensitive in preschool, due to ongoing wide variations in attainment of these milestones.

  18. I. INTRODUCTION: MOVING THROUGH ADOLESCENCE: DEVELOPMENTAL TRAJECTORIES OF AFRICAN AMERICAN AND EUROPEAN AMERICAN YOUTH.

    Science.gov (United States)

    Gutman, Leslie Morrison; Peck, Stephen C; Malanchuk, Oksana; Sameroff, Arnold J; Eccles, Jacquelynne S

    2017-12-01

    In this monograph, we investigate the developmental trajectories of a predominantly middle-class, community-based sample of European American and African American adolescents growing up in urban, suburban, and rural areas in Maryland, United States. Within risk-protection and positive youth development frameworks, we selected developmental measures based on the normative tasks of adolescence and the most widely studied indicators in the three major contexts of development: families, peer groups, and schools. Using hierarchical linear growth models, we estimated adolescents' growth trajectories from ages 12 to 20 with variation accounted for by socioeconomic status (SES), gender, race/ethnicity, and the gender by race/ethnicity interaction. In general, the results indicate that: (a) periods of greatest risk and positive development depended on the time frame and outcome being examined and (b) on average, these adolescents demonstrated much stronger evidence of positive than problematic development, even at their most vulnerable times. Absolute levels of their engagement in healthy behaviors, supportive relationships with parents and friends, and positive self-perceptions and psychological well-being were much higher than their reported angry and depressive feelings, engagement in risky behaviors, and negative relationships with parents and peers. We did not find evidence to support the idea that adolescence is a time of heightened risk. Rather, on average, these adolescents experienced relatively stable and developmentally healthy trajectories for a wide range of characteristics, behaviors, and relationships, with slight increases or decreases at different points in development that varied according to domain. Developmental trajectories differed minimally by SES but in some expected ways by gender and race/ethnicity, although these latter differences were not very marked. Overall, most of the young people navigated through their adolescence and arrived at young

  19. Motor competence and its effect on positive developmental trajectories of health

    OpenAIRE

    Robinson, L.E.; Stodden, David F.; Barnett, L.M.; Lopes, Vítor P.; Logan, S.W.; Rodrigues, Luis Paulo; D'Hondt, E.

    2015-01-01

    In 2008, Stodden and colleagues took a unique developmental approach toward addressing the potential role of motor competence in promoting positive or negative trajectories of physical activity, health-related fitness, and weight status. The conceptual model proposed synergistic relationships among physical activity, motor competence, perceived motor competence, health-related physical fit- ness, and obesity with associations hypothesized to strengthen over time. At the ...

  20. Developmental Trajectories in Children With and Without Autism Spectrum Disorders: The First 3 Years

    OpenAIRE

    Landa, Rebecca J.; Stuart, Elizabeth A.; Gross, Alden L.; Faherty, Ashley

    2012-01-01

    Retrospective studies indicate 2 major classes of autism spectrum disorder (ASD) onset: early and later, after a period of relatively healthy development. This prospective, longitudinal study examined social, language, and motor trajectories in 235 children with and without a sibling with autism, ages 6–36 months. Children were grouped as: ASD identified by 14 months, ASD identified after 14 months, and no ASD. Despite groups’ initial similar developmental level at 6 months, ASD groups exhibi...

  1. Parent-child relationships of boys in different offending trajectories. A developmental perspective

    Science.gov (United States)

    Keijsers, Loes; Loeber, Rolf; Branje, Susan; Meeus, Wim

    2012-01-01

    Background This study tested the theoretical assumption that transformations of parent-child relationships in late childhood and adolescence would differ for boys following different offending trajectories. Methods Using longitudinal multiinformant data of 503 boys (ages 7–19), we conducted Growth Mixture Modeling to extract offending trajectories. Developmental changes in child reports of parent-child joint activities and relationship quality were examined using Latent Growth Curves. Results Five offending trajectories were found: non-offenders, moderate childhood offenders, adolescent-limited offenders, serious childhood offenders, and serious persistent offenders. Non-offenders reported high and stable levels of relationship quality between age 10 and 16. Adolescent-limited offenders reported a similarly high relationship quality as non-offenders at ages 7 and 10, but a lower and decreasing relationship quality in adolescence. Compared with non-offenders, serious persistent offenders reported poorer parent-child relationship quality at all ages, and a decreasing relationship quality in adolescence. Serious persistent offenders and adolescent-limited offenders reported similar levels and changes in parent-child relationship quality in adolescence. Although serious persistent offenders reported fewer joint activities at age 10 and 13 than non-offenders, a similar linear decrease in joint activities in early to middle adolescence was found for boys in each trajectory. Conclusion Developmental changes in parent-child relationship quality differ for different types of offenders. This finding has scientific and practical implications. PMID:22816682

  2. Developmental Trajectory of Number Acuity Reveals a Severe Impairment in Developmental Dyscalculia

    Science.gov (United States)

    Piazza, Manuela; Facoetti, Andrea; Trussardi, Anna Noemi; Berteletti, Ilaria; Conte, Stefano; Lucangeli, Daniela; Dehaene, Stanisalas; Zorzi, Marco

    2010-01-01

    Developmental dyscalculia is a learning disability that affects the acquisition of knowledge about numbers and arithmetic. It is widely assumed that numeracy is rooted on the "number sense", a core ability to grasp numerical quantities that humans share with other animals and deploy spontaneously at birth. To probe the links between number sense…

  3. Developmental trajectories of resting EEG power: an endophenotype of autism spectrum disorder.

    Directory of Open Access Journals (Sweden)

    Adrienne L Tierney

    Full Text Available Current research suggests that autism spectrum disorder (ASD is characterized by asynchronous neural oscillations. However, it is unclear whether changes in neural oscillations represent an index of the disorder or are shared more broadly among both affected and unaffected family members. Additionally, it remains unclear how early these differences emerge in development and whether they remain constant or change over time. In this study we examined developmental trajectories in spectral power in infants at high- or low-risk for ASD. Spectral power was extracted from resting EEG recorded over frontal regions of the scalp when infants were 6, 9, 12, 18 and 24 months of age. We used multilevel modeling to assess change over time between risk groups in the delta, theta, low alpha, high alpha, beta, and gamma frequency bands. The results indicated that across all bands, spectral power was lower in high-risk infants as compared to low-risk infants at 6-months of age. Furthermore high-risk infants showed different trajectories of change in spectral power in the subsequent developmental window indicating that not only are the patterns of change different, but that group differences are dynamic within the first two years of life. These findings remained the same after removing data from a subset of participants who displayed ASD related behaviors at 24 or 36 months. These differences in the nature of the trajectories of EEG power represent important endophenotypes of ASD.

  4. Altered Developmental Trajectories for Impulsivity and Sensation Seeking among Adolescent Substance Users

    Science.gov (United States)

    Charles, Nora E.; Ryan, Stacy R.; Bray, Bethany C.; Mathias, Charles W.; Acheson, Ashley; Dougherty, Donald M.

    2016-01-01

    A number of studies have associated impulsivity and sensation seeking with level of substance use and risk for developing a substance use disorder. These relationships may be particularly apparent during adolescence, when developmental changes in impulsivity and sensation seeking occur at the same time as increased opportunities for substance use. To examine this, the current study measured impulsivity and sensation seeking from pre-adolescence to mid-adolescence in a sample of youth, the majority of whom were identified as being at risk for developing a substance use disorder based on their family history of substance use disorders. Youth were separated into those who did (n = 117) and did not (n = 269) initiate substance use by mid-adolescence. Results showed that substance users were more impulsive and more sensation seeking during pre-adolescence, prior to any significant substance use, and that greater sensation seeking in pre-adolescence was related to heavier substance use by mid-adolescence. In addition, developmental trajectories for substance-using youth showed a greater increase in sensation seeking but a more modest decrease in impulsivity from pre-adolescence to mid-adolescence. Taken together, these results indicate that increased impulsivity and sensation seeking is apparent in adolescent substance users as early as pre-adolescence, that the difference between substance users and non-users becomes larger across early adolescence as their developmental trajectories diverge, and that greater sensation seeking in pre-adolescence may predict increased substance use by mid-adolescence. PMID:27174219

  5. Interpersonal Callousness from Childhood to Adolescence: Developmental Trajectories and Early Risk Factors.

    Science.gov (United States)

    Byrd, Amy L; Hawes, Samuel W; Loeber, Rolf; Pardini, Dustin A

    2018-01-01

    Youth with a callous interpersonal style, consistent with features of adult psychopathy (e.g., lack of guilt, deceitful), are at risk for exhibiting severe and protracted antisocial behaviors. However, no studies have examined changes that occur in interpersonal callousness (IC) from childhood to adolescence, and little is known about the influence of early child, social, and contextual factors on trajectories of IC. The current study examined distinct patterns of IC across childhood and adolescence and associations with early risk factors. Participants were an at-risk sample of 503 boys (56% African American) assessed annually from around ages 7-15. Analyses examined child (anger dysregulation, fearfulness), social (peer, family, maltreatment), and contextual (psychosocial adversity) factors associated with teacher-reported IC trajectories across childhood and adolescence. Using latent class growth analysis, five trajectories of IC were identified (early-onset chronic, childhood-limited, adolescent-onset, moderate, low). Approximately 10% of boys followed an early-onset chronic trajectory, and a roughly equal percent of youth followed childhood-limited trajectory (10%) or an adolescent-onset trajectory (12%) of IC across development. Specifically, half of the boys with high IC in childhood did not continue to exhibit significant levels of these features into adolescence, whereas an equal proportion of youth with low IC in childhood demonstrated increasing levels during the transition to adolescence. Boys in the early-onset chronic group were characterized by the most risk factors and were differentiated from those with childhood-limited and adolescent-onset IC only by higher conduct problems, fearlessness, and emotional abuse/neglect. Findings are discussed in terms of developmental models of IC and several avenues for early targeted interventions.

  6. CT of Normal Developmental and Variant Anatomy of the Pediatric Skull: Distinguishing Trauma from Normality.

    Science.gov (United States)

    Idriz, Sanjin; Patel, Jaymin H; Ameli Renani, Seyed; Allan, Rosemary; Vlahos, Ioannis

    2015-01-01

    The use of computed tomography (CT) in clinical practice has been increasing rapidly, with the number of CT examinations performed in adults and children rising by 10% per year in England. Because the radiology community strives to reduce the radiation dose associated with pediatric examinations, external factors, including guidelines for pediatric head injury, are raising expectations for use of cranial CT in the pediatric population. Thus, radiologists are increasingly likely to encounter pediatric head CT examinations in daily practice. The variable appearance of cranial sutures at different ages can be confusing for inexperienced readers of radiologic images. The evolution of multidetector CT with thin-section acquisition increases the clarity of some of these sutures, which may be misinterpreted as fractures. Familiarity with the normal anatomy of the pediatric skull, how it changes with age, and normal variants can assist in translating the increased resolution of multidetector CT into more accurate detection of fractures and confident determination of normality, thereby reducing prolonged hospitalization of children with normal developmental structures that have been misinterpreted as fractures. More important, the potential morbidity and mortality related to false-negative interpretation of fractures as normal sutures may be avoided. The authors describe the normal anatomy of all standard pediatric sutures, common variants, and sutural mimics, thereby providing an accurate and safe framework for CT evaluation of skull trauma in pediatric patients. (©)RSNA, 2015.

  7. Developmental trajectories of brain maturation and behavior: Relevance to major mental illnesses

    Directory of Open Access Journals (Sweden)

    Sedona Lockhart

    2018-05-01

    Full Text Available Adverse events in childhood and adolescence, such as social neglect or drug abuse, are known to lead to behavioral changes in young adulthood. This is particularly true for the subset of people who are intrinsically more vulnerable to stressful conditions. Yet the underlying mechanisms for such developmental trajectory from early life insult to aberrant adult behavior remains elusive. Adolescence is a period of dynamic physiological, psychological, and behavioral changes, encompassing a distinct neurodevelopmental stage called the ‘critical period’. During adolescence, the brain is uniquely susceptible to stress. Stress mediators may lead to disturbances to biological processes that can cause permanent alterations in the adult stage, even as severe as the onset of mental illness when paired with genetic risk and environmental factors. Understanding the molecular factors governing the critical period and how stress can disturb the maturation processes will allow for better treatment and prevention of late adolescent/young adult onset psychiatric disorders. Keywords: Adolescence, Critical period, Developmental trajectory, Brain maturation, Adult behavior

  8. Latent class analysis of early developmental trajectory in baby siblings of children with autism.

    Science.gov (United States)

    Landa, Rebecca J; Gross, Alden L; Stuart, Elizabeth A; Bauman, Margaret

    2012-09-01

    Siblings of children with autism (sibs-A) are at increased genetic risk for autism spectrum disorders (ASD) and milder impairments. To elucidate diversity and contour of early developmental trajectories exhibited by sibs-A, regardless of diagnostic classification, latent class modeling was used. Sibs-A (N = 204) were assessed with the Mullen Scales of Early Learning from age 6 to 36 months. Mullen T scores served as dependent variables. Outcome classifications at age 36 months included: ASD (N = 52); non-ASD social/communication delay (broader autism phenotype; BAP; N = 31); and unaffected (N = 121). Child-specific patterns of performance were studied using latent class growth analysis. Latent class membership was then related to diagnostic outcome through estimation of within-class proportions of children assigned to each diagnostic classification. A 4-class model was favored. Class 1 represented accelerated development and consisted of 25.7% of the sample, primarily unaffected children. Class 2 (40.0% of the sample), was characterized by normative development with above-average nonverbal cognitive outcome. Class 3 (22.3% of the sample) was characterized by receptive language, and gross and fine motor delay. Class 4 (12.0% of the sample), was characterized by widespread delayed skill acquisition, reflected by declining trajectories. Children with an outcome diagnosis of ASD were spread across Classes 2, 3, and 4. Results support a category of ASD that involves slowing in early non-social development. Receptive language and motor development is vulnerable to early delay in sibs-A with and without ASD outcomes. Non-ASD sibs-A are largely distributed across classes depicting average or accelerated development. Developmental trajectories of motor, language, and cognition appear independent of communication and social delays in non-ASD sibs-A. © 2012 The Authors. Journal of Child Psychology and Psychiatry © 2012 Association for Child and Adolescent Mental Health.

  9. Reading and visual search: a developmental study in normal children.

    Directory of Open Access Journals (Sweden)

    Magali Seassau

    Full Text Available Studies dealing with developmental aspects of binocular eye movement behaviour during reading are scarce. In this study we have explored binocular strategies during reading and during visual search tasks in a large population of normal young readers. Binocular eye movements were recorded using an infrared video-oculography system in sixty-nine children (aged 6 to 15 and in a group of 10 adults (aged 24 to 39. The main findings are (i in both tasks the number of progressive saccades (to the right and regressive saccades (to the left decreases with age; (ii the amplitude of progressive saccades increases with age in the reading task only; (iii in both tasks, the duration of fixations as well as the total duration of the task decreases with age; (iv in both tasks, the amplitude of disconjugacy recorded during and after the saccades decreases with age; (v children are significantly more accurate in reading than in visual search after 10 years of age. Data reported here confirms and expands previous studies on children's reading. The new finding is that younger children show poorer coordination than adults, both while reading and while performing a visual search task. Both reading skills and binocular saccades coordination improve with age and children reach a similar level to adults after the age of 10. This finding is most likely related to the fact that learning mechanisms responsible for saccade yoking develop during childhood until adolescence.

  10. Culture and the Trajectories of Developmental Pathology: Insights from Control and Information Theories.

    Science.gov (United States)

    Wallace, Rodrick

    2018-06-01

    Cognition in living entities-and their social groupings or institutional artifacts-is necessarily as complicated as their embedding environments, which, for humans, includes a particularly rich cultural milieu. The asymptotic limit theorems of information and control theories permit construction of a new class of empirical 'regression-like' statistical models for cognitive developmental processes, their dynamics, and modes of dysfunction. Such models may, as have their simpler analogs, prove useful in the study and re-mediation of cognitive failure at and across the scales and levels of organization that constitute and drive the phenomena of life. These new models particularly focus on the roles of sociocultural environment and stress, in a large sense, as both trigger for the failure of the regulation of bio-cognition and as 'riverbanks' determining the channels of pathology, with implications across life-course developmental trajectories. We examine the effects of an embedding cultural milieu and its socioeconomic implementations using the 'lenses' of metabolic optimization, control system theory, and an extension of symmetry-breaking appropriate to information systems. A central implication is that most, if not all, human developmental disorders are fundamentally culture-bound syndromes. This has deep implications for both individual treatment and public health policy.

  11. Developmental trajectories of pitch-related music skills in children with Williams syndrome.

    Science.gov (United States)

    Martínez-Castilla, Pastora; Rodríguez, Manuel; Campos, Ruth

    2016-01-01

    The study of music cognition in Williams syndrome (WS) has resulted in theoretical debates regarding cognitive modularity and development. However, no research has previously investigated the development of music skills in this population. In this study, we used the cross-sectional developmental trajectories approach to assess the development of pitch-related music skills in children with WS compared with typically developing (TD) peers. Thus, we evaluated the role of change over time on pitch-related music skills and the developmental relationships between music skills and different cognitive areas. In the TD children, the pitch-related music skills improved with chronological age and cognitive development. In the children with WS, developmental relationships were only found between several pitch-related music skills and specific cognitive processes. We also found non-systematic relationships between chronological age and the pitch-related music skills, stabilization in the level reached in music when cognitive development was considered, and uneven associations between cognitive and music skills. In addition, the TD and WS groups differed in their patterns of pitch-related music skill development. These results suggest that the development of pitch-related music skills in children with WS is atypical. Our findings stand in contrast with the views that claim innate modularity for music in WS; rather, they are consistent with neuroconstructivist accounts. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Understanding Random Effects in Group-Based Trajectory Modeling: An Application of Moffitt’s Developmental Taxonomy

    OpenAIRE

    Saunders, Jessica M.

    2010-01-01

    The group-based trajectory modeling approach is a systematic way of categorizing subjects into different groups based on their developmental trajectories using formal and objective statistical criteria. With the recent advancement in methods and statistical software, modeling possibilities are almost limitless; however, parallel advances in theory development have not kept pace. This paper examines some of the modeling options that are becoming more widespread and how they impact both empiric...

  13. Developmental trajectories of anxious and depressive problems during the transition from childhood to adolescence: personality × parenting interactions.

    Science.gov (United States)

    Prinzie, Peter; van Harten, Leanthe V; Deković, Maja; van den Akker, Alithe L; Shiner, Rebecca L

    2014-11-01

    This study examined separate developmental trajectories of anxious and depressive symptoms from childhood to adolescence (9-15 years) in a community-based sample (N = 290). At three measurement points, mothers and fathers reported on their children's anxious and depressive symptoms, and at Time 1 they reported on lower order child personality facets and on their parenting. By means of growth mixture modeling, three developmental trajectories were identified for anxious symptoms: steady low (82%), moderate increasing-decreasing (5.9%), and high declining groups (12.1%). For depressive symptoms, two developmental trajectories were found: steady low (94.1%) and moderate increasing groups (5.9%). Higher shyness, irritability, and altruism predicted membership in more problematic anxious and depressive groups. The personality facets energy, optimism, compliance, and anxiety were unique predictors for class membership for anxious symptoms, and the effects of shyness, irritability, and compliance were moderated by overreactive parenting. Shyness and irritability increased the probability of following the moderate increasing-decreasing anxiety trajectory, but only in the context of high or average levels of overreactive parenting. Compliance increased the probability of following the moderate increasing-decreasing and high decreasing trajectories in the context of high overreactive parenting. Our results indicate that childhood personality facets differentiate trajectories of anxious and depressive symptoms in theoretically compelling ways.

  14. Hot and cool executive function in children and adolescents with autism spectrum disorder: Cross-sectional developmental trajectories.

    Science.gov (United States)

    Kouklari, Evangelia-Chrysanthi; Tsermentseli, Stella; Monks, Claire P

    2017-10-20

    The development of executive function (EF) in autism spectrum disorder (ASD) has only been investigated using "cool"-cognitive-EF tasks. Little is known about the development of "hot"-affective-EF and whether it follows a similar developmental pathway. This study employed a cross-sectional developmental trajectories approach to examine the developmental changes in cool (working memory, inhibition, and planning) and hot EF (delay discounting and affective decision-making) of ASD participants (n = 79) and controls (n = 91) relative to age and IQ, shedding more light on the hot-cool EF organization. The developmental trajectories of some aspects of cool EF (working memory and planning) differed significantly as a function of age in ASD participants relative to controls. For both hot EFs, no significant age-related changes were found in either group. These findings extend our understanding regarding the maturation of EF from childhood through adolescence in ASD.

  15. Developmental trajectories of DSM-IV symptoms of attention-deficit/hyperactivity disorder: genetic effects, family risk and associated psychopathology.

    Science.gov (United States)

    Larsson, Henrik; Dilshad, Rezin; Lichtenstein, Paul; Barker, Edward D

    2011-09-01

    DSM-IV specifies three ADHD subtypes; the combined, the hyperactive-impulsive and the inattentive. Little is known about the developmental relationships underlying these subtypes. The objective of this study was to describe the development of parent-reported hyperactivity-impulsivity and inattention symptoms from childhood to adolescence and to study their associations with genetic factors, family risk, and later adjustment problems in early adulthood. Data in this study comes from 1,450 twin pairs participating in a population-based, longitudinal twin study. Developmental trajectories were defined using parent-ratings of hyperactivity-impulsivity and inattention symptoms at age 8-9, 13-14, and 16-17. Twin methods were used to explore genetic influences on trajectories. Family risk measures included low socioeconomic status, large family size and divorce. Self-ratings of externalizing and internalizing problems in early adulthood were used to examine adjustment problems related to the different trajectory combinations. We found two hyperactivity-impulsivity trajectories (low, high/decreasing) and two inattention trajectories (low, high/increasing). Twin modeling revealed a substantial genetic component underlying both the hyperactivity-impulsivity and the inattention trajectory. Joint trajectory analyses identified four groups of adolescents with distinct developmental patterns of hyperactivity-impulsivity and inattention: a low/low group, a primarily hyperactive, a primarily inattentive and a combined (high/high) trajectory type. These trajectory combinations showed discriminant relations to adjustment problems in early adulthood. The hyperactive, inattentive and combined trajectory subtypes were associated with higher rates of family risk environments compared to the low/low group. Study results showed that for those on a high trajectory, hyperactivity decreased whereas inattention increased. The combinations of these trajectories lend developmental insight into

  16. Does College Matter for Emerging Adulthood? Comparing Developmental Trajectories of Educational Groups.

    Science.gov (United States)

    Mitchell, Lauren L; Syed, Moin

    2015-11-01

    Critics of emerging adulthood theory have suggested that it only applies to college students, but this assertion has largely gone untested. The purpose of the present study was to compare developmental trajectories of non-students versus college-educated youth in theoretically relevant domains of work, love, and financial independence. Using data from the Youth Development Study (N = 1139, 49.6 % female, 63.3 % White, 10.9 % Southeast Asian, 1.5 % Other Asian, 8.6 % Black, 5.3 % Mixed Race, 4.0 % Latino, 0.8 % Native American), latent growth curve models were fitted to chart each group's development, from ages 14 to 30. Different trajectories were revealed for hours worked, children, and financial dependence on parents, spouses, and government aid. No differences were found in employment rates, marriage rates, or financial dependence on own income. These results provide a clearer picture of emerging adulthood for non-students, and highlight problems with generalizing college student research to all emerging adults.

  17. Developmental trajectories of body mass index among Japanese children and impact of maternal factors during pregnancy.

    Directory of Open Access Journals (Sweden)

    Chiyori Haga

    Full Text Available BACKGROUND: The aims of this study were to 1 determine the distinct patterns of body mass index (BMI trajectories in Japanese children, and 2 elucidate the maternal factors during pregnancy, which contribute to the determination of those patterns. METHODOLOGY/PRINCIPAL FINDINGS: All of the children (1,644 individuals born in Koshu City, Japan, between 1991 and 1998 were followed in a longitudinal study exploring the subjects' BMI. The BMI was calculated 11 times for each child between birth and 12 years of age. Exploratory latent class growth analyses were conducted to identify trajectory patterns of the BMI z-scores. The distribution of BMI trajectories were best characterized by a five-group model for boys and a six-group model for girls. The groups were named "stable thin," "stable average," "stable high average," "progressive overweight," and "progressive obesity" in both sexes; girls were allocated to an additional group called "progressive average." Multinomial logistic regression found that maternal weight, smoking, and skipping breakfast during pregnancy were associated with children included in the progressive obesity pattern rather than the stable average pattern. These associations were stronger for boys than for girls. CONCLUSIONS/SIGNIFICANCE: Multiple developmental patterns in Japanese boys and girls were identified, some of which have not been identified in Western countries. Maternal BMI and some unfavorable behaviors during early pregnancy may impact a child's pattern of body mass development. Further studies to explain the gender and regional differences that were identified are warranted, as these may be important for early life prevention of weight-associated health problems.

  18. Children with differing developmental trajectories of prelinguistic communication skills: language and working memory at age 5.

    Science.gov (United States)

    Määttä, Sira; Laakso, Marja-Leena; Tolvanen, Asko; Ahonen, Timo; Aro, Tuija

    2014-06-01

    In this article, the authors examine the developmental continuity from prelinguistic communication to kindergarten age in language and working memory capacity. Following work outlining 6 groups of children with different trajectories of early communication development (ECD; Määttä, Laakso, Tolvanen, Ahonen, & Aro, 2012), the authors examined their later development by psychometric assessment. Ninety-one children first assessed at ages 12-21 months completed a battery of language and working memory tests at age 5;3 (years;months). Two of the ECD groups previously identified as being at risk for language difficulties continued to show weaker performance at follow-up. Seventy-nine percent of the children with compromised language skills at follow-up were identified on the basis of the ECD groups, but the number of false positives was high. The 2 at-risk groups also differed significantly from the typically developing groups in the measures tapping working memory capacity. In line with the dimensional view of language impairment, the accumulation of early delays predicted the amount of later difficulties; however, at the individual level, the prediction had rather low specificity. The results imply a strong link between language and working memory and call for further studies examining the early developmental interaction between language and memory.

  19. Developmental trajectories of anxious and depressive problems during the transition from childhood to adolescence: personality x parenting interactions

    NARCIS (Netherlands)

    Prinzie, P.; van Harten, L.V.; Deković, M.; van den Akker, A.L.; Shiner, R.L.

    2014-01-01

    This study examined separate developmental trajectories of anxious and depressive symptoms from childhood to adolescence (9-15 years) in a community-based sample (N = 290). At three measurement points, mothers and fathers reported on their children's anxious and depressive symptoms, and at Time 1

  20. Developmental trajectories of anxious and depressive problems during the transition from childhood to adolescence: Personality × Parenting interactions

    NARCIS (Netherlands)

    Prinzie, P.; Harten, L. van; Deković, M.; Akker, A.L. van den; Shiner, R.L.

    2014-01-01

    This study examined separate developmental trajectories of anxious and depressive symptoms from childhood to adolescence (9–15 years) in a community-based sample (N = 290). At three measurement points, mothers and fathers reported on their children's anxious and depressive symptoms, and at Time 1

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

    Science.gov (United States)

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

    2011-01-01

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

  2. Developmental trajectories of anxious and depressive problems during the transition from childhood to adolescence : Personality x Parenting interactions

    NARCIS (Netherlands)

    Prinzie, Peter|info:eu-repo/dai/nl/26906110X; van Harten, Leanthe V.; Dekovic, Maja|info:eu-repo/dai/nl/088030563; van den Akker, Alithe L.|info:eu-repo/dai/nl/315028424; Shiner, Rebecca L.

    2014-01-01

    This study examined separate developmental trajectories of anxious and depressive symptoms from childhood to adolescence (9-15 years) in a community-based sample (N = 290). At three measurement points, mothers and fathers reported on their children's anxious and depressive symptoms, and at Time 1

  3. Developmental Trajectories of Hand Movements in Typical Infants and Those at Risk of Developmental Disorders: An Observational Study of Kinematics during the First Year of Life

    Directory of Open Access Journals (Sweden)

    Lisa Ouss

    2018-02-01

    are significantly associated with age in cohorts of typical and at-risk infantsdiffer significantly at 5–6 months of age, depending on the context: relating either with an object or a person.Environmental and developmental factors shape the developmental trajectories of hand movements in different cohorts: environment for infants with VIMs; stage of development for premature infants and those with West syndrome; and both factors for infants with orality disorders.The curvature of hand movements specifically reflects atypical development in infants with West syndrome when developmental age is considered.We aimed to discriminate between typical and atypical developmental trajectory patterns of at-risk infants in an interactive setting in this observational and longitudinal study, with the assumption that hand movements (HM reflect preverbal communication and its disorders. We examined the developmental trajectories of HM in five cohorts of at-risk infants and one control cohort, followed from ages 2 to 10 months: 25 West syndrome (WS, 13 preterm birth (PB, 16 orality disorder (OD, 14 with visually impaired mothers (VIM, 7 early hospitalization (EH, and 19 typically developing infants (TD. Video-recorded data were collected in three different structured interactive contexts. Descriptors of the hand motion were used to examine the extent to which HM were associated with age and cohort. We obtained four principal results: (i the kinematics of HM (spatial use, curvature, acceleration, and velocity were significantly associated with age in all cohorts; (ii HM significantly differed at 5–6 months of age in TD infants, depending on the context; (iii environmental and developmental factors shaped the developmental trajectories of HM in different cohorts: environment for VIM, development for PB and WS, and both factors for OD and; (iv the curvatures of HM showed atypical development in WS infants when developmental age was considered. These findings support the importance

  4. Early developmental influences on self-esteem trajectories from adolescence through adulthood: Impact of birth weight and motor skills.

    Science.gov (United States)

    Poole, Kristie L; Schmidt, Louis A; Ferro, Mark A; Missiuna, Cheryl; Saigal, Saroj; Boyle, Michael H; Van Lieshout, Ryan J

    2018-02-01

    While the trajectory of self-esteem from adolescence to adulthood varies from person to person, little research has examined how differences in early developmental processes might affect these pathways. This study examined how early motor skill development interacted with preterm birth status to predict self-esteem from adolescence through the early 30s. We addressed this using the oldest known, prospectively followed cohort of extremely low birth weight (self-report, and self-esteem was reported during three follow-up periods (age 12-16, age 22-26, and age 29-36). We found that birth weight status moderated the association between early motor skills and self-esteem. Stable over three decades, the self-esteem of normal birth weight participants was sensitive to early motor skills such that those with poorer motor functioning manifested lower self-esteem, while those with better motor skills manifested higher self-esteem. Conversely, differences in motor skill development did not affect the self-esteem from adolescence to adulthood in individuals born at extremely low birth weight. Early motor skill development may exert differential effects on self-esteem, depending on whether one is born at term or prematurely.

  5. White matter developmental trajectories associated with persistence and recovery of childhood stuttering.

    Science.gov (United States)

    Chow, Ho Ming; Chang, Soo-Eun

    2017-04-08

    Stuttering affects the fundamental human ability of fluent speech production, and can have a significant negative impact on an individual's psychosocial development. While the disorder affects about 5% of all preschool children, approximately 80% of them recover naturally within a few years of stuttering onset. The pathophysiology and neuroanatomical development trajectories associated with persistence and recovery of stuttering are still largely unknown. Here, the first mixed longitudinal diffusion tensor imaging (DTI) study of childhood stuttering has been reported. A total of 195 high quality DTI scans from 35 children who stutter (CWS) and 43 controls between 3 and 12 years of age were acquired, with an average of three scans per child, each collected approximately a year apart. Fractional anisotropy (FA), a measure reflecting white matter structural coherence, was analyzed voxel-wise to examine group and age-related differences using a linear mixed-effects (LME) model. Results showed that CWS exhibited decreased FA relative to controls in the left arcuate fasciculus, underlying the inferior parietal and posterior temporal areas, and the mid body of corpus callosum. Further, white matter developmental trajectories reflecting growth rate of these tract regions differentiated children with persistent stuttering from those who recovered from stuttering. Specifically, a reduction in FA growth rate (i.e., slower FA growth with age) in persistent children relative to fluent controls in the left arcuate fasciculus and corpus callosum was found, which was not evident in recovered children. These findings provide first glimpses into the possible neural mechanisms of onset, persistence, and recovery of childhood stuttering. Hum Brain Mapp, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  6. Effects of the SAFE Children preventive intervention on developmental trajectories of attention-deficit/hyperactivity disorder symptoms.

    Science.gov (United States)

    Fowler, Patrick J; Henry, David B; Schoeny, Michael; Gorman-Smith, Deborah; Tolan, Patrick H

    2014-11-01

    This study examined whether a family-based preventive intervention for inner-city children entering the first grade could alter the developmental course of attention-deficit/hyperactivity disorder (ADHD) symptoms. Participants were 424 families randomly selected and randomly assigned to a control condition (n = 192) or Schools and Families Educating Children (SAFE) Children (n = 232). SAFE Children combined family-focused prevention with academic tutoring to address multiple developmental-ecological needs. A booster intervention provided in the 4th grade to randomly assigned children in the initial intervention (n =101) evaluated the potential of increasing preventive effects. Follow-up occurred over 5 years with parents and teachers reporting on attention problems. Growth mixture models identified multiple developmental trajectories of ADHD symptoms. The initial phase of intervention placed children on more positive developmental trajectories for impulsivity and hyperactivity, demonstrating the potential for ADHD prevention in at-risk youth, but the SAFE Children booster had no additional effect on trajectory or change in ADHD indicators.

  7. Motor Competence and its Effect on Positive Developmental Trajectories of Health.

    Science.gov (United States)

    Robinson, Leah E; Stodden, David F; Barnett, Lisa M; Lopes, Vitor P; Logan, Samuel W; Rodrigues, Luis Paulo; D'Hondt, Eva

    2015-09-01

    In 2008, Stodden and colleagues took a unique developmental approach toward addressing the potential role of motor competence in promoting positive or negative trajectories of physical activity, health-related fitness, and weight status. The conceptual model proposed synergistic relationships among physical activity, motor competence, perceived motor competence, health-related physical fitness, and obesity with associations hypothesized to strengthen over time. At the time the model was proposed, limited evidence was available to support or refute the model hypotheses. Over the past 6 years, the number of investigations exploring these relationships has increased significantly. Thus, it is an appropriate time to examine published data that directly or indirectly relate to specific pathways noted in the conceptual model. Evidence indicates that motor competence is positively associated with perceived competence and multiple aspects of health (i.e., physical activity, cardiorespiratory fitness, muscular strength, muscular endurance, and a healthy weight status). However, questions related to the increased strength of associations across time and antecedent/consequent mechanisms remain. An individual's physical and psychological development is a complex and multifaceted process that synergistically evolves across time. Understanding the most salient factors that influence health and well-being and how relationships among these factors change across time is a critical need for future research in this area. This knowledge could aid in addressing the declining levels of physical activity and fitness along with the increasing rates of obesity across childhood and adolescence.

  8. Early adolescent outcomes of joint developmental trajectories of problem behavior and IQ in childhood.

    Science.gov (United States)

    Flouri, Eirini; Papachristou, Efstathios; Midouhas, Emily; Joshi, Heather; Ploubidis, George B; Lewis, Glyn

    2018-04-16

    General cognitive ability (IQ) and problem behavior (externalizing and internalizing problems) are variable and inter-related in children. However, it is unknown how they co-develop in the general child population and how their patterns of co-development may be related to later outcomes. We carried out this study to explore this. Using data from 16,844 Millennium Cohort Study children, we fitted three-parallel-process growth mixture models to identify joint developmental trajectories of internalizing, externalizing and IQ scores at ages 3-11 years. We then examined their associations with age 11 outcomes. We identified a typically developing group (83%) and three atypical groups, all with worse behavior and ability: children with improving behavior and low (but improving in males) ability (6%); children with persistently high levels of problems and low ability (5%); and children with worsening behavior and low ability (6%). Compared to typically developing children, the latter two groups were more likely to show poor decision-making, be bullies or bully victims, engage in antisocial behaviors, skip and dislike school, be unhappy and have low self-esteem. By contrast, children (especially males) in the improver group had outcomes that were similar to, or even better than, those of their typically developing peers. These findings encourage the development of interventions to target children with both cognitive and behavioral difficulties.

  9. Digital Inequality and Developmental Trajectories of Low-income, Immigrant, and Minority Children.

    Science.gov (United States)

    Katz, Vikki S; Gonzalez, Carmen; Clark, Kevin

    2017-11-01

    Children growing up in the United States today are more ethnically and racially diverse than at any time in the nation's history. Because of rising income inequality, almost half of the 72 million children in the United States are also growing up in low-income families, with immigrant and children of color disproportionately likely to be within their ranks. Children in low-income households are more likely to face a number of social challenges, including constrained access to the Internet and devices that connect to it (ie, digital inequality), which can exacerbate other, more entrenched disparities between them and their more privileged counterparts. Although the American Academy of Pediatrics' new guidelines encourage clinicians to reduce children's overexposure to technology, we argue for a more nuanced approach that also considers how digital inequality can reduce low-income children's access to a range of social opportunities. We review previous research on how digital inequality affects children's learning and development and identify areas where more research is needed on how digital inequality relates to specific aspects of children's developmental trajectories, and to identify what interventions at the family, school, and community levels can mitigate the adverse effects of digital inequality as children move through their formal schooling. On the basis of the evidence to date, we conclude with guidelines for clinicians related to supporting digital connectivity and more equitable access to social opportunity for the increasingly diverse population of children growing up in the United States. Copyright © 2017 by the American Academy of Pediatrics.

  10. Developmental trajectories of brain maturation and behavior: Relevance to major mental illnesses.

    Science.gov (United States)

    Lockhart, Sedona; Sawa, Akira; Niwa, Minae

    2018-05-01

    Adverse events in childhood and adolescence, such as social neglect or drug abuse, are known to lead to behavioral changes in young adulthood. This is particularly true for the subset of people who are intrinsically more vulnerable to stressful conditions. Yet the underlying mechanisms for such developmental trajectory from early life insult to aberrant adult behavior remains elusive. Adolescence is a period of dynamic physiological, psychological, and behavioral changes, encompassing a distinct neurodevelopmental stage called the 'critical period'. During adolescence, the brain is uniquely susceptible to stress. Stress mediators may lead to disturbances to biological processes that can cause permanent alterations in the adult stage, even as severe as the onset of mental illness when paired with genetic risk and environmental factors. Understanding the molecular factors governing the critical period and how stress can disturb the maturation processes will allow for better treatment and prevention of late adolescent/young adult onset psychiatric disorders. Copyright © 2018 The Authors. Production and hosting by Elsevier B.V. All rights reserved.

  11. Developmental trajectories of prejudice and tolerance toward immigrants from early to late adolescence.

    Science.gov (United States)

    van Zalk, Maarten Herman Walter; Kerr, Margaret

    2014-10-01

    Adolescence is an important period for the development of relationships between immigrants and non-immigrants, yet little is known about how problematic personality traits affect adolescents' relationships with and attitudes toward immigrants. This work identified the roles of intergroup relationships and one dimension of problematic personality traits, namely callous-unemotional traits, in the development of adolescents' tolerance and prejudice. Three annual measurements of a large community sample (N = 1,542) of non-immigrant adolescents (M age = 15.31 at first measurement; 50.2% girls) were used to show that tolerance and prejudice toward immigrants represent two dimensions with distinct developmental trajectories from early to late adolescence. Callous-unemotional traits predicted fewer decreases in prejudice toward immigrants, yet were not directly associated with tolerance. Intergroup friendships predicted stronger increases in tolerance, which, in turn, predicted decreases in prejudice toward immigrants. Thus, tolerance and prejudice toward immigrants seem to be differentially influenced by social experiences and problematic personality traits.

  12. Searching for biomarkers of developmental toxicity with microarrays: normal eye morphogenesis in rodent embryos

    International Nuclear Information System (INIS)

    Nemeth, Kimberly A.; Singh, Amar V.; Knudsen, Thomas B.

    2005-01-01

    Gene expression arrays reveal the potential linkage of altered gene expression with specific adverse effects leading to disease phenotypes. But how closely do microarray data reflect early physiological or pharmacological measures that predict toxic event(s)? To explore this issue, we have undertaken experiments in early mouse embryos exposed to various teratogens during neurulation stages with the aim of correlating large-scale changes in gene expression across the critical period during exposure. This study reports some of the large-scale changes in gene expression that can be detected in the optic rudiment of the developing mouse and rat embryo across the window of development during which the eye is exceedingly sensitive to teratogen-induced micro-/anophthalmia. Microarray analysis was performed on RNA from the headfold or ocular region at the optic vesicle and optic cup stages when the ocular primordium is enriched for Pax-6, a master control gene for eye morphogenesis. Statistical selection of differentially regulated genes and various clustering techniques identified groups of genes in upward or downward trajectories in the normal optic primordium during early eye development in mouse and rat species. We identified 165 genes with significant differential expression during eye development, and a smaller subset of 58 genes that showed a tight correlation between mouse-rat development. Significantly over-represented functional categories included fatty acid metabolism (up-regulated) and glycolysis (down-regulated). From studies such as these that benchmark large-scale gene expression during normal embryonic development, we may be able to identify the panel of biomarkers that best correlate with species differences and the risks for developmental toxicity

  13. Developmental trajectories of the fronto-temporal lobes from infancy to early adulthood in healthy individuals.

    Science.gov (United States)

    Tanaka, Chiaki; Matsui, Mie; Uematsu, Akiko; Noguchi, Kyo; Miyawaki, Toshio

    2012-01-01

    Brain development during early life in healthy individuals is rapid and dynamic, indicating that this period plays a very important role in neural and functional development. The frontal and temporal lobes are known to play a particularly important role in cognition. The study of healthy frontal and temporal lobe development in children is therefore of considerable importance. A better understanding of how these brain regions develop could also aid in the diagnosis and treatment of neurodevelopmental disorders. Some developmental studies have used magnetic resonance imaging (MRI) to examine infant brains, but it remains the case that relatively little is known about cortical brain development in the first few years of life. In the present study we examined whole brain, temporal lobe and frontal lobe developmental trajectories from infancy to early adulthood in healthy individuals, considering gender and brain hemisphere differences. We performed a cross-sectional, longitudinal morphometric MRI study of 114 healthy individuals (54 females and 60 males) aged 1 month to 25 years old (mean age ± SD 8.8 ± 6.9). We measured whole brain, temporal and frontal lobe gray matter (GM)/white matter (WM) volumes, following previously used protocols. There were significant non-linear age-related volume changes in all regions. Peak ages of whole brain, temporal lobe and frontal lobe development occurred around pre-adolescence (9-12 years old). GM volumes for all regions increased significantly as a function of age. Peak age was nevertheless lobe specific, with a pattern of earlier peak ages for females in both temporal and frontal lobes. Growth change in whole brain GM volume was larger in males than in females. However, GM volume growth changes for the temporal and frontal lobes showed a somewhat different pattern. GM volume for both temporal and frontal lobes showed a greater increase in females until around 5-6 years old, at which point this tendency reversed (GM volume

  14. Metabolic Syndrome in Obese Men and Women with Binge Eating Disorder: Developmental Trajectories of Eating and Weight-Related Behaviors

    OpenAIRE

    Blomquist, Kerstin K.; Milsom, Vanessa A.; Barnes, Rachel D.; Boeka, Abbe G.; White, Marney A.; Masheb, Robin M.; Grilo, Carlos M.

    2012-01-01

    The metabolic syndrome (MetSyn), characterized by vascular symptoms, is strongly correlated with obesity, weight-related medical diseases and mortality, and has increased commensurately with secular increases in obesity in the U.S. Little is known about the distribution of MetSynin obese patients with binge eating disorder (BED) or its associations with different developmental trajectories of dieting, binge eating, and obesity problems. Further, inconsistencies in the limited data necessitate...

  15. Developmental Trajectories of Social Skills during Early Childhood and Links to Parenting Practices in a Japanese Sample.

    Science.gov (United States)

    Takahashi, Yusuke; Okada, Kensuke; Hoshino, Takahiro; Anme, Tokie

    2015-01-01

    This study used data from a nationwide survey in Japan to model the developmental course of social skills during early childhood. The goals of this study were to identify longitudinal profiles of social skills between 2 and 5 years of age using a group-based trajectory approach, and to investigate whether and to what extent parenting practices at 2 years of age predicted developmental trajectories of social skills during the preschool period. A relatively large sample of boys and girls (N > 1,000) was assessed on three social skill dimensions (Cooperation, Self-control, and Assertion) at four time points (ages 2, 3, 4, and 5), and on four parenting practices (cognitive and emotional involvement, avoidance of restriction and punishment, social stimulation, and social support for parenting) at age 2. The results indicated that for each social skill dimension, group-based trajectory models identified three distinct trajectories: low, moderate, and high. Multinomial regression analysis revealed that parenting practice variables showed differential contributions to development of child social skills. Specifically, Cooperation and Assertion were promoted by cognitive and emotional involvement, Self-control by social stimulation, and Assertion by avoidance of restriction and punishment. Abundant social support for parenting was not associated with higher child social skills trajectories. We found heterogeneity in developmental profiles of social skills during the preschool ages, and we identified parenting practices that contributed to different patterns of social skills development. We discussed the implications of higher-quality parenting practices on the improvement of child social skills across early childhood.

  16. The Developmental Trajectory of Self-Injurious Behaviours in Individuals with Prader Willi Syndrome, Autism Spectrum Disorder and Intellectual Disability

    Directory of Open Access Journals (Sweden)

    Lauren J. Rice

    2016-02-01

    Full Text Available In the present study we examined the nature and developmental trajectory of self-injurious behaviour in Prader Willi syndrome (PWS and autism spectrum disorder (ASD. The development of interventions is greatly aided by understanding gene to behaviour pathways, and this requires an accurate description of the behaviour phenotype, that is, which types and natural history of self-injurious behaviour are more common in PWS and ASD and which are shared with other forms of developmental disability. Self-injury displayed by individuals with PWS and individuals with ASD was compared with that reported in a group of individuals with intellectual disability due to mixed aetiology (ID group. Three self-injurious behaviours (head banging, skin-picking and hitting and/or biting self were measured on five occasions over 18 years using the Developmental Behaviour Checklist (DBC a well-validated caregiver report measure. Rates of skin picking were higher in individuals with PWS and hitting and/or biting self was higher in individuals with ASD compared to the ID group. Rates of head banging were similar across the three groups. Over time, skin-picking and head banging increased with age for individuals with ASD and hitting and/or biting self increased for the PWS group. In the PWS and mixed ID groups head banging decreased with age. These findings suggest that the typology and developmental trajectories of self-injurious behaviours differ between those with PWS and ASD.

  17. Developmental trajectories for attention and working memory in healthy Japanese school-aged children.

    Science.gov (United States)

    Egami, Chiyomi; Yamashita, Yushiro; Tada, Yasuhiro; Anai, Chiduru; Mukasa, Akiko; Yuge, Kotaro; Nagamitsu, Shinichiro; Matsuishi, Toyojiro

    2015-10-01

    The aim of this study was to investigate the developmental trajectories of attention, short-term memory, and working memory in school-aged children using a 10 min test battery of cognitive function. Participants comprised 144 typically developing children (TDC) aged 7-12 years and 24 healthy adults, divided according to age into seven groups (12 males and 12 females for each age group). Participants were assessed using CogHealth, which is a computer-based measure composed of five tasks. We measured attention, short-term memory, and working memory (WM) with visual stimulation. Each task was analyzed for age-related differences in reaction time and accuracy rate. Attention tasks were faster in stages from the age of 7-10 years. Accuracy rate of short-term memory gradually increased from 12 years of age and suddenly increased and continued to increase at 22 years of age. Accuracy rate of working memory increased until 12 years of age. Correlations were found between the ages and reaction time, and between ages and accuracy rate of the tasks. These results indicate that there were rapid improvements in attention, short-term memory, and WM performance between 7 and 10 years of age followed by gradual improvement until 12 years of age. Increase in short-term memory continued until 22 years of age. In our experience CogHealth was an easy and useful measure for the evaluation of cognitive function in school-age children. Copyright © 2015 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

  18. Predictors and the distal outcome of general Internet use: The identification of children's developmental trajectories.

    Science.gov (United States)

    Yu, Jeong Jin; Park, Su Jung

    2017-11-01

    This study examined the predictors and distal outcome in relation to the frequency of online activities and investigated the presence of prototypical trajectories following different patterns of general Internet use over 5 years. The data set consisted of a nationally representative sample of 2,840 fourth graders (M age  = 9.86 years) in South Korea at baseline. Analyses revealed rank-order stability in general Internet use with four latent classes: high stable (5.8%), high quadratic (20.3%), moderate stable (32.7%), and low stable (41.2%). Youth with higher levels of perceived parental monitoring knowledge, friendship closeness, and depressed mood at baseline were more likely to belong to the high stable class, while girls were more likely to be in the high quadratic or moderate stable classes relative to the low stable class. The high stable class had the greatest odds of reporting alcohol use at grade eight, whereas the low stable class had the lowest odds. Statement of contribution What is already known on this subject? Internet usage increases as children progress through to early adolescence and then levels off Longitudinal data have shown that adolescents' greater Internet use is predictive of their higher levels of drinking What does this study add? To explore different developmental pathways of Internet use in relation to its antecedents and distal outcome Early adolescents who spend more time on the Internet have a greater chance of starting to drink The interindividual rank-order stability of general Internet usage exists at least before late childhood. © 2017 The British Psychological Society.

  19. Developmental Trajectories of Peer-Reported Aggressive Behavior: The Role of Friendship Understanding, Friendship Quality, and Friends’ Aggressive Behavior

    Science.gov (United States)

    Malti, Tina; McDonald, Kristina; Rubin, Kenneth H.; Rose-Krasnor, Linda; Booth-LaForce, Cathryn

    2015-01-01

    Objective To investigate developmental trajectories in peer-reported aggressive behavior across the transition from elementary-to-middle school, and whether aggressive behavior trajectories were associated with friendship quality, friends’ aggressive behavior, and the ways in which children think about their friendships. Method Participants included a community sample of 230 5th grade children who were assessed when they made a transition from elementary-to-middle school (6th grade). Peer nominations were used to assess the target child’s and friend’s aggressive behavior. Self- and friend reports were used to measure friendship quality; friendship understanding was assessed via a structured interview. Results General Growth Mixture Modeling (GGMM) revealed three distinct trajectories of peer-reported aggressive behavior across the school transition: low-stable, decreasing, and increasing. Adolescents’ understanding of friendship formation differentiated the decreasing from the low-stable aggressive behavior trajectories, and the understanding of friendship trust differentiated the increasing from the low-stable aggressive and decreasing aggressive behavior trajectories. Conclusions The findings indicated that a sophisticated understanding of friendship may serve as a protective factor for initially aggressive adolescents as they transition into middle school. Promoting a deepened understanding of friendship relations and their role in one’s own and others’ well-being may serve as an important prevention and intervention strategy to reduce aggressive behavior. PMID:26688775

  20. Developmental Trajectories of Peer-Reported Aggressive Behavior: The Role of Friendship Understanding, Friendship Quality, and Friends' Aggressive Behavior.

    Science.gov (United States)

    Malti, Tina; McDonald, Kristina; Rubin, Kenneth H; Rose-Krasnor, Linda; Booth-LaForce, Cathryn

    2015-10-01

    To investigate developmental trajectories in peer-reported aggressive behavior across the transition from elementary-to-middle school, and whether aggressive behavior trajectories were associated with friendship quality, friends' aggressive behavior, and the ways in which children think about their friendships. Participants included a community sample of 230 5 th grade children who were assessed when they made a transition from elementary-to-middle school (6 th grade). Peer nominations were used to assess the target child's and friend's aggressive behavior. Self- and friend reports were used to measure friendship quality; friendship understanding was assessed via a structured interview. General Growth Mixture Modeling (GGMM) revealed three distinct trajectories of peer-reported aggressive behavior across the school transition: low-stable, decreasing, and increasing. Adolescents' understanding of friendship formation differentiated the decreasing from the low-stable aggressive behavior trajectories, and the understanding of friendship trust differentiated the increasing from the low-stable aggressive and decreasing aggressive behavior trajectories. The findings indicated that a sophisticated understanding of friendship may serve as a protective factor for initially aggressive adolescents as they transition into middle school. Promoting a deepened understanding of friendship relations and their role in one's own and others' well-being may serve as an important prevention and intervention strategy to reduce aggressive behavior.

  1. Trajectories of Early Childhood Developmental Skills and Early Adolescent Psychotic Experiences: Findings from the ALSPAC UK Birth Cohort.

    Science.gov (United States)

    Hameed, Mohajer A; Lingam, Raghu; Zammit, Stanley; Salvi, Giovanni; Sullivan, Sarah; Lewis, Andrew J

    2017-01-01

    Objective: The aim of this study was to use prospective data from the Avon Longitudinal Study of Parents and Children (ALSPAC) to examine association between trajectories of early childhood developmental skills and psychotic experiences (PEs) in early adolescence. Method: This study examined data from n = 6790 children from the ALSPAC cohort who participated in a semi-structured interview to assess PEs at age 12. Child development was measured using parental report at 6, 18, 30, and 42 months of age using a questionnaire of items adapted from the Denver Developmental Screening Test - II. Latent class growth analysis was used to generate trajectories over time for measures of fine and gross motor development, social, and communication skills. Logistic regression was used to investigate associations between developmental trajectories in each of these early developmental domains and PEs at age 12. Results: The results provided evidence that decline rather than enduringly poor social (adjusted OR = 1.28, 95% CI = 1.10-1.92, p = 0.044) and communication skills (adjusted OR 1.12, 95% CI = 1.03-1.22, p = 0.010) is predictive of suspected or definite PEs in early adolescence, than those with stable and/or improving skills. Motor skills did not display the same pattern of association; although gender specific effects provided evidence that only declining pattern of fine motor skills was associated with suspected and definite PEs in males compared to females (interaction OR = 1.47, 95% CI = 1.09-1.97, p = 0.012). Conclusion: Findings suggest that decline rather than persistent impairment in social and communication skills were most predictive of PEs in early adolescence. Findings are discussed in terms of study's strengths, limitations, and clinical implications.

  2. Prenatal exposure to disaster-related traumatic stress and developmental trajectories of temperament in early childhood: Superstorm Sandy pregnancy study.

    Science.gov (United States)

    Zhang, Wei; Rajendran, Khushmand; Ham, Jacob; Finik, Jackie; Buthmann, Jessica; Davey, Kei; Pehme, Patricia M; Dana, Kathryn; Pritchett, Alexandra; Laws, Holly; Nomura, Yoko

    2018-07-01

    Little is known about the impact of prenatal maternal stress (PNMS) on the developmental trajectory of temperament and few studies have been able to incorporate a natural disaster as a quasi-experimental stressor. The current study investigated PNMS related to Superstorm Sandy ('Sandy'), a hurricane that struck the New York metropolitan area in October 2012, in terms of objective exposure during pregnancy, subjective stress reaction as assessed by maternal symptoms of post-traumatic stress, and their impact on the developmental changes in temperament during early childhood. A subsample of 318 mother-child dyads was drawn from the Stress in Pregnancy Study. Temperament was measured at 6, 12, 18, and 24 months of age. Objective exposure was associated with greater High-Intensity Pleasure, Approach, Perceptual Sensitivity and Fearfulness, but lower Cuddliness and Duration of Orientation at 6 months. Objective exposure and its interaction with subjective stress reaction predicted developmental changes in temperament. In particular, objective exposure was linked to greater increases in Activity Level but decreases in High-Intensity Pleasure, Approach, and Fearfulness. The combination of objective exposure and subjective stress reaction was also associated with greater increases in Activity Level. Temperament was measured solely via maternal report. Trimester-specific effects of Sandy on temperament were not examined. This is the first study to examine the effects of prenatal maternal exposure to a natural disaster on trajectories of early childhood temperament. Findings suggest that both objective stress exposure and subjective stress reaction in-utero predict developmental trajectories of temperament in early childhood. Copyright © 2018 Elsevier B.V. All rights reserved.

  3. Trajectories of Early Childhood Developmental Skills and Early Adolescent Psychotic Experiences: Findings from the ALSPAC UK Birth Cohort

    Directory of Open Access Journals (Sweden)

    Mohajer A. Hameed

    2018-01-01

    Full Text Available Objective: The aim of this study was to use prospective data from the Avon Longitudinal Study of Parents and Children (ALSPAC to examine association between trajectories of early childhood developmental skills and psychotic experiences (PEs in early adolescence.Method: This study examined data from n = 6790 children from the ALSPAC cohort who participated in a semi-structured interview to assess PEs at age 12. Child development was measured using parental report at 6, 18, 30, and 42 months of age using a questionnaire of items adapted from the Denver Developmental Screening Test – II. Latent class growth analysis was used to generate trajectories over time for measures of fine and gross motor development, social, and communication skills. Logistic regression was used to investigate associations between developmental trajectories in each of these early developmental domains and PEs at age 12.Results: The results provided evidence that decline rather than enduringly poor social (adjusted OR = 1.28, 95% CI = 1.10–1.92, p = 0.044 and communication skills (adjusted OR 1.12, 95% CI = 1.03–1.22, p = 0.010 is predictive of suspected or definite PEs in early adolescence, than those with stable and/or improving skills. Motor skills did not display the same pattern of association; although gender specific effects provided evidence that only declining pattern of fine motor skills was associated with suspected and definite PEs in males compared to females (interaction OR = 1.47, 95% CI = 1.09–1.97, p = 0.012.Conclusion: Findings suggest that decline rather than persistent impairment in social and communication skills were most predictive of PEs in early adolescence. Findings are discussed in terms of study’s strengths, limitations, and clinical implications.

  4. Trajectories of Early Childhood Developmental Skills and Early Adolescent Psychotic Experiences: Findings from the ALSPAC UK Birth Cohort

    Science.gov (United States)

    Hameed, Mohajer A.; Lingam, Raghu; Zammit, Stanley; Salvi, Giovanni; Sullivan, Sarah; Lewis, Andrew J.

    2018-01-01

    Objective: The aim of this study was to use prospective data from the Avon Longitudinal Study of Parents and Children (ALSPAC) to examine association between trajectories of early childhood developmental skills and psychotic experiences (PEs) in early adolescence. Method: This study examined data from n = 6790 children from the ALSPAC cohort who participated in a semi-structured interview to assess PEs at age 12. Child development was measured using parental report at 6, 18, 30, and 42 months of age using a questionnaire of items adapted from the Denver Developmental Screening Test – II. Latent class growth analysis was used to generate trajectories over time for measures of fine and gross motor development, social, and communication skills. Logistic regression was used to investigate associations between developmental trajectories in each of these early developmental domains and PEs at age 12. Results: The results provided evidence that decline rather than enduringly poor social (adjusted OR = 1.28, 95% CI = 1.10–1.92, p = 0.044) and communication skills (adjusted OR 1.12, 95% CI = 1.03–1.22, p = 0.010) is predictive of suspected or definite PEs in early adolescence, than those with stable and/or improving skills. Motor skills did not display the same pattern of association; although gender specific effects provided evidence that only declining pattern of fine motor skills was associated with suspected and definite PEs in males compared to females (interaction OR = 1.47, 95% CI = 1.09–1.97, p = 0.012). Conclusion: Findings suggest that decline rather than persistent impairment in social and communication skills were most predictive of PEs in early adolescence. Findings are discussed in terms of study’s strengths, limitations, and clinical implications. PMID:29375433

  5. Developmental trajectories of aggression from late childhood through adolescence: similarities and differences across gender.

    Science.gov (United States)

    Xie, Hongling; Drabick, Deborah A G; Chen, Diane

    2011-01-01

    Although numerous investigations of overt aggressive and antisocial trajectories have been undertaken, there is a dearth of literature examining gender differences and similarities in trajectory patterns and their correlates. To address these gaps, we investigated gender differences in the prevalence rates, predictive validity during transition to adulthood, childhood risk factors, and adolescent correlates of different trajectories of teacher-reported overt aggression (i.e., fights, argues, gets in trouble) among 220 participants (116 girls and 104 boys) evaluated annually from grade 4 to grade 12. Four patterns of trajectories were identified: low, increasing (i.e., adolescent-onset), decreasing (i.e., childhood-limited), and high (i.e., childhood-onset). A large proportion of youth, particularly girls, displayed low levels of aggression over time. A small proportion followed the childhood-onset trajectory. Across gender, the childhood-onset trajectory was associated with the highest rates of maladjustment during the transition to adulthood, the highest number of childhood risk factors, and multiple problems during adolescence. The adolescent-onset trajectory was associated with few childhood risk factors, but with high levels of independent status during adolescence. In contrast, the childhood-limited trajectory was associated with several childhood risk factors, but high levels of parental monitoring and school engagement during adolescence. Romantic involvement differentiated the adolescent-onset and childhood-limited trajectories among girls. © 2011 Wiley-Liss, Inc.

  6. Developmental changes in visuo-spatial working memory in normally developing children: event-related potentials study.

    Science.gov (United States)

    Myatchin, Ivan; Lagae, Lieven

    2013-10-01

    Working memory (WM) is very important for normal development. The fronto-parietal neuronal network supporting WM has already been well-studied. Less is known about the cortical activity changes during development of WM. We evaluated the maturation of visual WM network at the electrophysiological level in a group of normally developing children. Multichannel (n=31) event-related potentials (ERP) were measured during a visuo-spatial backmatching task in 69 childrens (6-16 years old). One-backmatching (BM1) and two-backmatching (BM2) tasks were performed. Age-related changes in behavioral parameters (commission and omission errors and reaction times) and ERP parameters (peak amplitudes and latencies) were analyzed between different ages. Clear improvement in performance from young childhood toward adolescence was seen at the behavioral level: decrease of errors and fastening of reaction times. At the electrophysiological level age-related changes were seen in peak latencies and especially in amplitudes. Different peaks have different dynamics in amplitudes and latencies: early peak amplitude decreased and latency shortened with age, which was not always seen in late peaks. This reflects developmental changes in intensity and speed of WM processing. Later peaks were more clearly seen over the right hemisphere in older children, illustrating hemispheric lateralization in visuo-spatial working memory. Our results indicate that not only at the behavioral but also at the electrophysiological level clear age-related dynamics in WM processing can be seen. Furthermore, with ERP we showed that different WM components follow different developmental trajectories. Our work demonstrates that age-related dynamics in intensity and speed of information processing during WM task is reflected in developmental changes in different ERP components. It also states that fronto-parietal visual WM network can be functional even before all its nodes are fully mature. Copyright © 2012 The

  7. Postnatal Developmental Trajectories of Neural Circuits in the Primate Prefrontal Cortex: Identifying Sensitive Periods for Vulnerability to Schizophrenia

    Science.gov (United States)

    Hoftman, Gil D.; Lewis, David A.

    2011-01-01

    Schizophrenia is a disorder of cognitive neurodevelopment with characteristic abnormalities in working memory attributed, at least in part, to alterations in the circuitry of the dorsolateral prefrontal cortex. Various environmental exposures from conception through adolescence increase risk for the illness, possibly by altering the developmental trajectories of prefrontal cortical circuits. Macaque monkeys provide an excellent model system for studying the maturation of prefrontal cortical circuits. Here, we review the development of glutamatergic and γ-aminobutyric acid (GABA)-ergic circuits in macaque monkey prefrontal cortex and discuss how these trajectories may help to identify sensitive periods during which environmental exposures, such as those associated with increased risk for schizophrenia, might lead to the types of abnormalities in prefrontal cortical function present in schizophrenia. PMID:21505116

  8. The developmental trajectory of children's auditory and visual statistical learning abilities: modality-based differences in the effect of age.

    Science.gov (United States)

    Raviv, Limor; Arnon, Inbal

    2017-09-12

    Infants, children and adults are capable of extracting recurring patterns from their environment through statistical learning (SL), an implicit learning mechanism that is considered to have an important role in language acquisition. Research over the past 20 years has shown that SL is present from very early infancy and found in a variety of tasks and across modalities (e.g., auditory, visual), raising questions on the domain generality of SL. However, while SL is well established for infants and adults, only little is known about its developmental trajectory during childhood, leaving two important questions unanswered: (1) Is SL an early-maturing capacity that is fully developed in infancy, or does it improve with age like other cognitive capacities (e.g., memory)? and (2) Will SL have similar developmental trajectories across modalities? Only few studies have looked at SL across development, with conflicting results: some find age-related improvements while others do not. Importantly, no study to date has examined auditory SL across childhood, nor compared it to visual SL to see if there are modality-based differences in the developmental trajectory of SL abilities. We addressed these issues by conducting a large-scale study of children's performance on matching auditory and visual SL tasks across a wide age range (5-12y). Results show modality-based differences in the development of SL abilities: while children's learning in the visual domain improved with age, learning in the auditory domain did not change in the tested age range. We examine these findings in light of previous studies and discuss their implications for modality-based differences in SL and for the role of auditory SL in language acquisition. A video abstract of this article can be viewed at: https://www.youtube.com/watch?v=3kg35hoF0pw. © 2017 John Wiley & Sons Ltd.

  9. A new selective developmental deficit: Impaired object recognition with normal face recognition.

    Science.gov (United States)

    Germine, Laura; Cashdollar, Nathan; Düzel, Emrah; Duchaine, Bradley

    2011-05-01

    Studies of developmental deficits in face recognition, or developmental prosopagnosia, have shown that individuals who have not suffered brain damage can show face recognition impairments coupled with normal object recognition (Duchaine and Nakayama, 2005; Duchaine et al., 2006; Nunn et al., 2001). However, no developmental cases with the opposite dissociation - normal face recognition with impaired object recognition - have been reported. The existence of a case of non-face developmental visual agnosia would indicate that the development of normal face recognition mechanisms does not rely on the development of normal object recognition mechanisms. To see whether a developmental variant of non-face visual object agnosia exists, we conducted a series of web-based object and face recognition tests to screen for individuals showing object recognition memory impairments but not face recognition impairments. Through this screening process, we identified AW, an otherwise normal 19-year-old female, who was then tested in the lab on face and object recognition tests. AW's performance was impaired in within-class visual recognition memory across six different visual categories (guns, horses, scenes, tools, doors, and cars). In contrast, she scored normally on seven tests of face recognition, tests of memory for two other object categories (houses and glasses), and tests of recall memory for visual shapes. Testing confirmed that her impairment was not related to a general deficit in lower-level perception, object perception, basic-level recognition, or memory. AW's results provide the first neuropsychological evidence that recognition memory for non-face visual object categories can be selectively impaired in individuals without brain damage or other memory impairment. These results indicate that the development of recognition memory for faces does not depend on intact object recognition memory and provide further evidence for category-specific dissociations in visual

  10. Developmental Trajectories of Youth Character: A Five-Wave Longitudinal Study of Cub Scouts and Non-Scout Boys.

    Science.gov (United States)

    Wang, Jun; Ferris, Kaitlyn A; Hershberg, Rachel M; Lerner, Richard M

    2015-12-01

    Youth development programs, such as the Boy Scouts of America, aim to develop positive attributes in youth (e.g., character virtues, prosocial behaviors, and positive civic actions), which are necessary for individuals and societies to flourish. However, few developmental studies have focused on how specific positive attributes develop through participation in programs such as the Boy Scouts of America. As part of the Character and Merit Project, this article examined the developmental trajectories of character and other positive attributes, which are of focal concern of the Boy Scouts of America and the developmental literature. Data were collected from 1398 Scouts (M = 8.59 years, SD = 1.29 years, Range 6.17-11.92 years) and 325 non-Scout boys (M = 9.06 years, SD = 1.43 years, Range 6.20-11.81 years) over five waves of testing across a two-and-half-year period. Latent growth-curve analyses of self-report survey data examined the developmental trajectories of the attributes. Older youth rated themselves lower than younger participants on helpfulness, reverence, thriftiness, and school performance. However, all youth had moderately high self-ratings on all the attributes. Across waves, Scouts' self-ratings increased significantly for cheerfulness, helpfulness, kindness, obedience, trustworthiness, and hopeful future expectations. Non-Scout boys' self-ratings showed no significant change for any attributes except for a significant decrease in religious reverence among non-Scout boys from religious institutions. We discuss implications for positive youth development and for the role of the Boy Scouts of America programming in character development.

  11. Classic and Golli Myelin Basic Protein have distinct developmental trajectories in human visual cortex.

    Science.gov (United States)

    Siu, Caitlin R; Balsor, Justin L; Jones, David G; Murphy, Kathryn M

    2015-01-01

    Traditionally, myelin is viewed as insulation around axons, however, more recent studies have shown it also plays an important role in plasticity, axonal metabolism, and neuroimmune signaling. Myelin is a complex multi-protein structure composed of hundreds of proteins, with Myelin Basic Protein (MBP) being the most studied. MBP has two families: Classic-MBP that is necessary for activity driven compaction of myelin around axons, and Golli-MBP that is found in neurons, oligodendrocytes, and T-cells. Furthermore, Golli-MBP has been called a "molecular link" between the nervous and immune systems. In visual cortex specifically, myelin proteins interact with immune processes to affect experience-dependent plasticity. We studied myelin in human visual cortex using Western blotting to quantify Classic- and Golli-MBP expression in post-mortem tissue samples ranging in age from 20 days to 80 years. We found that Classic- and Golli-MBP have different patterns of change across the lifespan. Classic-MBP gradually increases to 42 years and then declines into aging. Golli-MBP has early developmental changes that are coincident with milestones in visual system sensitive period, and gradually increases into aging. There are three stages in the balance between Classic- and Golli-MBP expression, with Golli-MBP dominating early, then shifting to Classic-MBP, and back to Golli-MBP in aging. Also Golli-MBP has a wave of high inter-individual variability during childhood. These results about cortical MBP expression are timely because they compliment recent advances in MRI techniques that produce high resolution maps of cortical myelin in normal and diseased brain. In addition, the unique pattern of Golli-MBP expression across the lifespan suggests that it supports high levels of neuroimmune interaction in cortical development and in aging.

  12. Child Maltreatment and Children's Developmental Trajectories in Early- to Middle-Childhood

    Science.gov (United States)

    Font, Sarah A.; Berger, Lawrence M.

    2014-01-01

    Associations between experiencing child maltreatment and adverse developmental outcomes are widely studied, yet conclusions regarding the extent to which effects are bidirectional, and whether they are likely causal, remain elusive. This study uses the Fragile Families and Child Well-Being study, a birth cohort of 4,898 children followed from birth through age 9. Hierarchical linear modeling and structural equation modeling are employed to estimate associations of maltreatment with cognitive and social-emotional well-being. Results suggest that effects of early childhood maltreatment emerge immediately, though developmental outcomes are also affected by newly occurring maltreatment over time. Additionally, findings indicate that children's early developmental scores predict their subsequent probability of experiencing maltreatment, though to a lesser extent than early maltreatment predicts subsequent developmental outcomes. PMID:25521556

  13. Child maltreatment and children's developmental trajectories in early to middle childhood.

    Science.gov (United States)

    Font, Sarah A; Berger, Lawrence M

    2015-01-01

    Associations between experiencing child maltreatment and adverse developmental outcomes are widely studied, yet conclusions regarding the extent to which effects are bidirectional, and whether they are likely causal, remain elusive. This study uses the Fragile Families and Child Wellbeing Study, a birth cohort of 4,898 children followed from birth through age 9. Hierarchical linear modeling and structural equation modeling are employed to estimate associations of maltreatment with cognitive and social-emotional well-being. Results suggest that effects of early childhood maltreatment emerge immediately, though developmental outcomes are also affected by newly occurring maltreatment over time. Additionally, findings indicate that children's early developmental scores predict their subsequent probability of experiencing maltreatment, though to a lesser extent than early maltreatment predicts subsequent developmental outcomes. © 2014 The Authors. Child Development © 2014 Society for Research in Child Development, Inc.

  14. Developmental progression to early adult binge drinking and marijuana use from worsening versus stable trajectories of adolescent ADHD and delinquency

    Science.gov (United States)

    Howard, Andrea L.; Molina, Brooke S. G.; Swanson, James M.; Hinshaw, Stephen P.; Belendiuk, Katherine A.; Harty, Seth C.; Arnold, L. Eugene; Abikoff, Howard B.; Hechtman, Lily; Stehli, Annamarie; Greenhill, Laurence L.; Newcorn, Jeffrey H.; Wigal, Timothy

    2015-01-01

    Aims To examine the association between developmental trajectories of inattention, hyperactivity-impulsivity, and delinquency through childhood and adolescence (ages 8-16) and subsequent binge drinking and marijuana use in early adulthood (age 21). Design Prospective naturalistic follow-up of children with attention-deficit/hyperactivity disorder (ADHD) previously enrolled in a randomized controlled trial (RCT). Treatment-phase assessments occurred at 3, 9, and 14 months after randomization; follow-up assessments occurred at 24 months, 36 months, and 6, 8, and 12 years after randomization. Setting Secondary analysis of data from the Multimodal Treatment Study of ADHD (MTA), a multi-site RCT comparing the effects of careful medication management, intensive behavior therapy, their combination, and referral to usual community care. Participants 579 children with DSM-IV ADHD combined type, aged 7.0 and 9.9 years old at baseline (M=8.5, SD=.80). Measurements Ratings of inattention, hyperactivity-impulsivity, and delinquency were collected from multiple informants at baseline and through the 8-year follow-up. Self-reports of binge drinking and marijuana use were collected at the 12-year follow-up (M age 21). Findings Trajectories of worsening inattention symptoms and delinquency (and less apparent improvement in hyperactivity-impulsivity) were associated with higher rates of early adult binge drinking and marijuana use, compared with trajectories of stable or improving symptoms and delinquency (of 24 comparisons, 22 p-values delinquency during adolescence are associated with increased-levels of early adult substance use; this pattern may reflect a developmental course of vulnerability to elevated substance use in early adulthood. PMID:25664657

  15. Developmental Growth Trajectories in Understanding of Fraction Magnitude from Fourth through Sixth Grade

    Science.gov (United States)

    Resnick, Ilyse; Jordan, Nancy C.; Hansen, Nicole; Rajan, Vinaya; Rodrigues, Jessica; Siegler, Robert S.; Fuchs, Lynn S.

    2016-01-01

    Development of fraction number line estimation was assessed longitudinally over 5 time points between 4th and 6th grades. Although students showed positive linear growth overall, latent class growth analyses revealed 3 distinct growth trajectory classes: Students who were highly accurate from the start and became even more accurate (n = 154);…

  16. Parent-Child Relationships of Boys in Different Offending Trajectories: A Developmental Perspective

    Science.gov (United States)

    Keijsers, Loes; Loeber, Rolf; Branje, Susan; Meeus, Wim

    2012-01-01

    Background: This study tested the theoretical assumption that transformations of parent-child relationships in late childhood and adolescence would differ for boys following different offending trajectories. Methods: Using longitudinal multiinformant data of 503 boys (ages 7-19), we conducted Growth Mixture Modeling to extract offending…

  17. Developmental Trajectories of Chinese Children's Relational and Physical Aggression: Associations with Social-Psychological Adjustment Problems

    Science.gov (United States)

    Kawabata, Yoshito; Tseng, Wan-Ling; Murray-Close, Dianna; Crick, Nicki R.

    2012-01-01

    The purpose of this short-term longitudinal study was to examine Chinese children's trajectories of physical and relational aggression and their association with social-psychological adjustment problems (i.e., depressive symptoms and delinquency) and gender. Fourth and fifth grade children in Taiwan (n = 739, age 9-11) were followed across 1 year.…

  18. Understanding the Gender Gap in School Performance among Low-Income Children: A Developmental Trajectory Analysis

    Science.gov (United States)

    Kingdon, Danielle; Serbin, Lisa A.; Stack, Dale M.

    2017-01-01

    Internationally, girls outperform boys in overall school performance. The gender gap is particularly large among those in at-risk groups, such as children from families at economic disadvantage. This study modeled the academic trajectories of a low-income sample of boys and girls from the Concordia Longitudinal Risk Project across the full course…

  19. The Dens: Normal Development, Developmental Variants and Anomalies, and Traumatic Injuries

    Directory of Open Access Journals (Sweden)

    William T O′Brien

    2015-01-01

    Full Text Available Accurate interpretation of cervical spine imagining can be challenging, especially in children and the elderly. The biomechanics of the developing pediatric spine and age-related degenerative changes predispose these patient populations to injuries centered at the craniocervical junction. In addition, congenital anomalies are common in this region, especially those associated with the axis/dens, due to its complexity in terms of development compared to other vertebral levels. The most common congenital variations of the dens include the os odontoideum and a persistent ossiculum terminale. At times, it is necessary to distinguish normal development, developmental variants, and developmental anomalies from traumatic injuries in the setting of acute traumatic injury. Key imaging features are useful to differentiate between traumatic fractures and normal or variant anatomy acutely; however, the radiologist must first have a basic understanding of the spectrum of normal developmental anatomy and its anatomic variations in order to make an accurate assessment. This review article attempts to provide the basic framework required for accurate interpretation of cervical spine imaging with a focus on the dens, specifically covering the normal development and ossification of the dens, common congenital variants and their various imaging appearances, fracture classifications, imaging appearances, and treatment options.

  20. Personal identity in college and the work context : Developmental trajectories and psychosocial functioning

    NARCIS (Netherlands)

    Luyckx, K.; Klimstra, T.A.; Schwartz, S.J.; Duriez, B.

    2013-01-01

    Personal identity formation represents a core developmental challenge for adolescents and young adults. Because much of the identity literature focuses on college students, it is necessary to conduct a detailed inquiry into the ways in which specific commitment and exploration processes develop over

  1. Children's Competence or Adults' Incompetence: Different Developmental Trajectories in Different Tasks

    Science.gov (United States)

    Furlan, Sarah; Agnoli, Franca; Reyna, Valerie F.

    2013-01-01

    Dual-process theories have been proposed to explain normative and heuristic responses to reasoning and decision-making problems. Standard unitary and dual-process theories predict that normative responses should increase with age. However, research has focused recently on exceptions to this standard pattern, including developmental increases in…

  2. Longitudinal Investigation of Source Memory Reveals Different Developmental Trajectories for Item Memory and Binding

    Science.gov (United States)

    Riggins, Tracy

    2014-01-01

    The present study used a cohort-sequential design to examine developmental changes in children's ability to bind items in memory during early and middle childhood. Three cohorts of children (aged 4, 6, or 8 years) were followed longitudinally for 3 years. Each year, children completed a source memory paradigm assessing memory for items and…

  3. The Developmental Trajectory of Borderline Personality Disorder and Peer Victimisation: Australian Family Carers' Perspectives

    Science.gov (United States)

    Wlodarczyk, Julian; Lawn, Sharon

    2017-01-01

    Victimisation is a traumatic experience linked to development of Borderline personality disorder (BPD). However, there is limited research investigating the developmental journey prior to BPD diagnosis. School environments offer an opportunity for BPD prevention and early intervention. A survey with 19 Australian family carers of people with BPD…

  4. Child Maltreatment and Children's Developmental Trajectories in Early to Middle Childhood

    Science.gov (United States)

    Font, Sarah A.; Berger, Lawrence M.

    2015-01-01

    Associations between experiencing child maltreatment and adverse developmental outcomes are widely studied, yet conclusions regarding the extent to which effects are bidirectional, and whether they are likely causal, remain elusive. This study uses the Fragile Families and Child Wellbeing Study, a birth cohort of 4,898 children followed from birth…

  5. Developmental Trajectories of Anxiety Symptoms in Early Adolescence: The Influence of Anxiety Sensitivity

    OpenAIRE

    Allan, Nicholas P.; Capron, Daniel W.; Lejuez, Carl W.; Reynolds, Elizabeth K.; MacPherson, Laura; Schmidt, Norman B.

    2014-01-01

    Children and adolescents seem to suffer from anxiety disorders at rates similar to adults. Interestingly, anxiety symptoms appear to generally decline over time within children as evidenced by lower rates in early and middle adolescence. There is some evidence that there may be heterogeneous subpopulations of adolescent children with different trajectories of anxiety symptoms, including a class of adolescents with elevated levels of anxiety that do not dissipate over time. Anxiety sensitivity...

  6. Developmental trajectories of anxiety symptoms in early adolescence: the influence of anxiety sensitivity.

    Science.gov (United States)

    Allan, Nicholas P; Capron, Daniel W; Lejuez, Carl W; Reynolds, Elizabeth K; MacPherson, Laura; Schmidt, Norman B

    2014-05-01

    Children and adolescents seem to suffer from anxiety disorders at rates similar to adults. Interestingly, anxiety symptoms appear to generally decline over time within children as evidenced by lower rates in early and middle adolescence. There is some evidence that there may be heterogeneous subpopulations of adolescent children with different trajectories of anxiety symptoms, including a class of adolescents with elevated levels of anxiety that do not dissipate over time. Anxiety sensitivity has been identified as an important risk factor in the development of anxiety psychopathology. This study prospectively examined the development of anxiety symptoms in a sample of 277 adolescents (M age = 11.52; 44 % female, 56 % male) over a 3 year period including the influence of anxiety sensitivity on this development. Further, this study investigated whether there were distinct classes of adolescents based on their anxiety symptom trajectories and including anxiety sensitivity as a predictor. Consistent with other reports, findings indicated an overall decline in anxiety symptoms over time in the sample. However, three classes of adolescents were found with distinct anxiety symptom trajectories and anxiety sensitivity was an important predictor of class membership. Adolescents with elevated anxiety sensitivity scores were more likely to be classified as having high and increasing anxiety symptoms over time versus having moderate to low and decreasing anxiety symptoms over time. There are important implications for identification of adolescents and children who are at risk for the development of an anxiety disorder.

  7. Navigating role forces and the aesthetic|authentic caring dialectic: a novice urban science teacher's developmental trajectory

    Science.gov (United States)

    Rivera Maulucci, Maria S.

    2010-09-01

    Examining role forces and resources available to new teachers is crucial to understanding how teachers use and expand cultural, social, and symbolic resources and how they engage teaching for social justice and caring in urban science education. This critical narrative inquiry explores three levels of story. First, the narratives explore my role as a district science staff developer and my efforts to leverage district resources to improve students' opportunities to learn science. Second, the narratives explore the ways in which a novice science teacher, Tina, navigated role forces and the aesthetic|authentic caring dialectic in a high poverty, urban school. A third level of narrative draws on sociological theories of human interaction to explore role forces and how they shaped Tina's developmental trajectory. I describe how Tina expanded cultural, social, and symbolic resources to enact her teaching role.

  8. Sex differences in the developmental trajectories of impulse control and sensation-seeking from early adolescence to early adulthood.

    Science.gov (United States)

    Shulman, Elizabeth P; Harden, K Paige; Chein, Jason M; Steinberg, Laurence

    2015-01-01

    It has been proposed that high rates of risk-taking in adolescence are partly attributable to patterns of neurobiological development that promote an increase in sensation-seeking tendencies at a time when impulse control is still developing. It is not known, however, whether this pattern is the same for males and females. The present study investigates sex differences in the developmental trajectories of self-reported impulse control and sensation-seeking between the ages of 10 and 25 using longitudinal data from the National Longitudinal Study of Youth 1979 Child and Young Adult Survey (N = 8,270; 49% female; 33% Black, 22% Hispanic, 45% Non-Black, Non-Hispanic). Prior work has found that, consistent with the dual-systems model of adolescent neurobiological development, sensation-seeking rises and falls across this age span, whereas impulse control increases into the 20s. In the present study, we find that this same general pattern holds for both males and females, but with some key differences. As expected, males exhibit higher levels of sensation-seeking and lower levels of impulse control than females. Differences also emerged in the shapes of the developmental trajectories. Females reach peak levels of sensation-seeking earlier than males (consistent with the idea that sensation-seeking is linked to pubertal development) and decline in sensation-seeking more rapidly thereafter. Also, males increase in impulse control more gradually than females. Consequently, sex differences in both impulse control and sensation-seeking increase with age. The findings suggest that the window of heightened vulnerability to risk-taking during adolescence may be greater in magnitude and more protracted for males than for females.

  9. Longitudinal investigation of source memory reveals different developmental trajectories for item memory and binding

    OpenAIRE

    Riggins, Tracy

    2013-01-01

    The present study used a cohort-sequential design to examine developmental changes in children's ability to bind items in memory during early and middle childhood. Three cohorts of children (aged 4, 6, or 8 years) were followed longitudinally for three years. Each year, children completed a source memory paradigm assessing memory for items and binding. Results suggest linear increases in memory for individual items (facts or sources) between 4 and 10 years of age, but that memory for correct ...

  10. 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.

  11. Developmental trajectories and breakdown in F1 interpopulation hybrids of Tribolium castaneum

    Science.gov (United States)

    Drury, Douglas W; Ehmke, Ross C; Jideonwo, Victoria N; Wade, Michael J

    2013-01-01

    When hybrid inviability is an indirect by-product of local adaptation, we expect its degree of severity between pairs of populations to vary and to be sensitive to the environment. While complete reciprocal hybrid inviability is the outcome of the gradual process of local adaptation, it is not representative of the process of accumulation of incompatibility. In the flour beetle, Tribolium castaneum, some pairs of populations exhibit complete, reciprocal F1 hybrid incompatibility while other pairs are fully or partially compatible. We characterize this naturally occurring variation in the degree and timing of expression of the hybrid incompatible phenotype to better understand the number of genes or developmental processes contributing to speciation. We assessed the morphological and developmental variation in four Tribolium castaneum populations and their 12 possible F1 hybrids at each life-history stage from egg to adult. We find that the rate of hybrid larval development is affected in all interpopulation crosses, including those eventually producing viable, fertile adults. Hybrid incompatibility manifests early in development as changes in the duration of instars and diminished success in the transition between instars are relative to the parent populations. Parent populations with similar developmental profiles may produce hybrids with disrupted development. The degree and timing of expression of hybrid inviability depends upon populations crossed, direction of the cross, and environment in which hybrids are raised. Our findings suggest that the coordinated expression of genes involved in transitional periods of development is the underlying cause of hybrid incompatibility in this species. PMID:23919145

  12. Bases, Stages and 'Working Your Way Up': Young People's Talk About Non-Coital Practices and 'Normal' Sexual Trajectories

    OpenAIRE

    Ruth Lewis; Cicely Marston; Kaye Wellings

    2013-01-01

    While the symbolic importance of 'losing your virginity' has been described in many settings, meanings of non-coital sexual experiences, such as oral sex and hand-genital contact, are often missing from theorisation of sexual transitions. Drawing on data from a qualitative mixed methods study with young people aged 16-18 in England (the 'sixteen18 project'), we explore normative expectations about non-coital sex and sexual trajectories. Our study demonstrates how gendered talk about a 'normal...

  13. The developmental trajectory of disruptive behavior in Down syndrome, fragile X syndrome, Prader-Willi syndrome and Williams syndrome.

    Science.gov (United States)

    Rice, Lauren J; Gray, Kylie M; Howlin, Patricia; Taffe, John; Tonge, Bruce J; Einfeld, Stewart L

    2015-06-01

    The aim of this study was to investigate the developmental trajectories of verbal aggression, physical aggression, and temper tantrums in four genetic syndrome groups. Participants were part of the Australian Child to Adult Development Study (ACAD), which collected information from a cohort of individuals with an intellectual disability at five time points over 18 years. Data were examined from a total of 248 people with one of the four following syndromes: Down syndrome, Fragile X syndrome, Prader-Willi syndrome, or Williams syndrome. Changes in behaviors were measured using validated items from the Developmental Behavior Checklist (DBC). The results indicate that, while verbal aggression shows no evidence of diminishing with age, physical aggression, and temper tantrums decline with age before 19 years for people with Down syndrome, Fragile X syndrome, and William syndrome; and after 19 years for people with Prader-Willi syndrome. These findings offer a somewhat more optimistic outlook for people with an intellectual disability than has previously been suggested. Research is needed to investigate the mechanisms predisposing people with PWS to persistence of temper tantrums and physical aggression into adulthood. © 2015 Wiley Periodicals, Inc.

  14. High-resolution SNP array analysis of patients with developmental disorder and normal array CGH results

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    Siggberg Linda

    2012-09-01

    Full Text Available Abstract Background Diagnostic analysis of patients with developmental disorders has improved over recent years largely due to the use of microarray technology. Array methods that facilitate copy number analysis have enabled the diagnosis of up to 20% more patients with previously normal karyotyping results. A substantial number of patients remain undiagnosed, however. Methods and Results Using the Genome-Wide Human SNP array 6.0, we analyzed 35 patients with a developmental disorder of unknown cause and normal array comparative genomic hybridization (array CGH results, in order to characterize previously undefined genomic aberrations. We detected no seemingly pathogenic copy number aberrations. Most of the vast amount of data produced by the array was polymorphic and non-informative. Filtering of this data, based on copy number variant (CNV population frequencies as well as phenotypically relevant genes, enabled pinpointing regions of allelic homozygosity that included candidate genes correlating to the phenotypic features in four patients, but results could not be confirmed. Conclusions In this study, the use of an ultra high-resolution SNP array did not contribute to further diagnose patients with developmental disorders of unknown cause. The statistical power of these results is limited by the small size of the patient cohort, and interpretation of these negative results can only be applied to the patients studied here. We present the results of our study and the recurrence of clustered allelic homozygosity present in this material, as detected by the SNP 6.0 array.

  15. Developmental Trajectories of Boys’ Driven Exercise and Fasting During the Middle School Years

    Science.gov (United States)

    Davis, Heather A.; Guller, Leila; Smith, Gregory T.

    2016-01-01

    Boys appear to engage in eating disorder behavior, particularly nonpurging compensatory behaviors such as driven exercise and fasting, at higher rates than previously thought. Little is known about the development of these behaviors in adolescent boys. In a sample of 631 non-binge eating and non-purging boys studied once in 5th grade and 6 times over the 3 years of middle school (grades 6 through 8), we found that (a) for some youth, driven exercise and fasting were present from grade 6; (b) different boys progressed along different trajectories of engagement in driven exercise and fasting, with some boys engaging in no driven exercise or fasting (65.8% and 83.5%, respectively), some boys engaging in driven exercise and fasting throughout middle school (25.2% and 16.5%, respectively), and other boys discontinuing engagement in driven exercise (9%); (c) 5th grade depression, eating expectancies, and thinness expectancies predicted subsequent trajectory group membership; and (d) boys engaging in driven exercise and fasting in 8th grade remained distressed. Boys’ engagement in driven exercise and fasting behavior merits the attention of researchers and clinicians. PMID:26707543

  16. Social distance and behavioral attributes of developmentally handicapped and normal children.

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    Sherman, L W; Burgess, D E

    1985-12-01

    20 behavioral attributes predicting social distance were examined among 101 junior high school students in six classrooms. The sample included 8 developmentally handicapped students, of whom at least one of each was mainstreamed into each classroom. Subjects were predominantly white, middle-class, suburban midwesterners. A sociometric nomination measure was used to obtain behavioral attribute profiles of the students which were then used to predict a psychometric measure of social distance. Handicapped students were not more socially distant than their normal peers. Factor analysis of the 20 behavioral attributes yielded four factors, three of which were significant predictors of classroom social distance, accounting for better than half the variance in social distance. These were described as Incompetent/Unassertive, Positive/Active/Assertive, and Passive/Unassertive. Social rejection in mainstreamed classrooms is more a function of perceived behavioral attributes than the label developmentally handicapped.

  17. Children’s Competence or Adults’ Incompetence: Different Developmental Trajectories in Different Tasks

    Science.gov (United States)

    S., Furlan; F., Agnoli; V. F., Reyna

    2013-01-01

    Dual-process theories have been proposed to explain normative and heuristic responses to reasoning and decision-making problems. Standard unitary and dual-process theories predict that normative responses should increase with age. However, research has focused recently on exceptions to this standard pattern, including developmental increases in heuristic or intuitive responses. Developmental trends for normative and heuristic responses were investigated for two kinds of causal reasoning (if-only and covariation) problems in two experiments. To investigate the role of superstitious thinking in these developmental trends, in both experiments a superstitious element was added to the problem solved by half the participants. In the first experiment, 90 fifth graders, 99 seventh graders, and 153 adults responded to an if-only problem. Children performed better than adults, with normative responses decreasing and heuristic responses increasing with age. A superstitious jinx intended to reduce heuristic responses had little effect for all age groups. In the second experiment, 276 fifth graders, 344 seventh graders, and 90 adults responded to a covariation-detection problem. When win-loss ratios were equal, adults performed better than children, with normative responses increasing and heuristic responses decreasing with age. When win-loss ratios were strikingly different, however, even the youngest children were able to solve the problems correctly; participants of all ages responded about equally well. When the normative response required recognizing that a good-luck ritual led to better team performance, participants in all age groups responded skeptically that the ritual had no effect, illustrating belief bias. These results are discussed in terms of dual process theories and the development of heuristic (or intuitive) and analytical processes. PMID:23148936

  18. Convergent evolution of alternative developmental trajectories associated with diapause in African and South American killifish.

    Science.gov (United States)

    Furness, Andrew I; Reznick, David N; Springer, Mark S; Meredith, Robert W

    2015-03-07

    Annual killifish adapted to life in seasonally ephemeral water-bodies exhibit desiccation resistant eggs that can undergo diapause, a period of developmental arrest, enabling them to traverse the otherwise inhospitable dry season. Environmental cues that potentially indicate the season can govern whether eggs enter a stage of diapause mid-way through development or skip this diapause and instead undergo direct development. We report, based on construction of a supermatrix phylogenetic tree of the order Cyprinodontiformes and a battery of comparative analyses, that the ability to produce diapause eggs evolved independently at least six times within African and South American killifish. We then show in species representative of these lineages that embryos entering diapause display significant reduction in development of the cranial region and circulatory system relative to direct-developing embryos. This divergence along alternative developmental pathways begins mid-way through development, well before diapause is entered, during a period of purported maximum developmental constraint (the phylotypic period). Finally, we show that entering diapause is accompanied by a dramatic reduction in metabolic rate and concomitant increase in long-term embryo survival. Morphological divergence during the phylotypic period thus allows embryos undergoing diapause to conserve energy by shunting resources away from energetically costly organs thereby increasing survival chances in an environment that necessitates remaining dormant, buried in the soil and surrounded by an eggshell for much of the year. Our results indicate that adaptation to seasonal aquatic environments in annual killifish imposes strong selection during the embryo stage leading to marked diversification during this otherwise conserved period of vertebrate development. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  19. Developmental Trajectories of Religiosity, Sexual Conservatism and Sexual Behavior among Female Adolescents

    Science.gov (United States)

    Aalsma, Matthew C.; Woodrome, Stacy E.; Downs, Sarah M.; Hensel, Devon; Zimet, Gregory D.; Orr, Don P.; Fortenberry, J. Dennis

    2013-01-01

    Understanding the role of socio-sexual cognitions and religiosity on adolescent sexual behavior could guide adolescent sexual health efforts. The present study utilized longitudinal data from 328 young women to assess the role of religion and socio-sexual cognitions on sexual behavior accrual (measuring both coital and non-coital sexual behavior). In the final triple conditional trajectory structural equation model, religiosity declined over time and then increased to baseline levels. Additionally, religiosity predicted decreased sexual conservatism and decreased sexual conservatism predicted increased sexual behavior. The final models are indicative of young women's increasing accrual of sexual experience, decreasing sexual conservatism and initial decreasing religiosity. The results of this study suggest that decreased religiosity affects the accrual of sexual experience through decreased sexual conservatism. Effective strategies of sexual health promotion should include an understanding of the complex role of socio-sexual attitudes with religiosity. PMID:24215966

  20. Developmental trajectories of paediatric headache - sex-specific analyses and predictors.

    Science.gov (United States)

    Isensee, Corinna; Fernandez Castelao, Carolin; Kröner-Herwig, Birgit

    2016-01-01

    Headache is the most common pain disorder in children and adolescents and is associated with diverse dysfunctions and psychological symptoms. Several studies evidenced sex-specific differences in headache frequency. Until now no study exists that examined sex-specific patterns of change in paediatric headache across time and included pain-related somatic and (socio-)psychological predictors. Latent Class Growth Analysis (LCGA) was used in order to identify different trajectory classes of headache across four annual time points in a population-based sample (n = 3 227; mean age 11.34 years; 51.2 % girls). In multinomial logistic regression analyses the influence of several predictors on the class membership was examined. For girls, a four-class model was identified as the best fitting model. While the majority of girls reported no (30.5 %) or moderate headache frequencies (32.5 %) across time, one class with a high level of headache days (20.8 %) and a class with an increasing headache frequency across time (16.2 %) were identified. For boys a two class model with a 'no headache class' (48.6 %) and 'moderate headache class' (51.4 %) showed the best model fit. Regarding logistic regression analyses, migraine and parental headache proved to be stable predictors across sexes. Depression/anxiety was a significant predictor for all pain classes in girls. Life events, dysfunctional stress coping and school burden were also able to differentiate at least between some classes in both sexes. The identified trajectories reflect sex-specific differences in paediatric headache, as seen in the number and type of classes extracted. The documented risk factors can deliver ideas for preventive actions and considerations for treatment programmes.

  1. Developmental trajectories of religiosity, sexual conservatism and sexual behavior among female adolescents.

    Science.gov (United States)

    Aalsma, Matthew C; Woodrome, Stacy E; Downs, Sarah M; Hensel, Devon J; Zimet, Gregory D; Orr, Don P; Fortenberry, J Dennis

    2013-12-01

    Understanding the role of socio-sexual cognitions and religiosity on adolescent sexual behavior could guide adolescent sexual health efforts. The present study utilized longitudinal data from 328 young women to assess the role of religion and socio-sexual cognitions on sexual behavior accrual (measuring both coital and non-coital sexual behavior). In the final triple conditional trajectory structural equation model, religiosity declined over time and then increased to baseline levels. Additionally, religiosity predicted decreased sexual conservatism and decreased sexual conservatism predicted increased sexual behavior. The final models are indicative of young women's increasing accrual of sexual experience, decreasing sexual conservatism and initial decreasing religiosity. The results of this study suggest that decreased religiosity affects the accrual of sexual experience through decreased sexual conservatism. Effective strategies of sexual health promotion should include an understanding of the complex role of socio-sexual attitudes with religiosity. Copyright © 2013 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

  2. Children with Williams syndrome: Developmental trajectories for intellectual abilities, vocabulary abilities, and adaptive behavior.

    Science.gov (United States)

    Mervis, Carolyn B; Pitts, C Holley

    2015-06-01

    To examine longitudinal trajectories of intellectual abilities, single-word vocabulary abilities, and adaptive behavior for 76 children with Williams syndrome (WS) aged 4-15 years, we compared their standard scores (SSs) at two time points approximately 3 years apart on the same standardized measures. At the group level, mean SS declined significantly for 8 of the 12 measures and showed a slight (nonsignificant) increase or decrease for 4 measures. However, for most measures significant changes in SS were found for only a small proportion of the children, with some children evidencing significant declines and a smaller proportion evidencing significant increases. Significant SS changes were most common for adaptive behavior. For all measures, the mean magnitude of SS change was smaller for older children (>7.5 years at Time 1) than for younger children (general population peers who earned the same SS at Time 1, there was little evidence either of regression (loss of skills) or stagnation (failure to increase raw scores). The relations of these results to those of previous smaller-sample longitudinal studies of children with WS and the implications of the findings are considered. © 2015 Wiley Periodicals, Inc.

  3. Differences in center of pressure trajectory between normal and steppage gait

    Science.gov (United States)

    Jamshidi, Nima; Rostami, Mostafa; Najarian, Siamak; Menhaj, Mohammad Bagher; Saadatnia, Mohammad; Salami, Firooz

    2010-01-01

    BACKGROUND: This pilot study aimed to assess the differences in center of pressure trajectory in neuropathic patients with steppage gait. Steppage gait has previously been evaluated by several biomechanical methods, but plantar pressure distribution has been much less studied. The purpose of this study was to analyze the changes in center of pressure trajectory using a force plate. METHODS: The steppage gait group was selected from the patients using drop foot brace (25 male) and the control group was selected from Isfahan university students (20 male). They walked at self- selected speed at a mean of ten trials (+2) to collect the center of pressure using a force plate. Center of pressure patterns were categorized into four patterns based on the center of pressure displacement magnitude (spatial features) through time (temporal features) when the longitudinal axis of the insole was plotted as the Y- axis and the transverse axis of the insole as X- axis during stance phase. RESULTS: The horizontal angle measured from center of pressure linear regression was positive in the control group (4.6 ± 2.4) (p < 0.005), but negative in the patient group (- 2.3 ± 1.6) (p < 0.005). CONCLUSIONS: The finding of this research measured center of pressure trajectory in steppage gait over time, which is useful for designing better shoe sole and also orthopaedic device and better understanding of stability in patients with drop foot. PMID:21526056

  4. Differences in center of pressure trajectory between normal and steppage gait

    Directory of Open Access Journals (Sweden)

    Nima Jamshidi

    2010-01-01

    Full Text Available Background: This pilot study aimed to assess the differences in center of pressure trajectory in neuropathic patients with steppage gait. Steppage gait has previously been evaluated by several biomechanical methods, but plantar pressure distribution has been much less studied. The purpose of this study was to analyze the changes in center of pressure tra-jectory using a force plate. Methods: The steppage gait group was selected from the patients using drop foot brace (25 male and the control group was selected from Isfahan university students (20 male. They walked at self- selected speed at a mean of ten tri-als (+2 to collect the center of pressure using a force plate. Center of pressure patterns were categorized into four pat-terns based on the center of pressure displacement magnitude (spatial features through time (temporal features when the longitudinal axis of the insole was plotted as the Y- axis and the transverse axis of the insole as X- axis during stance phase. Results: The horizontal angle measured from center of pressure linear regression was positive in the control group (4.6 ± 2.4 (p < 0.005, but negative in the patient group (- 2.3 ± 1.6 (p < 0.005. Conclusions: The finding of this research measured center of pressure trajectory in steppage gait over time, which is useful for designing better shoe sole and also orthopaedic device and better understanding of stability in patients with drop foot.

  5. Developmental trajectories of overweight and obesity of US youth through the life course of adolescence to young adulthood

    Directory of Open Access Journals (Sweden)

    Chen X

    2012-03-01

    Full Text Available Xinguang Chen, Kathryn BroganPediatric Prevention Research Center, Wayne State University School of Medicine, Detroit, MI, USAObjective: To detect subgroups with different risks at different ages to develop overweight and obese during the adolescence–young adulthood period.Design: Accelerated longitudinal design and developmental trajectory analysis were used. The likelihoods to become overweight (body mass index [BMI] .25 kg/m2 and obese (BMI .30 kg/m2 were assessed across the life course from the ages of 12 to 28 years.Subjects: Adolescent participants aged 12–17 years (n = 4119 identified in the National Longitudinal Survey of Youth 1997 at baseline were followed up to 2008.Results: Seven overweight risk groups (WG were detected for male and female samples respectively, of which five were closely related to each of the following five periods: (a middle-school ages (19.7% and 12.6% for male and female, respectively, (b high-school ages (11.4% and 13.6%, respectively, (c college ages (12.6% and 9.1%, respectively, (d post-college ages (11.8% and 10.0%, respectively, and (e work–family-formation ages (11.0% and 12.9%, respectively; two were nonperiod-specific groups: a permanent low-risk group for both sexes (27.3% for male, 36.4% for female, a growing-risk group for males (6.2%, and a self-limiting risk group for females (5.4%, with the likelihood increasing with age, which peaked at the age of 21 years, and then declined. Likewise, six obesity risk groups (OG were detected, of which four corresponded to the first four high-risk WG groups. The risk groups were relatively independent of race and educational attainment.Conclusions: Findings of this study imply that five risk groups for weight gain like five consecutive "tests" exist from middle-school period to work-and-family formation. Failure to pass any of these tests in the life course could lead to overweight or obese status. Further research needs to study life

  6. Developmental trajectories of respiratory sinus arrhythmia and preejection period in middle childhood.

    Science.gov (United States)

    Hinnant, J Benjamin; Elmore-Staton, Lori; El-Sheikh, Mona

    2011-01-01

    Autonomic nervous system (ANS) activity has been linked repeatedly to children's socioemotional and behavioral adaptive functioning and development, yet the literature on how various indexes of ANS activity develop in childhood is sparse. We utilized latent growth modeling to investigate the development of respiratory sinus arrhythmia (RSA), an established index of parasympathetic nervous system (PNS), and preejection period (PEP), a marker of sympathetic nervous system (SNS) influence on the heart, in children aged 8-10 years. At age 8, 251 children (128 girls, 123 boys; 162 European American, 89 African American) participated. Longitudinal data were collected during two additional waves when children were 9 and 10 years of age, with a 1-year lag between each wave. Children's RSA and PEP exhibited significant stability over time. Marginally significant variability was found among children in how RSA changed over time (slope), but there was no significant interindividual variability in PEP changes over development. A conditional growth curve model (i.e., one with predictor variables) showed that initial levels of RSA and PEP and the slope of RSA over time were predicted by several demographic factors including the child's sex and race; RSA of European American children showed significant increases over time while African American children had higher initial RSA but no significant change over time. Findings extend basic knowledge in developmental biopsychology and have implications for research focusing on ANS measures as important predictors, moderators, and mediators of childhood adaptation. © 2010 Wiley Periodicals, Inc.

  7. The typical developmental trajectory of social and executive functions in late adolescence and early adulthood.

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    Taylor, Sophie Jane; Barker, Lynne Ann; Heavey, Lisa; McHale, Sue

    2013-07-01

    Executive functions and social cognition develop through childhood into adolescence and early adulthood and are important for adaptive goal-oriented behavior (Apperly, Samson, & Humphreys, 2009; Blakemore & Choudhury, 2006). These functions are attributed to frontal networks known to undergo protracted maturation into early adulthood (Barker, Andrade, Morton, Romanowski, & Bowles, 2010; Lebel, Walker, Leemans, Phillips, & Beaulieu, 2008), although social cognition functions are also associated with widely distributed networks. Previously, nonlinear development has been reported around puberty on an emotion match-to-sample task (McGivern, Andersen, Byrd, Mutter, & Reilly, 2002) and for IQ in midadolescence (Ramsden et al., 2011). However, there are currently little data on the typical development of social and executive functions in late adolescence and early adulthood. In a cross-sectional design, 98 participants completed tests of social cognition and executive function, Wechsler Abbreviated Scale of Intelligence (Wechsler, 1999), Positive and Negative Affect Schedule (Watson, Clark, & Tellegen, 1988), Hospital Anxiety and Depression Scale (Zigmond & Snaith, 1983), and measures of pubertal development and demographics at ages 17, 18, and 19. Nonlinear age differences for letter fluency and concept formation executive functions were found, with a trough in functional ability in 18-year-olds compared with other groups. There were no age group differences on social cognition measures. Gender accounted for differences on 1 scale of concept formation, 1 dynamic social interaction scale, and 2 empathy scales. The clinical, developmental, and educational implications of these findings are discussed.

  8. Binge drinking and family history of alcoholism are associated with an altered developmental trajectory of impulsive choice across adolescence.

    Science.gov (United States)

    Jones, Scott A; Steele, Joel S; Nagel, Bonnie J

    2017-07-01

    To test whether binge drinking, the density of familial alcoholism (FHD) and their interaction are associated with an altered developmental trajectory of impulsive choice across adolescence, and whether more life-time drinks are associated with a greater change in impulsive choice across age. Alcohol-naive adolescents, with varying degrees of FHD, were recruited as part of an ongoing longitudinal study on adolescent development, and were grouped based on whether they remained non-drinkers (n = 83) or initiated binge drinking (n = 33) during follow-up. During all visits, adolescents completed a monetary delay discounting task to measure impulsive choice. The effects of binge-drinking status, FHD and their interaction on impulsive choice across adolescence were tested. Developmental Brain Imaging Laboratory, Oregon Health & Science University, Portland, Oregon, USA. A total of 116 healthy male and female adolescents (ages 10-17 years at baseline) completed two to four visits between July 2008 and May 2016. Discounting rates were obtained based on adolescents' preference for immediate or delayed rewards. FHD was based on parent-reported prevalence of alcohol use disorder in the participant's first- and second-degree relatives. Binge-drinking status was determined based on the number of recent binge-drinking episodes. There was a significant interaction effect of binge-drinking status and FHD on impulsive choice across age (b = 1.090, P alcohol-naive, greater FHD was associated with a steeper decrease in discounting rates across adolescence (b = -0.633, P alcoholism is associated with a steeper decline in impulsive choice across adolescence, but only in those who remain alcohol-naive. Meanwhile, more life-time drinks during adolescence is associated with increases in impulsive choice across age. © 2017 Society for the Study of Addiction.

  9. The developmental trajectory of brain-scalp distance from birth through childhood: implications for functional neuroimaging.

    Directory of Open Access Journals (Sweden)

    Michael S Beauchamp

    Full Text Available Measurements of human brain function in children are of increasing interest in cognitive neuroscience. Many techniques for brain mapping used in children, including functional near-infrared spectroscopy (fNIRS, electroencephalography (EEG, magnetoencephalography (MEG and transcranial magnetic stimulation (TMS, use probes placed on or near the scalp. The distance between the scalp and the brain is a key variable for these techniques because optical, electrical and magnetic signals are attenuated by distance. However, little is known about how scalp-brain distance differs between different cortical regions in children or how it changes with development. We investigated scalp-brain distance in 71 children, from newborn to age 12 years, using structural T1-weighted MRI scans of the whole head. Three-dimensional reconstructions were created from the scalp surface to allow for accurate calculation of brain-scalp distance. Nine brain landmarks in different cortical regions were manually selected in each subject based on the published fNIRS literature. Significant effects were found for age, cortical region and hemisphere. Brain-scalp distances were lowest in young children, and increased with age to up to double the newborn distance. There were also dramatic differences between brain regions, with up to 50% differences between landmarks. In frontal and temporal regions, scalp-brain distances were significantly greater in the right hemisphere than in the left hemisphere. The largest contributors to developmental changes in brain-scalp distance were increases in the corticospinal fluid (CSF and inner table of the cranium. These results have important implications for functional imaging studies of children: age and brain-region related differences in fNIRS signals could be due to the confounding factor of brain-scalp distance and not true differences in brain activity.

  10. Dyadic variability in mother-adolescent interactions: developmental trajectories and associations with psychosocial functioning.

    Science.gov (United States)

    Van der Giessen, Daniёlle; Branje, Susan J T; Frijns, Tom; Meeus, Wim H J

    2013-01-01

    Dyadic variability is considered to be a key mechanism in the development of mother-adolescent relationships, and low levels of dyadic flexibility are thought to be associated with behavior and relationship problems. The present observational study examined heterogeneity in the development of dyadic variability in mother-adolescent interactions and associations with psychosocial functioning. Dyadic variability refers to the range of emotional states during interactions of mother-adolescent dyads. During five annual home visits, 92 mother-adolescent dyads (M age T1 = 13; 65.2 % boys) were videotaped while discussing a conflict, and they completed several questionnaires on adolescents' aggressive behavior and adolescents' and mothers' perceived relationship quality. Two types of dyads were distinguished: low variability dyads (52 %) and high decreasing variability dyads (48 %). Over time, high decreasing variability dyads were characterized by a broader emotional repertoire than low variability dyads. Moreover, these two dyad types had distinct developmental patterns of psychosocial adjustment. Over time, high decreasing variability dyads showed lower levels of adolescents' aggressive behavior, and higher levels of perceived relationship quality than low variability dyads. These findings suggest that over time more dyadic variability is associated with less adjustment problems and a more constructive development of the mother-adolescent relationship. Adaptive interactions seem to be characterized by a wider range of emotional states and mothers should guide adolescents during interactions to express both positive and negative affect. Observing the dyadic variability during mother-adolescent interactions can help clinicians to distinguish adaptive from maladaptive mother-adolescent dyads.

  11. Evaluating the developmental trajectory of the episodic buffer component of working memory and its relation to word recognition in children.

    Science.gov (United States)

    Wang, Shinmin; Allen, Richard J; Lee, Jun Ren; Hsieh, Chia-En

    2015-05-01

    The creation of temporary bound representation of information from different sources is one of the key abilities attributed to the episodic buffer component of working memory. Whereas the role of working memory in word learning has received substantial attention, very little is known about the link between the development of word recognition skills and the ability to bind information in the episodic buffer of working memory and how it may develop with age. This study examined the performance of Grade 2 children (8 years old), Grade 3 children (9 years old), and young adults on a task designed to measure their ability to bind visual and auditory-verbal information in working memory. Children's performance on this task significantly correlated with their word recognition skills even when chronological age, memory for individual elements, and other possible reading-related factors were taken into account. In addition, clear developmental trajectories were observed, with improvements in the ability to hold temporary bound information in working memory between Grades 2 and 3, and between the child and adult groups, that were independent from memory for the individual elements. These findings suggest that the capacity to temporarily bind novel auditory-verbal information to visual form in working memory is linked to the development of word recognition in children and improves with age. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Genetic influences on alcohol use behaviors have diverging developmental trajectories: a prospective study among male and female twins.

    Science.gov (United States)

    Meyers, Jacquelyn L; Salvatore, Jessica E; Vuoksimaa, Eero; Korhonen, Tellervo; Pulkkinen, Lea; Rose, Richard J; Kaprio, Jaakko; Dick, Danielle M

    2014-11-01

    Both alcohol-specific genetic factors and genetic factors related to externalizing behavior influence problematic alcohol use. Little is known, however, about the etiologic role of these 2 components of genetic risk on alcohol-related behaviors across development. Prior studies conducted in a male cohort of twins suggest that externalizing genetic factors are important for predicting heavy alcohol use in adolescence, whereas alcohol-specific genetic factors increase in importance during the transition to adulthood. In this report, we studied twin brothers and sisters and brother-sister twin pairs to examine such developmental trajectories and investigate whether sex and cotwin sex effects modify these genetic influences. We used prospective, longitudinal twin data collected between ages 12 and 22 within the population-based FinnTwin12 cohort study (analytic n = 1,864). Our dependent measures of alcohol use behaviors included alcohol initiation (age 12), intoxication frequency (ages 14 and 17), and alcohol dependence criteria (age 22). Each individual's genetic risk of alcohol use disorders (AUD-GR) was indexed by his/her parents' and cotwin's DSM-IV Alcohol Dependence (AD) criterion counts. Likewise, each individual's genetic risk of externalizing disorders (EXT-GR) was indexed with a composite measure of parents' and cotwin's DSM-IV Conduct Disorder and Antisocial Personality Disorder criterion counts. EXT-GR was most strongly related to alcohol use behaviors during adolescence, while AUD-GR was most strongly related to alcohol problems in young adulthood. Further, sex of the twin and sex of the cotwin significantly moderated the associations between genetic risk and alcohol use behaviors across development: AUD-GR influenced early adolescent alcohol use behaviors in females more than in males, and EXT-GR influenced age 22 AD more in males than in females. In addition, the associations of AUD-GR and EXT-GR with intoxication frequency were greater among 14- and

  13. Comparison of Motor Skills in Children with Developmental Coordination Disorder and Normal Peers

    Directory of Open Access Journals (Sweden)

    Sahel Hemmati

    2008-09-01

    Full Text Available Objectives: Developmental Coordination Disorder (DCD is a motor skill disorder which impacts upon a child, s ability to perform age-appropriate activity of daily living and academic performance. They have problems in gross & fine motors, their upper limb coordination are impaired, too. In this way, we decided to compare motors skills with BOTMP test in children with DCD and their normal peers. Methods: In this study 30 children with DCD (age range is 6/5-8/5 have studied and compared with their normal peers. Bruininks-Oseretsky Test of Motor Proficiency (BOTMP was used. Results: The study showed Motor skills in DCD children are significantly poorer than their normal peers. (P<0/001 Gross motor, Fine motor skills and the upper limb coordination are significant impaired in DCD children. Discussion: In the process of evaluation Children with DCD, standard instrument, like BOTMP can be used.BOTMP detected deficiency in gross & fine motor and other area like, upper limb coordination. We need accurate in formations for better treatment. BOTMP can be used in the process of evaluation for every DCD child, after that goals of treatment will be clearer.

  14. Physical fitness in children with probable developmental coordination disorder and normal body mass index

    Directory of Open Access Journals (Sweden)

    Cynthia Yukiko Hiraga

    2014-01-01

    Full Text Available DOI: http://dx.doi.org/10.5007/1980-0037.2014v16n2p182   Changes in body mass index (BMI due to various factors, such as a low level of physical activity, are often associated with poor physical fitness in children with prob-able developmental coordination disorder (pDCD. This study examined whether children with pDCD would show poorer performance in terms of physical fitness when compared with their typically developing (TD peers. Thirty two children with pDCD and normal BMI and other 32 children with TD and normal BMI, matched by gender, age and BMI, performed the sit and reach, standing long jump, curl-up, modified pull-up and 9-min run tests. The children in the pDCD group showed lower explosive power, muscle strength and endurance, and cardiorespiratory fitness than children in the TD group. Overall, children with pDCD had lower levels of physical fitness, even with normal BMI.

  15. Developmental characteristics of temporal sharp transients in the EEG of normal preterm and term newborns

    Directory of Open Access Journals (Sweden)

    Nunes Magda Lahorgue

    2003-01-01

    Full Text Available OBJECTIVE: To describe developmental characteristics, morphological aspects and incidence of temporal sharp transients (TST in normal preterm and term newborns at matched conceptional ages (CA. METHOD: Neonatal EEGs from two groups of normal newborns were evaluated in order to identify and characterize TST. Group I (n=40 consisted of newborns from 34 to 40 weeks of gestational age (GA that were submitted to a single EEG between 24 and 48 hours of life. Group II consisted of 10 preterm newborns with GA between 30-32 weeks, followed with a weekly EEG until they reached term. Morphology of TST was divided in 3 groups (temporal sawtooth, isolated transients or repetitive transients. TST index, density and total number were calculated in each polysomnography and related to sleep stages and CA. Laterality (right/left was also evaluated. The groups were compared at 34, 36, 38 and 40 weeks of CA. RESULTS: TST index and density decreased with the increase of CA in both groups (p<0.0001. The temporal sawtooth feature was registered in both groups only at 34 weeks. Although rare, repetitive and isolated TST were the most prevalent morphology between 36 - 40 weeks CA. Significant intragroup difference was observed in the comparison of TST density in REM and transitional sleep in GI. Moreover, isolated TST morphology was significant higher in GI at 34 weeks when compared to the others CA. No intragroup differences were observed on GII. No significant differences between the groups were observed considering TST number, index, density, morphology or laterality, at the matched CA. CONCLUSION: TST are normal features of neonatal EEG, as they are registered in normal newborns. Its incidence varies accordingly to morphology and they tend to disappear following the increase of CA. Temporal sawtooth appears more often in preterm newborns. Our results suggest that TST index, density and morphology variability may be a function of CA.

  16. Developmental trajectories and longitudinal mediation effects of self-esteem, peer attachment, child maltreatment and depression on early adolescents.

    Science.gov (United States)

    Ju, Soyoung; Lee, Yanghee

    2018-02-01

    The purpose of this study is to identify the developmental trajectories of peer attachment, self-esteem, depression, and child maltreatment, and to understand the longitudinal mediation effects that peer attachment and self-esteem have on the influence of perceived abuse on early adolescent depression. This study uses Year 1 to Year 5 data of the 4th grader panel of the Korea Youth Panel Survey (KYPS) and utilizes a multivariate latent growth model to analyze the main variables in the applicable data between 5th (i.e., Year 2) and 8th (i.e., Year 5) grades. The results indicate that from the 5th to the 8th grade, the degree of abuse and depression increases while self-esteem gradually decreases with slowly lowering peer attachment. A significant distribution of the initial values and the rate of change were present for all main variables of the study, confirming individual differences in time wise changes. Further, more exposure to abuse correlated with a decrease in self-esteem, while an increase in self-esteem greatly reduced depression. The initial value of self-esteem showed a partial mediation effect, whereas the rate of change indicated a full mediation effect with a significant longitudinal mediation effect. More experience of abuse during early adolescence indicated a lower degree of peer attachment, and a higher peer attachment was related to decreased depression. A significant partial mediation effect was present for both the initial value and the rate of change of peer attachment, and a longitudinal mediation effect was present. This study confirmed that self-esteem in early adolescents is an important protective factor that can greatly reduce the degree of depression, and suggests continuous interventions conducted to increase self-esteem in adolescence. Furthermore, by determining that peer attachment decreases the degree of depression in children at risk, the study emphasizes the healing aspect of adolescent peer attachment. Copyright © 2017 Elsevier

  17. Identifying developmental trajectories of body mass index in childhood using latent class growth (mixture modelling: associations with dietary, sedentary and physical activity behaviors: a longitudinal study

    Directory of Open Access Journals (Sweden)

    Maaike Koning

    2016-10-01

    Full Text Available Abstract Background To date, many epidemiologic studies examining associations between obesity and dietary and sedentary/physical activity behaviors have focused on assessing Body Mass Index (BMI at one point in time. Recent developments in statistical techniques make it possible to study the potential heterogeneity in the development of BMI during childhood by identifying distinct subpopulations characterized by distinct developmental trajectories. Using Latent Class Growth (Mixture Modelling (LCGMM techniques we aimed to identify BMI trajectories in childhood and to examine associations between these distinct trajectories and dietary, sedentary and physical activity behaviors. Methods This longitudinal study explored BMI standard deviation score (SDS trajectories in a sample of 613 children from 4 to 12 years of age. In 2006, 2009 and 2012 information on children’s health related behaviors was obtained by parental questionnaires, and children’s height and weight were measured. Associations with behaviors were investigated with logistic regression models. Results We identified two BMI SDS trajectories; a decreasing BMI SDS trajectory (n = 416; 68 % and an increasing BMI SDS trajectory (n = 197; 32 %. The increasing BMI SDS trajectory consisted of more participants of lower socio-economic status (SES and of non-western ethnicity. Maternal overweight status was associated with being in the increasing BMI SDS trajectory at both baseline and follow-up six years later (2006: Odds Ratio (OR, 2.9; 95 % confidence interval (CI 1.9 to 4.3; 2012 OR, 1.8; 95 % CI 1.2 to 2.6. The increasing BMI SDS trajectory was associated with the following behaviors; drinking sugared drinks > 3 glasses per day, participation in organized sports  2 h per day, though participation in organized sports at follow-up was the only significant result. Conclusions Our results indicate the importance of healthy lifestyle behaviors at a young age, and

  18. A Developmental Study of Static Postural Control and Superimposed Arm Movements in Normal and Slowly Developing Children.

    Science.gov (United States)

    Fisher, Janet M.

    Selected electromyographic parameters underlying static postural control in 4, 6, and 8 year old normally and slowly developing children during performance of selected arm movements were studied. Developmental delays in balance control were assessed by the Cashin Test of Motor Development (1974) and/or the Williams Gross Motor Coordination Test…

  19. Trajectories of Diurnal Cortisol in Mothers of Children with Autism and Other Developmental Disabilities: Relations to Health and Mental Health

    Science.gov (United States)

    Dykens, Elisabeth M.; Lambert, Warren

    2013-01-01

    This study used a stress biomarker, diurnal cortisol, to identify how elevated stress in mothers of children and adults with autism and other disabilities relates to their health and mental health. Based on semi-parametric, group-based trajectory analysis of 91 mothers, two distinctive cortisol trajectories emerged: blunted (63%) or steep (37%).…

  20. Developmental trajectories of fronto-executive functions in 22q11.2 deletion syndrome: A preliminary study

    LENUS (Irish Health Repository)

    Howley, S A

    2011-01-01

    22qll.2 deletion syndrome (22qllDS) is associated with borderline-mild intellectual disability and specific neurocognitive deficits, particularly in prefrontally-mediated executive functions (EF). There is evidence for white matter abnormalities in frontal cortical regions in 22qllDS, however little is known about the development of EF across the age range. Forty-eight individuals with 22qllDS were divided into 3 age groups: Child (7 male; n = 16; 6–11 years; M (SD) age = 8.4 (1.7); mean FSIQ = 72.9); Adolescent (7 male; n = 15; 12–15 years; M (SD) age = 13.1 (0.8); mean FSIQ = 68.0) and Adult (7 male; n = 17; 16–45 years; M (SD) age = 28.8 (11.5); mean FSIQ = 69.6). Forty healthy controls were also recruited and divided into the same 3 age groups: Child (6 male; 6–11 years, n = 12; M (SD) age = 9.3 (1.7); mean FSIQ = 99.1); Adolescent (6 male; 12–15 years; n = 12; M (SD) age = 13.2 (1.1); mean FSIQ = 100.9) and Adult (6 male; 16–45 years; n = 16; M (SD) age = 28.8 (9.4); mean FSIQ = 109). All participants completed standardised tests of a range of executive functions, specifically working memory, planning, problem-solving, strategy formation, cognitive flexibility and inhibition, and cross-sectional developmental trajectories of each function were constructed. No age-mediated improvements on EF tasks were observed in the 22qllDS groups, with the exception of verbal working memory. The control group exhibited significant age-mediated improvements in working memory, strategy formation and planning efficiency. These findings support the hypothesis that 22qllDS individuals experience atypical development of neuroanatomical regions and networks associated with EF in typical individuals. Future longitudinal work is required to examine intra-individual development of executive and non-executive cognitive processes.

  1. Health-related quality of life and emotional and behavioral difficulties after extreme preterm birth: developmental trajectories

    Directory of Open Access Journals (Sweden)

    Bente Johanne Vederhus

    2015-01-01

    Full Text Available Background. Knowledge of long-term health related outcomes in contemporary populations born extremely preterm (EP is scarce. We aimed to explore developmental trajectories of health-related quality of life (HRQoL and behavior from mid-childhood to early adulthood in extremely preterm and term-born individuals.Methods. Subjects born at gestational age ≤28 weeks or with birth weight ≤1,000 g within a region of Norway in 1991–92 and matched term-born control subjects were assessed at 10 and 18 years. HRQoL was measured with the Child Health Questionnaire (CHQ and behavior with the Child Behavior Checklist (CBCL, using parent assessment at both ages and self-assessment at 18 years.Results. All eligible EP (n = 35 and control children participated at 10 years, and 31 (89% and 29 (83% at 18 years. At 10 years, the EP born boys were given significantly poorer scores by their parents than term-born controls on most CHQ and CBCL scales, but the differences were minor at 18 years; i.e., significant improvements had occurred in several CHQ (self-esteem, general health and parental impact-time and CBCL (total problem, internalizing and anxious/depressed scales. For the girls, the differences were smaller at 10 years and remained unchanged by 18 years. Emotional/behavioral difficulties at 10 years similarly predicted poorer improvement on CHQ-scales for both EP and term-born subjects at 18 years. Self-assessment of HRQoL and behavior at 18 years was similar in the EP and term-born groups on most scales.Conclusions. HRQoL and behavior improved towards adulthood for EP born boys, while the girls remained relatively similar, and early emotional and behavioral difficulties predicted poorer development in HRQoL through adolescence. These data indicate that gender and a longitudinal perspective should be considered when addressing health and wellbeing after extremely preterm birth.

  2. The trochlear pre-ossification center: a normal developmental stage and potential pitfall on MR images

    Energy Technology Data Exchange (ETDEWEB)

    Jaimes, Camilo [The Children' s Hospital of Philadelphia, Department of Radiology, Philadelphia, PA (United States); Jimenez, Mauricio [Hospital of the University of Pennsylvania, Department of Radiology, Philadelphia, PA (United States); Marin, Diana [Miami Children' s Hospital, Department of Radiology, Miami, FL (United States); Ho-Fung, Victor; Jaramillo, Diego [The Children' s Hospital of Philadelphia, Department of Radiology, Philadelphia, PA (United States); University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA (United States)

    2012-11-15

    The hypertrophic changes that occur in the cartilage of an epiphysis prior to the onset of ossification are known as the pre-ossification center. Awareness of the appearance of the pre-ossification center on MR images is important to avoid confusing normal developmental changes with pathology. The purpose of this study was to determine the characteristics of the trochlear pre-ossification center on MR imaging and examine age and gender differences. We retrospectively analyzed MR images from 61 children. The trochleas were categorized into three types on the basis of signal intensity (SI). Trochlear types were compared to age and gender. There was no significant difference between the ages of boys and girls. Type 1 trochleas showed homogeneous SI on all pulse sequences. Type 2 trochleas demonstrated a focus of high SI in the epiphyseal cartilage on fat-suppressed water-sensitive sequences, with high or intermediate SI on gradient-echo images (pre-ossification center). Type 3 trochleas showed low SI on fat-suppressed water-sensitive sequences and gradient-echo images. Thirty-seven trochleas were described as type 1, sixteen as type 2 and eight as type 3. ANOVAs confirmed a statistically significant difference in the age of children with type 3 trochleas and those with types 1 and 2 (P < 0.001). Spearman rank correlations determined a positive relationship between trochlear type and age of the children (r = 0.53). Development-related changes in the trochlea follow a predictable pattern. The signal characteristics of the pre-ossification center likely reflect normal chondrocyte hypertrophy and an increase in free water in the matrix. (orig.)

  3. Developmental switching in Physarum polycephalum : Petri net analysis of single cell trajectories of gene expression indicates responsiveness and genetic plasticity of the Waddington quasipotential landscape

    International Nuclear Information System (INIS)

    Werthmann, Britta; Marwan, Wolfgang

    2017-01-01

    The developmental switch to sporulation in Physarum polycephalum is a phytochrome-mediated far-red light-induced cell fate decision that synchronously encompasses the entire multinucleate plasmodial cell and is associated with extensive reprogramming of the transcriptome. By repeatedly taking samples of single cells after delivery of a light stimulus pulse, we analysed differential gene expression in two mutant strains and in a heterokaryon of the two strains all of which display a different propensity for making the cell fate decision. Multidimensional scaling of the gene expression data revealed individually different single cell trajectories eventually leading to sporulation. Characterization of the trajectories as walks through states of gene expression discretized by hierarchical clustering allowed the reconstruction of Petri nets that model and predict the observed behavior. Structural analyses of the Petri nets indicated stimulus- and genotype-dependence of both, single cell trajectories and of the quasipotential landscape through which these trajectories are taken. The Petri net-based approach to the analysis and decomposition of complex cellular responses and of complex mutant phenotypes may provide a scaffold for the data-driven reconstruction of causal molecular mechanisms that shape the topology of the quasipotential landscape. (paper)

  4. Developmental switching in Physarum polycephalum: Petri net analysis of single cell trajectories of gene expression indicates responsiveness and genetic plasticity of the Waddington quasipotential landscape

    Science.gov (United States)

    Werthmann, Britta; Marwan, Wolfgang

    2017-11-01

    The developmental switch to sporulation in Physarum polycephalum is a phytochrome-mediated far-red light-induced cell fate decision that synchronously encompasses the entire multinucleate plasmodial cell and is associated with extensive reprogramming of the transcriptome. By repeatedly taking samples of single cells after delivery of a light stimulus pulse, we analysed differential gene expression in two mutant strains and in a heterokaryon of the two strains all of which display a different propensity for making the cell fate decision. Multidimensional scaling of the gene expression data revealed individually different single cell trajectories eventually leading to sporulation. Characterization of the trajectories as walks through states of gene expression discretized by hierarchical clustering allowed the reconstruction of Petri nets that model and predict the observed behavior. Structural analyses of the Petri nets indicated stimulus- and genotype-dependence of both, single cell trajectories and of the quasipotential landscape through which these trajectories are taken. The Petri net-based approach to the analysis and decomposition of complex cellular responses and of complex mutant phenotypes may provide a scaffold for the data-driven reconstruction of causal molecular mechanisms that shape the topology of the quasipotential landscape.

  5. The impact of a family-centered intervention on the ecology of adolescent antisocial behavior: modeling developmental sequelae and trajectories during adolescence.

    Science.gov (United States)

    Van Ryzin, Mark J; Dishion, Thomas J

    2012-08-01

    This study used an experimental, longitudinal field trial involving random assignment to the Family Check-Up (FCU) to explore the social ecology of adolescent antisocial behavior. A sample of 998 youths and their families was followed from early to late adolescence (age 12 to 18-19). In the intervention condition, 115 families (23%) elected to receive the FCU. In general, random assignment to the FCU in middle school was associated with reductions in late adolescence antisocial behavior (age 18-19). Variable-centered analyses revealed that the effects were mediated by reductions in family conflict from early to middle adolescence (age 12-15). The link between family conflict and antisocial behavior in turn was mediated by association with deviant peers at age 17; parental monitoring at age 17 was also influential but did not attain the status of a mediator. Person-oriented analyses suggested that the FCU was associated with declining trajectories of family conflict and rising trajectories of parental monitoring but was not associated with trajectories of deviant peer association. A dual-trajectory analysis indicated that the pathways to adolescent antisocial behavior were myriad and varied, suggesting new directions for developmental and intervention research.

  6. Developmental Growth Trajectories of Self-Esteem in Adolescence: Associations with Child Neglect and Drug Use and Abuse in Young Adulthood.

    Science.gov (United States)

    Oshri, Assaf; Carlson, Matthew W; Kwon, Josephine A; Zeichner, Amos; Wickrama, Kandauda K A S

    2017-01-01

    Neglectful rearing is linked with young adults' substance use and abuse, though the developmental mechanisms that underlie this association are unclear. The present study examines links between self-esteem growth during adolescence, childhood supervisory versus physical neglect severity, and substance use and abuse in young adulthood. A sample of youth was obtained from the Add Health study (N = 8738; 55.4 %-Female; 20 %-African American, 14.7 %-Hispanic). Growth mixture modeling analyses supported declining, ascending, and stable high self-esteem trajectories. The declining and ascending trajectories reported greater neglect and alcohol abuse (but not use) as well as cannabis use and abuse. The findings suggest that compromised development of self-esteem underlies associations between neglect and substance use and abuse. Preventive interventions may benefit from targeting self-esteem among neglected youth.

  7. Early developmental trajectories of number knowledge and math achievement from 4 to 10 years: Low-persistent profile and early-life predictors.

    Science.gov (United States)

    Garon-Carrier, Gabrielle; Boivin, Michel; Lemelin, Jean-Pascal; Kovas, Yulia; Parent, Sophie; Séguin, Jean R; Vitaro, Frank; Tremblay, Richard E; Dionne, Ginette

    2018-06-01

    Little is known about the development of number knowledge (NK) and the antecedents of low-persistent NK profiles in early childhood. We documented the developmental trajectories of NK across the transition from preschool to elementary school, their predictive validity with respect to later math achievement, and the child and family early-life factors associated with low NK profiles. Children's NK was assessed four times at regular intervals between the ages 4 and 7 years in a large, representative population-based sample. Developmental trajectories of NK were established for 1597 children. These children were also assessed with respect to several features of their family environment at 5, 17, and 29 months, as well as their cognitive skills at age 41 months. Analyses revealed a best-fitting 4-trajectory model, characterized by Low-Increasing (10% of the children), Moderate-Increasing (39%), Moderate-Fast Increasing (32%) and High-Increasing (19%) groups. Children of these trajectory groups differed significantly with respect to math achievement at ages 8 and 10 years, with the Low-Increasing group persistently scoring lower than the other groups throughout these years. Children of Low-Increasing NK group were from household of lower income and father with low educational background, poorer early cognitive development, and more importantly, reduced visual-spatial skills and memory-span. Children displaying reduced cognitive abilities and impoverished living conditions early in life are at greater risk of low NK throughout late preschool and school entry, with ensuing difficulties in math achievement. They deserve early preventive attention to help alleviate later mathematic difficulties. Copyright © 2018 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.

  8. Drosophila larvae synthesize the putative oncometabolite L-2-hydroxyglutarate during normal developmental growth.

    Science.gov (United States)

    Li, Hongde; Chawla, Geetanjali; Hurlburt, Alexander J; Sterrett, Maria C; Zaslaver, Olga; Cox, James; Karty, Jonathan A; Rosebrock, Adam P; Caudy, Amy A; Tennessen, Jason M

    2017-02-07

    L-2-hydroxyglutarate (L-2HG) has emerged as a putative oncometabolite that is capable of inhibiting enzymes involved in metabolism, chromatin modification, and cell differentiation. However, despite the ability of L-2HG to interfere with a broad range of cellular processes, this molecule is often characterized as a metabolic waste product. Here, we demonstrate that Drosophila larvae use the metabolic conditions established by aerobic glycolysis to both synthesize and accumulate high concentrations of L-2HG during normal developmental growth. A majority of the larval L-2HG pool is derived from glucose and dependent on the Drosophila estrogen-related receptor (dERR), which promotes L-2HG synthesis by up-regulating expression of the Drosophila homolog of lactate dehydrogenase (dLdh). We also show that dLDH is both necessary and sufficient for directly synthesizing L-2HG and the Drosophila homolog of L-2-hydroxyglutarate dehydrogenase (dL2HGDH), which encodes the enzyme that breaks down L-2HG, is required for stage-specific degradation of the L-2HG pool. In addition, dLDH also indirectly promotes L-2HG accumulation via synthesis of lactate, which activates a metabolic feed-forward mechanism that inhibits dL2HGDH activity and stabilizes L-2HG levels. Finally, we use a genetic approach to demonstrate that dLDH and L-2HG influence position effect variegation and DNA methylation, suggesting that this compound serves to coordinate glycolytic flux with epigenetic modifications. Overall, our studies demonstrate that growing animal tissues synthesize L-2HG in a controlled manner, reveal a mechanism that coordinates glucose catabolism with L-2HG synthesis, and establish the fly as a unique model system for studying the endogenous functions of L-2HG during cell growth and proliferation.

  9. Drosophila larvae synthesize the putative oncometabolite L-2-hydroxyglutarate during normal developmental growth

    Science.gov (United States)

    Li, Hongde; Chawla, Geetanjali; Hurlburt, Alexander J.; Sterrett, Maria C.; Zaslaver, Olga; Cox, James; Karty, Jonathan A.; Rosebrock, Adam P.; Caudy, Amy A.

    2017-01-01

    L-2-hydroxyglutarate (L-2HG) has emerged as a putative oncometabolite that is capable of inhibiting enzymes involved in metabolism, chromatin modification, and cell differentiation. However, despite the ability of L-2HG to interfere with a broad range of cellular processes, this molecule is often characterized as a metabolic waste product. Here, we demonstrate that Drosophila larvae use the metabolic conditions established by aerobic glycolysis to both synthesize and accumulate high concentrations of L-2HG during normal developmental growth. A majority of the larval L-2HG pool is derived from glucose and dependent on the Drosophila estrogen-related receptor (dERR), which promotes L-2HG synthesis by up-regulating expression of the Drosophila homolog of lactate dehydrogenase (dLdh). We also show that dLDH is both necessary and sufficient for directly synthesizing L-2HG and the Drosophila homolog of L-2-hydroxyglutarate dehydrogenase (dL2HGDH), which encodes the enzyme that breaks down L-2HG, is required for stage-specific degradation of the L-2HG pool. In addition, dLDH also indirectly promotes L-2HG accumulation via synthesis of lactate, which activates a metabolic feed-forward mechanism that inhibits dL2HGDH activity and stabilizes L-2HG levels. Finally, we use a genetic approach to demonstrate that dLDH and L-2HG influence position effect variegation and DNA methylation, suggesting that this compound serves to coordinate glycolytic flux with epigenetic modifications. Overall, our studies demonstrate that growing animal tissues synthesize L-2HG in a controlled manner, reveal a mechanism that coordinates glucose catabolism with L-2HG synthesis, and establish the fly as a unique model system for studying the endogenous functions of L-2HG during cell growth and proliferation. PMID:28115720

  10. Developmental trajectories of attention and executive functioning in infants born preterm: The influence of perinatal risk factors and maternal interactive styles

    NARCIS (Netherlands)

    van de Weijer-Bergsma, E.

    2009-01-01

    Infants born preterm (born before 37 weeks of gestation) are at a heightened risk for developmental delay and learning disabilities. Even children born preterm who have intellectual abilities within the normal range at school age often require special educational services. The preterm population is

  11. Group-based developmental BMI trajectories, polycystic ovary syndrome, and gestational diabetes: a community-based longitudinal study.

    Science.gov (United States)

    Kakoly, Nadira Sultana; Earnest, Arul; Moran, Lisa J; Teede, Helena J; Joham, Anju E

    2017-11-06

    Obesity is common in young women, increasing insulin resistance (IR) and worsening pregnancy complications, including gestational diabetes (GDM). Women with polycystic ovary syndrome (PCOS) are commonly obese, which aggravates the severity of PCOS clinical expression. Relationships between these common insulin-resistant conditions, however, remain unclear. We conducted a secondary analysis of the Australian Longitudinal Study on Women's Health (ALSWH) database, including data from 8009 women aged 18-36 years across six surveys. We used latent-curve growth modelling to identify distinct body mass index (BMI) trajectories and multinomial logistic regression to explore sociodemographic and health variables characterizing BMI group membership. Logistic regression was used to assess independent risk of GDM. A total of 662 women (8.29%, 95% CI 7.68-8.89) reported PCOS. Three distinct BMI trajectories emerged, namely low stable (LSG) (63.8%), defined as an average trajectory remaining at ~25 kg/m 2 ; moderately rising (MRG) (28.8%), a curvilinear trajectory commencing in a healthy BMI and terminating in the overweight range; and high-rising (HRG) (7.4%), a curvilinear trajectory starting and terminating in the obese range. A high BMI in early reproductive life predicted membership in higher trajectories. The HRG BMI trajectory was independently associated with GDM (OR 2.50, 95% CI 1.80-3.48) and was a stronger correlate than PCOS (OR 1.89, 95% CI 1.41-2.54), maternal age, socioeconomic status, or parity. Our results suggest heterogeneity in BMI change among Australian women of reproductive age, with and without PCOS. Reducing early adult life weight represents an ideal opportunity to intervene at an early stage of reproductive life and decreases the risk of long-term metabolic complications such as GDM.

  12. Developmental progression to early adult binge drinking and marijuana use from worsening versus stable trajectories of adolescent attention deficit/hyperactivity disorder and delinquency.

    Science.gov (United States)

    Howard, Andrea L; Molina, Brooke S G; Swanson, James M; Hinshaw, Stephen P; Belendiuk, Katherine A; Harty, Seth C; Arnold, L Eugene; Abikoff, Howard B; Hechtman, Lily; Stehli, Annamarie; Greenhill, Laurence L; Newcorn, Jeffrey H; Wigal, Timothy

    2015-05-01

    To examine the association between developmental trajectories of inattention, hyperactivity-impulsivity and delinquency through childhood and adolescence (ages 8-16 years) and subsequent binge drinking and marijuana use in early adulthood (age 21 years). Prospective naturalistic follow-up of children with attention deficit/hyperactivity disorder (ADHD) previously enrolled in a randomized controlled trial (RCT). Treatment-phase assessments occurred at 3, 9 and 14 months after randomization; follow-up assessments occurred at 24 months, 36 months, and 6, 8 and 12 years after randomization. Secondary analysis of data from the Multimodal Treatment Study of ADHD (MTA), a multi-site RCT comparing the effects of careful medication management, intensive behavior therapy, their combination, and referral to usual community care. A total of 579 children with DSM-IV ADHD combined type, aged 7.0 and 9.9 years at baseline (mean = 8.5, SD = 0.80). Ratings of inattention, hyperactivity-impulsivity and delinquency were collected from multiple informants at baseline and through the 8-year follow-up. Self-reports of binge drinking and marijuana use were collected at the 12-year follow-up (mean age 21 years). Trajectories of worsening inattention symptoms and delinquency (and less apparent improvement in hyperactivity-impulsivity) were associated with higher rates of early adult binge drinking and marijuana use, compared with trajectories of stable or improving symptoms and delinquency (of 24 comparisons, all P-values delinquency during adolescence are were associated with higher levels of early adult substance use; this pattern may reflect a developmental course of vulnerability to elevated substance use in early adulthood. © 2015 Society for the Study of Addiction.

  13. Comparison in stress of caring mothers of children with developmental, external and internal disorders and normal children

    Directory of Open Access Journals (Sweden)

    Narges Zamani

    2017-06-01

    Full Text Available However, having a baby brings positive emotions such as happiness, sense of maturity and proud, parenting's issue could cause high level of stress and child's characteristics was a detrimental factor which can effect on parent's stress, so the aim of this research was comparison of stress of caring in mothers of children with developmental, external, and internal disorders and normal children. The study population included all mothers of children with developmental, emotional, and disruptive behavior disorders, and mothers with normal children in Hamadan (a city in Iran. 240 mothers (4 groups include 60 mothers were chosen based on simple random sampling. Family inventory of life events and changes Mc Cubbin, Patterson & Wilson was used for assessing participants. The results showed that maternal stress in mothers with children who have diagnosis of disruptive behavior disorders were significantly more than of mothers of children with developmental disorders, emotional and mothers of normal children. The present study showed that disruptive behavior disorders in children have a greater impact on their mothers. So, we suggest approved psychological interventions for helping mothers of children with psychological problems, particularly children with external disorders.

  14. Developmental Trajectories of African American Adolescents' Family Conflict: Differences in Mental Health Problems in Young Adulthood

    Science.gov (United States)

    Choe, Daniel Ewon; Stoddard, Sarah A.; Zimmerman, Marc A.

    2014-01-01

    Family conflict is a salient risk factor for African American adolescents' mental health problems. No study we are aware of has estimated trajectories of their family conflict and whether groups differ in internalizing and externalizing problems during the transition to young adulthood, a critical antecedent in adult mental health and…

  15. Developmental Trajectories of the Orbitofrontal Cortex and Anhedonia in Middle Childhood and Risk for Substance Use in Adolescence in a Longitudinal Sample of Depressed and Healthy Preschoolers.

    Science.gov (United States)

    Luby, Joan L; Agrawal, Arpana; Belden, Andy; Whalen, Diana; Tillman, Rebecca; Barch, Deanna M

    2018-03-21

    Deficits in reward processing are established in mood and substance use disorders and are known risk factors for these disorders. Volume reductions of the orbitofrontal cortex and the striatum, regions that subserve neural response to reward, have been shown to be related to anhedonia in depressive and substance use disorders. The authors sought to investigate how structural maturation of these regions in childhood varies with level of anhedonia and predicts later substance use. The study employed data from a sample of depressed and healthy preschoolers studied longitudinally that included three waves of neuroimaging from school age to adolescence. Three years after scan 3, at ages 13-18, participants underwent a comprehensive behavioral and substance use assessment. Multilevel modeling was used to investigate the relationship between anhedonia and the growth trajectories of the striatum and orbitofrontal cortex. Zero-inflated Poisson regression models were then used to determine whether the intercepts and slopes of these trajectories predicted later alcohol and marijuana use frequency in adolescence. The anhedonia-by-age interaction was significant in the multilevel modeling of orbitofrontal cortical but not striatal volume. Higher anhedonia ratings were significantly associated with steeper decline in orbitofrontal cortical volume with age. Orbitofrontal cortical volume and thickness at age 12 and trajectory over time significantly and negatively predicted subsequent alcohol and marijuana use frequency but not depression during adolescence. The findings suggest that the development of the orbitofrontal cortex during childhood is strongly linked to experiences of anhedonia and that these growth trajectories predict substance use during a developmentally critical period.

  16. Pilot study on quantitative assessment of muscle imbalance: differences of muscle synergies, equilibrium-point trajectories, and endpoint stiffness in normal and pathological upper-limb movements.

    Science.gov (United States)

    Oku, Takanori; Uno, Kanna; Nishi, Tomoki; Kageyama, Masayuki; Phatiwuttipat, Pipatthana; Koba, Keitaro; Yamashita, Yuto; Murakami, Kenta; Uemura, Mitsunori; Hirai, Hiroaki; Miyazaki, Fumio; Naritomi, Hiroaki

    2014-01-01

    This paper proposes a novel method for assessment of muscle imbalance based on muscle synergy hypothesis and equilibrium point (EP) hypothesis of motor control. We explain in detail the method for extracting muscle synergies under the concept of agonist-antagonist (AA) muscle pairs and for estimating EP trajectories and endpoint stiffness of human upper limbs in a horizontal plane using an electromyogram. The results of applying this method to the reaching movement of one normal subject and one hemiplegic subject suggest that (1) muscle synergies (the balance among coactivation of AA muscle pairs), particularly the synergies that contributes to the angular directional kinematics of EP and the limb stiffness, are quite different between the normal subject and the hemiplegic subject; (2) the concomitant EP trajectory is also different between the normal and hemiplegic subjects, corresponding to the difference of muscle synergies; and (3) the endpoint (hand) stiffness ellipse of the hemiplegic subject becomes more elongated and orientation of the major axis rotates clockwise more than that of the normal subject. The level of motor impairment would be expected to be assessed from a comparison of these differences of muscle synergies, EP trajectories, and endpoint stiffness among normal and pathological subjects using the method.

  17. Developmental Trajectories of DSM-IV Symptoms of Attention-Deficit/Hyperactivity Disorder: Genetic Effects, Family Risk and Associated Psychopathology

    Science.gov (United States)

    Larsson, Henrik; Dilshad, Rezin; Lichtenstein, Paul; Barker, Edward D.

    2011-01-01

    Background: DSM-IV specifies three ADHD subtypes; the combined, the hyperactive-impulsive and the inattentive. Little is known about the developmental relationships underlying these subtypes. The objective of this study was to describe the development of parent-reported hyperactivity-impulsivity and inattention symptoms from childhood to…

  18. Differing Developmental Trajectories in Heart Rate Responses to Speech Stimuli in Infants at High and Low Risk for Autism Spectrum Disorder.

    Science.gov (United States)

    Perdue, Katherine L; Edwards, Laura A; Tager-Flusberg, Helen; Nelson, Charles A

    2017-08-01

    We investigated heart rate (HR) in infants at 3, 6, 9, and 12 months of age, at high (HRA) and low (LRC) familial risk for ASD, to identify potential endophenotypes of ASD risk related to attentional responses. HR was extracted from functional near-infrared spectroscopy recordings while infants listened to speech stimuli. Longitudinal analysis revealed that HRA infants and males generally had lower baseline HR than LRC infants and females. HRA infants showed decreased HR responses to early trials over development, while LRC infants showed increased responses. These findings suggest altered developmental trajectories in physiological responses to speech stimuli over the first year of life, with HRA infants showing less social orienting over time.

  19. Developmental Trajectories of Marijuana Use among Men: Examining Linkages with Criminal Behavior and Psychopathic Features into the Mid-30s

    Science.gov (United States)

    Pardini, Dustin; Bechtold, Jordan; Loeber, Rolf; White, Helene

    2015-01-01

    Objectives Examine whether young men who chronically use marijuana are at risk for engaging in drug-related and non-drug-related criminal offending and exhibiting psychopathic personality features in their mid-30s. Methods Patterns of marijuana use were delineated in a sample of predominately Black and White young men from adolescence to the mid-20s using latent class growth curve analysis. Self-report and official records of criminal offending and psychopathic personality features were assessed in the mid-30s. Analyses controlled for multiple factors indicative of a preexisting antisocial lifestyle and co-occurring use of other substances and tested for moderation by race. Results Four latent marijuana trajectory groups were identified: chronic high, adolescence-limited, late increasing, and low/nonusers. Relative to low/nonusers, chronic high and late increasing marijuana users exhibited more adult psychopathic features and were more likely to engage in drug-related offending during their mid-30s. Adolescence-limited users were similar to low/nonusers in terms of psychopathic features but were more likely to be arrested for drug-related crimes. No trajectory group differences were found for violence or theft, and the group differences were not moderated by race. Conclusions Young men who engage in chronic marijuana use from adolescence into their 20s are at increased risk for exhibiting psychopathic features, dealing drugs, and enduring drug-related legal problems in their mid-30s relative to men who remain abstinent or use infrequently. PMID:26568641

  20. Microstructural callosal abnormalities in normal-appearing brain of children with developmental delay detected with diffusion tensor imaging

    International Nuclear Information System (INIS)

    Ding, Xiao-Qi; Sun, Yimeng; Illies, Till; Zeumer, Hermann; Fiehler, Jens; Kruse, Bernd; Lanfermann, Heinrich

    2009-01-01

    Callosal fibres play an important role in psychomotor and cognitive functions. The purpose of this study was to investigate possible microstructural abnormalities of the corpus callosum in children with developmental delay, who have normal conventional brain MR imaging results. Seventeen pediatric patients (aged 1-9 years) with developmental delay were studied. Quantitative T2 and fractional anisotropy (FA) values were measured at the genu and splenium of the corpus callosum (CC). Fibre tracking, volumetric determination, as well as fibre density calculations of the CC were also carried out. The results were compared with those of the age-matched healthy subjects. A general elevation of T2 relaxation times (105 ms in patients vs. 95 ms in controls) and reduction of the FA values (0.66 in patients vs. 0.74 in controls) at the genu of the CC were found in patients. Reductions of the fibre numbers (5,464 in patients vs. 8,886 in controls) and volumes (3,415 ml in patients vs. 5,235 ml in controls) of the CC were found only in patients older than 5 years. The study indicates that despite their inconspicuous findings in conventional MRI microstructural brain abnormalities are evident in these pediatric patients suffering from developmental delay. (orig.)

  1. Developmental trajectories of infants and toddlers with good initial presentation following moderate or severe traumatic brain injury: a pilot clinical assessment project.

    Science.gov (United States)

    Pomerleau, Geneviève; Hurteau, Anne-Marie; Parent, Line; Doucet, Katrine; Corbin-Berrigan, Laurie-Ann; Gagnon, Isabelle

    2012-01-01

    The purpose of this study was to review the feasibility and usefulness of instituting a clinical protocol of scheduled assessments for children after a moderate or severe traumatic brain injury (TBI) sustained before the age of 2 years and showing no immediate deficits at hospital discharge, as well as to explore the early developmental trajectories of these children. Exploratory analytical cohort study. Pediatric Trauma Center Out-patient services. 31 children were followed within the clinical protocol of scheduled assessments. The protocol included an immediate post-injury clinical assessment of infants who sustained a TBI and follow-up assessments at the ages of 9 months, 18 months (if injured prior to that age), 30 months, and 42 months. Domains assessed at each scheduled visit included hearing, speech and language, motor performance, personal social abilities, and adaptive behaviors. Clinicians reported few difficulties with scheduling or administering the assessments, maintaining a 67% participation rate at the end of the follow-up period, thus demonstrating the feasibility of the protocol in this population. Scores on the majority of formal tests showed high variability and 15-20% of children presented with clinically significant motor and/or language delays. By 42 months of age, difficulties with adaptive behavior and personal social abilities were identified in our sample of children when compared to published norms. Qualitative clinical findings from professionals identified between 25-50% of children with potential attentional difficulties throughout the follow-up period. Findings from this study demonstrate the feasibility of implementing a clinical protocol of assessment for infants and toddlers who sustain a TBI before the age of 2 years and present with no impairments at the time of discharge from hospital. Developmental problems in this population appear to be easier to identify later in the toddler years as opposed to immediately following the TBI

  2. NEUROLOGICAL DEVELOPMENT DURING TODDLING AGE IN NORMAL-CHILDREN AND CHILDREN AT RISK OF DEVELOPMENTAL DISORDERS

    NARCIS (Netherlands)

    HEMPEL, MS

    Toddling age (1.5-4 years) is a period in which the quality rather than the quantity of motor functions changes. We examined 305 normal and 43 so called 'risk' children with an examination technique which concentrates on observations of motor functions (grasping, sitting, crawling, standing and

  3. Divergent Developmental Trajectories and Strategic Coupling in the Pearl River Delta: Where Is a Sustainable Way of Regional Economic Growth?

    Directory of Open Access Journals (Sweden)

    Yi Liu

    2017-10-01

    Full Text Available This paper interprets regional economic sustainability in the context of the globalization of late-coming regions. Drawing upon the concept of strategic coupling from economic geography, this paper proposes two types of strategic coupling, captive and proactive coupling, for better understanding regional sustainability and resilience through the experiences of the Pearl River Delta in China. It finds that sub-regional economies under captive coupling become highly dependent on exogenous growth and are vulnerable to external shocks. This trajectory looks less sustainable according to the general understanding, but it interestingly shows better resilience during and after the 2008 global financial crisis. In contrast, the ones under proactive coupling are less volatile, but growing much slower and are less resilient. By reporting these regional economic dynamics, this paper argues that sustainability in late-coming regions cannot be explained by either intra-regional forces or the means of global integration alone. In contrast, it has to be explained by the combination of both; the alleged strategic coupling in which economic growth and learning happens. This paper thus calls for greater attention to strategic coupling, the trade-off of globalization and resilience for understanding regional sustainability, rather than purely focusing on resource utilization and ecological balance.

  4. Substance use changes and social role transitions: proximal developmental effects on ongoing trajectories from late adolescence through early adulthood.

    Science.gov (United States)

    Staff, Jeremy; Schulenberg, John E; Maslowsky, Julie; Bachman, Jerald G; O'Malley, Patrick M; Maggs, Jennifer L; Johnston, Lloyd D

    2010-11-01

    Substance use changes rapidly during late adolescence and early adulthood. This time in the life course is also dense with social role changes, as role changes provide dynamic context for individual developmental change. Using nationally representative, multiwave longitudinal data from age 18 to 28, we examine proximal links between changes in social roles and changes in substance use during the transition to adulthood. We find that changes in family roles, such as marriage, divorce, and parenthood, have clear and consistent associations with changes in substance use. With some notable exceptions, changes in school and work roles have weaker effects on changes in substance use compared to family roles. Changes in socializing (i.e., nights out for fun and recreation) and in religiosity were found to mediate the relationship of social role transitions to substance use. Two time-invariant covariates, socioeconomic background and heavy adolescent substance use, predicted social role status, but did not moderate associations, as within-person links between social roles and substance use were largely equivalent across groups. This paper adds to the cascading effects literature by considering how, within individuals, more proximal variations in school, work, and family roles relate to variations in substance use, and which roles appear to be most influential in precipitating changes in substance use during the transition to adulthood.

  5. Child anxiety symptoms related to longitudinal cortisol trajectories and acute stress responses: evidence of developmental stress sensitization.

    Science.gov (United States)

    Laurent, Heidemarie K; Gilliam, Kathryn S; Wright, Dorianne B; Fisher, Philip A

    2015-02-01

    Cross-sectional research suggests that individuals at risk for internalizing disorders show differential activation levels and/or dynamics of stress-sensitive physiological systems, possibly reflecting a process of stress sensitization. However, there is little longitudinal research to clarify how the development of these systems over time relates to activation during acute stress, and how aspects of such activation map onto internalizing symptoms. We investigated children's (n = 107) diurnal hypothalamic-pituitary-adrenal activity via salivary cortisol (morning and evening levels) across 29 assessments spanning 6+ years, and related longitudinal patterns to acute stress responses at the end of this period (age 9-10). Associations with child psychiatric symptoms at age 10 were also examined to determine internalizing risk profiles. Increasing morning cortisol levels across assessments predicted less of a cortisol decline following interpersonal stress at age 9, and higher cortisol levels during performance stress at age 10. These same profiles of high and/or sustained cortisol elevation during psychosocial stress were associated with child anxiety symptoms. Results suggest developmental sensitization to stress-reflected in rising morning cortisol and eventual hyperactivation during acute stress exposure-may distinguish children at risk for internalizing disorders. (PsycINFO Database Record (c) 2015 APA, all rights reserved).

  6. Substance Use Changes and Social Role Transitions: Proximal Developmental Effects on Ongoing Trajectories from Late Adolescence through Early Adulthood*

    Science.gov (United States)

    Staff, Jeremy; Schulenberg, John E.; Maslowsky, Julie; Bachman, Jerald G.; O’Malley, Patrick M.; Maggs, Jennifer L.; Johnston, Lloyd D.

    2010-01-01

    Substance use changes rapidly during late adolescence and early adulthood. Not coincidentally, this time in the life course is also dense with social role changes, as role changes provide dynamic context for individual developmental change. Using nationally representative, multiwave longitudinal data from age 18 to 28, we examine proximal links between changes in social roles and changes in substance use during the transition to adulthood. We find that changes in family roles, such as marriage, divorce, and parenthood, have clear and consistent associations with changes in substance use. With some notable exceptions, changes in school and work roles have weaker effects on changes in substance use compared to family roles. Changes in socializing (i.e., nights out for fun and recreation) and in religiosity were found to mediate the relationship of social role transitions to substance use. Two time- invariant covariates, socioeconomic background and heavy adolescent substance use, predicted social role status, but did not moderate associations, as within-person links between social roles and substance use were largely equivalent across groups. This paper adds to the cascading effects literature by considering how, within individuals, more proximal variations in school, work, and family roles relate to variations in substance use; and which roles appear to be most influential in precipitating changes in substance use during the transition to adulthood. PMID:20883590

  7. Multilevel risk factors and developmental assets for internalizing symptoms and self-esteem in disadvantaged adolescents: modeling longitudinal trajectories from the Rural Adaptation Project.

    Science.gov (United States)

    Smokowski, Paul R; Guo, Shenyang; Rose, Roderick; Evans, Caroline B R; Cotter, Katie L; Bacallao, Martica

    2014-11-01

    The current study filled significant gaps in our knowledge of developmental psychopathology by examining the influence of multilevel risk factors and developmental assets on longitudinal trajectories of internalizing symptoms and self-esteem in an exceptionally culturally diverse sample of rural adolescents. Integrating ecological and social capital theories, we explored if positive microsystem transactions are associated with self-esteem while negative microsystem transactions increase the chances of internalizing problems. Data came from the Rural Adaptation Project, a 5-year longitudinal panel study of more than 4,000 middle school students from 28 public schools in two rural, disadvantaged counties in North Carolina. Three-level hierarchical linear modeling models were estimated to predict internalizing symptoms (e.g., depression, anxiety) and self-esteem. Relative to other students, risk for internalizing problems and low self-esteem was elevated for aggressive adolescents, students who were hassled or bullied at school, and those who were rejected by peers or in conflict with their parents. Internalizing problems were also more common among adolescents from socioeconomically disadvantaged families and neighborhoods, among those in schools with more suspensions, in students who reported being pressured by peers, and in youth who required more teacher support. It is likely that these experiences left adolescents disengaged from developing social capital from ecological microsystems (e.g., family, school, peers). On the positive side, support from parents and friends and optimism about the future were key assets associated with lower internalizing symptoms and higher self-esteem. Self-esteem was also positively related to religious orientation, school satisfaction, and future optimism. These variables show active engagement with ecological microsystems. The implications and limitations were discussed.

  8. Is early adulthood a critical developmental stage for psychosis proneness? A survey of delusional ideation in normal subjects.

    Science.gov (United States)

    Verdoux, H; van Os, J; Maurice-Tison, S; Gay, B; Salamon, R; Bourgeois, M

    1998-02-09

    It has been hypothesized that late adolescence and early adulthood might be a brain developmental stage favoring the clinical expression of psychotic symptoms in psychiatric or neurological diseases. The aim of the present survey was to examine the relationship between age and delusional ideation in a sample of subjects with no psychiatric disorder. The survey was carried out with the Aquitaine Sentinel Network of general practitioners. Consecutive practice attenders were invited to complete the PDI-21 (Peters Delusional Inventory 21 items), a self-report questionnaire designed to measure delusional ideation in the normal population. The study concerned 444 patients who had no lifetime history of psychiatric disorder and who completed the PDI-21. A principal component analysis of the PDI-21 items was performed in order to identify delusional dimensions. An age-related decrease in the likelihood to report delusional ideas was found, younger subjects scoring higher on most dimensions of delusional ideation, such as 'persecution', 'thought disturbance', 'grandiosity' and 'paranormal beliefs'. 'Religiosity' was the only dimension positively associated with age. The results suggest that there may be a physiological neurodevelopmental stage favouring the expression of psychosis proneness in normal subjects, and support the hypothesis that the association between age and positive psychotic symptoms in functional and organic psychoses may be linked to the interaction between normal brain maturational processes and cerebral abnormalities involved in the aetiology of functional and organic psychoses.

  9. Genetic and developmental factors in spontaneous selective attention: a study of normal twins.

    Science.gov (United States)

    Myles-Worsley, M; Coon, H

    1997-08-08

    The Spontaneous Selective Attention Task (SSAT) is a visual word identification task designed to measure the type of selective attention that occurs spontaneously when there are multiple stimuli, all potentially relevant, and insufficient time to process each of them fully. These are conditions which are common in everyday life. SSAT performance is measured by word identification accuracy, first under a baseline divided attention condition with no predictability, then under a selective attention condition with partial predictability introduced via word repetition. Accuracy to identify novel words in the upper location which becomes partially predictable (P words) vs. the lower location which remains non-predictable (N words) can be used to calculate a baseline performance index and a P/N ratio measure of selective attention. The SSAT has been shown to identify an attentional abnormality that may be useful in the development of an attentional endophenotype for family-genetic studies of schizophrenia. This study examined age and genetic effects on SSAT performance in normal children in order to evaluate whether the SSAT has the potential to qualify as a candidate endophenotype for schizophrenia in studies of at-risk children. A total of 59 monozygotic twin pairs and 33 same-sex dizygotic twin pairs ranging from 10 to 18 years of age were tested on the SSAT, a Continuous Performance Test. (CPT), a Span of Apprehension Test (SPAN) and a full-scale IQ test. Baseline performance on the SSAT, which was correlated with verbal IQ and SPAN performance, improved with age but showed no significant heritability. The P/N selectivity ratio was stable over the 10-18-year age range, was not significantly correlated with IQ, CPT, or SPAN performance, and its heritability was estimated to be 0.41. These findings suggest that the P/N selectivity ratio measured by the SSAT may be useful as a vulnerability marker in studies of children born into families segregating schizophrenia.

  10. Developmental axon stretch stimulates neuron growth while maintaining normal electrical activity, intracellular calcium flux, and somatic morphology.

    Science.gov (United States)

    Loverde, Joseph R; Pfister, Bryan J

    2015-01-01

    Elongation of nerve fibers intuitively occurs throughout mammalian development, and is synchronized with expansion of the growing body. While most tissue systems enlarge through mitosis and differentiation, elongation of nerve fibers is remarkably unique. The emerging paradigm suggests that axons undergo stretch as contiguous tissues enlarge between the proximal and distal segments of spanning nerve fibers. While stretch is distinct from growth, tension is a known stimulus which regulates the growth of axons. Here, we hypothesized that the axon stretch-growth process may be a natural form of injury, whereby regenerative processes fortify elongating axons in order to prevent disconnection. Harnessing the live imaging capability of our axon stretch-growth bioreactors, we assessed neurons both during and following stretch for biomarkers associated with injury. Utilizing whole-cell patch clamp recording, we found no evidence of changes in spontaneous action potential activity or degradation of elicited action potentials during real-time axon stretch at strains of up to 18% applied over 5 min. Unlike traumatic axonal injury, functional calcium imaging of the soma revealed no shifts in free intracellular calcium during axon stretch. Finally, the cross-sectional areas of nuclei and cytoplasms were normal, with no evidence of chromatolysis following week-long stretch-growth limited to the lower of 25% strain or 3 mm total daily stretch. The neuronal growth cascade coupled to stretch was concluded to be independent of the changes in membrane potential, action potential generation, or calcium flux associated with traumatic injury. While axon stretch-growth is likely to share overlap with regenerative processes, we conclude that developmental stretch is a distinct stimulus from traumatic axon injury.

  11. Developmental Axon Stretch Stimulates Neuron Growth While Maintaining Normal Electrical Activity, Intracellular Calcium Flux, and Somatic Morphology

    Directory of Open Access Journals (Sweden)

    Joseph R Loverde

    2015-08-01

    Full Text Available Elongation of nerve fibers intuitively occurs throughout mammalian development, and is synchronized with expansion of the growing body. While most tissue systems enlarge through mitosis and differentiation, elongation of nerve fibers is remarkably unique. The emerging paradigm suggests that axons undergo stretch as contiguous tissues enlarge between the proximal and distal segments of spanning nerve fibers. While stretch is distinct from growth, tension is a known stimulus which regulates the growth of axons. Here, we hypothesized that the axon stretch-growth process may be a natural form of injury, whereby regenerative processes fortify elongating axons in order to prevent disconnection. Harnessing the live imaging capability of our axon stretch-growth bioreactors, we assessed neurons both during and following stretch for biomarkers associated with injury. Utilizing whole-cell patch clamp recording, we found no evidence of changes in spontaneous action potential activity or degradation of elicited action potentials during real-time axon stretch at strains of up to 18 % applied over 5 minutes. Unlike traumatic axonal injury, functional calcium imaging of the soma revealed no shifts in free intracellular calcium during axon stretch. Finally, the cross-sectional areas of nuclei and cytoplasms were normal, with no evidence of chromatolysis following week-long stretch-growth limited to the lower of 25 % strain or 3 mm total daily stretch. The neuronal growth cascade coupled to stretch was concluded to be independent of the changes in membrane potential, action potential generation, or calcium flux associated with traumatic injury. While axon stretch-growth is likely to share overlap with regenerative processes, we conclude that developmental stretch is a distinct stimulus from traumatic axon injury.

  12. Mouse model of chromosome mosaicism reveals lineage-specific depletion of aneuploid cells and normal developmental potential.

    Science.gov (United States)

    Bolton, Helen; Graham, Sarah J L; Van der Aa, Niels; Kumar, Parveen; Theunis, Koen; Fernandez Gallardo, Elia; Voet, Thierry; Zernicka-Goetz, Magdalena

    2016-03-29

    Most human pre-implantation embryos are mosaics of euploid and aneuploid cells. To determine the fate of aneuploid cells and the developmental potential of mosaic embryos, here we generate a mouse model of chromosome mosaicism. By treating embryos with a spindle assembly checkpoint inhibitor during the four- to eight-cell division, we efficiently generate aneuploid cells, resulting in embryo death during peri-implantation development. Live-embryo imaging and single-cell tracking in chimeric embryos, containing aneuploid and euploid cells, reveal that the fate of aneuploid cells depends on lineage: aneuploid cells in the fetal lineage are eliminated by apoptosis, whereas those in the placental lineage show severe proliferative defects. Overall, the proportion of aneuploid cells is progressively depleted from the blastocyst stage onwards. Finally, we show that mosaic embryos have full developmental potential, provided they contain sufficient euploid cells, a finding of significance for the assessment of embryo vitality in the clinic.

  13. Developmental Course of Impulsivity and Capability from Age 10 to Age 25 as Related to Trajectory of Suicide Attempt in a Community Cohort

    Science.gov (United States)

    Kasen, Stephanie; Cohen, Patricia; Chen, Henian

    2011-01-01

    Hierarchical linear models were used to examine trajectories of impulsivity and capability between ages 10 and 25 in relation to suicide attempt in 770 youths followed longitudinally: intercepts were set at age 17. The impulsivity measure assessed features of urgency (e.g., poor control, quick provocation, and disregard for external constraints);…

  14. Comparing Health Status, Health Trajectories and Use of Health and Social Services between Children with and without Developmental Disabilities: A Population-Based Longitudinal Study in Manitoba

    Science.gov (United States)

    Shooshtari, Shahin; Brownell, Marni; Mills, Rosemary S. L.; Dik, Natalia; Yu, Dickie C. T.; Chateau, Dan; Burchill, Charles A.; Wetzel, Monika

    2017-01-01

    Background: Little information exists on health of children with developmental disabilities (DDs) in the Canadian province of Manitoba. Method: The present authors linked 12 years of administrative data and compared health status, changes in health and access to health and social services between children with (n = 1877) and without (n = 5661) DDs…

  15. Weighing in on the Issue: A Longitudinal Analysis of the Influence of Selected Individual Factors and the Sports Context on the Developmental Trajectories of Eating Pathology among Adolescents

    Science.gov (United States)

    Fay, Kristen; Lerner, Richard M.

    2013-01-01

    Eating disorders, and related issues (e.g., body dissatisfaction, weight control behaviors), represent pressing and prevalent health problems that affect American adolescents with alarming frequency and potentially chronic consequences. However, more longitudinal research is needed to elucidate the developmental processes that increase or maintain…

  16. Developmental Course of Impulsivity and Capability from Age 10 to Age 25 as Related to Trajectory of Suicide Attempt in a Community Cohort

    OpenAIRE

    Kasen, Stephanie; Cohen, Patricia; Chen, Henian

    2011-01-01

    Hierarchical linear models were used to examine trajectories of impulsivity and capability between ages 10 and 25 in relation to suicide attempt in 770 youths followed longitudinally: intercepts were set at age 17. The impulsivity measure assessed features of urgency (e.g., poor control, quick provocation, and disregard for external constraints); the capability measure assessed aspects of self-esteem and mastery. Compared to nonattempters, attempters reported significantly higher impulsivity ...

  17. Evaluation of Suitable Reference Genes for Normalization of qPCR Gene Expression Studies in Brinjal (Solanum melongena L.) During Fruit Developmental Stages.

    Science.gov (United States)

    Kanakachari, Mogilicherla; Solanke, Amolkumar U; Prabhakaran, Narayanasamy; Ahmad, Israr; Dhandapani, Gurusamy; Jayabalan, Narayanasamy; Kumar, Polumetla Ananda

    2016-02-01

    Brinjal/eggplant/aubergine is one of the major solanaceous vegetable crops. Recent availability of genome information greatly facilitates the fundamental research on brinjal. Gene expression patterns during different stages of fruit development can provide clues towards the understanding of its biological functions. Quantitative real-time PCR (qPCR) has become one of the most widely used methods for rapid and accurate quantification of gene expression. However, its success depends on the use of a suitable reference gene for data normalization. For qPCR analysis, a single reference gene is not universally suitable for all experiments. Therefore, reference gene validation is a crucial step. Suitable reference genes for qPCR analysis of brinjal fruit development have not been investigated so far. In this study, we have selected 21 candidate reference genes from the Brinjal (Solanum melongena) Plant Gene Indices database (compbio.dfci.harvard.edu/tgi/plant.html) and studied their expression profiles by qPCR during six different fruit developmental stages (0, 5, 10, 20, 30, and 50 days post anthesis) along with leaf samples of the Pusa Purple Long (PPL) variety. To evaluate the stability of gene expression, geNorm and NormFinder analytical softwares were used. geNorm identified SAND (SAND family protein) and TBP (TATA binding protein) as the best pairs of reference genes in brinjal fruit development. The results showed that for brinjal fruit development, individual or a combination of reference genes should be selected for data normalization. NormFinder identified Expressed gene (expressed sequence) as the best single reference gene in brinjal fruit development. In this study, we have identified and validated for the first time reference genes to provide accurate transcript normalization and quantification at various fruit developmental stages of brinjal which can also be useful for gene expression studies in other Solanaceae plant species.

  18. Global developmental gene expression and pathway analysis of normal brain development and mouse models of human neuronal migration defects.

    Directory of Open Access Journals (Sweden)

    Tiziano Pramparo

    2011-03-01

    Full Text Available Heterozygous LIS1 mutations are the most common cause of human lissencephaly, a human neuronal migration defect, and DCX mutations are the most common cause of X-linked lissencephaly. LIS1 is part of a protein complex including NDEL1 and 14-3-3ε that regulates dynein motor function and microtubule dynamics, while DCX stabilizes microtubules and cooperates with LIS1 during neuronal migration and neurogenesis. Targeted gene mutations of Lis1, Dcx, Ywhae (coding for 14-3-3ε, and Ndel1 lead to neuronal migration defects in mouse and provide models of human lissencephaly, as well as aid the study of related neuro-developmental diseases. Here we investigated the developing brain of these four mutants and wild-type mice using expression microarrays, bioinformatic analyses, and in vivo/in vitro experiments to address whether mutations in different members of the LIS1 neuronal migration complex lead to similar and/or distinct global gene expression alterations. Consistent with the overall successful development of the mutant brains, unsupervised clustering and co-expression analysis suggested that cell cycle and synaptogenesis genes are similarly expressed and co-regulated in WT and mutant brains in a time-dependent fashion. By contrast, focused co-expression analysis in the Lis1 and Ndel1 mutants uncovered substantial differences in the correlation among pathways. Differential expression analysis revealed that cell cycle, cell adhesion, and cytoskeleton organization pathways are commonly altered in all mutants, while synaptogenesis, cell morphology, and inflammation/immune response are specifically altered in one or more mutants. We found several commonly dysregulated genes located within pathogenic deletion/duplication regions, which represent novel candidates of human mental retardation and neurocognitive disabilities. Our analysis suggests that gene expression and pathway analysis in mouse models of a similar disorder or within a common pathway can

  19. Gender identity disorder: a literature review from a developmental perspective.

    Science.gov (United States)

    Shechner, Tomer

    2010-01-01

    The present paper reviews the theoretical and empirical literature on children and adolescents with gender variant behaviors. The organizational framework underlying this review is one that presents gender behavior in children and adolescents as a continuum rather than as a dichotomy of normal versus abnormal categories. Seven domains are reviewed in relation to gender variant behavior in general, and to Gender Identity Disorder (GID) in particular: theories of normative gender development, phenomenology, prevalence, assessment, developmental trajectories, comorbidity and treatment.

  20. Developmental changes in hippocampal shape among preadolescent children.

    Science.gov (United States)

    Lin, Muqing; Fwu, Peter T; Buss, Claudia; Davis, Elysia P; Head, Kevin; Muftuler, L Tugan; Sandman, Curt A; Su, Min-Ying

    2013-11-01

    It is known that the largest developmental changes in the hippocampus take place during the prenatal period and during the first two years of postnatal life. Few studies have been conducted to address the normal developmental trajectory of the hippocampus during childhood. In this study shape analysis was applied to study the normal developing hippocampus in a group of 103 typically developing 6- to 10-year-old preadolescent children. The individual brain was normalized to a template, and then the hippocampus was manually segmented and further divided into the head, body, and tail sub-regions. Three different methods were applied for hippocampal shape analysis: radial distance mapping, surface-based template registration using the robust point matching (RPM) algorithm, and volume-based template registration using the Demons algorithm. All three methods show that the older children have bilateral expanded head segments compared to the younger children. The results analyzed based on radial distance to the centerline were consistent with those analyzed using template-based registration methods. In analyses stratified by sex, it was found that the age-associated anatomical changes were similar in boys and girls, but the age-association was strongest in girls. Total hippocampal volume and sub-regional volumes analyzed using manual segmentation did not show a significant age-association. Our results suggest that shape analysis is sensitive to detect sub-regional differences that are not revealed in volumetric analysis. The three methods presented in this study may be applied in future studies to investigate the normal developmental trajectory of the hippocampus in children. They may be further applied to detect early deviations from the normal developmental trajectory in young children for evaluating susceptibility for psychopathological disorders involving hippocampus. Copyright © 2013 ISDN. Published by Elsevier Ltd. All rights reserved.

  1. Developmental Readiness of Normal Full Term Infants To Progress from Exclusive Breastfeeding to the Introduction of Complementary Foods: Reviews of the Relevant Literature Concerning Infant Immunologic, Gastrointestinal, Oral Motor and Maternal Reproductive and Lactational Development.

    Science.gov (United States)

    Naylor, Audrey J., Ed.; Morrow, Ardythe L., Ed.

    This review of the developmental readiness of normal, full-term infants to progress from exclusive breastfeeding to the introduction of complementary foods is the result of the international debate regarding the best age to introduce complementary foods into the diet of the breastfed human infant. After a list of definitions, four papers focus on:…

  2. Describing normal development in an African setting : The utility of the Kilifi Developmental Inventory among young children at the Kenyan coast

    NARCIS (Netherlands)

    Kitsao-Wekulo, Patricia; Holding, Penny; Abubakar, Amina; Kvalsvig, Jane; Taylor, H. Gerry; King, Christopher L.

    The Kilifi Developmental Inventory (KDI) is a tool developed in Kenya for the assessment of psychomotor development in infants and young children. We developed age-appropriate standards against which the developmental progress of individual children could be tracked. The current report is based on

  3. Does the optimal position of the acetabular fragment should be within the radiological normal range for all developmental dysplasia of the hip? A patient-specific finite element analysis.

    Science.gov (United States)

    Wang, Xuyi; Peng, Jianping; Li, De; Zhang, Linlin; Wang, Hui; Jiang, Leisheng; Chen, Xiaodong

    2016-10-04

    The success of Bernese periacetabular osteotomy depends significantly on how extent the acetabular fragment can be corrected to its optimal position. This study was undertaken to investigate whether correcting the acetabular fragment into the so-called radiological "normal" range is the best choice for all developmental dysplasia of the hip with different severities of dysplasia from the biomechanical view? If not, is there any correlation between the biomechanically optimal position of the acetabular fragment and the severity of dysplasia? Four finite element models with different severities of dysplasia were developed. The virtual periacetabular osteotomy was performed with the acetabular fragment rotated anterolaterally to incremental center-edge angles; then, the contact area and pressure and von Mises stress in the cartilage were calculated at different correction angles. The optimal position of the acetabular fragment for patients 1, 2, and 3 was when the acetabular fragment rotated 17° laterally (with the lateral center-edge angle of 36° and anterior center-edge angle of 58°; both were slightly larger than the "normal" range), 25° laterally following further 5° anterior rotation (with the lateral center-edge angle of 31° and anterior center-edge angle of 51°; both were within the "normal" range), and 30° laterally following further 10° anterior rotation (with the lateral center-edge angle of 25° and anterior center-edge angle of 40°; both were less than the "normal" range), respectively. The optimal corrective position of the acetabular fragment is severity dependent rather than within the radiological "normal" range for developmental dysplasia of the hip. We prudently proposed that the optimal correction center-edge angle of mild, moderate, and severe developmental dysplasia of the hip is slightly larger than the "normal" range, within the "normal" range, and less than the lower limit of the "normal" range, respectively.

  4. PREVALENCE OF REFRACTIVE ERROR, STRABISMUS AND AMBLYOPIA AMONG CHILDREN WITH NORMAL DEVELOPMENT OR GLOBAL DEVELOPMENTAL DELAY/INTELLECTUAL DISABILITY ATTENDING OPHTHALMOLOGY OPD AT KLES HOSPITAL, BELAGAVI- A RETROSPECTIVE STUDY

    Directory of Open Access Journals (Sweden)

    Smitha K. S

    2017-04-01

    Full Text Available BACKGROUND Global developmental delay/intellectual disability are on a rise in children in the present time. Ocular and visual anomalies are frequently associated with it of which refractive errors are the most frequent. This if goes unnoticed leads to strabismus and amblyopia. MATERIALS AND METHODS This study aims to assess the prevalence of refractive error, strabismus and amblyopia among children with normal development or global developmental delay/intellectual disability attending ophthalmology OPD at KLES Hospital, Belagavi. Case records of all 200 new patients less than or equal to 12 years of age group who attended KLES, Dr. Prabhakar Kore Hospital between January 2015 and December 2015 were retrospectively reviewed. RESULTS The male:female ratio was 1.22:1. Out of the total evaluated 200 cases, 130 cases were with normal development and 70 with GDD/ID. Refractive errors were 85%, whereas the cases of amblyopia was 45.50% and strabismus 39.50%. Amblyopia with refractive error having GDD/ID was stastically significant as compared to amblyopia with refractive error having normal development (p=0.001. CONCLUSION Refractive error was the most common ocular disorder seen. Refractive error with amblyopia is more in children with GDD/ID as compared to normal children. Owing to the high percentage of visual anomalies, ophthalmological referral becomes essential in children with developmental anomalies.

  5. The Developmental Trajectory of Nonword Repetition

    Science.gov (United States)

    Chiat, Shula

    2006-01-01

    In line with the original presentation of nonword repetition as a measure of phonological short-term memory (Gathercole & Baddeley, 1989), the theoretical account Gathercole (2006) puts forward in her Keynote Article focuses on phonological storage as the key capacity common to nonword repetition and vocabulary acquisition. However, evidence that…

  6. Probabilistic maps of the white matter tracts with known associated functions on the neonatal brain atlas: Application to evaluate longitudinal developmental trajectories in term-born and preterm-born infants.

    Science.gov (United States)

    Akazawa, Kentaro; Chang, Linda; Yamakawa, Robyn; Hayama, Sara; Buchthal, Steven; Alicata, Daniel; Andres, Tamara; Castillo, Deborrah; Oishi, Kumiko; Skranes, Jon; Ernst, Thomas; Oishi, Kenichi

    2016-03-01

    Diffusion tensor imaging (DTI) has been widely used to investigate the development of the neonatal and infant brain, and deviations related to various diseases or medical conditions like preterm birth. In this study, we created a probabilistic map of fiber pathways with known associated functions, on a published neonatal multimodal atlas. The pathways-of-interest include the superficial white matter (SWM) fibers just beneath the specific cytoarchitectonically defined cortical areas, which were difficult to evaluate with existing DTI analysis methods. The Jülich cytoarchitectonic atlas was applied to define cortical areas related to specific brain functions, and the Dynamic Programming (DP) method was applied to delineate the white matter pathways traversing through the SWM. Probabilistic maps were created for pathways related to motor, somatosensory, auditory, visual, and limbic functions, as well as major white matter tracts, such as the corpus callosum, the inferior fronto-occipital fasciculus, and the middle cerebellar peduncle, by delineating these structures in eleven healthy term-born neonates. In order to characterize maturation-related changes in diffusivity measures of these pathways, the probabilistic maps were then applied to DTIs of 49 healthy infants who were longitudinally scanned at three time-points, approximately five weeks apart. First, we investigated the normal developmental pattern based on 19 term-born infants. Next, we analyzed 30 preterm-born infants to identify developmental patterns related to preterm birth. Last, we investigated the difference in diffusion measures between these groups to evaluate the effects of preterm birth on the development of these functional pathways. Term-born and preterm-born infants both demonstrated a time-dependent decrease in diffusivity, indicating postnatal maturation in these pathways, with laterality seen in the corticospinal tract and the optic radiation. The comparison between term- and preterm

  7. A roadmap for the integration of culture into developmental psychopathology.

    Science.gov (United States)

    Causadias, José M

    2013-11-01

    In this paper, I propose a roadmap for the integration of culture in developmental psychopathology. This integration is pressing because culture continues to be somewhat disconnected from theory, research, training, and interventions in developmental psychopathology, thus limiting our understanding of the epigenesis of mental health. I argue that in order to successfully integrate culture into developmental psychopathology, it is crucial to (a) study cultural development, (b) consider both individual-level and social-level cultural processes, (c) examine the interplay between culture and biology, and (d) promote improved and direct cultural assessment. I provide evidence in support of each of these guidelines, present alternative conceptual frameworks, and suggest new lines of research. Hopefully, that these directions will contribute to the emerging field of cultural development and psychopathology, which focuses on the elucidation of the cultural processes that initiate, maintain, or derail trajectories of normal and abnormal behavior.

  8. Predictors of Latent Trajectory Classes of Physical Dating Violence Victimization

    Science.gov (United States)

    Brooks-Russell, Ashley; Foshee, Vangie A.; Ennett, Susan T.

    2013-01-01

    This study identified classes of developmental trajectories of physical dating violence victimization from grades 8 to 12 and examined theoretically-based risk factors that distinguished among trajectory classes. Data were from a multi-wave longitudinal study spanning 8th through 12th grade (n = 2,566; 51.9 % female). Growth mixture models were…

  9. Identification of a developmental gene expression signature, including HOX genes, for the normal human colonic crypt stem cell niche: overexpression of the signature parallels stem cell overpopulation during colon tumorigenesis.

    Science.gov (United States)

    Bhatlekar, Seema; Addya, Sankar; Salunek, Moreh; Orr, Christopher R; Surrey, Saul; McKenzie, Steven; Fields, Jeremy Z; Boman, Bruce M

    2014-01-15

    Our goal was to identify a unique gene expression signature for human colonic stem cells (SCs). Accordingly, we determined the gene expression pattern for a known SC-enriched region--the crypt bottom. Colonic crypts and isolated crypt subsections (top, middle, and bottom) were purified from fresh, normal, human, surgical specimens. We then used an innovative strategy that used two-color microarrays (∼18,500 genes) to compare gene expression in the crypt bottom with expression in the other crypt subsections (middle or top). Array results were validated by PCR and immunostaining. About 25% of genes analyzed were expressed in crypts: 88 preferentially in the bottom, 68 in the middle, and 131 in the top. Among genes upregulated in the bottom, ∼30% were classified as growth and/or developmental genes including several in the PI3 kinase pathway, a six-transmembrane protein STAMP1, and two homeobox (HOXA4, HOXD10) genes. qPCR and immunostaining validated that HOXA4 and HOXD10 are selectively expressed in the normal crypt bottom and are overexpressed in colon carcinomas (CRCs). Immunostaining showed that HOXA4 and HOXD10 are co-expressed with the SC markers CD166 and ALDH1 in cells at the normal crypt bottom, and the number of these co-expressing cells is increased in CRCs. Thus, our findings show that these two HOX genes are selectively expressed in colonic SCs and that HOX overexpression in CRCs parallels the SC overpopulation that occurs during CRC development. Our study suggests that developmental genes play key roles in the maintenance of normal SCs and crypt renewal, and contribute to the SC overpopulation that drives colon tumorigenesis.

  10. Growth Trajectories of Health Behaviors from Adolescence through Young Adulthood.

    Science.gov (United States)

    Wiium, Nora; Breivik, Kyrre; Wold, Bente

    2015-10-28

    Based on nine waves of data collected during a period of 17 years (1990-2007), the present study explored different developmental trajectories of the following unhealthy behaviors: regular smoking, lack of regular exercise, lack of daily fruit intake, and drunkenness. A baseline sample of 1195 13-year-old pupils was from 22 randomly selected schools in the Hordaland County in western Norway. Latent class growth analysis revealed three developmental trajectories. The first trajectory was a conventional trajectory, comprising 36.3% of participants, who showed changes in smoking, physical exercise, fruit intake, and drunkenness consistent with the prevailing age specific norms of these behaviors in the Norwegian society at the time. The second trajectory was a passive trajectory, comprising 25.5% of participants, who reported low levels of both healthy and unhealthy behaviors during the 17-year period. The third trajectory was an unhealthy trajectory, comprising 38.2% of participants, who had high levels of unhealthy behaviors over time. Several covariates were examined, but only sex and mother's and father's educational levels were found to be significantly associated with the identified trajectories. While these findings need to be replicated in future studies, the identification of the different trajectories suggests the need to tailor intervention according to specific needs.

  11. Growth Trajectories of Health Behaviors from Adolescence through Young Adulthood

    Directory of Open Access Journals (Sweden)

    Nora Wiium

    2015-10-01

    Full Text Available Based on nine waves of data collected during a period of 17 years (1990–2007, the present study explored different developmental trajectories of the following unhealthy behaviors: regular smoking, lack of regular exercise, lack of daily fruit intake, and drunkenness. A baseline sample of 1195 13-year-old pupils was from 22 randomly selected schools in the Hordaland County in western Norway. Latent class growth analysis revealed three developmental trajectories. The first trajectory was a conventional trajectory, comprising 36.3% of participants, who showed changes in smoking, physical exercise, fruit intake, and drunkenness consistent with the prevailing age specific norms of these behaviors in the Norwegian society at the time. The second trajectory was a passive trajectory, comprising 25.5% of participants, who reported low levels of both healthy and unhealthy behaviors during the 17-year period. The third trajectory was an unhealthy trajectory, comprising 38.2% of participants, who had high levels of unhealthy behaviors over time. Several covariates were examined, but only sex and mother’s and father’s educational levels were found to be significantly associated with the identified trajectories. While these findings need to be replicated in future studies, the identification of the different trajectories suggests the need to tailor intervention according to specific needs.

  12. Growth Trajectories of Health Behaviors from Adolescence through Young Adulthood

    Science.gov (United States)

    Wiium, Nora; Breivik, Kyrre; Wold, Bente

    2015-01-01

    Based on nine waves of data collected during a period of 17 years (1990–2007), the present study explored different developmental trajectories of the following unhealthy behaviors: regular smoking, lack of regular exercise, lack of daily fruit intake, and drunkenness. A baseline sample of 1195 13-year-old pupils was from 22 randomly selected schools in the Hordaland County in western Norway. Latent class growth analysis revealed three developmental trajectories. The first trajectory was a conventional trajectory, comprising 36.3% of participants, who showed changes in smoking, physical exercise, fruit intake, and drunkenness consistent with the prevailing age specific norms of these behaviors in the Norwegian society at the time. The second trajectory was a passive trajectory, comprising 25.5% of participants, who reported low levels of both healthy and unhealthy behaviors during the 17-year period. The third trajectory was an unhealthy trajectory, comprising 38.2% of participants, who had high levels of unhealthy behaviors over time. Several covariates were examined, but only sex and mother’s and father’s educational levels were found to be significantly associated with the identified trajectories. While these findings need to be replicated in future studies, the identification of the different trajectories suggests the need to tailor intervention according to specific needs. PMID:26516889

  13. Insulin sensitivity is normalized in the third generation (F3 offspring of developmentally programmed insulin resistant (F2 rats fed an energy-restricted diet

    Directory of Open Access Journals (Sweden)

    Martin John F

    2008-10-01

    Full Text Available Abstract Background/Aims The offspring and grandoffspring of female rats fed low protein diets during pregnancy and lactation, but fed nutritionally adequate diets thereafter, have been shown to exhibit altered insulin sensitivity in adulthood. The current study investigates the insulin sensitivity of the offspring and grandoffspring of female rats fed low protein diets during pregnancy, and then maintained on energy-restricted diets post weaning over three generations. Methods Female Sprague Dawley rats (F0 were mated with control males and protein malnourished during pregnancy/lactation. F1 offspring were then weaned to adequate but energy-restricted diets into adulthood. F1 dams were fed energy-restricted diets throughout pregnancy/lactation. F2 offspring were also fed energy-restricted diets post weaning. F2 pregnant dams were maintained as described above. Their F3 offspring were split into two groups; one was maintained on the energy-restricted diet, the other was maintained on an adequate diet consumed ad libitum post weaning. Results F2 animals fed energy-restricted diets were insulin resistant (p ad libitum postweaning diets (p Conclusion Maternal energy-restriction did not consistently program reduced insulin sensitivity in offspring over three consecutive generations. The reasons for this remain unclear. It is possible that the intergenerational transmission of developmentally programmed insulin resistance is determined in part by the relative insulin sensitivity of the mother during pregnancy/lactation.

  14. Management by Trajectory: Trajectory Management Study Report

    Science.gov (United States)

    Leiden, Kenneth; Atkins, Stephen; Fernandes, Alicia D.; Kaler, Curt; Bell, Alan; Kilbourne, Todd; Evans, Mark

    2017-01-01

    In order to realize the full potential of the Next Generation Air Transportation System (NextGen), improved management along planned trajectories between air navigation service providers (ANSPs) and system users (e.g., pilots and airline dispatchers) is needed. Future automation improvements and increased data communications between aircraft and ground automation would make the concept of Management by Trajectory (MBT) possible.

  15. Developmental expression and differentiation-related neuron-specific splicing of metastasis suppressor 1 (Mtss1 in normal and transformed cerebellar cells

    Directory of Open Access Journals (Sweden)

    Baader Stephan L

    2007-10-01

    Full Text Available Abstract Background Mtss1 encodes an actin-binding protein, dysregulated in a variety of tumors, that interacts with sonic hedgehog/Gli signaling in epidermal cells. Given the prime importance of this pathway for cerebellar development and tumorigenesis, we assessed expression of Mtss1 in the developing murine cerebellum and human medulloblastoma specimens. Results During development, Mtss1 is transiently expressed in granule cells, from the time point they cease to proliferate to their synaptic integration. It is also expressed by granule cell precursor-derived medulloblastomas. In the adult CNS, Mtss1 is found exclusively in cerebellar Purkinje cells. Neuronal differentiation is accompanied by a switch in Mtss1 splicing. Whereas immature granule cells express a Mtss1 variant observed also in peripheral tissues and comprising exon 12, this exon is replaced by a CNS-specific exon, 12a, in more mature granule cells and in adult Purkinje cells. Bioinformatic analysis of Mtss1 suggests that differential exon usage may affect interaction with Fyn and Src, two tyrosine kinases previously recognized as critical for cerebellar cell migration and histogenesis. Further, this approach led to the identification of two evolutionary conserved nuclear localization sequences. These overlap with the actin filament binding site of Mtss1, and one also harbors a potential PKA and PKC phosphorylation site. Conclusion Both the pattern of expression and splicing of Mtss1 is developmentally regulated in the murine cerebellum. These findings are discussed with a view on the potential role of Mtss1 for cytoskeletal dynamics in developing and mature cerebellar neurons.

  16. Adaptive Trajectory Design

    Data.gov (United States)

    National Aeronautics and Space Administration — Adaptive Trajectory Design (ATD) is an original concept for quick and efficient end-to-end trajectory designs using proven piece-wise dynamical methods. With ongoing...

  17. Computing with spatial trajectories

    CERN Document Server

    2011-01-01

    Covers the fundamentals and the state-of-the-art research inspired by the spatial trajectory data Readers are provided with tutorial-style chapters, case studies and references to other relevant research work This is the first book that presents the foundation dealing with spatial trajectories and state-of-the-art research and practices enabled by trajectories

  18. Developmental changes in organization of structural brain networks.

    Science.gov (United States)

    Khundrakpam, Budhachandra S; Reid, Andrew; Brauer, Jens; Carbonell, Felix; Lewis, John; Ameis, Stephanie; Karama, Sherif; Lee, Junki; Chen, Zhang; Das, Samir; Evans, Alan C

    2013-09-01

    Recent findings from developmental neuroimaging studies suggest that the enhancement of cognitive processes during development may be the result of a fine-tuning of the structural and functional organization of brain with maturation. However, the details regarding the developmental trajectory of large-scale structural brain networks are not yet understood. Here, we used graph theory to examine developmental changes in the organization of structural brain networks in 203 normally growing children and adolescents. Structural brain networks were constructed using interregional correlations in cortical thickness for 4 age groups (early childhood: 4.8-8.4 year; late childhood: 8.5-11.3 year; early adolescence: 11.4-14.7 year; late adolescence: 14.8-18.3 year). Late childhood showed prominent changes in topological properties, specifically a significant reduction in local efficiency, modularity, and increased global efficiency, suggesting a shift of topological organization toward a more random configuration. An increase in number and span of distribution of connector hubs was found in this age group. Finally, inter-regional connectivity analysis and graph-theoretic measures indicated early maturation of primary sensorimotor regions and protracted development of higher order association and paralimbic regions. Our finding reveals a time window of plasticity occurring during late childhood which may accommodate crucial changes during puberty and the new developmental tasks that an adolescent faces.

  19. Arguments from Developmental Order.

    Science.gov (United States)

    Stöckle-Schobel, Richard

    2016-01-01

    In this article, I investigate a special type of argument regarding the role of development in theorizing about psychological processes and cognitive capacities. Among the issues that developmental psychologists study, discovering the ontogenetic trajectory of mechanisms or capacities underpinning our cognitive functions ranks highly. The order in which functions are developed or capacities are acquired is a matter of debate between competing psychological theories, and also philosophical conceptions of the mind - getting the role and the significance of the different steps in this order right could be seen as an important virtue of such theories. Thus, a special kind of strategy in arguments between competing philosophical or psychological theories is using developmental order in arguing for or against a given psychological claim. In this article, I will introduce an analysis of arguments from developmental order, which come in two general types: arguments emphasizing the importance of the early cognitive processes and arguments emphasizing the late cognitive processes. I will discuss their role in one of the central tools for evaluating scientific theories, namely in making inferences to the best explanation. I will argue that appeal to developmental order is, by itself, an insufficient criterion for theory choice and has to be part of an argument based on other core explanatory or empirical virtues. I will end by proposing a more concerted study of philosophical issues concerning (cognitive) development, and I will present some topics that also pertain to a full-fledged 'philosophy of development.'

  20. Arguments from Developmental Order

    Directory of Open Access Journals (Sweden)

    Richard eStöckle-Schobel

    2016-05-01

    Full Text Available In this article, I investigate a special type of argument regarding the role of development in theorising about psychological processes and cognitive capacities. Among the issues that developmental psychologists study, discovering the ontogenetic trajectory of mechanisms or capacities underpinning our cognitive functions ranks highly. The order in which functions are developed or capacities are acquired is a matter of debate between competing psychological theories, and also philosophical conceptions of the mind – getting the role and the significance of the different steps in this order right could be seen as an important virtue of such theories.Thus, a special kind of strategy in arguments between competing philosophical or psychological theories is using developmental order in arguing for or against a given psychological claim. In this article, I will introduce an analysis of arguments from developmental order, which come in two general types: arguments emphasising the importance of the early cognitive processes and arguments emphasising the late cognitive processes. I will discuss their role in one of the central tools for evaluating scientific theories, namely in making inferences to the best explanation. I will argue that appeal to developmental order is, by itself, an insufficient criterion for theory choice and has to be part of an argument based on other core explanatory or empirical virtues. I will end by proposing a more concerted study of philosophical issues concerning (cognitive development, and I will present some topics that also pertain to a full-fledged ‘philosophy of development’.

  1. Romantic attraction and adolescent smoking trajectories.

    Science.gov (United States)

    Pollard, Michael S; Tucker, Joan S; Green, Harold D; Kennedy, David P; Go, Myong-Hyun

    2011-12-01

    Research on sexual orientation and substance use has established that lesbian, gay, and bisexual (LGB) individuals are more likely to smoke than heterosexuals. This analysis furthers the examination of smoking behaviors across sexual orientation groups by describing how same- and opposite-sex romantic attraction, and changes in romantic attraction, are associated with distinct six-year developmental trajectories of smoking. The National Longitudinal Study of Adolescent Health dataset is used to test our hypotheses. Multinomial logistic regressions predicting smoking trajectory membership as a function of romantic attraction were separately estimated for men and women. Romantic attraction effects were found only for women. The change from self-reported heterosexual attraction to lesbian or bisexual attraction was more predictive of higher smoking trajectories than was a consistent lesbian or bisexual attraction, with potentially important differences between the smoking patterns of these two groups. Copyright © 2011 Elsevier Ltd. All rights reserved.

  2. Friendship networks and trajectories of adolescent tobacco use.

    Science.gov (United States)

    Pollard, Michael S; Tucker, Joan S; Green, Harold D; Kennedy, David; Go, Myong-Hyun

    2010-07-01

    This article examines how friendship networks in adolescence are linked to tobacco use trajectories through a combination of analytic techniques that traditionally are located in separate literatures: social network analysis and developmental trajectory analysis. Using six years of longitudinal data from the National Longitudinal Study of Adolescent Health, we identify a set of six unique developmental trajectories of smoking (never smokers, steady lows, delayed increasers, early increasers, decreasers, and steady highs). Individuals' locations in their friendship networks were then linked to their trajectory group membership. Adolescents with a greater number of smoking friends were more likely to belong to the higher use trajectories. Beyond this exposure to smoking peers, individuals who at baseline were either members of a smoking group or liaisons to a smoking group were more likely than members of a nonsmoking group to belong to the higher use trajectories. Liaisons to a smoking group were particularly likely to belong to the delayed increaser trajectory group. Trajectory group membership for adolescents who belonged to a nonsmoking group did not significantly differ from those who were isolates or liaisons to a nonsmoking group. The study suggests features of an individual's social network have long-lasting associations with smoking behaviors. 2010 Elsevier Ltd. All rights reserved.

  3. Applying a Lifespan Developmental Perspective to Chronic Pain: Pediatrics to Geriatrics.

    Science.gov (United States)

    Walco, Gary A; Krane, Elliot J; Schmader, Kenneth E; Weiner, Debra K

    2016-09-01

    An ideal taxonomy of chronic pain would be applicable to people of all ages. Developmental sciences focus on lifespan developmental approaches, and view the trajectory of processes in the life course from birth to death. In this article we provide a review of lifespan developmental models, describe normal developmental processes that affect pain processing, and identify deviations from those processes that lead to stable individual differences of clinical interest, specifically the development of chronic pain syndromes. The goals of this review were 1) to unify what are currently separate purviews of "pediatric pain," "adult pain," and "geriatric pain," and 2) to generate models so that specific elements of the chronic pain taxonomy might include important developmental considerations. A lifespan developmental model is applied to the forthcoming Analgesic, Anesthetic, and Addiction Clinical Trial Translations, Innovations, Opportunities, and Networks-American Pain Society Pain Taxonomy to ascertain the degree to which general "adult" descriptions apply to pediatric and geriatric populations, or if age- or development-related considerations need to be invoked. Copyright © 2016. Published by Elsevier Inc.

  4. Trajectories of martian habitability.

    Science.gov (United States)

    Cockell, Charles S

    2014-02-01

    Beginning from two plausible starting points-an uninhabited or inhabited Mars-this paper discusses the possible trajectories of martian habitability over time. On an uninhabited Mars, the trajectories follow paths determined by the abundance of uninhabitable environments and uninhabited habitats. On an inhabited Mars, the addition of a third environment type, inhabited habitats, results in other trajectories, including ones where the planet remains inhabited today or others where planetary-scale life extinction occurs. By identifying different trajectories of habitability, corresponding hypotheses can be described that allow for the various trajectories to be disentangled and ultimately a determination of which trajectory Mars has taken and the changing relative abundance of its constituent environments.

  5. Lunar and interplanetary trajectories

    CERN Document Server

    Biesbroek, Robin

    2016-01-01

    This book provides readers with a clear description of the types of lunar and interplanetary trajectories, and how they influence satellite-system design. The description follows an engineering rather than a mathematical approach and includes many examples of lunar trajectories, based on real missions. It helps readers gain an understanding of the driving subsystems of interplanetary and lunar satellites. The tables and graphs showing features of trajectories make the book easy to understand. .

  6. Gestational Hyperandrogenism in Developmental Programming

    Science.gov (United States)

    Hakim, Christopher; Padmanabhan, Vasantha

    2017-01-01

    Androgen excess (hyperandrogenism) is a common endocrine disorder affecting women of reproductive age. The potential causes of androgen excess in women include polycystic ovary syndrome, congenital adrenal hyperplasia (CAH), adrenal tumors, and racial disparity among many others. During pregnancy, luteoma, placental aromatase deficiency, and fetal CAH are additional causes of gestational hyperandrogenism. The present report reviews the various phenotypes of hyperandrogenism during pregnancy and its origin, pathophysiology, and the effect of hyperandrogenism on the fetal developmental trajectory and offspring consequences. PMID:27967205

  7. Tendências da aquisição lexical em crianças em desenvolvimento normal e crianças com Alterações Específicas no Desenvolvimento da Linguagem Trends on lexical acquisition in children within normal development and children with developmental language disorder

    Directory of Open Access Journals (Sweden)

    Juliana Perina Gândara

    2010-01-01

    Full Text Available O objetivo do presente estudo foi descrever as semelhanças e diferenças encontradas ao longo da aquisição lexical por crianças em desenvolvimento normal e crianças com Alterações Específicas no Desenvolvimento da Linguagem (AEDL, por meio de um amplo levantamento bibliográfico em bases de dados (SciELO, Lilacs, PubMed, Web of Science, Dedalus, que abrangeu as últimas décadas de estudos na área. Os estudos selecionados, de natureza observacional ou experimental, mostraram grande variedade de achados relacionados ao desenvolvimento do vocabulário, abrangendo as tendências e variações e também outras habilidades envolvidas no processo de aquisição lexical. De maneira geral, os resultados sugerem que as alterações lexicais que constituem um dos marcos inicialmente observados em crianças com AEDL são justificadas por dificuldades observadas em habilidades e/ou características influenciadas ou diretamente relacionadas aos mecanismos envolvidos no processamento da informação, que comprometem a qualidade e a recuperação das representações fonológicas e semânticas correspondentes a um novo item lexical. Entretanto, vários estudos sugerem que situações ostensivas e de grande suporte contextual que enfoquem poucas novas palavras favorecem a aquisição lexical de crianças com AEDL.The aim of the present study was to describe the similarities and differences found throughout lexical acquisition between normally developing children and children with developmental language disorder through an extensive literature review. The search was carried out in the databases SciELO, Lilacs, PubMed, Web of Science and Dedalus, and covered the last decades of studies in the area. The selected studies, of observational or experimental nature, showed great variability of findings related to vocabulary development, describing tendencies and variations, and also other abilities enrolled in the lexical acquisition process. Generally, the

  8. PANTHER. Trajectory Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Rintoul, Mark Daniel [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Wilson, Andrew T. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Valicka, Christopher G. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Kegelmeyer, W. Philip [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Shead, Timothy M. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Newton, Benjamin D. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Czuchlewski, Kristina Rodriguez [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)

    2015-09-01

    We want to organize a body of trajectories in order to identify, search for, classify and predict behavior among objects such as aircraft and ships. Existing compari- son functions such as the Fr'echet distance are computationally expensive and yield counterintuitive results in some cases. We propose an approach using feature vectors whose components represent succinctly the salient information in trajectories. These features incorporate basic information such as total distance traveled and distance be- tween start/stop points as well as geometric features related to the properties of the convex hull, trajectory curvature and general distance geometry. Additionally, these features can generally be mapped easily to behaviors of interest to humans that are searching large databases. Most of these geometric features are invariant under rigid transformation. We demonstrate the use of different subsets of these features to iden- tify trajectories similar to an exemplar, cluster a database of several hundred thousand trajectories, predict destination and apply unsupervised machine learning algorithms.

  9. Developmental Immunotoxicity

    Science.gov (United States)

    Animal models suggest that the immature immune system is more susceptible to xenobiotics than the fully mature system, and sequelae of developmental immunotoxicant exposure may be persistent well into adulthood. Immune maturation may be delayed by xenobiotic exposure and recover...

  10. Trajectory Browser Website

    Science.gov (United States)

    Foster, Cyrus; Jaroux, Belgacem A.

    2012-01-01

    The Trajectory Browser is a web-based tool developed at the NASA Ames Research Center to be used for the preliminary assessment of trajectories to small-bodies and planets and for providing relevant launch date, time-of-flight and V requirements. The site hosts a database of transfer trajectories from Earth to asteroids and planets for various types of missions such as rendezvous, sample return or flybys. A search engine allows the user to find trajectories meeting desired constraints on the launch window, mission duration and delta V capability, while a trajectory viewer tool allows the visualization of the heliocentric trajectory and the detailed mission itinerary. The anticipated user base of this tool consists primarily of scientists and engineers designing interplanetary missions in the context of pre-phase A studies, particularly for performing accessibility surveys to large populations of small-bodies. The educational potential of the website is also recognized for academia and the public with regards to trajectory design, a field that has generally been poorly understood by the public. The website is currently hosted on NASA-internal URL http://trajbrowser.arc.nasa.gov/ with plans for a public release as soon as development is complete.

  11. Academic trajectories of newcomer immigrant youth.

    Science.gov (United States)

    Suárez-Orozco, Carola; Gaytán, Francisco X; Bang, Hee Jin; Pakes, Juliana; O'Connor, Erin; Rhodes, Jean

    2010-05-01

    Immigration to the United States presents both challenges and opportunities that affect students' academic achievement. Using a 5-year longitudinal, mixed-methods approach, we identified varying academic trajectories of newcomer immigrant students from Central America, China, the Dominican Republic, Haiti, and Mexico. Latent class growth curve analysis revealed that although some newcomer students performed at high or improving levels over time, others showed diminishing performance. Multinomial logistic regressions identified significant group differences in academic trajectories, particularly between the high-achieving youth and the other groups. In keeping with ecological-developmental and stage-environment fit theories, School Characteristics (school segregation rate, school poverty rate, and student perceptions of school violence), Family Characteristics (maternal education, parental employment, and household structure), and Individual Characteristics (academic English proficiency, academic engagement, psychological symptoms, gender, and 2 age-related risk factors, number of school transitions and being overaged for grade placement) were associated with different trajectories of academic performance. A series of case studies triangulate many of the quantitative findings as well as illuminate patterns that were not detected in the quantitative data. Thus, the mixed-methods approach sheds light on the cumulative developmental challenges that immigrant students face as they adjust to their new educational settings. 2010 APA, all rights reserved

  12. Long range trajectories

    Energy Technology Data Exchange (ETDEWEB)

    Allen, P. W.; Jessup, E. A.; White, R. E. [Air Resources Field Research Office, Las Vegas, Nevada (United States)

    1967-07-01

    A single air molecule can have a trajectory that can be described with a line, but most meteorologists use single lines to represent the trajectories of air parcels. A single line trajectory has the disadvantage that it is a categorical description of position. Like categorized forecasts it provides no qualification, and no provision for dispersion in case the parcel contains two or more molecules which may take vastly different paths. Diffusion technology has amply demonstrated that an initial aerosol cloud or volume of gas in the atmosphere not only grows larger, but sometimes divides into puffs, each having a different path or swath. Yet, the average meteorologist, faced with the problem of predicting the future motion of a cloud, usually falls back on the line trajectory approach with the explanation that he had no better tool for long range application. In his more rational moments, he may use some arbitrary device to spread his cloud with distance. One such technique has been to separate the trajectory into two or more trajectories, spaced about the endpoint of the original trajectory after a short period of travel, repeating this every so often like a chain reaction. This has the obvious disadvantage of involving a large amount of labor without much assurance of improved accuracy. Another approach is to draw a circle about the trajectory endpoint, to represent either diffusion or error. The problem then is to know what radius to give the circle and also whether to call it diffusion or error. Meteorologists at the Nevada Test Site (NTS) are asked frequently to provide advice which involves trajectory technology, such as prediction of an aerosol cloud path, reconstruction of the motion of a volume of air, indication of the dilution, and the possible trajectory prediction error over great distances. Therefore, we set out, nearly three years ago, to provide some statistical knowledge about the status of our trajectory technology. This report contains some of the

  13. Trajectories of Social Withdrawal from Middle Childhood to Early Adolescence

    Science.gov (United States)

    Oh, Wonjung; Rubin, Kenneth H.; Bowker, Julie C.; Booth-LaForce, Cathryn; Rose-Krasnor, Linda; Laursen, Brett

    2008-01-01

    Heterogeneity and individual differences in the developmental course of social withdrawal were examined longitudinally in a community sample (N = 392). General Growth Mixture Modeling (GGMM) was used to identify distinct pathways of social withdrawal, differentiate valid subgroup trajectories, and examine factors that predicted change in…

  14. Understanding adolescent personality pathology from growth trajectories of childhood oddity

    NARCIS (Netherlands)

    De Clercq, Barbara; Verbeke, Lize; De Caluwe, E.A.L.; Vercruysse, Tom; Hofmans, Joeri

    2017-01-01

    Research on developmental trajectories of early maladaptive features for understanding later personality disorders (PDs) is increasingly recognized as an important study area. The course of early odd features is highly relevant in this regard, as only a few researchers have addressed childhood

  15. Young Children's Understandings of Length Measurement: Evaluating a Learning Trajectory

    Science.gov (United States)

    Szilagyi, Janka; Clements, Douglas H.; Sarama, Julie

    2013-01-01

    This study investigated the development of length measurement ideas in students from prekindergarten through 2nd grade. The main purpose was to evaluate and elaborate the developmental progression, or levels of thinking, of a hypothesized learning trajectory for length measurement to ensure that the sequence of levels of thinking is consistent…

  16. Parent-child relationship trajectories during adolescence: Longitudinal associations with romantic outcomes in emerging adulthood

    NARCIS (Netherlands)

    Seiffge-Krenke, I.; Overbeek, G.J.; Vermulst, A.A.

    2010-01-01

    This study examined the developmental trajectories of parent-child relationships in adolescence. especially with respect to changes in support levels and negativity, and analyzed if and how these trajectories were associated with the subsequent quality of romantic relationships in young adulthood. A

  17. Trajectories of Social Anxiety during Adolescence and Relations with Cognition, Social Competence, and Temperament

    Science.gov (United States)

    Miers, A. C.; Blote, A. W.; de Rooij, M.; Bokhorst, C. L.; Westenberg, P. M.

    2013-01-01

    This cohort-sequential study examined developmental trajectories of social anxiety in a nonclinical sample (N = 331, 161 girls) aged 9 to 17 years at initial and 12 to 21 years at final assessment. We tested whether variables assessing cognition, social competence, and temperament discriminated between the trajectories. Variables were collected…

  18. Longitudinal Trajectories of Ethnic Identity among Urban Black and Latino Adolescents

    Science.gov (United States)

    Pahl, Kerstin; Way, Niobe

    2006-01-01

    The current study modeled developmental trajectories of ethnic identity exploration and affirmation and belonging from middle to late adolescence (ages 15-18) and examined how these trajectories varied according to ethnicity, gender, immigrant status, and perceived level of discrimination. The sample consisted of 135 urban low-income Black and…

  19. Automated Cooperative Trajectories

    Science.gov (United States)

    Hanson, Curt; Pahle, Joseph; Brown, Nelson

    2015-01-01

    This presentation is an overview of the Automated Cooperative Trajectories project. An introduction to the phenomena of wake vortices is given, along with a summary of past research into the possibility of extracting energy from the wake by flying close parallel trajectories. Challenges and barriers to adoption of civilian automatic wake surfing technology are identified. A hardware-in-the-loop simulation is described that will support future research. Finally, a roadmap for future research and technology transition is proposed.

  20. Branching trajectory continual integral

    International Nuclear Information System (INIS)

    Maslov, V.P.; Chebotarev, A.M.

    1980-01-01

    Heuristic definition of the Feynman continual integral over branching trajectories is suggested which makes it possible to obtain in the closed form the solution of the Cauchy problem for the model Hartree equation. A number of properties of the solution is derived from an integral representation. In particular, the quasiclassical asymptotics, exact solution in the gaussian case and perturbation theory series are described. The existence theorem for the simpliest continual integral over branching trajectories is proved [ru

  1. Developmental Scaffolding

    DEFF Research Database (Denmark)

    Giorgi, Franco; Bruni, Luis Emilio

    2015-01-01

    . Within the developmental hierarchy, each module yields an inter-level relationship that makes it possible for the scaffolding to mediate the production of selectable variations. Awide range of genetic, cellular and morphological mechanisms allows the scaffolding to integrate these modular variations...... to the complexity of sign recognition proper of a cellular community. In this semiotic perspective, the apparent goal directness of any developmental strategy should no longer be accounted for by a predetermined genetic program, but by the gradual definition of the relationships selected amongst the ones...

  2. Developmental delay

    Science.gov (United States)

    Nutrition support is essential for the care of the child with developmental delay. After a thorough evaluation, an individualized intervention plan that accounts for the child’s nutrition status, feeding ability, and medical condition may be determined. Nutrition assessments may be performed at leas...

  3. Developmental Work

    DEFF Research Database (Denmark)

    Møller, Niels; Hvid, Helge; Kristensen, Tage Søndergaard

    2003-01-01

    Human Deveoplment and Working Life - Work for Welfare explores whether the development of human resources at company level can improve individuals' quality of life, companies' possibilities of development, and welfare and democracy in society. Chapter two discuss the concept "developmental work...

  4. Gender differences in trajectories of relational aggression perpetration and victimization from middle to high school.

    Science.gov (United States)

    Orpinas, Pamela; McNicholas, Caroline; Nahapetyan, Lusine

    2015-01-01

    Relational aggression refers to harming others through damaging or manipulating peer relationships. In a cohort of students surveyed annually from middle to high school, this study identified groups of adolescents who followed distinct trajectories of perpetration and of victimization of relational aggression, compared the proportion of boys and girls in each trajectory, and examined the overlap between perpetration and victimization trajectories. The sample consisted of 620 randomly selected sixth graders. Students completed yearly surveys from Grade 6-12. We used group-based trajectory modeling to identify the trajectories. Adolescents followed three developmental trajectories of perpetration and three similar trajectories of victimization: Low (lowest aggression), Moderate, and High Declining (high in middle school, with a steep decline in high school). All trajectories declined from Grade 6-12. The largest groups were the Low perpetration (55%) and Low victimization (48%). Relational aggression trajectories differed by gender: more boys reported perpetration, and more girls reported victimization. For perpetration, slightly more boys than girls were classified in the two trajectories of higher aggression. For victimization, significantly fewer girls than boys were classified in the Low trajectory, and significantly more girls than boys were classified in the Moderate trajectory. There was substantial overlap of the perpetration and victimization trajectories. These findings highlight the importance of implementing programs to reduce relational aggression for boys and for girls. © 2014 Wiley Periodicals, Inc.

  5. Functional Trajectories, Cognition, and Subclinical Cerebrovascular Disease.

    Science.gov (United States)

    Dhamoon, Mandip S; Cheung, Ying-Kuen; Gutierrez, Jose; Moon, Yeseon P; Sacco, Ralph L; Elkind, Mitchell S V; Wright, Clinton B

    2018-03-01

    Cognition and education influence functional trajectories, but whether associations differ with subclinical brain infarcts (SBI) or white matter hyperintensity volume (WMHV) is unknown. We hypothesized that SBI and WMHV moderated relationships between cognitive performance and education and functional trajectories. A total of 1290 stroke-free individuals underwent brain magnetic resonance imaging and were followed for 7.3 years (mean) with annual functional assessments with the Barthel index (range, 0-100). Magnetic resonance imaging measurements included pathology-informed SBI (PI-SBI) and WMHV (% total cranial volume). Generalized estimating equation models tested associations between magnetic resonance imaging variables and baseline Barthel index and change in Barthel index, adjusting for demographic, vascular, cognitive, and social risk factors, and stroke and myocardial infarction during follow-up. We tested interactions among education level, baseline cognitive performance (Mini-Mental State score), and functional trajectories and ran models stratified by levels of magnetic resonance imaging variables. Mean age was 70.6 (SD, 9.0) years; 19% had PI-SBI, and mean WMHV was 0.68%. Education did not modify associations between cognition and functional trajectories. PI-SBI modified associations between cognition and functional trajectories ( P =0.04) with a significant protective effect of better cognition on functional decline seen only in those without PI-SBI. There was no significant interaction for WMHV ( P =0.8). PI-SBI, and greater WMHV, were associated with 2- to 3-fold steeper functional decline, holding cognition constant. PI-SBI moderated the association between cognition and functional trajectories, with 3-fold greater decline among those with PI-SBI (compared with no PI-SBI) and normal baseline cognition. This highlights the strong and independent association between subclinical markers and patient-centered trajectories over time. © 2018 American Heart

  6. Trajectories of BMI change impact glucose and insulin metabolism.

    Science.gov (United States)

    Walsh, E I; Shaw, J; Cherbuin, N

    2018-03-01

    The aim of this study was to examine, in a community setting, whether trajectory of weight change over twelve years is associated with glucose and insulin metabolism at twelve years. Participants were 532 community-living middle-aged and elderly adults from the Personality and Total Health (PATH) Through Life study. They spanned the full weight range (underweight/normal/overweight/obese). Latent class analysis and multivariate generalised linear models were used to investigate the association of Body Mass Index (BMI, kg/m 2 ) trajectory over twelve years with plasma insulin (μlU/ml), plasma glucose (mmol/L), and HOMA2 insulin resistance and beta cell function at follow-up. All models were adjusted for age, gender, hypertension, pre-clinical diabetes status (normal fasting glucose or impaired fasting glucose) and physical activity. Four weight trajectories were extracted; constant normal (mean baseline BMI = 25; follow-up BMI = 25), constant high (mean baseline BMI = 36; follow-up BMI = 37), increase (mean baseline BMI = 26; follow-up BMI = 32) and decrease (mean baseline BMI = 34; follow-up BMI = 28). At any given current BMI, individuals in the constant high and increase trajectories had significantly higher plasma insulin, greater insulin resistance, and higher beta cell function than those in the constant normal trajectory. Individuals in the decrease trajectory did not differ from the constant normal trajectory. Current BMI significantly interacted with preceding BMI trajectory in its association with plasma insulin, insulin resistance, and beta cell function. The trajectory of preceding weight has an independent effect on blood glucose metabolism beyond body weight measured at any given point in time. Copyright © 2017 The Italian Society of Diabetology, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition, and the Department of Clinical Medicine and Surgery, Federico II University. Published by Elsevier

  7. Attentional networks in developmental dyscalculia

    Directory of Open Access Journals (Sweden)

    Henik Avishai

    2010-01-01

    Full Text Available Abstract Background Very little is known about attention deficits in developmental dyscalculia, hence, this study was designed to provide the missing information. We examined attention abilities of participants suffering from developmental dyscalculia using the attention networks test - interactions. This test was designed to examine three different attention networks--executive function, orienting and alerting--and the interactions between them. Methods Fourteen university students that were diagnosed as suffering from developmental dyscalculia--intelligence and reading abilities in the normal range and no indication of attention-deficit hyperactivity disorder--and 14 matched controls were tested using the attention networks test - interactions. All participants were given preliminary tests to measure mathematical abilities, reading, attention and intelligence. Results The results revealed deficits in the alerting network--a larger alerting effect--and in the executive function networks--a larger congruity effect in developmental dyscalculia participants. The interaction between the alerting and executive function networks was also modulated by group. In addition, developmental dyscalculia participants were slower to respond in the non-cued conditions. Conclusions These results imply specific attentional deficits in pure developmental dyscalculia. Namely, those with developmental dyscalculia seem to be deficient in the executive function and alertness networks. They suffer from difficulty in recruiting attention, in addition to the deficits in numerical processing.

  8. Attentional networks in developmental dyscalculia.

    Science.gov (United States)

    Askenazi, Sarit; Henik, Avishai

    2010-01-07

    Very little is known about attention deficits in developmental dyscalculia, hence, this study was designed to provide the missing information. We examined attention abilities of participants suffering from developmental dyscalculia using the attention networks test - interactions. This test was designed to examine three different attention networks--executive function, orienting and alerting--and the interactions between them. Fourteen university students that were diagnosed as suffering from developmental dyscalculia--intelligence and reading abilities in the normal range and no indication of attention-deficit hyperactivity disorder--and 14 matched controls were tested using the attention networks test-interactions. All participants were given preliminary tests to measure mathematical abilities, reading, attention and intelligence. The results revealed deficits in the alerting network--a larger alerting effect--and in the executive function networks--a larger congruity effect in developmental dyscalculia participants. The interaction between the alerting and executive function networks was also modulated by group. In addition, developmental dyscalculia participants were slower to respond in the non-cued conditions. These results imply specific attentional deficits in pure developmental dyscalculia. Namely, those with developmental dyscalculia seem to be deficient in the executive function and alertness networks. They suffer from difficulty in recruiting attention, in addition to the deficits in numerical processing.

  9. Interpreting Early Career Trajectories

    Science.gov (United States)

    Barnatt, Joan; Gahlsdorf Terrell, Dianna; D'Souza, Lisa Andries; Jong, Cindy; Cochran-Smith, Marilyn; Viesca, Kara Mitchell; Gleeson, Ann Marie; McQuillan, Patrick; Shakman, Karen

    2017-01-01

    Career decisions of four teachers are explored through the concept of figured worlds in this qualitative, longitudinal case study. Participants were purposefully chosen for similarity at entry, with a range of career trajectories over time. Teacher career paths included remaining in one school, repeated changes in schools, attrition after…

  10. Trajectory structures and transport

    International Nuclear Information System (INIS)

    Vlad, Madalina; Spineanu, Florin

    2004-01-01

    The special problem of transport in two-dimensional divergence-free stochastic velocity fields is studied by developing a statistical approach, the nested subensemble method. The nonlinear process of trapping determined by such fields generates trajectory structures whose statistical characteristics are determined. These structures strongly influence the transport

  11. Increased deficit of visual attention span with development in Chinese children with developmental dyslexia.

    Science.gov (United States)

    Zhao, Jing; Liu, Menglian; Liu, Hanlong; Huang, Chen

    2018-02-16

    It has been suggested that orthographic transparency and age changes may affect the relationship between visual attention span (VAS) deficit and reading difficulty. The present study explored the developmental trend of VAS in children with developmental dyslexia (DD) in Chinese, a logographic language with a deep orthography. Fifty-seven Chinese children with DD and fifty-four age-matched normal readers participated. The visual 1-back task was adopted to examine VAS. Phonological and morphological awareness tests, and reading tests in single-character and sentence levels were used for reading skill measurements. Results showed that only high graders with dyslexia exhibited lower accuracy than the controls in the VAS task, revealing an increased VAS deficit with development in the dyslexics. Moreover, the developmental trajectory analyses demonstrated that the dyslexics seemed to exhibit an atypical but not delayed pattern in their VAS development as compared to the controls. A correlation analysis indicated that VAS was only associated with morphological awareness for dyslexic readers in high grades. Further regression analysis showed that VAS skills and morphological awareness made separate and significant contributions to single-character reading for high grader with dyslexia. These findings suggested a developmental increasing trend in the relationship between VAS skills and reading (dis)ability in Chinese.

  12. Trajectory grouping structure

    Directory of Open Access Journals (Sweden)

    Maike Buchin

    2015-03-01

    Full Text Available The collective motion of a set of moving entities like people, birds, or other animals, is characterized by groups arising, merging, splitting, and ending. Given the trajectories of these entities, we define and model a structure that captures all of such changes using the Reeb graph, a concept from topology. The trajectory grouping structure has three natural parameters that allow more global views of the data in group size, group duration, and entity inter-distance. We prove complexity bounds on the maximum number of maximal groups that can be present, and give algorithms to compute the grouping structure efficiently. We also study how the trajectory grouping structure can be made robust, that is, how brief interruptions of groups can be disregarded in the global structure, adding a notion of persistence to the structure. Furthermore, we showcase the results of experiments using data generated by the NetLogo flocking model and from the Starkey project. The Starkey data describe the movement of elk, deer, and cattle. Although there is no ground truth for the grouping structure in this data, the experiments show that the trajectory grouping structure is plausible and has the desired effects when changing the essential parameters. Our research provides the first complete study of trajectory group evolvement, including combinatorial,algorithmic, and experimental results.

  13. Gender differences in the developmental trajectories, risk factors ...

    African Journals Online (AJOL)

    Research suggests that neonatal insults were found to be better predictors of male antisocial behaviors relative to females. Research also suggests that neurocognitive differences (e.g., ADHD) were more predictive of antisocial behaviors in males than in females. Social factors (i.e., family-related and peer related) were ...

  14. Developmental Trajectories of Bullying and Social Dominance in Youth

    Science.gov (United States)

    Reijntjes, Albert; Vermande, Marjolijn; Goossens, Frits A.; Olthof, Tjeert; van de Schoot, Rens; Aleva, Liesbeth; van der Meulen, Matty

    2013-01-01

    Objective: Bullying is increasingly conceptualized as strategic behavior motivated by a desire to gain social dominance in the peer group. Cross-sectional research has shown that relative to their peers bullies are higher in social dominance as indexed by resource control, and are often perceived as powerful and "cool." However, research examining…

  15. Comparative developmental trajectory of four strains of chicken ...

    African Journals Online (AJOL)

    This study evaluated egg traits, embryonic growth, and early growth rate in four strains of chicken. A total of 1200 hatching eggs, 300 each from four strains of chicken were used for this study. The strains included Nigerian indigenous chicken (NIC), Arbor acre, Hubbard, and Marshall broiler strains. Embryonic weights, yolk ...

  16. Altering the trajectory of early postnatal cortical development can lead to structural and behavioural features of autism

    Directory of Open Access Journals (Sweden)

    Chomiak Taylor

    2010-08-01

    Full Text Available Abstract Background Autism is a behaviourally defined neurodevelopmental disorder with unknown etiology. Recent studies in autistic children consistently point to neuropathological and functional abnormalities in the temporal association cortex (TeA and its associated structures. It has been proposed that the trajectory of postnatal development in these regions may undergo accelerated maturational alterations that predominantly affect sensory recognition and social interaction. Indeed, the temporal association regions that are important for sensory recognition and social interaction are one of the last regions to mature suggesting a potential vulnerability to early maturation. However, direct evaluation of the emerging hypothesis that an altered time course of early postnatal development can lead to an ASD phenotype remains lacking. Results We used electrophysiological, histological, and behavioural techniques to investigate if the known neuronal maturational promoter valproate, similar to that in culture systems, can influence the normal developmental trajectory of TeA in vivo. Brain sections obtained from postnatal rat pups treated with VPA in vivo revealed that almost 40% of cortical cells in TeA prematurely exhibited adult-like intrinsic electrophysiological properties and that this was often associated with gross cortical hypertrophy and a reduced predisposition for social play behaviour. Conclusions The co-manifestation of these functional, structural and behavioural features suggests that alteration of the developmental time course in certain high-order cortical networks may play an important role in the neurophysiological basis of autism.

  17. Semantic Enrichment of GPS Trajectories

    NARCIS (Netherlands)

    de Graaff, V.; van Keulen, Maurice; de By, R.A.

    2012-01-01

    Semantic annotation of GPS trajectories helps us to recognize the interests of the creator of the GPS trajectories. Automating this trajectory annotation circumvents the requirement of additional user input. To annotate the GPS traces automatically, two types of automated input are required: 1) a

  18. Microstructure, length, and connection of limbic tracts in normal human brain development

    Directory of Open Access Journals (Sweden)

    Qiaowen eYu

    2014-08-01

    Full Text Available The cingulum and fornix play an important role in memory, attention, spatial orientation and feeling functions. Both microstructure and length of these limbic tracts can be affected by mental disorders such as Alzheimer’s disease, depression, autism, anxiety, and schizophrenia. To date, there has been little systematic characterization of their microstructure, length and functional connectivity in normally developing brains. In this study, diffusion tensor imaging (DTI and resting state functional MRI (rs-fMRI data from 65 normally developing right-handed subjects from birth to young adulthood was acquired. After cingulate gyrus part of the cingulum (cgc, hippocampal part of the cingulum (cgh and fornix (fx were traced with DTI tractography, absolute and normalized tract lengths and DTI-derived metrics including fractional anisotropy, mean, axial and radial diffusivity were measured for traced limbic tracts. Free water elimination (FWE algorithm was adopted to improve accuracy of the measurements of DTI-derived metrics. The role of these limbic tracts in the functional network at birth and adulthood was explored. We found a logarithmic age-dependent trajectory for FWE-corrected DTI metric changes with fast increase of microstructural integrity from birth to 2-year-old followed by a slow increase to 25-year-old. Normalized tract length of cgc increases with age, while no significant relationship with age was found for normalized tract lengths of cgh and fx. Stronger microstructural integrity on the left side compared to that of right side was found. With integrated DTI and rs-fMRI, the key connectional role of cgc and cgh in the default mode network (DMN was confirmed as early as birth. Systematic characterization of length and DTI metrics after FWE correction of limbic tracts offers insight into their morphological and microstructural developmental trajectories. These trajectories may serve as a normal reference for pediatric patients with

  19. Electron trajectory program

    International Nuclear Information System (INIS)

    Herrmannsfeldt, W.B.

    1979-11-01

    The SLAC Electron Trajectory Program is described and instructions and examples for users are given. The program is specifically written to compute trajectories of charged particles in electrostatic and magnetostatic focusing systems including the effects of space charge and self-magnetic fields. Starting options include Child's Law conditions on cathodes of various shapes. Either rectangular or cylindrically symmetric geometry may be used. Magntic fields may be specified using arbitrary configurations of coils, or the output of a magnet program such as Poisson or by an externally calculated array of the axial fields. The program is available in IBM FORTRAN but can be easily converted for use on other brands of hardware. The program is intended to be used with a plotter whose interface the user must provide

  20. Electron trajectory program

    Energy Technology Data Exchange (ETDEWEB)

    Herrmannsfeldt, W.B.

    1979-11-01

    The SLAC Electron Trajectory Program is described and instructions and examples for users are given. The program is specifically written to compute trajectories of charged particles in electrostatic and magnetostatic focusing systems including the effects of space charge and self-magnetic fields. Starting options include Child's Law conditions on cathodes of various shapes. Either rectangular or cylindrically symmetric geometry may be used. Magntic fields may be specified using arbitrary configurations of coils, or the output of a magnet program such as Poisson or by an externally calculated array of the axial fields. The program is available in IBM FORTRAN but can be easily converted for use on other brands of hardware. The program is intended to be used with a plotter whose interface the user must provide.

  1. Au pair trajectories

    DEFF Research Database (Denmark)

    Dalgas, Karina Märcher

    2015-01-01

    pair-sending families in the Philippines, this dissertation examines the long-term trajectories of these young Filipinas. It shows how the au pairs’ local and transnational family relations develop over time and greatly influence their life trajectories. A focal point of the study is how au pairs...... that Filipina au pairs see their stay abroad as an avenue of personal development and social recognition, I examine how the au pairs re-position themselves within their families at home through migration, and how they navigate between the often conflicting expectations of participation in the sociality......Since 2000, thousands of young Filipino migrants have come to Denmark as au pairs. Officially, they are there to “broaden their cultural horizons” by living temporarily with a Danish host family, but they also conduct domestic labor in exchange for food and money, which allows them to send...

  2. Longer Exposure to Obesity, Slimmer Chance of College? Body Weight Trajectories, Non-Cognitive Skills, and College Completion

    Science.gov (United States)

    Cheng, Yen-hsin Alice

    2017-01-01

    The NLSY97 data were used to explore the patterns of developmental trajectories of body weight in adolescence and how they affected the likelihood of college completion in young adulthood among 2,275 youths aged 13 and 14 in Wave 1. A strong weight trajectory gradient was found for rates of college completion. The study further explored the role…

  3. Trajectories of Physical Dating Violence from Middle to High School: Association with Relationship Quality and Acceptability of Aggression

    Science.gov (United States)

    Orpinas, Pamela; Hsieh, Hsien-Lin; Song, Xiao; Holland, Kristin; Nahapetyan, Lusine

    2013-01-01

    Although research on dating violence is growing, little is known about the distinct developmental trajectories of dating violence during adolescence. The current study identifies trajectories of physical dating violence victimization and perpetration that boys and girls follow from sixth to twelfth grade, examines the overlap of these…

  4. SWIMMING BEHAVIOR OF DEVELOPMENTAL STAGES OF THE CALANOID COPEPOD TEMORA-LONGICORNIS AT DIFFERENT FOOD CONCENTRATIONS

    NARCIS (Netherlands)

    VANDUREN, LA; VIDELER, JJ

    1995-01-01

    The swimming behaviour of developmental stages of the marine calanoid copepod Temora longicornis was studied using 2-dimensional observations under a microscope and a 3-dimensional filming technique to analyze swimming mode, swimming speed and swimming trajectories under different food

  5. Trajectory Shape Analysis and Anomaly Detection Utilizing Information Theory Tools

    Directory of Open Access Journals (Sweden)

    Yuejun Guo

    2017-06-01

    Full Text Available In this paper, we propose to improve trajectory shape analysis by explicitly considering the speed attribute of trajectory data, and to successfully achieve anomaly detection. The shape of object motion trajectory is modeled using Kernel Density Estimation (KDE, making use of both the angle attribute of the trajectory and the speed of the moving object. An unsupervised clustering algorithm, based on the Information Bottleneck (IB method, is employed for trajectory learning to obtain an adaptive number of trajectory clusters through maximizing the Mutual Information (MI between the clustering result and a feature set of the trajectory data. Furthermore, we propose to effectively enhance the performance of IB by taking into account the clustering quality in each iteration of the clustering procedure. The trajectories are determined as either abnormal (infrequently observed or normal by a measure based on Shannon entropy. Extensive tests on real-world and synthetic data show that the proposed technique behaves very well and outperforms the state-of-the-art methods.

  6. Exploring Trajectories of Pornography Use Through Adolescence and Emerging Adulthood.

    Science.gov (United States)

    Willoughby, Brian J; Young-Petersen, Bonnie; Leonhardt, Nathan D

    2018-01-01

    While the scholarly literature on pornography use is growing, much of this literature has examined pornography use as a static feature that does not change. Despite this trend, pornography use, like most sexual behaviors, is likely best viewed as a dynamic feature that may shift across the developmental life span. Using a sample of 908 adults from the United States, retrospective data on pornography use through adolescence and emerging adulthood were gathered to explore trajectories of pornography use across these developmental periods. Latent mixture models suggested the presence of common patterns of use across both developmental periods. Adolescence patterns appeared to largely be distinguished by those who either engaged or did not engage with pornography, while emerging adulthood data revealed the presence of a group of experimenters who engaged in pornography through adolescence but then decreased use through their 20s. Men were found to be more likely to have consistent profiles of pornography use, while single adults were likely to have delayed entry into pornography use. Associations with adult mental health and pornography use were found, suggesting that early exposure to pornography was related to elevated current pornography use patterns and, to a lesser extent, dysfunctional pornography use. Trajectories also had a weak association with life satisfaction, with individuals reporting trajectories involving consistent pornography use reporting lower life satisfaction after controls.

  7. The Longitudinal Interplay of Adolescents' Self-Esteem and Body Image: A Conditional Autoregressive Latent Trajectory Analysis

    Science.gov (United States)

    Morin, Alexandre J. S.; Maiano, Christophe; Marsh, Herbert W.; Janosz, Michel; Nagengast, Benjamin

    2011-01-01

    Self-esteem and body image are central to coping successfully with the developmental challenges of adolescence. However, the current knowledge surrounding self-esteem and body image is fraught with controversy. This study attempts to clarify some of them by addressing three questions: (1) Are the intraindividual developmental trajectories of…

  8. Developmental dyscalculia.

    Science.gov (United States)

    Kucian, Karin; von Aster, Michael

    2015-01-01

    Numerical skills are essential in our everyday life, and impairments in the development of number processing and calculation have a negative impact on schooling and professional careers. Approximately 3 to 6 % of children are affected from specific disorders of numerical understanding (developmental dyscalculia (DD)). Impaired development of number processing skills in these children is characterized by problems in various aspects of numeracy as well as alterations of brain activation and brain structure. Moreover, DD is assumed to be a very heterogeneous disorder putting special challenges to define homogeneous diagnostic criteria. Finally, interdisciplinary perspectives from psychology, neuroscience and education can contribute to the design for interventions, and although results are still sparse, they are promising and have shown positive effects on behaviour as well as brain function. In the current review, we are going to give an overview about typical and atypical development of numerical abilities at the behavioural and neuronal level. Furthermore, current status and obstacles in the definition and diagnostics of DD are discussed, and finally, relevant points that should be considered to make an intervention as successful as possible are summarized.

  9. Moyal dynamics and trajectories

    Science.gov (United States)

    Braunss, G.

    2010-01-01

    We give first an approximation of the operator δh: f → δhf := h*planckf - f*planckh in terms of planck2n, n >= 0, where h\\equiv h(p,q), (p,q)\\in {\\mathbb R}^{2 n} , is a Hamilton function and *planck denotes the star product. The operator, which is the generator of time translations in a *planck-algebra, can be considered as a canonical extension of the Liouville operator Lh: f → Lhf := {h, f}Poisson. Using this operator we investigate the dynamics and trajectories of some examples with a scheme that extends the Hamilton-Jacobi method for classical dynamics to Moyal dynamics. The examples we have chosen are Hamiltonians with a one-dimensional quartic potential and two-dimensional radially symmetric nonrelativistic and relativistic Coulomb potentials, and the Hamiltonian for a Schwarzschild metric. We further state a conjecture concerning an extension of the Bohr-Sommerfeld formula for the calculation of the exact eigenvalues for systems with classically periodic trajectories.

  10. Repetitive Rockfall Trajectory Testing

    Directory of Open Access Journals (Sweden)

    Axel Volkwein

    2018-03-01

    Full Text Available Numerical simulations of rockfall trajectories are a standard procedure for evaluating rockfall hazards. For these simulations, corresponding software codes must be calibrated and evaluated based on field data. This study addresses methods of repeatable rockfall tests, and investigates whether it is possible to produce traceable and statistically analysable data. A testing series is described extensively covering how to conduct rockfall experiments and how certain elements of rockfall trajectories can be measured. The tests use acceleration and rotation sensors inside test blocks, a system to determine block positions over time, surveying measurements, and video recordings. All systems are evaluated regarding their usability in the field and for analyses. The highly detailed description of testing methods is the basis for sound understanding and reproducibility of the tests. This article serves as a reference for future publications and other rockfall field tests, both as a guide and as a basis for comparisons. First analyses deliver information on runout with a shadow angle ranging between 21 and 45 degrees for a slope consisting of homogeneous soft soil. A digital elevation model of the test site as well as point clouds of the used test blocks are part of this publication.

  11. Canonical transformations of Kepler trajectories

    International Nuclear Information System (INIS)

    Mostowski, Jan

    2010-01-01

    In this paper, canonical transformations generated by constants of motion in the case of the Kepler problem are discussed. It is shown that canonical transformations generated by angular momentum are rotations of the trajectory. Particular attention is paid to canonical transformations generated by the Runge-Lenz vector. It is shown that these transformations change the eccentricity of the orbit. A method of obtaining elliptic trajectories from the circular ones with the help of canonical trajectories is discussed.

  12. Clarifying Normalization

    Science.gov (United States)

    Carpenter, Donald A.

    2008-01-01

    Confusion exists among database textbooks as to the goal of normalization as well as to which normal form a designer should aspire. This article discusses such discrepancies with the intention of simplifying normalization for both teacher and student. This author's industry and classroom experiences indicate such simplification yields quicker…

  13. Maternal age and trajectories of cannabis use.

    Science.gov (United States)

    De Genna, Natacha M; Cornelius, Marie D; Goldschmidt, Lidush; Day, Nancy L

    2015-11-01

    Becoming a mother is a developmental transition that has been linked to desistance from substance use. However, timing of motherhood may be a key determinant of cannabis use in women, based on preliminary evidence from teenage mothers. The goal of this study was to identify trajectories of maternal cannabis use, and to determine if maternal age was associated with different trajectories of use. This prospective study examined 456 pregnant women recruited at a prenatal clinic, ranging in age from 13 to 42 years. The women were interviewed about their cannabis use 1 year prior to pregnancy and during each trimester of pregnancy, and at 6, 10, 14, and 16 years post-partum. A growth mixture model of cannabis use reported at each time point clearly delineated four groups: non/unlikely to use, decreasing likelihood of use, late desistance, and increasing likelihood/chronic use (Lo-Mendell-Rubin adjusted LRT test statistic=35.7, pdepressive symptoms were also associated with more frequent use. These findings have implications for both prevention and treatment of cannabis use in mothers. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  14. Trajectory Based Traffic Analysis

    DEFF Research Database (Denmark)

    Krogh, Benjamin Bjerre; Andersen, Ove; Lewis-Kelham, Edwin

    2013-01-01

    We present the INTRA system for interactive path-based traffic analysis. The analyses are developed in collaboration with traffic researchers and provide novel insights into conditions such as congestion, travel-time, choice of route, and traffic-flow. INTRA supports interactive point-and-click a......We present the INTRA system for interactive path-based traffic analysis. The analyses are developed in collaboration with traffic researchers and provide novel insights into conditions such as congestion, travel-time, choice of route, and traffic-flow. INTRA supports interactive point......-and-click analysis, due to a novel and efficient indexing structure. With the web-site daisy.aau.dk/its/spqdemo/we will demonstrate several analyses, using a very large real-world data set consisting of 1.9 billion GPS records (1.5 million trajectories) recorded from more than 13000 vehicles, and touching most...

  15. Urban water trajectories

    CERN Document Server

    Allen, Adriana; Hofmann, Pascale; Teh, Tse-Hui

    2017-01-01

    Water is an essential element in the future of cities. It shapes cities’ locations, form, ecology, prosperity and health. The changing nature of urbanisation, climate change, water scarcity, environmental values, globalisation and social justice mean that the models of provision of water services and infrastructure that have dominated for the past two centuries are increasingly infeasible. Conventional arrangements for understanding and managing water in cities are being subverted by a range of natural, technological, political, economic and social changes. The prognosis for water in cities remains unclear, and multiple visions and discourses are emerging to fill the space left by the certainty of nineteenth century urban water planning and engineering. This book documents a sample of those different trajectories, in terms of water transformations, option, services and politics. Water is a key element shaping urban form, economies and lifestyles, part of the ongoing transformation of cities. Cities are face...

  16. Dissociation between face perception and face memory in adults, but not children, with developmental prosopagnosia.

    Science.gov (United States)

    Dalrymple, Kirsten A; Garrido, Lúcia; Duchaine, Brad

    2014-10-01

    Cognitive models propose that face recognition is accomplished through a series of discrete stages, including perceptual representation of facial structure, and encoding and retrieval of facial information. This implies that impaired face recognition can result from failures of face perception, face memory, or both. Studies of acquired prosopagnosia, autism spectrum disorders, and the development of normal face recognition support the idea that face perception and face memory are distinct processes, yet this distinction has received little attention in developmental prosopagnosia (DP). To address this issue, we tested the face perception and face memory of children and adults with DP. By definition, face memory is impaired in DP, so memory deficits were present in all participants. However, we found that all children, but only half of the adults had impaired face perception. Thus, results from adults indicate that face perception and face memory are dissociable, while the results from children provide no evidence for this division. Importantly, our findings raise the possibility that DP is qualitatively different in childhood versus adulthood. We discuss theoretical explanations for this developmental pattern and conclude that longitudinal studies are necessary to better understand the developmental trajectory of face perception and face memory deficits in DP. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  17. Dissociation between face perception and face memory in adults, but not children, with developmental prosopagnosia

    Directory of Open Access Journals (Sweden)

    Kirsten A. Dalrymple

    2014-10-01

    Full Text Available Cognitive models propose that face recognition is accomplished through a series of discrete stages, including perceptual representation of facial structure, and encoding and retrieval of facial information. This implies that impaired face recognition can result from failures of face perception, face memory, or both. Studies of acquired prosopagnosia, autism spectrum disorders, and the development of normal face recognition support the idea that face perception and face memory are distinct processes, yet this distinction has received little attention in developmental prosopagnosia (DP. To address this issue, we tested the face perception and face memory of children and adults with DP. By definition, face memory is impaired in DP, so memory deficits were present in all participants. However, we found that all children, but only half of the adults had impaired face perception. Thus, results from adults indicate that face perception and face memory are dissociable, while the results from children provide no evidence for this division. Importantly, our findings raise the possibility that DP is qualitatively different in childhood versus adulthood. We discuss theoretical explanations for this developmental pattern and conclude that longitudinal studies are necessary to better understand the developmental trajectory of face perception and face memory deficits in DP.

  18. Toward Developmental Connectomics of the Human Brain

    OpenAIRE

    Cao, Miao; Huang, Hao; Peng, Yun; Dong, Qi; He, Yong

    2016-01-01

    Imaging connectomics based on graph theory has become an effective and unique methodological framework for studying structural and functional connectivity patterns of the developing brain. Normal brain development is characterized by continuous and significant network evolution throughout infancy, childhood, and adolescence, following specific maturational patterns. Disruption of these normal changes is associated with neuropsychiatric developmental disorders, such as autism spectrum disorder...

  19. Towards Developmental Connectomics of the Human Brain

    OpenAIRE

    Miao eCao; Hao eHuang; Hao eHuang; Yun ePeng; Qi eDong; Yong eHe

    2016-01-01

    Imaging connectomics based on graph theory has become an effective and unique methodological framework for studying structural and functional connectivity patterns of the developing brain. Normal brain development is characterized by continuous and significant network evolution throughout infancy, childhood and adolescence, following specific maturational patterns. Disruption of these normal changes is associated with neuropsychiatric developmental disorders, such as autism spectrum disorders...

  20. The Developmental Sequence of Social-Communicative Skills in Young Children with Autism: A Longitudinal Study

    Science.gov (United States)

    Wu, Chin-Chin; Chiang, Chung-Hsin

    2014-01-01

    To explore the different developmental trajectories of social-communicative skills in children with autism and typically developing infants, two longitudinal studies were conducted. In Study 1, we examined the developmental sequence of social-communicative skills in 26 typically developing infants when they were 9 months old and reexamined them…

  1. Developmental Risk and Young Children's Regulatory Strategies: Predicting Behavior Problems at Age Five

    Science.gov (United States)

    Gerstein, Emily D.; Pedersen y Arbona, Anita; Crnic, Keith A.; Ryu, Ehri; Baker, Bruce L.; Blacher, Jan

    2011-01-01

    Children with early developmental delays are at heightened risk for behavior problems and comorbid psychopathology. This study examined the trajectories of regulatory capabilities and their potentially mediating role in the development of behavior problems for children with and without early developmental delays. A sample of 231 children comprised…

  2. Connection-based and object-based grouping in multiple-object tracking: A developmental study

    NARCIS (Netherlands)

    R.E.R. van der Hallen (Ruth); Reusens, J. (Julie); Evers, K. (Kris); L. de-Wit (Lee); J. Wagemans (Johan)

    2018-01-01

    textabstractDevelopmental research on Gestalt laws has previously revealed that, even as young as infancy, we are bound to group visual elements into unitary structures in accordance with a variety of organizational principles. Here, we focus on the developmental trajectory of both connection-based

  3. Developmental programming of happiness.

    Science.gov (United States)

    Schmidt, Louis A; Fortier, Paz; Lahat, Ayelet; Tang, Alva; Mathewson, Karen J; Saigal, Saroj; Boyle, Michael H; Van Lieshout, Ryan J

    2017-09-01

    Being born at an extremely low birth weight (ELBW; programming hypotheses. Interfacing prenatal programming and differential susceptibility hypotheses, we tested whether individuals with ELBW in different childhood rearing environments showed different attention biases to positive and negative facial emotions in adulthood. Using the oldest known, prospectively followed cohort of ELBW survivors, we found that relative to normal birth weight controls (NBW; >2,500 grams), ELBW survivors displayed the highest and lowest attention bias to happy faces at age 30-35, depending on whether their total family income at age 8 was relatively low (environmental match) or high (environmental mismatch), respectively. This bias to happy faces was associated with a reduced likelihood of emotional problems. Findings suggest that differential susceptibility to positive emotions may be prenatally programmed, with effects lasting into adulthood. We discuss implications for integrating prenatal programming and differential susceptibility hypotheses, and the developmental origins of postnatal plasticity and resilience. © 2017 Wiley Periodicals, Inc.

  4. Trajectories of Sensation Seeking Among Puerto Rican Children and Youth.

    Science.gov (United States)

    Martins, Silvia S; Wall, Melanie M; Eisenberg, Ruth; Blanco, Carlos; Santaella, Julian; Ramos-Olazagasti, Maria; Canino, Glorisa; Bird, Hector R; Brown, Qiana; Duarte, Cristiane S

    2015-12-01

    To document the natural course of sensation seeking from childhood to adolescence, characterize distinct sensation seeking trajectories, and examine how these trajectories vary according to selected predictors. Data were obtained from the Boricua Youth Study, a longitudinal study of 2,491 children and adolescents of Puerto Rican background (3 assessments from 2000 to 2004). First, age-specific sensation seeking levels were characterized, and then age-adjusted residuals were analyzed using growth mixture models. On average, sensation seeking was stable in childhood (ages 5-10 years) and increased during adolescence (ages 11-17 years). Mean scores of sensation seeking were higher in the South Bronx versus Puerto Rico and among males versus females. Four classes of sensation seeking trajectories were observed: most study participants had age-expected sensation seeking trajectories following the average for their age ("normative," 43.8%); others (37.2%) remained consistently lower than the expected average for their age ("low" sensation seeking); some (12.0%) had an "accelerated" sensation seeking trajectory, increasing at a faster rate than expected; and a minority (7.0%) had a decreasing sensation seeking trajectory that started high but decreased, reaching scores slightly higher than the age-average sensation seeking scores ("stabilizers"). Site (South Bronx versus Puerto Rico) and gender were predictors of membership in a specific class of sensation seeking trajectory. It is important to take a developmental approach when examining sensation seeking and to consider gender and the social environment when trying to understand how sensation seeking evolves during childhood and adolescence. Copyright © 2015 American Academy of Child and Adolescent Psychiatry. Published by Elsevier Inc. All rights reserved.

  5. Predictors of Latent Trajectory Classes of Dating Violence Victimization

    Science.gov (United States)

    Brooks-Russell, Ashley; Foshee, Vangie; Ennett, Susan

    2014-01-01

    This study identified classes of developmental trajectories of physical dating violence victimization from grades 8 to 12 and examined theoretically-based risk factors that distinguished among trajectory classes. Data were from a multi-wave longitudinal study spanning 8th through 12th grade (n = 2,566; 51.9% female). Growth mixture models were used to identify trajectory classes of physical dating violence victimization separately for girls and boys. Logistic and multinomial logistic regressions were used to identify situational and target vulnerability factors associated with the trajectory classes. For girls, three trajectory classes were identified: a low/non-involved class; a moderate class where victimization increased slightly until the 10th grade and then decreased through the 12th grade; and a high class where victimization started at a higher level in the 8th grade, increased substantially until the 10th grade, and then decreased until the 12th grade. For males, two classes were identified: a low/non-involved class, and a victimized class where victimization increased slightly until the 9th grade, decreased until the 11th grade, and then increased again through the 12th grade. In bivariate analyses, almost all of the situational and target vulnerability risk factors distinguished the victimization classes from the non-involved classes. However, when all risk factors and control variables were in the model, alcohol use (a situational vulnerability) was the only factor that distinguished membership in the moderate trajectory class from the non-involved class for girls; anxiety and being victimized by peers (target vulnerability factors) were the factors that distinguished the high from the non-involved classes for the girls; and victimization by peers was the only factor distinguishing the victimized from the non-involved class for boys. These findings contribute to our understanding of the heterogeneity in physical dating violence victimization during

  6. Segmenting Trajectories by Movement States

    NARCIS (Netherlands)

    Buchin, M.; Kruckenberg, H.; Kölzsch, A.; Timpf, S.; Laube, P.

    2013-01-01

    Dividing movement trajectories according to different movement states of animals has become a challenge in movement ecology, as well as in algorithm development. In this study, we revisit and extend a framework for trajectory segmentation based on spatio-temporal criteria for this purpose. We adapt

  7. Geometric Algorithms for Trajectory Analysis

    NARCIS (Netherlands)

    Staals, Frank

    2015-01-01

    Technology such as the Global Positing System (GPS) has made tracking moving entities easy and cheap. As a result there is a large amount of trajectory data available, and an increasing demand on tools and techniques to analyze such data. We consider several analysis tasks for trajectory data,

  8. Cultural Variations in Global versus Local Processing: A Developmental Perspective

    Science.gov (United States)

    Oishi, Shigehiro; Jaswal, Vikram K.; Lillard, Angeline S.; Mizokawa, Ai; Hitokoto, Hidefumi; Tsutsui, Yoshiro

    2014-01-01

    We conducted 3 studies to explore cultural differences in global versus local processing and their developmental trajectories. In Study 1 ("N" = 363), we found that Japanese college students were less globally oriented in their processing than American or Argentine participants. We replicated this effect in Study 2 ("N" =…

  9. Future Directions in Sleep and Developmental Psychopathology.

    Science.gov (United States)

    Meltzer, Lisa J

    2017-01-01

    It is critical for psychologists to gain a better understanding about the intersection between sleep and developmental psychopathology. However, while many strive to answer the question of whether sleep causes developmental psychopathology, or vice versa, ultimately the relationship between sleep and developmental psychopathology is complex and dynamic. This article considers future directions in the field of clinical child and adolescent psychology that go beyond this mechanistic question, highlighting areas important to address for clinicians and researchers who strive to better understand how best to serve children and adolescents with developmental psychopathology. Questions are presented about what is normal in terms of sleep across development, the role of individual variability in terms of sleep needs and vulnerability to sleep loss, and how sleep may serve as a risk or resilience factor for developmental psychopathology, concluding with considerations for interventions.

  10. Lunar Cube Transfer Trajectory Options

    Science.gov (United States)

    Folta, David; Dichmann, Donald James; Clark, Pamela E.; Haapala, Amanda; Howell, Kathleen

    2015-01-01

    Numerous Earth-Moon trajectory and lunar orbit options are available for Cubesat missions. Given the limited Cubesat injection infrastructure, transfer trajectories are contingent upon the modification of an initial condition of the injected or deployed orbit. Additionally, these transfers can be restricted by the selection or designs of Cubesat subsystems such as propulsion or communication. Nonetheless, many trajectory options can b e considered which have a wide range of transfer duration, fuel requirements, and final destinations. Our investigation of potential trajectories highlights several options including deployment from low Earth orbit (LEO) geostationary transfer orbits (GTO) and higher energy direct lunar transfer and the use of longer duration Earth-Moon dynamical systems. For missions with an intended lunar orbit, much of the design process is spent optimizing a ballistic capture while other science locations such as Sun-Earth libration or heliocentric orbits may simply require a reduced Delta-V imparted at a convenient location along the trajectory.

  11. Religion and psychosis: a common evolutionary trajectory?

    Science.gov (United States)

    Dein, Simon; Littlewood, Roland

    2011-07-01

    In this article we propose that schizophrenia and religious cognition engage cognate mental modules in the over-attribution of agency and the overextension of theory of mind. We argue similarities and differences between assumptions of ultrahuman agents with omniscient minds and certain ''pathological'' forms of thinking in schizophrenia: thought insertion, withdrawal and broadcasting, and delusions of reference. In everyday religious cognition agency detection and theory of mind modules function ''normally,'' whereas in schizophrenia both modules are impaired. It is suggested that religion and schizophrenia have perhaps had a related evolutionary trajectory.

  12. Birkhoff normalization

    NARCIS (Netherlands)

    Broer, H.; Hoveijn, I.; Lunter, G.; Vegter, G.

    2003-01-01

    The Birkhoff normal form procedure is a widely used tool for approximating a Hamiltonian systems by a simpler one. This chapter starts out with an introduction to Hamiltonian mechanics, followed by an explanation of the Birkhoff normal form procedure. Finally we discuss several algorithms for

  13. Developmentalism: An Obscure but Pervasive Restriction

    Directory of Open Access Journals (Sweden)

    J. E. Stone

    1996-04-01

    Full Text Available Despite continuing criticism of public education, experimentally demonstrated and field tested teaching methods have been ignored, rejected, and abandoned. Instead of a stable consensus regarding best teaching practices, there seems only an unending succession of innovations. A longstanding educational doctrine appears to underlie this anomalous state of affairs. Termed developmentalism, it presumes "natural" ontogenesis to be optimal and it requires experimentally demonstrated teaching practices to overcome a presumption that they interfere with an optimal developmental trajectory. It also discourages teachers and parents from asserting themselves with children. Instead of effective interventions, it seeks the preservation of a postulated natural perfection. Developmentalism's rich history is expressed in a literature extending over 400 years. Its notable exponents include Jean Jacques Rousseau, John Dewey, and Jean Piaget; and its most recent expressions include "developmentally appropriate practice" and "constructivism." In the years during which it gained ascendance, developmentalism served as a basis for rejecting harsh and inhumane teaching methods. Today it impedes efforts to hold schools accountable for student academic achievement.

  14. Generic trajectory representation and trajectory following for wheeled robots

    DEFF Research Database (Denmark)

    Kjærgaard, Morten; Andersen, Nils Axel; Ravn, Ole

    2014-01-01

    will drive. Safe: Avoid fatal collisions. Based on a survey of existing methods and algorithms the article presents a generic way to represent constraints for different types of robots, a generic way to represent trajectories using Bëzier curves, a method to convert the trajectory so it can be driven...... in a smooth motion, a method to create a safe velocity profile for the robot, and a path following controller....

  15. Construction and evaluation of normalized cDNA libraries enriched with full-length sequences for rapid discovery of new genes from Sisal (Agave sisalana Perr.) different developmental stages.

    Science.gov (United States)

    Zhou, Wen-Zhao; Zhang, Yan-Mei; Lu, Jun-Ying; Li, Jun-Feng

    2012-10-12

    To provide a resource of sisal-specific expressed sequence data and facilitate this powerful approach in new gene research, the preparation of normalized cDNA libraries enriched with full-length sequences is necessary. Four libraries were produced with RNA pooled from Agave sisalana multiple tissues to increase efficiency of normalization and maximize the number of independent genes by SMART™ method and the duplex-specific nuclease (DSN). This procedure kept the proportion of full-length cDNAs in the subtracted/normalized libraries and dramatically enhanced the discovery of new genes. Sequencing of 3875 cDNA clones of libraries revealed 3320 unigenes with an average insert length about 1.2 kb, indicating that the non-redundancy of libraries was about 85.7%. These unigene functions were predicted by comparing their sequences to functional domain databases and extensively annotated with Gene Ontology (GO) terms. Comparative analysis of sisal unigenes and other plant genomes revealed that four putative MADS-box genes and knotted-like homeobox (knox) gene were obtained from a total of 1162 full-length transcripts. Furthermore, real-time PCR showed that the characteristics of their transcripts mainly depended on the tight expression regulation of a number of genes during the leaf and flower development. Analysis of individual library sequence data indicated that the pooled-tissue approach was highly effective in discovering new genes and preparing libraries for efficient deep sequencing.

  16. Low Thrust Trajectory Design for GSFC Missions

    Data.gov (United States)

    National Aeronautics and Space Administration — The Evolutionary Mission Trajectory Generator (EMTG) is a global trajectory optimization tool. EMTG is intended for use in designing interplanetary missions which...

  17. Trajectories of Attentional Development: An Exploration with the Master Activation Map Model

    Science.gov (United States)

    Michael, George A.; Lete, Bernard; Ducrot, Stephanie

    2013-01-01

    The developmental trajectories of several attention components, such as orienting, inhibition, and the guidance of selection by relevance (i.e., advance knowledge relevant to the task) were investigated in 498 participants (ages 7, 8, 9, 10, 11, and 20). The paradigm was based on Michael et al.'s (2006) master activation map model and consisted of…

  18. Parenting and Trajectories of Children's Maladaptive Behaviors: A 12-Year Prospective Community Study

    Science.gov (United States)

    Luyckx, Koen; Tildesley, Elizabeth A.; Soenens, Bart; Andrews, Judy A.; Hampson, Sarah E.; Peterson, Missy; Duriez, Bart

    2011-01-01

    This study investigated how parenting accounted for interindividual differences in developmental trajectories of different child behaviors across childhood and adolescence. In a cohort sequential community sample of 1,049 children, latent class growth analysis was applied to three parent-reported dimensions (monitoring, positive parenting,…

  19. The development of creative cognition across adolescence: distinct trajectories for insight and divergent thinking

    NARCIS (Netherlands)

    Kleibeuker, S.W.; de Dreu, C.K.W.; Crone, E.A.

    2013-01-01

    We examined developmental trajectories of creative cognition across adolescence. Participants (N = 98), divided into four age groups (12/13 yrs, 15/16 yrs, 18/19 yrs, and 25-30 yrs), were subjected to a battery of tasks gauging creative insight (visual; verbal) and divergent thinking (verbal;

  20. Trajectories of Emotional Well-Being in Mothers of Adolescents and Adults with Autism

    Science.gov (United States)

    Barker, Erin T.; Hartley, Sigan L.; Seltzer, Marsha Mailick; Floyd, Frank J.; Greenberg, Jan S.; Orsmond, Gael I.

    2011-01-01

    Raising an adolescent or adult child with a developmental disability confers exceptional care giving challenges on parents. We examined trajectories of 2 indicators of emotional well-being (depressive symptoms and anxiety) in a sample of primarily Caucasian mothers (N = 379; M[subscript age] = 51.22 years at Time 1) of adolescent and adult…

  1. Adolescents' Body Image Trajectories: A Further Test of the Self-Equilibrium Hypothesis

    Science.gov (United States)

    Morin, Alexandre J. S.; Maïano, Christophe; Scalas, L. Francesca; Janosz, Michel; Litalien, David

    2017-01-01

    The self-equilibrium hypothesis underlines the importance of having a strong core self, which is defined as a high and developmentally stable self-concept. This study tested this hypothesis in relation to body image (BI) trajectories in a sample of 1,006 adolescents (M[subscript age] = 12.6, including 541 males and 465 females) across a 4-year…

  2. Direct and interactive effects of parent, friend and schoolmate drinking on alcohol use trajectories.

    Science.gov (United States)

    Lynch, Alicia Doyle; Coley, Rebekah Levine; Sims, Jacqueline; Lombardi, Caitlin McPherran; Mahalik, James R

    2015-01-01

    This study considered the unique and interactive roles of social norms from parents, friends and schools in predicting developmental trajectories of adolescent drinking and intoxication. Using data from the National Longitudinal Study of Adolescent Health, which followed adolescents (N = 18,921) for 13 years, we used discrete mixture modelling to identify unique developmental trajectories of drinking and of intoxication. Next, multilevel multinomial regression models examined the role of alcohol-related social norms from parents, friends and schoolmates in the prediction of youths' trajectory group membership. Results demonstrated that social norms from parents, friends and schoolmates that were favourable towards alcohol use uniquely predicted drinking and intoxication trajectory group membership. Interactions between social norms revealed that schoolmate drinking played an important moderating role, frequently augmenting social norms from parents and friends. The current findings suggest that social norms from multiple sources (parents, friends and schools) work both independently and interactively to predict longitudinal trajectories of adolescent alcohol use. Results highlight the need to identify and understand social messages from multiple developmental contexts in efforts to reduce adolescent alcohol consumption and alcohol-related risk-taking.

  3. Solar sail time-optimal interplanetary transfer trajectory design

    International Nuclear Information System (INIS)

    Gong Shengpin; Gao Yunfeng; Li Junfeng

    2011-01-01

    The fuel consumption associated with some interplanetary transfer trajectories using chemical propulsion is not affordable. A solar sail is a method of propulsion that does not consume fuel. Transfer time is one of the most pressing problems of solar sail transfer trajectory design. This paper investigates the time-optimal interplanetary transfer trajectories to a circular orbit of given inclination and radius. The optimal control law is derived from the principle of maximization. An indirect method is used to solve the optimal control problem by selecting values for the initial adjoint variables, which are normalized within a unit sphere. The conditions for the existence of the time-optimal transfer are dependent on the lightness number of the sail and the inclination and radius of the target orbit. A numerical method is used to obtain the boundary values for the time-optimal transfer trajectories. For the cases where no time-optimal transfer trajectories exist, first-order necessary conditions of the optimal control are proposed to obtain feasible solutions. The results show that the transfer time decreases as the minimum distance from the Sun decreases during the transfer duration. For a solar sail with a small lightness number, the transfer time may be evaluated analytically for a three-phase transfer trajectory. The analytical results are compared with previous results and the associated numerical results. The transfer time of the numerical result here is smaller than the transfer time from previous results and is larger than the analytical result.

  4. Which Better Predicts Conduct Problems? The Relationship of Trajectories of Conduct Problems with ODD and ADHD Symptoms from Childhood into Adolescence

    Science.gov (United States)

    van Lier, Pol A. C.; van der Ende, Jan; Koot, Hans M.; Verhulst, Frank C.

    2007-01-01

    Background: To assess the co-occurrence in deviant trajectories of parent-rated symptoms of conduct disorder (CD), oppositional defiant disorder (ODD) and attention-deficit/hyperactivity disorder (ADHD) from age 4 to 18 years old in a general population sample of Dutch children. Methods: Developmental trajectories of CD, ODD, and ADHD were…

  5. Galileo's Trajectory with Mild Resistance

    Science.gov (United States)

    Groetsch, C. W.

    2012-01-01

    An aspect of Galileo's classical trajectory that persists in a simple resistance model is noted. The resistive model provides a case study for the classroom analysis of limiting behaviour of an implicitly defined function. (Contains 1 note.)

  6. Flight test trajectory control analysis

    Science.gov (United States)

    Walker, R.; Gupta, N.

    1983-01-01

    Recent extensions to optimal control theory applied to meaningful linear models with sufficiently flexible software tools provide powerful techniques for designing flight test trajectory controllers (FTTCs). This report describes the principal steps for systematic development of flight trajectory controllers, which can be summarized as planning, modeling, designing, and validating a trajectory controller. The techniques have been kept as general as possible and should apply to a wide range of problems where quantities must be computed and displayed to a pilot to improve pilot effectiveness and to reduce workload and fatigue. To illustrate the approach, a detailed trajectory guidance law is developed and demonstrated for the F-15 aircraft flying the zoom-and-pushover maneuver.

  7. Long Range Aircraft Trajectory Prediction

    OpenAIRE

    Magister, Tone

    2009-01-01

    The subject of the paper is the improvement of the aircraft future trajectory prediction accuracy for long-range airborne separation assurance. The strategic planning of safe aircraft flights and effective conflict avoidance tactics demand timely and accurate conflict detection based upon future four–dimensional airborne traffic situation prediction which is as accurate as each aircraft flight trajectory prediction. The improved kinematics model of aircraft relative flight considering flight ...

  8. The Domain of Developmental Psychopathology.

    Science.gov (United States)

    Sroufe, L. Alan; Rutter, Michael

    1984-01-01

    Describes how developmental psychopathology differs from related disciplines, including abnormal psychology, psychiatry, clinical child psychology, and developmental psychology. Points out propositions underlying a developmental perspective and discusses implications for research in developmental psychopathology. (Author/RH)

  9. Posttraumatic stress symptom trajectories among children exposed to violence.

    Science.gov (United States)

    Miller-Graff, Laura E; Howell, Kathryn H

    2015-02-01

    Little research has examined the developmental course of posttraumatic stress symptoms (PTSS) in children. The current study aimed to identify developmental trajectories of PTSS in childhood and to examine predictors of symptom presentation in 1,178 children from the Longitudinal Studies of Child Abuse and Neglect (LONGSCAN) studies, a consortium of studies focusing on the causes and effects of child maltreatment. Most children had a history of documented reports with Child Protective Services (CPS) and all were identified as living in high-risk environments. Using group-based trajectory modeling, 3 unique developmental trajectories were identified: Resilient, Clinical-Improving (PTSS in the clinical range at baseline then declining over time), and Borderline-Stable (chronically subclinical PTSS). Children in the Clinical-Improving group were more likely than children in the Resilient group to have reports of physical abuse (RRR = 1.76), emotional abuse (RRR = 2.55), neglect (RRR = 1.57), and exposure to violence at home and in the community (RRR = 1.04). Children in the Borderline-Stable group were more likely than children in the Resilient group to have a CPS history of neglect (RRR = 2.44) and exposure to violence at home and in the community (RRR = 1.04). Many children living in high-risk environments exhibit resilience to PTSS, but exposure to witnessed violence and neglect appear to put children at chronic risk for poor adjustment. These children may require more intensive, integrated clinical services that attend to multiple adverse experiences. Copyright © 2015 International Society for Traumatic Stress Studies.

  10. Factors that Influence Trajectories of Delinquency Throughout Adolescence.

    Science.gov (United States)

    Evans, Sara Z; Simons, Leslie Gordon; Simons, Ronald L

    2016-01-01

    Given that one of the most powerful predictors of adult crime is the presence of behavior problems in childhood and adolescence, there is a need to further understand factors that determine behavior patterns during this developmental stage. This study focuses on stressful life experiences such as exposure to delinquent peers, racial discrimination, as well as family characteristics such as parenting style and family transitions. Data come from four waves of the Family and Community Health Survey, an African-American sample. The present study investigates 354 males from this dataset. We utilize a group-based trajectory model to estimate the number and type of trajectories of delinquency. We then estimate multinomial regression models to predict trajectory group membership. The results indicated that there were four distinct groups of offenders (negligible delinquents; early starter/declining; late starter; and early starter/chronic offenders). We predicted group membership using both early predictors and measures of change in these predictors across the study period. The results indicated that individuals who experience greater racial discrimination (both early in childhood and throughout adolescence) are more likely to be in trajectory groups that begin offending early and persist through adolescence. Additionally, those respondents who reported having friends with greater delinquent behavior were more likely to be in groups that began their offending early in life and persisted when compared to groups who started later or desisted as they entered adulthood. The results contribute to developmental research and provide information that may be helpful in preventing adolescents from persisting in antisocial behavior as they enter adulthood.

  11. Developmental Programming, a Pathway to Disease

    Science.gov (United States)

    Cardoso, Rodolfo C.; Puttabyatappa, Muraly

    2016-01-01

    Accumulating evidence suggests that insults occurring during the perinatal period alter the developmental trajectory of the fetus/offspring leading to long-term detrimental outcomes that often culminate in adult pathologies. These perinatal insults include maternal/fetal disease states, nutritional deficits/excess, stress, lifestyle choices, exposure to environmental chemicals, and medical interventions. In addition to reviewing the various insults that contribute to developmental programming and the benefits of animal models in addressing underlying mechanisms, this review focuses on the commonalities in disease outcomes stemming from various insults, the convergence of mechanistic pathways via which various insults can lead to common outcomes, and identifies the knowledge gaps in the field and future directions. PMID:26859334

  12. Genome Transfer Prevents Fragmentation and Restores Developmental Potential of Developmentally Compromised Postovulatory Aged Mouse Oocytes

    Directory of Open Access Journals (Sweden)

    Mitsutoshi Yamada

    2017-03-01

    Full Text Available Changes in oocyte quality can have great impact on the developmental potential of early embryos. Here we test whether nuclear genome transfer from a developmentally incompetent to a developmentally competent oocyte can restore developmental potential. Using in vitro oocyte aging as a model system we performed nuclear transfer in mouse oocytes at metaphase II or at the first interphase, and observed that development to the blastocyst stage and to term was as efficient as in control embryos. The increased developmental potential is explained primarily by correction of abnormal cytokinesis at anaphase of meiosis and mitosis, by a reduction in chromosome segregation errors, and by normalization of the localization of chromosome passenger complex components survivin and cyclin B1. These observations demonstrate that developmental decline is primarily due to abnormal function of cytoplasmic factors involved in cytokinesis, while the genome remains developmentally fully competent.

  13. Geometrical properties of systems with spiral trajectories in R^3

    Directory of Open Access Journals (Sweden)

    Luka Korkut

    2015-10-01

    Full Text Available We study a class of second-order nonautonomous differential equations, and the corresponding planar and spatial systems, from the geometrical point of view. The oscillatory behavior of solutions at infinity is measured by oscillatory and phase dimensions, The oscillatory dimension is defined as the box dimension of the reflected solution near the origin, while the phase dimension is defined as the box dimension of a trajectory of the planar system in the phase plane. Using the phase dimension of the second-order equation we compute the box dimension of a spiral trajectory of the spatial system. This phase dimension of the second-order equation is connected to the asymptotic of the associated Poincare map. Also, the box dimension of a trajectory of the reduced normal form with one eigenvalue equals zero, and a pair of pure imaginary eigenvalues is computed when limit cycles bifurcate from the origin.

  14. Fluctuation theorems and atypical trajectories

    International Nuclear Information System (INIS)

    Sahoo, M; Lahiri, S; Jayannavar, A M

    2011-01-01

    In this work, we have studied simple models that can be solved analytically to illustrate various fluctuation theorems. These fluctuation theorems provide symmetries individually to the distributions of physical quantities such as the classical work (W c ), thermodynamic work (W), total entropy (Δs tot ) and dissipated heat (Q), when the system is driven arbitrarily out of equilibrium. All these quantities can be defined for individual trajectories. We have studied the number of trajectories which exhibit behaviour unexpected at the macroscopic level. As the time of observation increases, the fraction of such atypical trajectories decreases, as expected at the macroscale. The distributions for the thermodynamic work and entropy production in nonlinear models may exhibit a peak (most probable value) in the atypical regime without violating the expected average behaviour. However, dissipated heat and classical work exhibit a peak in the regime of typical behaviour only.

  15. Malware Normalization

    OpenAIRE

    Christodorescu, Mihai; Kinder, Johannes; Jha, Somesh; Katzenbeisser, Stefan; Veith, Helmut

    2005-01-01

    Malware is code designed for a malicious purpose, such as obtaining root privilege on a host. A malware detector identifies malware and thus prevents it from adversely affecting a host. In order to evade detection by malware detectors, malware writers use various obfuscation techniques to transform their malware. There is strong evidence that commercial malware detectors are susceptible to these evasion tactics. In this paper, we describe the design and implementation of a malware normalizer ...

  16. Mining of hospital laboratory information systems: a model study defining age- and gender-specific reference intervals and trajectories for plasma creatinine in a pediatric population.

    Science.gov (United States)

    Søeby, Karen; Jensen, Peter Bjødstrup; Werge, Thomas; Sørensen, Steen

    2015-09-01

    The knowledge of physiological fluctuation and variation of even commonly used biochemical quantities in extreme age groups and during development is sparse. This challenges the clinical interpretation and utility of laboratory tests in these age groups. To explore the utility of hospital laboratory data as a source of information, we analyzed enzymatic plasma creatinine as a model analyte in two large pediatric hospital samples. Plasma creatinine measurements from 9700 children aged 0-18 years were obtained from hospital laboratory databases and partitioned into high-resolution gender- and age-groups. Normal probability plots were used to deduce parameters of the normal distributions from healthy creatinine values in the mixed hospital datasets. Furthermore, temporal trajectories were generated from repeated measurements to examine developmental patterns in periods of changing creatinine levels. Creatinine shows great age dependence from birth throughout childhood. We computed and replicated 95% reference intervals in narrow gender and age bins and showed them to be comparable to those determined in healthy population studies. We identified pronounced transitions in creatinine levels at different time points after birth and around the early teens, which challenges the establishment and usefulness of reference intervals in those age groups. The study documents that hospital laboratory data may inform on the developmental aspects of creatinine, on periods with pronounced heterogeneity and valid reference intervals. Furthermore, part of the heterogeneity in creatinine distribution is likely due to differences in biological and chronological age of children and should be considered when using age-specific reference intervals.

  17. CFD Analysis of Swing of Cricket Ball and Trajectory Prediction

    Science.gov (United States)

    G, Jithin; Tom, Josin; Ruishikesh, Kamat; Jose, Jyothish; Kumar, Sanjay

    2013-11-01

    This work aims to understand the aerodynamics associated with the flight and swing of a cricket ball and predict its flight trajectory over the course of the game: at start (smooth ball) and as the game progresses (rough ball). Asymmetric airflow over the ball due to seam orientation and surface roughness can cause flight deviation (swing). The values of Drag, Lift and Side forces which are crucial for determining the trajectory of the ball were found with the help of FLUENT using the standard K- ɛ model. Analysis was done to study how the ball velocity, spin imparted to be ball and the tilt of the seam affects the movement of the ball through air. The governing force balance equations in 3 dimensions in combination a MATLAB code which used Heun's method was used for obtaining the trajectory of the ball. The conditions for the conventional swing and reverse swing to occur were deduced from the analysis and found to be in alignment with the real life situation. Critical seam angle for maximum swing and transition speed for normal to reverse swing were found out. The obtained trajectories were compared to real life hawk eye trajectories for validation. The analysis results were in good agreement with the real life situation.

  18. Grasping trajectories in a virtual environment adhere to Weber's law.

    Science.gov (United States)

    Ozana, Aviad; Berman, Sigal; Ganel, Tzvi

    2018-06-01

    Virtual-reality and telerobotic devices simulate local motor control of virtual objects within computerized environments. Here, we explored grasping kinematics within a virtual environment and tested whether, as in normal 3D grasping, trajectories in the virtual environment are performed analytically, violating Weber's law with respect to object's size. Participants were asked to grasp a series of 2D objects using a haptic system, which projected their movements to a virtual space presented on a computer screen. The apparatus also provided object-specific haptic information upon "touching" the edges of the virtual targets. The results showed that grasping movements performed within the virtual environment did not produce the typical analytical trajectory pattern obtained during 3D grasping. Unlike as in 3D grasping, grasping trajectories in the virtual environment adhered to Weber's law, which indicates relative resolution in size processing. In addition, the trajectory patterns differed from typical trajectories obtained during 3D grasping, with longer times to complete the movement, and with maximum grip apertures appearing relatively early in the movement. The results suggest that grasping movements within a virtual environment could differ from those performed in real space, and are subjected to irrelevant effects of perceptual information. Such atypical pattern of visuomotor control may be mediated by the lack of complete transparency between the interface and the virtual environment in terms of the provided visual and haptic feedback. Possible implications of the findings to movement control within robotic and virtual environments are further discussed.

  19. Reproductive and developmental toxicology

    National Research Council Canada - National Science Library

    Gupta, Ramesh C

    2011-01-01

    .... Reproductive and Developmental Toxicology is a comprehensive and authoritative resource providing the latest literature enriched with relevant references describing every aspect of this area of science...

  20. Importance of investing in adolescence from a developmental science perspective.

    Science.gov (United States)

    Dahl, Ronald E; Allen, Nicholas B; Wilbrecht, Linda; Suleiman, Ahna Ballonoff

    2018-02-21

    This review summarizes the case for investing in adolescence as a period of rapid growth, learning, adaptation, and formational neurobiological development. Adolescence is a dynamic maturational period during which young lives can pivot rapidly-in both negative and positive directions. Scientific progress in understanding adolescent development provides actionable insights into windows of opportunity during which policies can have a positive impact on developmental trajectories relating to health, education, and social and economic success. Given current global changes and challenges that affect adolescents, there is a compelling need to leverage these advances in developmental science to inform strategic investments in adolescent health.

  1. Classical models for Regge trajectories

    International Nuclear Information System (INIS)

    Biedenharn, L.C.; Van Dam, H.; Marmo, G.; Morandi, G.; Mukunda, N.; Samuel, J.; Sudarshan, E.C.G.

    1987-01-01

    Two classical models for particles with internal structure and which describe Regge trajectories are developed. The remarkable geometric and other properties of the two internal spaces are highlighted. It is shown that the conditions of positive time-like four-velocity and energy momentum for the classical system imply strong and physically reasonable conditions on the Regge mass-spin relationship

  2. Classical Trajectories and Quantum Spectra

    Science.gov (United States)

    Mielnik, Bogdan; Reyes, Marco A.

    1996-01-01

    A classical model of the Schrodinger's wave packet is considered. The problem of finding the energy levels corresponds to a classical manipulation game. It leads to an approximate but non-perturbative method of finding the eigenvalues, exploring the bifurcations of classical trajectories. The role of squeezing turns out decisive in the generation of the discrete spectra.

  3. Visiting Vehicle Ground Trajectory Tool

    Science.gov (United States)

    Hamm, Dustin

    2013-01-01

    The International Space Station (ISS) Visiting Vehicle Group needed a targeting tool for vehicles that rendezvous with the ISS. The Visiting Vehicle Ground Trajectory targeting tool provides the ability to perform both realtime and planning operations for the Visiting Vehicle Group. This tool provides a highly reconfigurable base, which allows the Visiting Vehicle Group to perform their work. The application is composed of a telemetry processing function, a relative motion function, a targeting function, a vector view, and 2D/3D world map type graphics. The software tool provides the ability to plan a rendezvous trajectory for vehicles that visit the ISS. It models these relative trajectories using planned and realtime data from the vehicle. The tool monitors ongoing rendezvous trajectory relative motion, and ensures visiting vehicles stay within agreed corridors. The software provides the ability to update or re-plan a rendezvous to support contingency operations. Adding new parameters and incorporating them into the system was previously not available on-the-fly. If an unanticipated capability wasn't discovered until the vehicle was flying, there was no way to update things.

  4. Normal accidents

    International Nuclear Information System (INIS)

    Perrow, C.

    1989-01-01

    The author has chosen numerous concrete examples to illustrate the hazardousness inherent in high-risk technologies. Starting with the TMI reactor accident in 1979, he shows that it is not only the nuclear energy sector that bears the risk of 'normal accidents', but also quite a number of other technologies and industrial sectors, or research fields. The author refers to the petrochemical industry, shipping, air traffic, large dams, mining activities, and genetic engineering, showing that due to the complexity of the systems and their manifold, rapidly interacting processes, accidents happen that cannot be thoroughly calculated, and hence are unavoidable. (orig./HP) [de

  5. Understanding adolescent personality pathology from growth trajectories of childhood oddity.

    Science.gov (United States)

    De Clercq, Barbara; Verbeke, Lize; De Caluwé, Elien; Vercruysse, Tom; Hofmans, Joeri

    2017-10-01

    Research on developmental trajectories of early maladaptive features for understanding later personality disorders (PDs) is increasingly recognized as an important study area. The course of early odd features is highly relevant in this regard, as only a few researchers have addressed childhood oddity in the context of emerging PDs. Using latent growth modeling, the current study explores growth parameters of odd features in a mixed sample of Flemish community and referred children (N = 485) across three measurement waves with 1-year time intervals. Personality pathology was assessed at a fourth assessment point in adolescence. Beyond a general declining trend in oddity characteristics, the results demonstrated that both an early onset and an increasing trend of oddity-related characteristics over time are independent predictors of adolescent PDs. Childhood oddity tends to be the most manifest precursor for PDs with a core oddity feature (i.e., the schizotypal and borderline PD), but also appears to predict most of the other DSM-5 PDs. Results are discussed from an overarching developmental framework on PDs (Cicchetti, 2014), specifically focusing on the principle of multifinality. From a clinical perspective, the significance of increasing or steady-high childhood oddity trajectories for adolescent PDs highlights the relevance of systematic screening processes across time.

  6. Trajectories of aggressive and depressive symptoms in male and female overweight children: Do they share a common path or do they follow different routes?

    Directory of Open Access Journals (Sweden)

    Luca Cerniglia

    Full Text Available The prevalence of childhood overweight is a major social and public health issue, and primary assessment should focus on early and middle childhood, because weight gain in these phases constitutes a strong predictor of subsequent negative outcomes. Studies on community samples have shown that growth curves may follow linear or non-linear trajectories from early to middle childhood, and can differ based on sex. Overweight children may exhibit a combination of physiological and psychosocial issues, and several studies have demonstrated an association between overweight and internalizing/externalizing behavior. Nevertheless, there is a dearth of longitudinal studies on depressive and aggressive symptoms in children with high BMI. This study adopted a growth curve modeling over three phases to: (1 describe BMI trajectories in two groups of children aged 2-8 (overweight and normal weight from a community sample; (2 describe the developmental trajectories of children's aggressive and depressive symptoms from 2 to 8 years of age. Results indicate higher BMI in 2-year-old girls, with males catching up with them by age 8. While overweight females' BMIs were consistently high, males' increased at 5 and 8 years. The mean scores for aggressive symptoms at T1 (2 years of age were the same in all subjects, but a significant deviation occurred from T1 to T2 in both samples, in divergent directions. With regards to children's depressive symptoms, the two groups had different starting points, with normal weight children scoring lower than overweight youths. Overweight females showed lower depressive scores than overweight males at T1, but they surpassed boys before T2, and showed more maladaptive symptoms at T3. This study solicits professionals working in pediatric settings to consider overweight children's psychopathological risk, and to be aware that even when children's BMI does not increase from 2 to 8 years, their psychopathological symptoms may grow in

  7. Trajectories of Mexican American and mainstream cultural values among Mexican American adolescents.

    Science.gov (United States)

    Knight, George P; Basilio, Camille D; Cham, Heining; Gonzales, Nancy A; Liu, Yu; Umaña-Taylor, Adriana J

    2014-12-01

    Mexican Americans are one of the largest and fastest growing ethnic groups in the United States, yet we have limited knowledge regarding changes (i.e., developmental trajectories) in cultural orientation based upon their exposure to the Mexican American and mainstream cultures. We examined the parallel trajectories of Mexican American and mainstream cultural values in a sample of 749 Mexican American adolescents (49 % female) across assessments during the fifth grade (approximately 11 years of age), the seventh grade (approximately 13 years of age) and the tenth grade (approximately 16 years of age). We expected that these values would change over this developmental period and this longitudinal approach is more appropriate than the often used median split classification to identify distinct types of acculturation. We found four distinct acculturation trajectory groups: two trajectory groups that were increasing slightly with age in the endorsement of mainstream cultural values, one of which was relatively stable in Mexican American cultural values while the other was declining in their endorsement of these values; and two trajectory groups that were declining substantially with age in their endorsement of mainstream cultural values, one of which was also declining in Mexican American cultural values and the other which was stable in these values. These four trajectory groups differed in expected ways on a number of theoretically related cultural variables, but were not highly consistent with the median split classifications. The findings highlight the need to utilize longitudinal data to examine the developmental changes of Mexican American individual's adaptation to the ethnic and mainstream culture in order to understand more fully the processes of acculturation and enculturation.

  8. Exploring the motor development of young children with possible severe to profound cognitive and motor developmental delay by means of a questionnaire

    NARCIS (Netherlands)

    Schalen, Gertruud Henrike; van der Putten, Annette; Maes, Bea; Vlaskamp, Carla

    Aim: Early motor stimulation may be valuable for children with profound intellectual and multiple disabilities (PIMD), however limited knowledge of their typical motor developmental trajectory may be currently restraining the efficacy and specificity of this intervention. Research on young children

  9. Reconstructing Normality

    DEFF Research Database (Denmark)

    Gildberg, Frederik Alkier; Bradley, Stephen K.; Fristed, Peter Billeskov

    2012-01-01

    Forensic psychiatry is an area of priority for the Danish Government. As the field expands, this calls for increased knowledge about mental health nursing practice, as this is part of the forensic psychiatry treatment offered. However, only sparse research exists in this area. The aim of this study...... was to investigate the characteristics of forensic mental health nursing staff interaction with forensic mental health inpatients and to explore how staff give meaning to these interactions. The project included 32 forensic mental health staff members, with over 307 hours of participant observations, 48 informal....... The intention is to establish a trusting relationship to form behaviour and perceptual-corrective care, which is characterized by staff's endeavours to change, halt, or support the patient's behaviour or perception in relation to staff's perception of normality. The intention is to support and teach the patient...

  10. Pursuing Normality

    DEFF Research Database (Denmark)

    Madsen, Louise Sofia; Handberg, Charlotte

    2018-01-01

    implying an influence on whether to participate in cancer survivorship care programs. Because of "pursuing normality," 8 of 9 participants opted out of cancer survivorship care programming due to prospects of "being cured" and perceptions of cancer survivorship care as "a continuation of the disease......BACKGROUND: The present study explored the reflections on cancer survivorship care of lymphoma survivors in active treatment. Lymphoma survivors have survivorship care needs, yet their participation in cancer survivorship care programs is still reported as low. OBJECTIVE: The aim of this study...... was to understand the reflections on cancer survivorship care of lymphoma survivors to aid the future planning of cancer survivorship care and overcome barriers to participation. METHODS: Data were generated in a hematological ward during 4 months of ethnographic fieldwork, including participant observation and 46...

  11. Trajectories of delinquency and parenting styles

    NARCIS (Netherlands)

    Hoeve, M.; van Blokland, A.; Dubas, J.S.; Loeber, R; Gerris, J.R.M.; van der Laan, P.H.

    2008-01-01

    We investigated trajectories of adolescent delinquent development using data from the Pittsburgh Youth Study and examined the extent to which these different trajectories are differentially predicted by childhood parenting styles. Based on self-reported and official delinquency seriousness, covering

  12. Trajectories of Delinquency and Parenting Styles

    NARCIS (Netherlands)

    Hoeve, M.; Blokland, A.A.J.; Dubas, J.S.; Loeber, R.; Gerris, J.R.M.; Laan, P.H. van der

    2008-01-01

    We investigated trajectories of adolescent delinquent development using data from the Pittsburgh Youth Study and examined the extent to which these different trajectories are differentially predicted by childhood parenting styles. Based on self-reported and official delinquency seriousness, covering

  13. User Oriented Trajectory Search for Trip Recommendation

    KAUST Repository

    Ding, Ruogu

    2012-01-01

    Trajectory sharing and searching have received significant attention in recent years. In this thesis, we propose and investigate the methods to find and recommend the best trajectory to the traveler, and mainly focus on a novel technique named User

  14. Efficient Trajectory Options Allocation for the Collaborative Trajectory Options Program

    Science.gov (United States)

    Rodionova, Olga; Arneson, Heather; Sridhar, Banavar; Evans, Antony

    2017-01-01

    The Collaborative Trajectory Options Program (CTOP) is a Traffic Management Initiative (TMI) intended to control the air traffic flow rates at multiple specified Flow Constrained Areas (FCAs), where demand exceeds capacity. CTOP allows flight operators to submit the desired Trajectory Options Set (TOS) for each affected flight with associated Relative Trajectory Cost (RTC) for each option. CTOP then creates a feasible schedule that complies with capacity constraints by assigning affected flights with routes and departure delays in such a way as to minimize the total cost while maintaining equity across flight operators. The current version of CTOP implements a Ration-by-Schedule (RBS) scheme, which assigns the best available options to flights based on a First-Scheduled-First-Served heuristic. In the present study, an alternative flight scheduling approach is developed based on linear optimization. Results suggest that such an approach can significantly reduce flight delays, in the deterministic case, while maintaining equity as defined using a Max-Min fairness scheme.

  15. Aircraft 4D trajectories planning under uncertainties

    OpenAIRE

    Chaimatanan , Supatcha; Delahaye , Daniel; Mongeau , Marcel

    2015-01-01

    International audience; To sustain the rapidly increasing air traffic demand, the future air traffic management system will rely on a concept, called Trajectory-Based Operations (TBO), that will require aircraft to follow an assigned 4D trajectory (time-constrained trajectory) with high precision. TBO involves separating aircraft via strategic (long-term) trajectory deconfliction rather than the currently-practicing tactical (short-term) conflict resolution. In this context, this paper presen...

  16. Associations between Race and Eating Disorder Symptom Trajectories in Black and White Girls.

    Science.gov (United States)

    Bodell, Lindsay P; Wildes, Jennifer E; Cheng, Yu; Goldschmidt, Andrea B; Keenan, Kate; Hipwell, Alison E; Stepp, Stephanie D

    2018-04-01

    Epidemiological research suggests racial differences in the presentation of eating disorder symptoms. However, no studies have examined associations between race and eating disorder symptom trajectories across youth and adolescence, which is necessary to inform culturally sensitive prevention programs. The purpose of the current study was to examine the trajectories of eating disorder symptoms from childhood to young adulthood and to examine whether race was associated with trajectory group membership. Data were drawn from 2,305 Black and White girls who participated in a community-based longitudinal cohort study (Pittsburgh Girls Study) examining the development of psychopathology. The child and adult versions of the Eating Attitudes Test assessed self-reported eating disorder symptoms at six time points between ages 9 and 21 years. Growth mixture modeling was used to examine developmental trajectories of dieting, bulimia/food preoccupation, and total eating disorder symptom scores. Given potential confounds with race and disordered eating, financial strain (i.e., receiving public assistance) and weight were included as covariates. Four to six distinct developmental patterns were found across eating disorder symptoms, including none, increasing, decreasing, or increasing-decreasing trajectories. Black girls had a greater likelihood of being in the decreasing trajectories for dieting, bulimia/food preoccupation, and total eating disorder symptom scores. White girls were more likely to follow increasing trajectories of dieting and total eating disorder symptom scores compared to Black girls. These results highlight the importance of examining the influence of racial background on eating disorder symptoms and the potential need for differences in the timing and focus of prevention interventions in these groups.

  17. Towards Efficient Search for Activity Trajectories

    DEFF Research Database (Denmark)

    Zheng, Kai; Shang, Shuo; Yuan, Jing

    2013-01-01

    , recent proliferation in location-based web applications (e.g., Foursquare, Facebook) has given rise to large amounts of trajectories associated with activity information, called activity trajectory. In this paper, we study the problem of efficient similarity search on activity trajectory database. Given...

  18. Methods for control over learning individual trajectory

    Science.gov (United States)

    Mitsel, A. A.; Cherniaeva, N. V.

    2015-09-01

    The article discusses models, methods and algorithms of determining student's optimal individual educational trajectory. A new method of controlling the learning trajectory has been developed as a dynamic model of learning trajectory control, which uses score assessment to construct a sequence of studied subjects.

  19. The developmental sequence of social-communicative skills in young children with autism: a longitudinal study.

    Science.gov (United States)

    Wu, Chin-Chin; Chiang, Chung-Hsin

    2014-05-01

    To explore the different developmental trajectories of social-communicative skills in children with autism and typically developing infants, two longitudinal studies were conducted. In Study 1, we examined the developmental sequence of social-communicative skills in 26 typically developing infants when they were 9 months old and reexamined them when they were 12 and 15 months old. The results indicated a reliable developmental sequence of social-communicative skills in infants with typical development. In Study 2, we explored the emergence sequence of social-communicative skills of 23 children with autism and 23 children with developmental delay between the ages of 2 and 4 years. The results demonstrated that the developmental sequence of social-communicative skills in young children with autism and children with developmental delays was different.

  20. Life Span Developmental Approach

    Directory of Open Access Journals (Sweden)

    Ali Eryilmaz

    2011-03-01

    Full Text Available The Life Span Developmental Approach examines development of individuals which occurs from birth to death. Life span developmental approach is a multi-disciplinary approach related with disciplines like psychology, psychiatry, sociology, anthropology and geriatrics that indicates the fact that development is not completed in adulthood, it continues during the life course. Development is a complex process that consists of dying and death. This approach carefully investigates the development of individuals with respect to developmental stages. This developmental approach suggests that scientific disciplines should not explain developmental facts only with age changes. Along with aging, cognitive, biological, and socioemotional development throughout life should also be considered to provide a reasonable and acceptable context, guideposts, and reasonable expectations for the person. There are three important subjects whom life span developmental approach deals with. These are nature vs nurture, continuity vs discontinuity, and change vs stability. Researchers using life span developmental approach gather and produce knowledge on these three most important domains of individual development with their unique scientific methodology.

  1. Trajectories of low back pain

    DEFF Research Database (Denmark)

    Axén, Iben; Leboeuf-Yde, Charlotte

    2013-01-01

    Low back pain is not a self-limiting problem, but rather a recurrent and sometimes persistent disorder. To understand the course over time, detailed investigation, preferably using repeated measurements over extended periods of time, is needed. New knowledge concerning short-term trajectories...... indicates that the low back pain 'episode' is short lived, at least in the primary care setting, with most patients improving. Nevertheless, in the long term, low back pain often runs a persistent course with around two-thirds of patients estimated to be in pain after 12 months. Some individuals never have...... low back pain, but most have it on and off or persistently. Thus, the low back pain 'condition' is usually a lifelong experience. However, subgroups of patients with different back pain trajectories have been identified and linked to clinical parameters. Further investigation is warranted...

  2. Connection-based and object-based grouping in multiple-object tracking: A developmental study

    OpenAIRE

    Hallen, Ruth; Reusens, J. (Julie); Evers, K. (Kris); de-Wit, Lee; Wagemans, Johan

    2018-01-01

    textabstractDevelopmental research on Gestalt laws has previously revealed that, even as young as infancy, we are bound to group visual elements into unitary structures in accordance with a variety of organizational principles. Here, we focus on the developmental trajectory of both connection-based and object-based grouping, and investigate their impact on object formation in participants, aged 9-21 years old (N = 113), using a multiple-object tracking paradigm. Results reveal a main effect o...

  3. Developmental pathways of fitness, and not baseline, predict fitness status at the end of childhood

    OpenAIRE

    Rodrigues, Luis Paulo; Stodden, David F.; Lopes, Vítor P.

    2013-01-01

    It is generally described that children fitness levels increase along childhood. Complementary to this idea is the notion that the tracking of children’s fitness is good to moderate during this developmental time, and that baseline (initial values) of fitness are determinant on fitness development. The importance of developmental pathways has been recently reinforced by a theoretical argument that predicts that healthy lifestyle trajectories will evolve through either a positive or n...

  4. Letter and Colour Matching Tasks: Parametric Measures of Developmental Working Memory Capacity

    OpenAIRE

    Powell, Tamara L.; Arsalidou, Marie; Vogan, Vanessa M.; Taylor, Margot J.

    2014-01-01

    We investigated the mediating role of interference in developmental assessments of working memory (WM) capacity across childhood, adolescence, and young adulthood. One hundred and forty-two participants completed two versions of visuospatial (colour matching task, CMT) and verbal (letter matching task, LMT) WM tasks, which systematically varied cognitive load in a high and low interference condition. Results showed similar developmental trajectories across high interference contexts (CMT- and...

  5. Ion trajectories quadrupole mass filters

    International Nuclear Information System (INIS)

    Ursu, D.; Lupsa, N.; Muntean, F.

    1994-01-01

    The present paper aims at bringing some contributions to the understanding of ion motion in quadrupole mass filters. The theoretical treatment of quadrupole mass filter is intended to be a concise derivation of the important physical relationships using Mathieu functions. A simple iterative method of numerical computation has been used to simulate ion trajectories in an ideal quadrupole field. Finally, some examples of calculation are presented with the aid of computer graphics. (Author) 14 Figs., 1 Tab., 20 Refs

  6. Interference, reduced action, and trajectories

    OpenAIRE

    Floyd, Edward R.

    2006-01-01

    Instead of investigating the interference between two stationary, rectilinear wave functions in a trajectory representation by examining the two rectilinear wave functions individually, we examine a dichromatic wave function that is synthesized from the two interfering wave functions. The physics of interference is contained in the reduced action for the dichromatic wave function. As this reduced action is a generator of the motion for the dichromatic wave function, it determines the dichroma...

  7. Identification of digitized particle trajectories

    CERN Document Server

    Grote, H; Lassalle, J C; Zanella, P

    1973-01-01

    High-energy Physics Laboratories make increasing use of particle detectors which directly produce digital measurements of trajectories at very high rates. Data collected in vast amounts during experiments are then analysed by computer programs whose first task is the recognition of tracks and reconstruction of the interesting events. This paper discusses the applicability of various Pattern Recognition approaches. Examples are given of the problems and the practical achievements in this field.

  8. Automated trajectory planning for multiple-flyby interplanetary missions

    Science.gov (United States)

    Englander, Jacob

    Many space mission planning problems may be formulated as hybrid optimal control problems (HOCP), i.e. problems that include both real-valued variables and categorical variables. In interplanetary trajectory design problems the categorical variables will typically specify the sequence of planets at which to perform flybys, and the real-valued variables will represent the launch date, ight times between planets, magnitudes and directions of thrust, flyby altitudes, etc. The contribution of this work is a framework for the autonomous optimization of multiple-flyby interplanetary trajectories. The trajectory design problem is converted into a HOCP with two nested loops: an "outer-loop" that finds the sequence of flybys and an "inner-loop" that optimizes the trajectory for each candidate yby sequence. The problem of choosing a sequence of flybys is posed as an integer programming problem and solved using a genetic algorithm (GA). This is an especially difficult problem to solve because GAs normally operate on a fixed-length set of decision variables. Since in interplanetary trajectory design the number of flyby maneuvers is not known a priori, it was necessary to devise a method of parameterizing the problem such that the GA can evolve a variable-length sequence of flybys. A novel "null gene" transcription was developed to meet this need. Then, for each candidate sequence of flybys, a trajectory must be found that visits each of the flyby targets and arrives at the final destination while optimizing some cost metric, such as minimizing ▵v or maximizing the final mass of the spacecraft. Three different classes of trajectory are described in this work, each of which requireda different physical model and optimization method. The choice of a trajectory model and optimization method is especially challenging because of the nature of the hybrid optimal control problem. Because the trajectory optimization problem is generated in real time by the outer-loop, the inner

  9. Parental nonstandard work schedules during infancy and children's BMI trajectories

    Directory of Open Access Journals (Sweden)

    Afshin Zilanawala

    2017-09-01

    Full Text Available Background: Empirical evidence has demonstrated adverse associations between parental nonstandard work schedules (i.e., evenings, nights, or weekends and child developmental outcomes. However, there are mixed findings concerning the relationship between parental nonstandard employment and children's body mass index (BMI, and few studies have incorporated information on paternal work schedules. Objective: This paper investigated BMI trajectories from early to middle childhood (ages 3-11 by parental work schedules at 9 months of age, using nationally representative cohort data from the United Kingdom. This study is the first to examine the link between nonstandard work schedules and children's BMI in the United Kingdom. Methods: We used data from the Millennium Cohort Study (2001‒2013, n = 13,021 to estimate trajectories in BMI, using data from ages 3, 5, 7, and 11 years. Joint parental work schedules and a range of biological, socioeconomic, and psychosocial covariates were assessed in the initial interviews at 9 months. Results: Compared to children in two-parent families where parents worked standard shifts, we found steeper BMI growth trajectories for children in two-parent families where both parents worked nonstandard shifts and children in single-parent families whose mothers worked a standard shift. Fathers' shift work, compared to standard shifts, was independently associated with significant increases in BMI. Conclusions: Future public health initiatives focused on reducing the risk of rapid BMI gain in childhood can potentially consider the disruptions to family processes resulting from working nonstandard hours. Contribution: Children in families in which both parents work nonstandard schedules had steeper BMI growth trajectories across the first decade of life. Fathers' nonstandard shifts were independently associated with increases in BMI.

  10. Trajectories of Life Satisfaction across the Transition to Post-Compulsory Education: Do Adolescents Follow Different Pathways?

    Science.gov (United States)

    Salmela-Aro, Katariina; Tynkkynen, Lotta

    2010-01-01

    To examine the developmental trajectories of life satisfaction shown by adolescents during a major educational transition, 687 (327 girls, 360 boys) Finnish adolescents responded to measures of life satisfaction during the beginning of their last year in comprehensive school and three times annually thereafter during the transition to…

  11. Developmental toxicology: adequacy of current methods.

    Science.gov (United States)

    Peters, P W

    1998-01-01

    Toxicology embraces several disciplines such as carcinogenicity, mutagenicity and reproductive toxicity. Reproductive toxicology is concerned with possible effects of substances on the reproductive process, i.e. on sexual organs and their functions, endocrine regulation, fertilization, transport of the fertilized ovum, implantation, and embryonic, fetal and postnatal development, until the end-differentiation of the organs is achieved. Reproductive toxicology is divided into areas related to male and female fertility, and developmental toxicology. Developmental toxicology can be further broken down into prenatal and postnatal toxicology. Today, much new information is available about the origins of developmental disorders resulting from chemical exposure. While these findings seem to promise important new developments in methodology and research, there is a danger of losing sight of the precepts and principles established in the light of existing knowledge. There is also a danger that we may fail to correct shortcomings in our existing procedures and practice. The aim of this presentation is to emphasize the importance of testing substances for their impact in advance of their use and to underline that we must use the best existing tools for carrying out risk assessments. Moreover, it needs to be stressed that there are many substances that are never assessed with respect to reproductive and developmental toxicity. Similarly, our programmes for post-marketing surveillance with respect to developmental toxicology are grossly inadequate. Our ability to identify risks to normal development and reproduction would be much improved, first if a number of straightforward precepts were always followed and second, if we had a clearer understanding of what we mean by risk and acceptable levels of risk in the context of development. Other aims of this paper are: to stress the complexity of the different stages of normal prenatal development; to note the principles that are

  12. Reproductive and developmental toxicology

    National Research Council Canada - National Science Library

    Gupta, Ramesh C

    2011-01-01

    .... With a special focus on placental toxicity, this book is the only available reference to connect the three key risk stages, and is the only resource to include reproductive and developmental toxicity in domestic animals, fish, and wildlife.

  13. Developmental coordination disorder

    Science.gov (United States)

    Developmental coordination disorder can lead to: Learning problems Low self-esteem resulting from poor ability at sports and teasing by other children Repeated injuries Weight gain as a result of not wanting to participate ...

  14. Facts about Developmental Disabilities

    Science.gov (United States)

    ... play, learn, speak, behave, and move (for example, crawling and walking). Children develop at their own pace, ... person’s lifetime. Most developmental disabilities begin before a baby is born, but some can happen after birth ...

  15. Gene expression profiling in the Cynomolgus macaque Macaca fascicularis shows variation within the normal birth range

    Directory of Open Access Journals (Sweden)

    Vickers Mark H

    2011-10-01

    Full Text Available Abstract Background Although an adverse early-life environment has been linked to an increased risk of developing the metabolic syndrome, the molecular mechanisms underlying altered disease susceptibility as well as their relevance to humans are largely unknown. Importantly, emerging evidence suggests that these effects operate within the normal range of birth weights and involve mechanisms of developmental palsticity rather than pathology. Method To explore this further, we utilised a non-human primate model Macaca fascicularis (Cynomolgus macaque which shares with humans the same progressive history of the metabolic syndrome. Using microarray we compared tissues from neonates in the average birth weight (50-75th centile to those of lower birth weight (5-25th centile and studied the effect of different growth trajectories within the normal range on gene expression levels in the umbilical cord, neonatal liver and skeletal muscle. Results We identified 1973 genes which were differentially expressed in the three tissue types between average and low birth weight animals (P Conclusion These differences in gene expression levels between animals in the upper and lower percentiles of the normal birth weight range may point towards early life metabolic adaptations that in later life result in differences in disease risk.

  16. How Evolution May Work Through Curiosity-Driven Developmental Process.

    Science.gov (United States)

    Oudeyer, Pierre-Yves; Smith, Linda B

    2016-04-01

    Infants' own activities create and actively select their learning experiences. Here we review recent models of embodied information seeking and curiosity-driven learning and show that these mechanisms have deep implications for development and evolution. We discuss how these mechanisms yield self-organized epigenesis with emergent ordered behavioral and cognitive developmental stages. We describe a robotic experiment that explored the hypothesis that progress in learning, in and for itself, generates intrinsic rewards: The robot learners probabilistically selected experiences according to their potential for reducing uncertainty. In these experiments, curiosity-driven learning led the robot learner to successively discover object affordances and vocal interaction with its peers. We explain how a learning curriculum adapted to the current constraints of the learning system automatically formed, constraining learning and shaping the developmental trajectory. The observed trajectories in the robot experiment share many properties with those in infant development, including a mixture of regularities and diversities in the developmental patterns. Finally, we argue that such emergent developmental structures can guide and constrain evolution, in particular with regard to the origins of language. Copyright © 2016 Cognitive Science Society, Inc.

  17. A Developmental Neuroscience Perspective on Affect-Biased Attention

    Science.gov (United States)

    Morales, Santiago; Fu, Xiaoxue; Pérez-Edgar, Koraly E.

    2016-01-01

    There is growing interest regarding the impact of affect-biased attention on psychopathology. However, most of the research to date lacks a developmental approach. In the present review, we examine the role affect-biased attention plays in shaping socioemotional trajectories within a developmental neuroscience framework. We propose that affect-biased attention, particularly if stable and entrenched, acts as a developmental tether that helps sustain early socioemotional and behavioral profiles over time, placing some individuals on maladaptive developmental trajectories. Although most of the evidence is found in the anxiety literature, we suggest that these relations may operate across multiple domains of interest, including positive affect, externalizing behaviors, drug use, and eating behaviors. We also review the general mechanisms and neural correlates of affect-biased attention, as well as the current evidence for the co-development of attention and affect. Based on the reviewed literature, we propose a model that may help us better understand the nuances of affect-biased attention across development. The model may serve as a strong foundation for ongoing attempts to identify neurocognitive mechanisms and intervene with individuals at risk. Finally, we discuss open issues for future research that may help bridge existing gaps in the literature. PMID:27606972

  18. A fast computing method to distinguish the hyperbolic trajectory of an non-autonomous system

    Science.gov (United States)

    Jia, Meng; Fan, Yang-Yu; Tian, Wei-Jian

    2011-03-01

    Attempting to find a fast computing method to DHT (distinguished hyperbolic trajectory), this study first proves that the errors of the stable DHT can be ignored in normal direction when they are computed as the trajectories extend. This conclusion means that the stable flow with perturbation will approach to the real trajectory as it extends over time. Based on this theory and combined with the improved DHT computing method, this paper reports a new fast computing method to DHT, which magnifies the DHT computing speed without decreasing its accuracy. Project supported by the National Natural Science Foundation of China (Grant No. 60872159).

  19. A fast computing method to distinguish the hyperbolic trajectory of an non-autonomous system

    International Nuclear Information System (INIS)

    Jia Meng; Fan Yang-Yu; Tian Wei-Jian

    2011-01-01

    Attempting to find a fast computing method to DHT (distinguished hyperbolic trajectory), this study first proves that the errors of the stable DHT can be ignored in normal direction when they are computed as the trajectories extend. This conclusion means that the stable flow with perturbation will approach to the real trajectory as it extends over time. Based on this theory and combined with the improved DHT computing method, this paper reports a new fast computing method to DHT, which magnifies the DHT computing speed without decreasing its accuracy. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)

  20. Life Span Developmental Approach

    OpenAIRE

    Ali Eryilmaz

    2011-01-01

    The Life Span Developmental Approach examines development of individuals which occurs from birth to death. Life span developmental approach is a multi-disciplinary approach related with disciplines like psychology, psychiatry, sociology, anthropology and geriatrics that indicates the fact that development is not completed in adulthood, it continues during the life course. Development is a complex process that consists of dying and death. This approach carefully investigates the development of...

  1. Emigration trajectories of former Portuguese emigrants: the construction of family integrity

    Directory of Open Access Journals (Sweden)

    Filipa Daniela Marques

    2012-06-01

    Full Text Available Constructing family integrity is a normative developmental challenge for older people, which is influenced by the family and social systems. This exploratory study examines the emigration trajectories of former Portuguese emigrants, now in old age, who returned to their home country (Portugal. And aims to contribute to a better understand of the influence of emigration experiences in the construction of family integrity versus disconnection and alienation.

  2. Trajectories of social withdrawal and cognitive decline in the schizophrenia prodrome.

    Science.gov (United States)

    Cullen, Kathryn; Guimaraes, Angela; Wozniak, Jeffrey; Anjum, Afshan; Schulz, S Charles; White, Tonya

    2011-01-01

    Schizophrenia is a heterogeneous neurodevelopmental disorder. Patients with high levels of negative symptoms have been identified as a specific subtype, but little is known about how the neurodevelopmental course may differ in this group. This study aimed to characterize developmental trajectories of premorbid social withdrawal and cognitive decline between patients with high versus low levels of negative symptoms in youth with schizophrenia-spectrum disorders. A standardized timeline was used to delineate the emergence of psychosis, social withdrawal, and cognitive decline in 52 subjects aged 8 to 19 with schizophrenia (n=36), schizophreniform (n=6), or schizoaffective disorder (n=10). The sample was divided into subgroups of high- (n=26) versus low- (n=26) negative symptoms, and developmental trajectories of premorbid symptoms were compared between groups. Mean ages for emergence of social withdrawal, cognitive decline, and psychosis were 11.1 years (SD=2.5), 11.9 (SD=4.4) and 13.2 years (SD=1.2), respectively. In the high-negative symptom group, the premorbid developmental trajectory for social withdrawal was more protracted. This group also had more severe cognitive decline at the onset of psychosis, but the premorbid trajectories for cognitive decline did not differ significantly between groups. This work documents a more severe and protracted trajectory of premorbid social withdrawal in patients with high levels of negative symptoms in comparison to those with low-negative symptoms. The findings reported here are supportive of the hypothesis that patients with illness characterized by high levels of negative symptoms may represent a subgroup with distinct neurodevelopmental abnormalities.

  3. Preliminary Assessment of Operational Hazards and Safety Requirements for Airborne Trajectory Management (ABTM) Roadmap Applications

    Science.gov (United States)

    Cotton, William B.; Hilb, Robert; Koczo, Stefan, Jr.; Wing, David J.

    2016-01-01

    A set of five developmental steps building from the NASA TASAR (Traffic Aware Strategic Aircrew Requests) concept are described, each providing incrementally more efficiency and capacity benefits to airspace system users and service providers, culminating in a Full Airborne Trajectory Management capability. For each of these steps, the incremental Operational Hazards and Safety Requirements are identified for later use in future formal safety assessments intended to lead to certification and operational approval of the equipment and the associated procedures. Two established safety assessment methodologies that are compliant with the FAA's Safety Management System were used leading to Failure Effects Classifications (FEC) for each of the steps. The most likely FEC for the first three steps, Basic TASAR, Digital TASAR, and 4D TASAR, is "No effect". For step four, Strategic Airborne Trajectory Management, the likely FEC is "Minor". For Full Airborne Trajectory Management (Step 5), the most likely FEC is "Major".

  4. Trajectories of schizotypy and their emotional and social functioning: An 18-month follow-up study.

    Science.gov (United States)

    Wang, Yi; Shi, Hai-Song; Liu, Wen-Hua; Xie, Dong-Jie; Geng, Fu-Lei; Yan, Chao; Wang, Ya; Xiao, Ya-Hui; So, Suzanne H W; Chiu, Chui-De; Leung, Patrick W L; Cheung, Eric F C; Gooding, Diane C; Chan, Raymond C K

    2018-03-01

    Schizotypy is a set of personality traits that convey liability to develop schizophrenia. Studying schizotypy in healthy individuals may facilitate the understanding of the psychopathological processes underlying schizophrenia. The present study aimed to examine the developmental trajectories of schizotypy over time using a longitudinal study design. The Chapman Scales for Psychosis Proneness were administered to 1541 college students at baseline, and subsequently at six-monthly intervals up to 18months. Latent class growth analysis was conducted to track the different trajectories. In addition, self-reported scales were used to measure idea of reference, emotional experiences and expression, stress and coping, as well as social functioning. We identified four latent classes with distinct trajectories: "nonschizotypy" group (LC1), "stable high schizotypy" group (LC3), "high reactive schizotypy" group (LC2) and "low reactive schizotypy" group (LC4). These findings suggest that there may be distinct developmental trajectories for schizotypy. Two groups may be of particular interest: the "stable high schizotypy" group that displayed the worst clinical and functioning outcomes on almost all measures and the "high reactive schizotypy" group characterized by a relatively rapid decline in functioning. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Conduct Disorder and Alcohol Use Disorder Trajectories, Predictors, and Outcomes for Indigenous Youth.

    Science.gov (United States)

    Greenfield, Brenna L; Sittner, Kelley J; Forbes, Miriam K; Walls, Melissa L; Whitbeck, Les B

    2017-02-01

    The aim of this study was to identify separate and joint trajectories of conduct disorder (CD) and alcohol use disorder (AUD) DSM-IV diagnostic symptoms among American Indian and First Nation (Indigenous) youth aged 10 to 18 years, and to characterize baseline profiles and later outcomes associated with joint trajectory group membership. Data were collected between 2002 and 2010 on three indigenous reservations in the northern Midwest and four Canadian reserves (N = 673). CD and substance use disorder (SUD) were measured using the DSM-IV Diagnostic Interview Schedule for Children-Revised (DISC-R), administered at four time points. Using group-based trajectory modeling, three CD and four AUD trajectories were found. Both had a small group with high symptoms, but the largest groups for both had no symptoms (55% and 73%, respectively). CD symptom trajectories began at age 10 years and peaked at age 14; AUD trajectories began at age 12 years and were highest from age 16 on. Eight joint trajectories were identified. Of the sample, 53% fell into the group with no CD or AUD symptoms. Compared to symptomatic groups, this group had greater caretaker warmth, positive school adjustment, less discrimination, and fewer deviant peers, and were less likely to have a caretaker with major depression at baseline. Symptomatic groups had higher odds of high school dropout, sex under the influence, and arrest at age 17 to 20 years. Despite significant risk factors, a large proportion of Indigenous youth had no CD-SUD symptoms over time. CD-SUD symptoms have multiple development trajectories and are related to early developmental risk and later psychosocial outcomes. Copyright © 2016 American Academy of Child and Adolescent Psychiatry. Published by Elsevier Inc. All rights reserved.

  6. Transgenerational developmental programming.

    Science.gov (United States)

    Aiken, Catherine E; Ozanne, Susan E

    2014-01-01

    The concept of developmental programming suggests that the early life environment influences offspring characteristics in later life, including the propensity to develop diseases such as the metabolic syndrome. There is now growing evidence that the effects of developmental programming may also manifest in further generations without further suboptimal exposure. This review considers the evidence, primarily from rodent models, for effects persisting to subsequent generations, and evaluates the mechanisms by which developmental programming may be transmitted to further generations. In particular, we focus on the potential role of the intrauterine environment in contributing to a developmentally programmed phenotype in subsequent generations. The literature was systematically searched at http://pubmed.org and http://scholar.google.com to identify published findings regarding transgenerational (F2 and beyond) developmental programming effects in human populations and animal models. Transmission of programming effects is often viewed as a form of epigenetic inheritance, either via the maternal or paternal line. Evidence exists for both germline and somatic inheritance of epigenetic modifications which may be responsible for phenotypic changes in further generations. However, there is increasing evidence for the role of both extra-genomic components of the zygote and the interaction of the developing conceptus with the intrauterine environment in propagating programming effects. The contribution of a suboptimal reproductive tract environment or maternal adaptations to pregnancy may be critical to inheritance of programming effects via the maternal line. As the effects of age exacerbate the programmed metabolic phenotype, advancing maternal age may increase the likelihood of developmental programming effects being transmitted to further generations. We suggest that developmental programming effects could be propagated through the maternal line de novo in generations

  7. Cognitive-emotional interplay:implications for children’s development of self-aware emotion regulation as the last developmental phase of emotional intelligence

    OpenAIRE

    Kralj, S. (Sara)

    2016-01-01

    Abstract Cognitive and emotional developmental trajectories account for individual differences in children. Individual variations of emotional intelligence may be a result of various factors. For the purpose of this work children’s development of emotional intelligence is examined through individual developmental aspect related to development of cognition and emotion. The ability to be aware of own emotions and emotions of ...

  8. Optimal trajectories of aircraft and spacecraft

    Science.gov (United States)

    Miele, A.

    1990-01-01

    Work done on algorithms for the numerical solutions of optimal control problems and their application to the computation of optimal flight trajectories of aircraft and spacecraft is summarized. General considerations on calculus of variations, optimal control, numerical algorithms, and applications of these algorithms to real-world problems are presented. The sequential gradient-restoration algorithm (SGRA) is examined for the numerical solution of optimal control problems of the Bolza type. Both the primal formulation and the dual formulation are discussed. Aircraft trajectories, in particular, the application of the dual sequential gradient-restoration algorithm (DSGRA) to the determination of optimal flight trajectories in the presence of windshear are described. Both take-off trajectories and abort landing trajectories are discussed. Take-off trajectories are optimized by minimizing the peak deviation of the absolute path inclination from a reference value. Abort landing trajectories are optimized by minimizing the peak drop of altitude from a reference value. Abort landing trajectories are optimized by minimizing the peak drop of altitude from a reference value. The survival capability of an aircraft in a severe windshear is discussed, and the optimal trajectories are found to be superior to both constant pitch trajectories and maximum angle of attack trajectories. Spacecraft trajectories, in particular, the application of the primal sequential gradient-restoration algorithm (PSGRA) to the determination of optimal flight trajectories for aeroassisted orbital transfer are examined. Both the coplanar case and the noncoplanar case are discussed within the frame of three problems: minimization of the total characteristic velocity; minimization of the time integral of the square of the path inclination; and minimization of the peak heating rate. The solution of the second problem is called nearly-grazing solution, and its merits are pointed out as a useful

  9. Irritability Trajectories, Cortical Thickness, and Clinical Outcomes in a Sample Enriched for Preschool Depression.

    Science.gov (United States)

    Pagliaccio, David; Pine, Daniel S; Barch, Deanna M; Luby, Joan L; Leibenluft, Ellen

    2018-05-01

    Cross-sectional, longitudinal, and genetic associations exist between irritability and depression. Prior studies have examined developmental trajectories of irritability, clinical outcomes, and associations with child and familial depression. However, studies have not integrated neurobiological measures. The present study examined developmental trajectories of irritability, clinical outcomes, and cortical structure among preschoolers oversampled for depressive symptoms. Beginning at 3 to 5 years old, a sample of 271 children enriched for early depressive symptoms were assessed longitudinally by clinical interview. Latent class mixture models identified trajectories of irritability severity. Risk factors, clinical outcomes, and cortical thickness were compared across trajectory classes. Cortical thickness measures were extracted from 3 waves of magnetic resonance imaging at 7 to 12 years of age. Three trajectory classes were identified among these youth: 53.50% of children exhibited elevated irritability during preschool that decreased longitudinally, 30.26% exhibited consistently low irritability, and 16.24% exhibited consistently elevated irritability. Compared with other classes, the elevated irritability class exhibited higher rates of maternal depression, early life adversity, later psychiatric diagnoses, and functional impairment. Further, elevated baseline irritability predicted later depression beyond adversity and personal and maternal depression history. The elevated irritability class exhibited a thicker cortex in the left superior frontal and temporal gyri and the right inferior parietal lobule. Irritability manifested with specific developmental trajectories in this sample enriched for early depression. Persistently elevated irritability predicted poor psychiatric outcomes, higher risk for later depression, and decreased overall function later in development. Greater frontal, temporal, and parietal cortical thickness also was found, providing neural

  10. The Role of Early Childhood Personality in the Developmental Course of Social Adjustment

    Science.gov (United States)

    Kavcic, Tina; Podlesek, Anja; Zupancic, Maja

    2012-01-01

    This study explored children, preschool, and family characteristics that contribute to individual differences in the developmental trajectories of social competence and internalizing and externalizing behavior. Teachers reported on personality and social adjustment of 304 children at ages 3, 4, 5, and 6 years. Predictors of social adjustment…

  11. Developmental Precursors of Number of Sexual Partners from Ages 16 to 22

    Science.gov (United States)

    Lansford, Jennifer E.; Yu, Tianyi; Erath, Stephen A.; Pettit, Gregory S.; Bates, John E.; Dodge, Kenneth A.

    2010-01-01

    This study examines family and child characteristics, parent and peer relationships, and early adolescent behavior as statistical predictors of trajectories of number of sexual partners from midadolescence through early adulthood using data from 527 participants in the Child Development Project. Early adolescent developmental antecedents accounted…

  12. The developmental course of anxiety symptoms during adolescence : the TRAILS study

    NARCIS (Netherlands)

    Van Oort, F. V. A.; Greaves-Lord, K.; Verhulst, F. C.; Ormel, J.; Huizink, A. C.

    2009-01-01

    Background: Little is known about the development of anxiety symptoms from late childhood to late adolescence. The present study determined developmental trajectories of symptoms of separation anxiety disorder (SAD), social phobia (SoPh), generalized anxiety disorder (GAD), panic disorder (PD), and

  13. Developmental-Genetic Effects on Level and Change in Childhood Fears of Twins during Adolescence

    Science.gov (United States)

    Eaves, Lindon J.; Silberg, Judy L.

    2008-01-01

    Background: If the adaptive significance of specific fears changes with age, the genetic contribution to individual differences may be lowest at the age of greatest salience. The roles of genes and environment in the developmental-genetic trajectory of five common childhood fears are explored in 1094 like-sex pairs of male and female monozygotic…

  14. The Developmental Course of Anxiety Symptoms during Adolescence: The TRAILS Study

    Science.gov (United States)

    Van Oort, F. V. A.; Greaves-Lord, K.; Verhulst, F. C.; Ormel, J.; Huizink, A. C.

    2009-01-01

    Background: Little is known about the development of anxiety symptoms from late childhood to late adolescence. The present study determined developmental trajectories of symptoms of separation anxiety disorder (SAD), social phobia (SoPh), generalized anxiety disorder (GAD), panic disorder (PD), and obsessive-compulsive disorder (OCD) in a large…

  15. Ray trajectories for Alcubierre spacetime

    International Nuclear Information System (INIS)

    Anderson, Tom H; Mackay, Tom G; Lakhtakia, Akhlesh

    2011-01-01

    The Alcubierre spacetime was simulated by means of a Tamm medium which is asymptotically identical to vacuum and has constitutive parameters which are continuous functions of the spatial coordinates. Accordingly, the Tamm medium is amenable to physical realization as a micro- or nanostructured metamaterial. A comprehensive characterization of ray trajectories in the Tamm medium was undertaken, within the geometric-optics regime. Propagation directions corresponding to evanescent waves were identified: these occur in the region of the Tamm medium which corresponds to the warp bubble of the Alcubierre spacetime, especially for directions perpendicular to the velocity of the warp bubble at high speeds of that bubble. Ray trajectories are acutely sensitive to the magnitude and direction of the warp bubble's velocity, but rather less sensitive to the thickness of the transition zone between the warp bubble and its background. In particular, for rays which travel in the same direction as the warp bubble, the latter acts as a focusing lens, most notably at high speeds

  16. WE-AB-209-06: Dynamic Collimator Trajectory Algorithm for Use in VMAT Treatment Deliveries

    Energy Technology Data Exchange (ETDEWEB)

    MacDonald, L [Department of Medical Physics, Dalhousie University, Halifax, Nova Scotia, CA (Canada); Thomas, C; Syme, A [Department of Medical Physics, Dalhousie University, Halifax, Nova Scotia, CA (Canada); Department of Radiation Oncology, Dalhousie University, Halifax, Nova Scotia (Canada); Medical Physics, Nova Scotia Cancer Centre, Halifax, Nova Scotia (Canada)

    2016-06-15

    Purpose: To develop advanced dynamic collimator positioning algorithms for optimal beam’s-eye-view (BEV) fitting of targets in VMAT procedures, including multiple metastases stereotactic radiosurgery procedures. Methods: A trajectory algorithm was developed, which can dynamically modify the angle of the collimator as a function of VMAT control point to provide optimized collimation of target volume(s). Central to this algorithm is a concept denoted “whitespace”, defined as area within the jaw-defined BEV field, outside of the PTV, and not shielded by the MLC when fit to the PTV. Calculating whitespace at all collimator angles and every control point, a two-dimensional topographical map depicting the tightness-of-fit of the MLC was generated. A variety of novel searching algorithms identified a number of candidate trajectories of continuous collimator motion. Ranking these candidate trajectories according to their accrued whitespace value produced an optimal solution for navigation of this map. Results: All trajectories were normalized to minimum possible (i.e. calculated without consideration of collimator motion constraints) accrued whitespace. On an acoustic neuroma case, a random walk algorithm generated a trajectory with 151% whitespace; random walk including a mandatory anchor point improved this to 148%; gradient search produced a trajectory with 137%; and bi-directional gradient search generated a trajectory with 130% whitespace. For comparison, a fixed collimator angle of 30° and 330° accumulated 272% and 228% of whitespace, respectively. The algorithm was tested on a clinical case with two metastases (single isocentre) and identified collimator angles that allow for simultaneous irradiation of the PTVs while minimizing normal tissue irradiation. Conclusion: Dynamic collimator trajectories have the potential to improve VMAT deliveries through increased efficiency and reduced normal tissue dose, especially in treatment of multiple cranial metastases

  17. WE-AB-209-06: Dynamic Collimator Trajectory Algorithm for Use in VMAT Treatment Deliveries

    International Nuclear Information System (INIS)

    MacDonald, L; Thomas, C; Syme, A

    2016-01-01

    Purpose: To develop advanced dynamic collimator positioning algorithms for optimal beam’s-eye-view (BEV) fitting of targets in VMAT procedures, including multiple metastases stereotactic radiosurgery procedures. Methods: A trajectory algorithm was developed, which can dynamically modify the angle of the collimator as a function of VMAT control point to provide optimized collimation of target volume(s). Central to this algorithm is a concept denoted “whitespace”, defined as area within the jaw-defined BEV field, outside of the PTV, and not shielded by the MLC when fit to the PTV. Calculating whitespace at all collimator angles and every control point, a two-dimensional topographical map depicting the tightness-of-fit of the MLC was generated. A variety of novel searching algorithms identified a number of candidate trajectories of continuous collimator motion. Ranking these candidate trajectories according to their accrued whitespace value produced an optimal solution for navigation of this map. Results: All trajectories were normalized to minimum possible (i.e. calculated without consideration of collimator motion constraints) accrued whitespace. On an acoustic neuroma case, a random walk algorithm generated a trajectory with 151% whitespace; random walk including a mandatory anchor point improved this to 148%; gradient search produced a trajectory with 137%; and bi-directional gradient search generated a trajectory with 130% whitespace. For comparison, a fixed collimator angle of 30° and 330° accumulated 272% and 228% of whitespace, respectively. The algorithm was tested on a clinical case with two metastases (single isocentre) and identified collimator angles that allow for simultaneous irradiation of the PTVs while minimizing normal tissue irradiation. Conclusion: Dynamic collimator trajectories have the potential to improve VMAT deliveries through increased efficiency and reduced normal tissue dose, especially in treatment of multiple cranial metastases

  18. Trajectory generation for manipulators using linear quadratic optimal tracking

    Directory of Open Access Journals (Sweden)

    Olav Egeland

    1989-04-01

    Full Text Available The reference trajectory is normally known in advance in manipulator control which makes it possible to apply linear quadratic optimal tracking. This gives a control system which rounds corners and generates optimal feedforward. The method may be used for references consisting of straight-line segments as an alternative to the two-step method of using splines to smooth the reference and then applying feedforward. In addition, the method can be used for more complex trajectories. The actual dynamics of the manipulator are taken into account, and this results in smooth and accurate tracking. The method has been applied in combination with the computed torque technique and excellent performance was demonstrated in a simulation study. The method has also been applied experimentally to an industrial spray-painting robot where a saw-tooth reference was tracked. The corner was rounded extremely well, and the steady-state tracking error was eliminated by the optimal feedforward.

  19. Stochastic and fractal analysis of fracture trajectories

    Science.gov (United States)

    Bessendorf, Michael H.

    1987-01-01

    Analyses of fracture trajectories are used to investigate structures that fall between 'micro' and 'macro' scales. It was shown that fracture trajectories belong to the class of nonstationary processes. It was also found that correlation distance, which may be related to a characteristic size of a fracture process, increases with crack length. An assemblage of crack trajectory processes may be considered as a diffusive process. Chudnovsky (1981-1985) introduced a 'crack diffusion coefficient' d which reflects the ability of the material to deviate the crack trajectory from the most energetically efficient path and thus links the material toughness to its structure. For the set of fracture trajectories in AISI 304 steel, d was found to be equal to 1.04 microns. The fractal dimension D for the same set of trajectories was found to be 1.133.

  20. Distinguished trajectories in time dependent vector fields

    OpenAIRE

    Madrid, J. A. Jimenez; Mancho, Ana M.

    2008-01-01

    We introduce a new definition of distinguished trajectory that generalizes the concepts of fixed point and periodic orbit to aperiodic dynamical systems. This new definition is valid for identifying distinguished trajectories with hyperbolic and nonhyperbolic types of stability. The definition is implemented numerically and the procedure consists of determining a path of limit coordinates. It has been successfully applied to known examples of distinguished trajectories. In the context of high...

  1. Trajectories of Delinquency and Parenting Styles

    OpenAIRE

    Hoeve, Machteld; Blokland, Arjan; Dubas, Judith Semon; Loeber, Rolf; Gerris, Jan R. M.; van der Laan, Peter H.

    2007-01-01

    We investigated trajectories of adolescent delinquent development using data from the Pittsburgh Youth Study and examined the extent to which these different trajectories are differentially predicted by childhood parenting styles. Based on self-reported and official delinquency seriousness, covering ages 10?19, we identified five distinct delinquency trajectories differing in both level and change in seriousness over time: a nondelinquent, minor persisting, moderate desisting, serious persist...

  2. Decentralized flight trajectory planning of multiple aircraft

    OpenAIRE

    Yokoyama, Nobuhiro; 横山 信宏

    2008-01-01

    Conventional decentralized algorithms for optimal trajectory planning tend to require prohibitive computational time as the number of aircraft increases. To overcome this drawback, this paper proposes a novel decentralized trajectory planning algorithm adopting a constraints decoupling approach for parallel optimization. The constraints decoupling approach is formulated as the path constraints of the real-time trajectory optimization problem based on nonlinear programming. Due to the parallel...

  3. Reading in developmental prosopagnosia

    DEFF Research Database (Denmark)

    Starrfelt, Randi; Klargaard, Solja K; Petersen, Anders

    2018-01-01

    exposure durations (targeting the word superiority effect), and d) text reading. RESULTS: Participants with developmental prosopagnosia performed strikingly similar to controls across the four reading tasks. Formal analysis revealed a significant dissociation between word and face recognition......, that is, impaired reading in developmental prosopagnosia. METHOD: We tested 10 adults with developmental prosopagnosia and 20 matched controls. All participants completed the Cambridge Face Memory Test, the Cambridge Face Perception test and a Face recognition questionnaire used to quantify everyday face...... recognition experience. Reading was measured in four experimental tasks, testing different levels of letter, word, and text reading: (a) single word reading with words of varying length,(b) vocal response times in single letter and short word naming, (c) recognition of single letters and short words at brief...

  4. Trajectory similarity join in spatial networks

    KAUST Repository

    Shang, Shuo

    2017-09-07

    The matching of similar pairs of objects, called similarity join, is fundamental functionality in data management. We consider the case of trajectory similarity join (TS-Join), where the objects are trajectories of vehicles moving in road networks. Thus, given two sets of trajectories and a threshold θ, the TS-Join returns all pairs of trajectories from the two sets with similarity above θ. This join targets applications such as trajectory near-duplicate detection, data cleaning, ridesharing recommendation, and traffic congestion prediction. With these applications in mind, we provide a purposeful definition of similarity. To enable efficient TS-Join processing on large sets of trajectories, we develop search space pruning techniques and take into account the parallel processing capabilities of modern processors. Specifically, we present a two-phase divide-and-conquer algorithm. For each trajectory, the algorithm first finds similar trajectories. Then it merges the results to achieve a final result. The algorithm exploits an upper bound on the spatiotemporal similarity and a heuristic scheduling strategy for search space pruning. The algorithm\\'s per-trajectory searches are independent of each other and can be performed in parallel, and the merging has constant cost. An empirical study with real data offers insight in the performance of the algorithm and demonstrates that is capable of outperforming a well-designed baseline algorithm by an order of magnitude.

  5. Letter and Colour Matching Tasks: Parametric Measures of Developmental Working Memory Capacity

    Directory of Open Access Journals (Sweden)

    Tamara L. Powell

    2014-01-01

    Full Text Available We investigated the mediating role of interference in developmental assessments of working memory (WM capacity across childhood, adolescence, and young adulthood. One hundred and forty-two participants completed two versions of visuospatial (colour matching task, CMT and verbal (letter matching task, LMT WM tasks, which systematically varied cognitive load in a high and low interference condition. Results showed similar developmental trajectories across high interference contexts (CMT- and LMT-Complex and divergent developmental growth patterns across low interference contexts (CMT- and LMT-Simple. Performance on tasks requiring greater cognitive control was in closer agreement with developmental predictions relative to simple recall guided tasks that rely solely on the storage components of WM. These findings suggest that developmental WM capacity, as measured by the CMT and LMT paradigms, can be better quantified using high interference contexts, in both content domains, and demonstrate steady increases in WM through to mid-adolescence.

  6. The Developmental Work

    DEFF Research Database (Denmark)

    Møller, Niels; Hvid, Helge

    2001-01-01

    AbstractIn the nineties, the concept of the developmental work (DW) has become a significant point of orientation for the actors on Danish labour market. The DW has moved the focus of the labour market from wages and working time towards work and production. For employees, the DW promises...... developmental possibilities, influence and responsibility, but also greater social responsibility for the firm. For firms, the DW promises increased competitiveness and better products. In this paper we present the concept of the DW as one which encourages the development of work, production and organisation...... of the firm and show that the DW is different from mainstream management concepts, as the DW...

  7. Privacy-Preserving Trajectory Collection

    DEFF Research Database (Denmark)

    Gidofalvi, Gyozo; Xuegang, Huang; Pedersen, Torben Bach

    2008-01-01

    In order to provide context--aware Location--Based Services, real location data of mobile users must be collected and analyzed by spatio--temporal data mining methods. However, the data mining methods need precise location data, while the mobile users want to protect their location privacy....... To remedy this situation, this paper first formally defines novel location privacy requirements. Then, it briefly presents a system for privacy--preserving trajectory collection that meets these requirements. The system is composed of an untrusted server and clients communicating in a P2P network. Location...... data is anonymized in the system using data cloaking and data swapping techniques. Finally, the paper empirically demonstrates that the proposed system is effective and feasible....

  8. Mobility, Education and Life Trajectories

    DEFF Research Database (Denmark)

    Olwig, Karen Fog; Valentin, Karen

    2015-01-01

    Travel for educational purposes, once the privilege of the upper class, has become a global mass phenomenon in recent years. This special issue examines, within different cultural and historical contexts, the close relationship between migration, education and social mobility. Adopting...... the perspective that education includes a broad range of formative experiences, the articles explore different educational trajectories and the local, regional and transnational relations in which they are embedded. Three key issues emerge from the analyses: firstly, the central role of temporality in terms...... of both the overall historical conditions and the specific biographical circumstances shaping educational opportunities; secondly, the complex agendas informing individuals’ migration and the adjustment of these agendas in the light of the vagaries of migrant life; and thirdly, the importance of migrants...

  9. Entanglement evolution for quantum trajectories

    International Nuclear Information System (INIS)

    Vogelsberger, S; Spehner, D

    2011-01-01

    Entanglement is a key resource in quantum information. It can be destroyed or sometimes created by interactions with a reservoir. In recent years, much attention has been devoted to the phenomena of entanglement sudden death and sudden birth, i.e., the sudden disappearance or revival of entanglement at finite times resulting from a coupling of the quantum system to its environment. We investigate the evolution of the entanglement of noninteracting qubits coupled to reservoirs under monitoring of the reservoirs by means of continuous measurements. Because of these measurements, the qubits remain at all times in a pure state, which evolves randomly. To each measurement result (or 'realization') corresponds a quantum trajectory in the Hilbert space of the qubits. We show that for two qubits coupled to independent baths subjected to local measurements, the average of the qubits' concurrence over all quantum trajectories is either constant or decays exponentially. The corresponding decay rate depends on the measurement scheme only. This result contrasts with the entanglement sudden death phenomenon exhibited by the qubits' density matrix in the absence of measurements. Our analysis applies to arbitrary quantum jump dynamics (photon counting) as well as to quantum state diffusion (homodyne or heterodyne detections) in the Markov limit. We discuss the best measurement schemes to protect the entanglement of the qubits. We also analyze the case of two qubits coupled to a common bath. Then, the average concurrence can vanish at discrete times and may coincide with the concurrence of the density matrix. The results explained in this article have been presented during the 'Fifth International Workshop DICE2010' by the first author and have been the subject of a prior publication.

  10. 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.

  11. Technical description of the RIVM trajectory model

    Energy Technology Data Exchange (ETDEWEB)

    De Waal, E.S.; Van Pul, W.A.J.

    1995-12-01

    The RIVM trajectory model, described in this report, enables calculation of a backward or forward trajectory. These trajectories are used to `follow` previous released air pollution in a backward mode or to `find` the origin of air pollution in a forward mode. The trajectories are used in the smog forecasting and in the TREND model for the distribution of materials in Europe. Presently 6-hourly ECMWF wind fields at 1000 and 850 hPa, with 3 deg x 3 deg latitude-longitude resolution are used. Wind fields with a different resolution in latitude-longitude can also be used after simple adjustments. An iterative method, described elsewhere, is applied to calculate the trajectories. Within limits, the user is free to choose the time step (1, 2 or 6-hour), transport height, length, starting or arrival date and starting or arrival position of the trajectory. The differences between the trajectories calculated with time steps of 1, 2 and 6 h were small. For the 96-hour trajectories at 1000 and 850 hPa the deviations were generally within 1 deg latitude and longitude, i.e. 100-200 km. The trajectory calculated with the 6-hour time step could be used without a great loss in accuracy compared to the calculations with the 1-hour time step. A typical error in the trajectory path at 1000 and 850 hPa was 500 km, which is about 30% of a typical travel distance. However, close to quickly changing weather systems, such as cyclones, the error can be as large as the travel distance and makes the calculations unreliable. The error in the forecasted trajectory was found to be larger than the above error estimation due to larger uncertainties in the forecasted compared to the analyzed wind fields. A manual on how to run the model is also given. 5 figs., 3 tabs., 5 refs., 6 appendices

  12. Parallel trajectory similarity joins in spatial networks

    KAUST Repository

    Shang, Shuo

    2018-04-04

    The matching of similar pairs of objects, called similarity join, is fundamental functionality in data management. We consider two cases of trajectory similarity joins (TS-Joins), including a threshold-based join (Tb-TS-Join) and a top-k TS-Join (k-TS-Join), where the objects are trajectories of vehicles moving in road networks. Given two sets of trajectories and a threshold θ, the Tb-TS-Join returns all pairs of trajectories from the two sets with similarity above θ. In contrast, the k-TS-Join does not take a threshold as a parameter, and it returns the top-k most similar trajectory pairs from the two sets. The TS-Joins target diverse applications such as trajectory near-duplicate detection, data cleaning, ridesharing recommendation, and traffic congestion prediction. With these applications in mind, we provide purposeful definitions of similarity. To enable efficient processing of the TS-Joins on large sets of trajectories, we develop search space pruning techniques and enable use of the parallel processing capabilities of modern processors. Specifically, we present a two-phase divide-and-conquer search framework that lays the foundation for the algorithms for the Tb-TS-Join and the k-TS-Join that rely on different pruning techniques to achieve efficiency. For each trajectory, the algorithms first find similar trajectories. Then they merge the results to obtain the final result. The algorithms for the two joins exploit different upper and lower bounds on the spatiotemporal trajectory similarity and different heuristic scheduling strategies for search space pruning. Their per-trajectory searches are independent of each other and can be performed in parallel, and the mergings have constant cost. An empirical study with real data offers insight in the performance of the algorithms and demonstrates that they are capable of outperforming well-designed baseline algorithms by an order of magnitude.

  13. Parallel trajectory similarity joins in spatial networks

    KAUST Repository

    Shang, Shuo; Chen, Lisi; Wei, Zhewei; Jensen, Christian S.; Zheng, Kai; Kalnis, Panos

    2018-01-01

    The matching of similar pairs of objects, called similarity join, is fundamental functionality in data management. We consider two cases of trajectory similarity joins (TS-Joins), including a threshold-based join (Tb-TS-Join) and a top-k TS-Join (k-TS-Join), where the objects are trajectories of vehicles moving in road networks. Given two sets of trajectories and a threshold θ, the Tb-TS-Join returns all pairs of trajectories from the two sets with similarity above θ. In contrast, the k-TS-Join does not take a threshold as a parameter, and it returns the top-k most similar trajectory pairs from the two sets. The TS-Joins target diverse applications such as trajectory near-duplicate detection, data cleaning, ridesharing recommendation, and traffic congestion prediction. With these applications in mind, we provide purposeful definitions of similarity. To enable efficient processing of the TS-Joins on large sets of trajectories, we develop search space pruning techniques and enable use of the parallel processing capabilities of modern processors. Specifically, we present a two-phase divide-and-conquer search framework that lays the foundation for the algorithms for the Tb-TS-Join and the k-TS-Join that rely on different pruning techniques to achieve efficiency. For each trajectory, the algorithms first find similar trajectories. Then they merge the results to obtain the final result. The algorithms for the two joins exploit different upper and lower bounds on the spatiotemporal trajectory similarity and different heuristic scheduling strategies for search space pruning. Their per-trajectory searches are independent of each other and can be performed in parallel, and the mergings have constant cost. An empirical study with real data offers insight in the performance of the algorithms and demonstrates that they are capable of outperforming well-designed baseline algorithms by an order of magnitude.

  14. Child personality facets and overreactive parenting as predictors of aggression and rule-breaking trajectories from childhood to adolescence.

    Science.gov (United States)

    Becht, Andrik I; Prinzie, Peter; Deković, Maja; van den Akker, Alithe L; Shiner, Rebecca L

    2016-05-01

    This study examined trajectories of aggression and rule breaking during the transition from childhood to adolescence (ages 9-15), and determined whether these trajectories were predicted by lower order personality facets, overreactive parenting, and their interaction. At three time points separated by 2-year intervals, mothers and fathers reported on their children's aggression and rule breaking (N = 290, M age = 8.8 years at Time 1). At Time 1, parents reported on their children's personality traits and their own overreactivity. Growth mixture modeling identified three aggression trajectories (low decreasing, high decreasing, and high increasing) and two rule-breaking trajectories (low and high). Lower optimism and compliance and higher energy predicted trajectories for both aggression and rule breaking, whereas higher expressiveness and irritability and lower orderliness and perseverance were unique risk factors for increasing aggression into adolescence. Lower concentration was a unique risk factor for increasing rule breaking. Parental overreactivity predicted higher trajectories of aggression but not rule breaking. Only two Trait × Overreactivity interactions were found. Our results indicate that personality facets could differentiate children at risk for different developmental trajectories of aggression and rule breaking.

  15. Developmental Education Evaluation Model.

    Science.gov (United States)

    Perry-Miller, Mitzi; And Others

    A developmental education evaluation model designed to be used at a multi-unit urban community college is described. The purpose of the design was to determine the cost effectiveness/worth of programs in order to initiate self-improvement. A needs assessment was conducted by interviewing and taping the responses of students, faculty, staff, and…

  16. Developmental paediatric anaesthetic pharmacology

    DEFF Research Database (Denmark)

    Hansen, Tom Giedsing

    2015-01-01

    Safe and effective drug therapy in neonates, infants and children require detailed knowledge about the ontogeny of drug disposition and action as well how these interact with genetics and co-morbidity of children. Recent advances in developmental pharmacology in children follow the increased...

  17. Trajectories of Sensation Seeking Among Puerto-Rican Children and Youth

    Science.gov (United States)

    Martins, Silvia S.; Wall, Melanie M.; Eisenberg, Ruth; Blanco, Carlos; Santaella, Julian; Ramos-Olazagasti, Maria; Canino, Glorisa; Bird, Hector R.; Brown, Qiana; Duarte, Cristiane S.

    2015-01-01

    Objective To document the natural course of sensation seeking from childhood to adolescence, characterize distinct sensation-seeking trajectories, and examine how these trajectories vary according to selected predictors. Method Data were obtained from the Boricua Youth Study, a longitudinal study of 2,491 children and adolescents of Puerto Rican background (three assessments from 2000 to 2004). First, age-specific sensation-seeking levels were characterized. Then, age-adjusted residuals were analyzed using growth mixture models (GMM). Results On average, sensation seeking was stable in childhood (ages 5–10) and increased during adolescence (ages 11–17). Mean scores of sensation seeking were higher in the South Bronx vs. Puerto Rico and among males vs. females. Four classes of sensation-seeking trajectories were observed: most study participants had age-expected sensation-seeking trajectories following the average for their age (“normative,” 43.8%); others (37.2%) remained consistently lower than the expected average for their age (“low” sensation seeking); some (12.0%) had an “accelerated” sensation-seeking trajectory, increasing at a faster rate than expected, while a minority (7.0%) had a decreasing sensation-seeking trajectory that started high but decreased, reaching scores slightly higher than the age-average sensation-seeking scores (“stabilizers”). Site (South Bronx vs. Puerto Rico) and gender were predictors of membership in a specific class of sensation-seeking trajectory. Conclusion It is important to take a developmental approach when examining sensation seeking and to consider gender and the social environment when trying to understand how sensation seeking evolves during childhood and adolescence. PMID:26598479

  18. Interoception and psychopathology: A developmental neuroscience perspective.

    Science.gov (United States)

    Murphy, Jennifer; Brewer, Rebecca; Catmur, Caroline; Bird, Geoffrey

    2017-02-01

    Interoception refers to the perception of the physiological condition of the body, including hunger, temperature, and heart rate. There is a growing appreciation that interoception is integral to higher-order cognition. Indeed, existing research indicates an association between low interoceptive sensitivity and alexithymia (a difficulty identifying one's own emotion), underscoring the link between bodily and emotional awareness. Despite this appreciation, the developmental trajectory of interoception across the lifespan remains under-researched, with clear gaps in our understanding. This qualitative review and opinion paper provides a brief overview of interoception, discussing its relevance for developmental psychopathology, and highlighting measurement issues, before surveying the available work on interoception across four stages of development: infancy, childhood, adolescence and late adulthood. Where gaps in the literature addressing the development of interoception exist, we draw upon the association between alexithymia and interoception, using alexithymia as a possible marker of atypical interoception. Evidence indicates that interoceptive ability varies across development, and that this variance correlates with established age-related changes in cognition and with risk periods for the development of psychopathology. We suggest a theory within which atypical interoception underlies the onset of psychopathology and risky behaviour in adolescence, and the decreased socio-emotional competence observed in late adulthood. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  19. Interoception and psychopathology: A developmental neuroscience perspective

    Directory of Open Access Journals (Sweden)

    Jennifer Murphy

    2017-02-01

    Full Text Available Interoception refers to the perception of the physiological condition of the body, including hunger, temperature, and heart rate. There is a growing appreciation that interoception is integral to higher-order cognition. Indeed, existing research indicates an association between low interoceptive sensitivity and alexithymia (a difficulty identifying one’s own emotion, underscoring the link between bodily and emotional awareness. Despite this appreciation, the developmental trajectory of interoception across the lifespan remains under-researched, with clear gaps in our understanding. This qualitative review and opinion paper provides a brief overview of interoception, discussing its relevance for developmental psychopathology, and highlighting measurement issues, before surveying the available work on interoception across four stages of development: infancy, childhood, adolescence and late adulthood. Where gaps in the literature addressing the development of interoception exist, we draw upon the association between alexithymia and interoception, using alexithymia as a possible marker of atypical interoception. Evidence indicates that interoceptive ability varies across development, and that this variance correlates with established age-related changes in cognition and with risk periods for the development of psychopathology. We suggest a theory within which atypical interoception underlies the onset of psychopathology and risky behaviour in adolescence, and the decreased socio-emotional competence observed in late adulthood.

  20. Trajectories of Intimate Partner Violence Victimization

    Directory of Open Access Journals (Sweden)

    Kevin M. Swartout

    2012-08-01

    Full Text Available Introduction: The purposes of this study were to assess the extent to which latent trajectories of female intimate partner violence (IPV victimization exist; and, if so, use negative childhood experiences to predict trajectory membership.Methods: We collected data from 1,575 women at 5 time-points regarding experiences during adolescence and their 4 years of college. We used latent class growth analysis to fit a series of personcentered, longitudinal models ranging from 1 to 5 trajectories. Once the best-fitting model was selected, we used negative childhood experience variables—sexual abuse, physical abuse, and witnessing domestic violence—to predict most-likely trajectory membership via multinomial logistic regression.Results: A 5-trajectory model best fit the data both statistically and in terms of interpretability. The trajectories across time were interpreted as low or no IPV, low to moderate IPV, moderate to low IPV, high to moderate IPV, and high and increasing IPV, respectively. Negative childhood experiences differentiated trajectory membership, somewhat, with childhood sexual abuse as a consistent predictor of membership in elevated IPV trajectories.Conclusion: Our analyses show how IPV risk changes over time and in different ways. These differential patterns of IPV suggest the need for prevention strategies tailored for women that consider victimization experiences in childhood and early adulthood. [West J Emerg Med. 2012;13(3:272–277.

  1. From the trajectory to the density memory

    International Nuclear Information System (INIS)

    Cakir, Rasit; Krokhin, Arkadii; Grigolini, Paolo

    2007-01-01

    In this paper we discuss the connection between trajectory and density memory. The first form of memory is a property of a stochastic trajectory, whose stationary correlation function shows that the fluctuation at a given time depends on the earlier fluctuations. The density memory is a property of a collection of trajectories, whose density time evolution is described by a time convoluted equation showing that the density time evolution depends on its past history. We show that the trajectory memory does not necessarily yields density memory, and that density memory might be compatible with the existence of abrupt jumps resetting to zero the system's memory. We focus our attention on a time-convoluted diffusion equation, when the memory kernel is an inverse power law with (i) negative and (ii) positive tail. In case (i) there exist both renewal trajectories and trajectories with memory, compatible with this equation. Case (ii), which has eluded so far a convincing interpretation in terms of trajectories, is shown to be compatible only with trajectory memory

  2. User oriented trajectory search for trip recommendation

    KAUST Repository

    Shang, Shuo; Ding, Ruogu; Yuan, Bo; Xie, Kexin; Zheng, Kai; Kalnis, Panos

    2012-01-01

    trajectory search by locations (spatial domain only), we consider both spatial and textual domains in the new UOTS query. Given a trajectory data set, the query input contains a set of intended places given by the traveler and a set of textual attributes

  3. Soccer Ball Lift Coefficients via Trajectory Analysis

    Science.gov (United States)

    Goff, John Eric; Carre, Matt J.

    2010-01-01

    We performed experiments in which a soccer ball was launched from a machine while two high-speed cameras recorded portions of the trajectory. Using the trajectory data and published drag coefficients, we extracted lift coefficients for a soccer ball. We determined lift coefficients for a wide range of spin parameters, including several spin…

  4. Complex trajectories in a classical periodic potential

    International Nuclear Information System (INIS)

    Anderson, Alexander G; Bender, Carl M

    2012-01-01

    This paper examines the complex trajectories of a classical particle in the potential V(x) = −cos (x). Almost all the trajectories describe a particle that hops from one well to another in an erratic fashion. However, it is shown analytically that there are two special classes of trajectories x(t) determined only by the energy of the particle and not by the initial position of the particle. The first class consists of periodic trajectories; that is, trajectories that return to their initial position x(0) after some real time T. The second class consists of trajectories for which there exists a real time T such that x(t + T) = x(t) ± 2π. These two classes of classical trajectories are analogous to valence and conduction bands in quantum mechanics, where the quantum particle either remains localized or else tunnels resonantly (conducts) through a crystal lattice. These two special types of trajectories are associated with sets of energies of measure 0. For other energies, it is shown that for long times the average velocity of the particle becomes a fractal-like function of energy. (paper)

  5. Complex trajectories in a classical periodic potential

    Science.gov (United States)

    Anderson, Alexander G.; Bender, Carl M.

    2012-11-01

    This paper examines the complex trajectories of a classical particle in the potential V(x) = -cos (x). Almost all the trajectories describe a particle that hops from one well to another in an erratic fashion. However, it is shown analytically that there are two special classes of trajectories x(t) determined only by the energy of the particle and not by the initial position of the particle. The first class consists of periodic trajectories; that is, trajectories that return to their initial position x(0) after some real time T. The second class consists of trajectories for which there exists a real time T such that x(t + T) = x(t) ± 2π. These two classes of classical trajectories are analogous to valence and conduction bands in quantum mechanics, where the quantum particle either remains localized or else tunnels resonantly (conducts) through a crystal lattice. These two special types of trajectories are associated with sets of energies of measure 0. For other energies, it is shown that for long times the average velocity of the particle becomes a fractal-like function of energy.

  6. Ontogenetic trajectories of chimpanzee social play: similarities with humans.

    Directory of Open Access Journals (Sweden)

    Giada Cordoni

    Full Text Available Social play, a widespread phenomenon in mammals, is a multifunctional behavior, which can have many different roles according to species, sex, age, relationship quality between playmates, group membership, context, and habitat. Play joins and cuts across a variety of disciplines leading directly to inquiries relating to individual developmental changes and species adaptation, thus the importance of comparative studies appears evident. Here, we aim at proposing a possible ontogenetic pathway of chimpanzee play (Pan troglodytes and contrast our data with those of human play. Chimpanzee play shows a number of changes from infancy to juvenility. Particularly, solitary and social play follows different developmental trajectories. While solitary play peaks in infancy, social play does not show any quantitative variation between infancy and juvenility but shows a strong qualitative variation in complexity, asymmetry, and playmate choice. Like laughter in humans, the playful expressions in chimpanzees (at the different age phases seem to have a role in advertising cooperative dispositions and intentions thus increasing the likelihood of engaging in solid social relationships. In conclusion, in chimpanzees, as in humans, both play behavior and the signals that accompany play serve multiple functions according to the different age phases.

  7. Inattention/hyperactivity and aggression from early childhood to adolescence: heterogeneity of trajectories and differential influence of family environment characteristics.

    Science.gov (United States)

    Jester, Jennifer M; Nigg, Joel T; Adams, Kenneth; Fitzgerald, Hiram E; Puttler, Leon I; Wong, Maria M; Zucker, Robert A

    2005-01-01

    Inattention/hyperactivity and aggressive behavior problems were measured in 335 children from school entry throughout adolescence, at 3-year intervals. Children were participants in a high-risk prospective study of substance use disorders and comorbid problems. A parallel process latent growth model found aggressive behavior decreasing throughout childhood and adolescence, whereas inattentive/hyperactive behavior levels were constant. Growth mixture modeling, in which developmental trajectories are statistically classified, found two classes for inattention/hyperactivity and two for aggressive behavior, resulting in a total of four trajectory classes. Different influences of the family environment predicted development of the two types of behavior problems when the other behavior problem was held constant. Lower emotional support and lower intellectual stimulation by the parents in early childhood predicted membership in the high problem class of inattention/hyperactivity when the trajectory of aggression was held constant. Conversely, conflict and lack of cohesiveness in the family environment predicted membership in a worse developmental trajectory of aggressive behavior when the inattention/hyperactivity trajectories were held constant. The implications of these findings for the development of inattention/hyperactivity and for the development of risk for the emergence of substance use disorders are discussed.

  8. The power of a single trajectory

    Science.gov (United States)

    Schnellbächer, Nikolas D.; Schwarz, Ulrich S.

    2018-03-01

    Random walks are often evaluated in terms of their mean squared displacements, either for a large number of trajectories or for one very long trajectory. An alternative evaluation is based on the power spectral density, but here it is less clear which information can be extracted from a single trajectory. For continuous-time Brownian motion, Krapf et al now have mathematically proven that the one property that can be reliably extracted from a single trajectory is the frequency dependence of the ensemble-averaged power spectral density (Krapf et al 2018 New J. Phys. 20 023029). Their mathematical analysis also identifies the appropriate frequency window for this procedure and shows that the diffusion coefficient can be extracted by averaging over a small number of trajectories. The authors have verified their analytical results both by computer simulations and experiments.

  9. Picking Robot Arm Trajectory Planning Method

    Directory of Open Access Journals (Sweden)

    Zhang Zhiyong

    2014-01-01

    Full Text Available The picking robot arm is scheduled to complete picking tasks in the working space, to overcome the shaking vibration to improve the picking stability, its movement should follow specific consistence trajectory points. Usually we should give definite multiple feature picking points, map their inverse kinematics to the joint space, establish motion equation for the corresponding point in the joint space, then follow these equations motion for the interpolation on the joint so that we can meet the movement requirements. Trajectory planning is decisive significance for accuracy and stability of controlling robot arm. The key issue that picking arm complete picking task will be come true by trajectory planning, namely, robot arm track the desired trajectory. which based on kinematics and statics picking analysis in a joint space according to the requirements of picking tasks, and obtain the position and orientation for picking robot arm, study and calculate the theory of trajectory parameters timely.

  10. Trajectories of delinquency and parenting styles.

    Science.gov (United States)

    Hoeve, Machteld; Blokland, Arjan; Dubas, Judith Semon; Loeber, Rolf; Gerris, Jan R M; van der Laan, Peter H

    2008-02-01

    We investigated trajectories of adolescent delinquent development using data from the Pittsburgh Youth Study and examined the extent to which these different trajectories are differentially predicted by childhood parenting styles. Based on self-reported and official delinquency seriousness, covering ages 10-19, we identified five distinct delinquency trajectories differing in both level and change in seriousness over time: a nondelinquent, minor persisting, moderate desisting, serious persisting, and serious desisting trajectory. More serious delinquents tended to more frequently engage in delinquency, and to report a higher proportion of theft. Proportionally, serious persistent delinquents were the most violent of all trajectory groups. Using cluster analysis we identified three parenting styles: authoritative, authoritarian (moderately supportive), and neglectful (punishing). Controlling for demographic characteristics and childhood delinquency, neglectful parenting was more frequent in moderate desisters, serious persisters, and serious desisters, suggesting that parenting styles differentiate non- or minor delinquents from more serious delinquents.

  11. Path-based Queries on Trajectory Data

    DEFF Research Database (Denmark)

    Krogh, Benjamin Bjerre; Pelekis, Nikos; Theodoridis, Yannis

    2014-01-01

    In traffic research, management, and planning a number of path-based analyses are heavily used, e.g., for computing turn-times, evaluating green waves, or studying traffic flow. These analyses require retrieving the trajectories that follow the full path being analyzed. Existing path queries cannot...... sufficiently support such path-based analyses because they retrieve all trajectories that touch any edge in the path. In this paper, we define and formalize the strict path query. This is a novel query type tailored to support path-based analysis, where trajectories must follow all edges in the path...... a specific path by only retrieving data from the first and last edge in the path. To correctly answer strict path queries existing network-constrained trajectory indexes must retrieve data from all edges in the path. An extensive performance study of NETTRA using a very large real-world trajectory data set...

  12. Task Decomposition Module For Telerobot Trajectory Generation

    Science.gov (United States)

    Wavering, Albert J.; Lumia, Ron

    1988-10-01

    A major consideration in the design of trajectory generation software for a Flight Telerobotic Servicer (FTS) is that the FTS will be called upon to perform tasks which require a diverse range of manipulator behaviors and capabilities. In a hierarchical control system where tasks are decomposed into simpler and simpler subtasks, the task decomposition module which performs trajectory planning and execution should therefore be able to accommodate a wide range of algorithms. In some cases, it will be desirable to plan a trajectory for an entire motion before manipulator motion commences, as when optimizing over the entire trajectory. Many FTS motions, however, will be highly sensory-interactive, such as moving to attain a desired position relative to a non-stationary object whose position is periodically updated by a vision system. In this case, the time-varying nature of the trajectory may be handled either by frequent replanning using updated sensor information, or by using an algorithm which creates a less specific state-dependent plan that determines the manipulator path as the trajectory is executed (rather than a priori). This paper discusses a number of trajectory generation techniques from these categories and how they may be implemented in a task decompo-sition module of a hierarchical control system. The structure, function, and interfaces of the proposed trajectory gener-ation module are briefly described, followed by several examples of how different algorithms may be performed by the module. The proposed task decomposition module provides a logical structure for trajectory planning and execution, and supports a large number of published trajectory generation techniques.

  13. Personalized trajectory matching in spatial networks

    KAUST Repository

    Shang, Shuo

    2013-07-31

    With the increasing availability of moving-object tracking data, trajectory search and matching is increasingly important. We propose and investigate a novel problem called personalized trajectory matching (PTM). In contrast to conventional trajectory similarity search by spatial distance only, PTM takes into account the significance of each sample point in a query trajectory. A PTM query takes a trajectory with user-specified weights for each sample point in the trajectory as its argument. It returns the trajectory in an argument data set with the highest similarity to the query trajectory. We believe that this type of query may bring significant benefits to users in many popular applications such as route planning, carpooling, friend recommendation, traffic analysis, urban computing, and location-based services in general. PTM query processing faces two challenges: how to prune the search space during the query processing and how to schedule multiple so-called expansion centers effectively. To address these challenges, a novel two-phase search algorithm is proposed that carefully selects a set of expansion centers from the query trajectory and exploits upper and lower bounds to prune the search space in the spatial and temporal domains. An efficiency study reveals that the algorithm explores the minimum search space in both domains. Second, a heuristic search strategy based on priority ranking is developed to schedule the multiple expansion centers, which can further prune the search space and enhance the query efficiency. The performance of the PTM query is studied in extensive experiments based on real and synthetic trajectory data sets. © 2013 Springer-Verlag Berlin Heidelberg.

  14. Trajectory Specification for Automation of Terminal Air Traffic Control

    Science.gov (United States)

    Paielli, Russell A.

    2016-01-01

    "Trajectory specification" is the explicit bounding and control of aircraft tra- jectories such that the position at each point in time is constrained to a precisely defined volume of space. The bounding space is defined by cross-track, along-track, and vertical tolerances relative to a reference trajectory that specifies position as a function of time. The tolerances are dynamic and will be based on the aircraft nav- igation capabilities and the current traffic situation. A standard language will be developed to represent these specifications and to communicate them by datalink. Assuming conformance, trajectory specification can guarantee safe separation for an arbitrary period of time even in the event of an air traffic control (ATC) sys- tem or datalink failure, hence it can help to achieve the high level of safety and reliability needed for ATC automation. As a more proactive form of ATC, it can also maximize airspace capacity and reduce the reliance on tactical backup systems during normal operation. It applies to both enroute airspace and the terminal area around airports, but this paper focuses on arrival spacing in the terminal area and presents ATC algorithms and software for achieving a specified delay of runway arrival time.

  15. Normal Pressure Hydrocephalus (NPH)

    Science.gov (United States)

    ... local chapter Join our online community Normal Pressure Hydrocephalus (NPH) Normal pressure hydrocephalus is a brain disorder ... Symptoms Diagnosis Causes & risks Treatments About Normal Pressure Hydrocephalus Normal pressure hydrocephalus occurs when excess cerebrospinal fluid ...

  16. Developmental risk factors in Vietnamese preschool-age children: Cross-sectional survey.

    Science.gov (United States)

    Duc, Nguyen Huu Chau

    2016-01-01

    Early childhood development (ECD) strongly influences children's basic learning, school success, economic participation, social citizenry and health. Although some risk factors related to childhood development are documented, further exploration is necessary considering various sociodemographic, nutritional, and psychosocial factors. This study investigated factors affecting ECD in Vietnamese preschoolers. We used data from the representative, cross-sectional round of the Vietnam Multiple Indicator Clusters Survey 2011. Early Childhood Development Index questionnaires were administered to mothers of all children aged 36-59 months in the household (n = 1459). Descriptive statistics and multivariate logistic regression were used in the analysis. In Vietnam, 17.2% of children did not reach their full developmental potential within the first 5 years. Children who had been breast-fed (AOR, 2.78; 95%CI: 1.28-6.02), attended preschool (AOR, 1.75; 95%CI: 1.28-2.39), were of major ethnicity (AOR, 2.41; 95%CI: 1.55-3.74), had a mother with secondary or higher education (AOR, 1.69; 95%CI: 1.19-2.38) and had relatives who engaged with them in four or more activities that promote learning (AOR, 1.55; 95%CI: 1.13-2.14) were more likely to have a normal developmental trajectory. Furthermore, children who experienced physical punishment and stunting were 0.69-fold (95%CI: 0.51-0.95) and 0.71-fold (95%CI: 0.51-0.98) less likely to be on track for ECD, respectively. The risk factors associated with delayed ECD were low level of maternal education; family ethnicity; lack of preschool attendance; relatives who did not engage with them in learning; physical punishment; not being breast-fed; and stunting. © 2015 Japan Pediatric Society.

  17. Influence of the Friction Coefficient on the Trajectory Performance for a Car-Like Robot

    Directory of Open Access Journals (Sweden)

    Francisco Valero

    2017-01-01

    Full Text Available A collision-free trajectory planner for a car-like mobile robot moving in complex environments is introduced and the influence of the coefficient of friction on important working parameters is analyzed. The proposed planner takes into account not only the dynamic capabilities of the robot but also the behaviour of the tire. This planner is based on sequential quadratic programming algorithms and the normalized time method. Different values for the coefficient of friction have been taken following a normal Gaussian distribution to see its influence on the working parameters. The algorithm has been applied to several examples and the results show that computation times are compatible with real-time work, so the authors call them efficient generated trajectories as they avoid collisions. Besides, working parameters such as the minimum trajectory time, the maximum vehicle speed, computational time, and consumed energy have been monitored and some conclusions have been reached.

  18. EGUN, Charged Particle Trajectories in Electromagnetic Focusing System

    International Nuclear Information System (INIS)

    Herrmannsfeldt, W.B.

    2002-01-01

    1 - Description of problem or function: EGUN computes trajectories of charged particles in electrostatic and magnetostatic focusing systems including the effects of space charge and self-magnetic fields. Starting options include Child's Law conditions on cathodes of various shapes, user-specified conditions input for each ray, and a combination of Child's Law conditions and user specifications. Either rectangular or cylindrically symmetric geometry may be used. Magnetic fields may be specified using an arbitrary configuration of coils, or the output of a magnet program, such as Poisson, or by an externally calculated array of the axial fields. 2 - Method of solution: The program first solves Laplace's equation. Next, the first iteration of electron trajectories is started using one of the four starting options. On the first iteration cycle, space charge forces are calculated from the assumption of paraxial flow. As the rays are traced, space charge is computed and stored. After all the electron trajectories have been calculated, the program begins the second cycle by solving the Poisson equation with the space charge from the first iteration. Subsequent iteration cycles follow this pattern. The Poisson equation is solved by an alternate column relaxation technique known as the semi-iterative Chebyshev method. A fourth-order Runge-Kutta method is used to solve the relativistic differential equations of the trajectory calculations. 3 - Restrictions on the complexity of the problem - Maxima of: 9001 mesh points in a square mesh, 300 mesh points in the axial direction, 100 mesh points in the radial direction, 101 potentials, 51 rays. In the cylindrical coordinates, the magnetic fields are axially symmetric. In rectangular coordinates, the external field is assumed to be normal to the plane of the problem, which is assumed to be the median plane

  19. NIDCAP and developmental care

    Directory of Open Access Journals (Sweden)

    Dominique Haumont

    2014-06-01

    Full Text Available Perinatal mortality in very low birth weight infants has dramatically decreased during the last decades. However, 15-25% of these infants will show neurodevelopmental impairment later on. The aim of implementing early developmental care (EDC, emerged as a new field in neonatology, is to create an intervention program designed to provide support for optimal neurobehavioral development during this highly vulnerable period of brain growth. The theoretical framework, which underlies the approach, is supported by research in different scientific fields, including neuroscience, psychology, medicine and nursing. EDC utilizes a range of medical and nursing interventions that aim to decrease the stress of preterm neonates in neonatal intensive care units (NICUs. The Neonatal Individualized Developmental Care Assessment Program (NIDCAP is an integrated and holistic form of family-centered developmental care. Changing the traditional NICU towards an EDC-NICU includes training nursing and medical staff, investing in their quality and most importantly keeping parents in proximity to the infants. The new challenge of modern neonatology is to restore the mother-infant dyad applying “couplet care” starting at birth until discharge. Most of the European NICUs apply some elements of EDC, but it is more consistent in northern Europe. The development of NIDCAP training centers in Europe demonstrates the evolution of care. It is likely that future research and intervention programs will optimize our practices. Developmental care could prove to be an important recent step in improving outcome in extremely preterm neonates. Proceedings of the 10th International Workshop on Neonatology · Cagliari (Italy · October 22nd-25th, 2014 · The last ten years, the next ten years in Neonatology Guest Editors: Vassilios Fanos, Michele Mussap, Gavino Faa, Apostolos Papageorgiou

  20. Evolutionary and developmental modules.

    Science.gov (United States)

    Lacquaniti, Francesco; Ivanenko, Yuri P; d'Avella, Andrea; Zelik, Karl E; Zago, Myrka

    2013-01-01

    The identification of biological modules at the systems level often follows top-down decomposition of a task goal, or bottom-up decomposition of multidimensional data arrays into basic elements or patterns representing shared features. These approaches traditionally have been applied to mature, fully developed systems. Here we review some results from two other perspectives on modularity, namely the developmental and evolutionary perspective. There is growing evidence that modular units of development were highly preserved and recombined during evolution. We first consider a few examples of modules well identifiable from morphology. Next we consider the more difficult issue of identifying functional developmental modules. We dwell especially on modular control of locomotion to argue that the building blocks used to construct different locomotor behaviors are similar across several animal species, presumably related to ancestral neural networks of command. A recurrent theme from comparative studies is that the developmental addition of new premotor modules underlies the postnatal acquisition and refinement of several different motor behaviors in vertebrates.

  1. Tracers vs. trajectories in a coastal region

    Science.gov (United States)

    Engqvist, A.; Döös, K.

    2008-12-01

    Two different methods of estimating the water exchange through a Baltic coastal region have been used, consisting of particle trajectories and passive tracers. Water is traced from and to a small discharge region near the coast. The discharge material in this region is treated as zero dimensional particles or tracers with neutral buoyancy. The real discharge material could be a leakage of radio-nuclides through the sea floor from an underground repository of nuclear waste. Water exchange rates between the discharge region and the model domain are estimated using both forward and backward trajectories as well as passive tracers. The Lagrangian trajectories can account for the time evolution of the water exchange while the tracers give one average age per model grid box. Water exchange times such as residence time, age and transient times have been calculated with trajectories but only the average age (AvA) for tracers. The trajectory calculations provide a more detailed time evolution than the tracers. On the other hand the tracers are integrated "on-line" simultaneously in the sea circulation model with the same time step while the Lagrangian trajectories are integrated "off-line" from the stored model velocities with its inherent temporal resolution, presently one hour. The sub-grid turbulence is parameterised as a Laplacian diffusion for the passive tracers and with an extra stochastic velocity for trajectories. The importance of the parameterised sub-grid turbulence for the trajectories is estimated to give an extra diffusion of the same order as the Laplacian diffusion by comparing the Lagrangian dispersions with and without parameterisation. The results of the different methods are similar but depend on the chosen diffusivity coefficient with a slightly higher correlation between trajectories and tracers when integrated with a lower diffusivity coefficient.

  2. Path integrals and geometry of trajectories

    International Nuclear Information System (INIS)

    Blau, M.; Keski-Vakkuri, E.; Niemi, A.J.

    1990-01-01

    A geometrical interpretation of path integrals is developed in the space of trajectories. This yields a supersymmetric formulation of a generic path integral, with the supersymmetry resembling the BRST supersymmetry of a first class constrained system. If the classical equation of motion is a Killing vector field in the space of trajectories, the supersymmetry localizes the path integral to classical trajectories and the WKB approximation becomes exact. This can be viewed as a path integral generalization of the Duistermaat-Heckman theorem, which states the conditions for the exactness of the WKB approximation for integrals in a compact phase space. (orig.)

  3. An Examination of "The Martian" Trajectory

    Science.gov (United States)

    Burke, Laura

    2015-01-01

    This analysis was performed to support a request to examine the trajectory of the Hermes vehicle in the novel "The Martian" by Andy Weir. Weir developed his own tool to perform the analysis necessary to provide proper trajectory information for the novel. The Hermes vehicle is the interplanetary spacecraft that shuttles the crew to and from Mars. It is notionally a Nuclear powered vehicle utilizing VASIMR engines for propulsion. The intent of this analysis was the determine whether the trajectory as it was outlined in the novel is consistent with the rules of orbital mechanics.

  4. Soccer ball lift coefficients via trajectory analysis

    International Nuclear Information System (INIS)

    Goff, John Eric; Carre, Matt J

    2010-01-01

    We performed experiments in which a soccer ball was launched from a machine while two high-speed cameras recorded portions of the trajectory. Using the trajectory data and published drag coefficients, we extracted lift coefficients for a soccer ball. We determined lift coefficients for a wide range of spin parameters, including several spin parameters that have not been obtained by today's wind tunnels. Our trajectory analysis technique is not only a valuable tool for professional sports scientists, it is also accessible to students with a background in undergraduate-level classical mechanics.

  5. Soccer ball lift coefficients via trajectory analysis

    Energy Technology Data Exchange (ETDEWEB)

    Goff, John Eric [Department of Physics, Lynchburg College, Lynchburg, VA 24501 (United States); Carre, Matt J, E-mail: goff@lynchburg.ed [Department of Mechanical Engineering, University of Sheffield, Sheffield S1 3JD (United Kingdom)

    2010-07-15

    We performed experiments in which a soccer ball was launched from a machine while two high-speed cameras recorded portions of the trajectory. Using the trajectory data and published drag coefficients, we extracted lift coefficients for a soccer ball. We determined lift coefficients for a wide range of spin parameters, including several spin parameters that have not been obtained by today's wind tunnels. Our trajectory analysis technique is not only a valuable tool for professional sports scientists, it is also accessible to students with a background in undergraduate-level classical mechanics.

  6. Helicopter trajectory planning using optimal control theory

    Science.gov (United States)

    Menon, P. K. A.; Cheng, V. H. L.; Kim, E.

    1988-01-01

    A methodology for optimal trajectory planning, useful in the nap-of-the-earth guidance of helicopters, is presented. This approach uses an adjoint-control transformation along with a one-dimensional search scheme for generating the optimal trajectories. In addition to being useful for helicopter nap-of-the-earth guidance, the trajectory planning solution is of interest in several other contexts, such as robotic vehicle guidance and terrain-following guidance for cruise missiles and aircraft. A distinguishing feature of the present research is that the terrain constraint and the threat envelopes are incorporated in the equations of motion. Second-order necessary conditions are examined.

  7. Normalization: A Preprocessing Stage

    OpenAIRE

    Patro, S. Gopal Krishna; Sahu, Kishore Kumar

    2015-01-01

    As we know that the normalization is a pre-processing stage of any type problem statement. Especially normalization takes important role in the field of soft computing, cloud computing etc. for manipulation of data like scale down or scale up the range of data before it becomes used for further stage. There are so many normalization techniques are there namely Min-Max normalization, Z-score normalization and Decimal scaling normalization. So by referring these normalization techniques we are ...

  8. Active Transportation Demand Management (ATDM) Trajectory Level Validation

    Data.gov (United States)

    Department of Transportation — The ATDM Trajectory Validation project developed a validation framework and a trajectory computational engine to compare and validate simulated and observed vehicle...

  9. Low Thrust Trajectory Design for GSFC Missions Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Evolutionary Mission Trajectory Generator (EMTG) is a global trajectory optimization tool. EMTG is intended for use in designing interplanetary missions which...

  10. Developmental trends in the facilitation of multisensory objects with distractors

    Directory of Open Access Journals (Sweden)

    Harriet eDowning

    2015-01-01

    Full Text Available Sensory integration and the ability to discriminate target objects from distractors are critical to survival, yet the developmental trajectories of these abilities are unknown. This study investigated developmental changes in 9- (n=18 and 11-year-old (n=20 children, adolescents (n=19 and adults (n=22 using an audiovisual object discrimination task with uni- and multisensory distractors. Reaction times (RTs were slower with visual/audiovisual distractors, and although all groups demonstrated facilitation of multisensory RTs in these conditions, children’s and adolescents’ responses corresponded to fewer race model violations than adults’, suggesting protracted maturation of multisensory processes. Multisensory facilitation could not be explained by changes in RT variability, suggesting that tests of race model violations may still have theoretical value at least for familiar multisensory stimuli.

  11. Psychopathy: Developmental Perspectives and their Implications for Treatment

    Science.gov (United States)

    Anderson, Nathaniel E.; Kiehl, Kent A.

    2015-01-01

    Psychopathy is a neuropsychiatric disorder marked by deficient emotional responses, lack of empathy, and poor behavioral controls, commonly resulting in persistent antisocial deviance and criminal behavior. Accumulating research suggests that psychopathy follows a developmental trajectory with strong genetic influences, and which precipitates deleterious effects on widespread functional networks, particularly within paralimbic regions of the brain. While traditional therapeutic interventions commonly administered in prisons and forensic institutions have been notoriously ineffective at combating these outcomes, alternative strategies informed by an understanding of these specific neuropsychological obstacles to healthy development, and which target younger individuals with nascent symptoms of psychopathy are more promising. Here we review recent neuropsychiatric and neuroimaging literature that informs our understanding of the brain systems compromised in psychopathy, and apply these data to a broader understanding of its developmental course, ultimately promoting more proactive intervention strategies profiting from adaptive neuroplasticity in youth. PMID:23542910

  12. Developmental milestones record

    Science.gov (United States)

    Growth milestones for children; Normal childhood growth milestones; Childhood growth milestones ... activity in response Walks while holding on to furniture or other support Toddler -- 1 to 3 years ...

  13. Differential Neurodevelopmental Trajectories in Patients With Early-Onset Bipolar and Schizophrenia Disorders

    Science.gov (United States)

    Arango, Celso

    2014-01-01

    Schizophrenia and bipolar disorders share not only clinical features but also some risk factors such as genetic markers and childhood adversity, while other risk factors such as urbanicity and obstetric complications seem to be specific to schizophrenia. An intriguing question is whether the well-established abnormal neurodevelopment present in many children and adolescents who eventually develop schizophrenia is also present in bipolar patients. The literature on adult bipolar patients is controversial. We report data on a subgroup of patients with pediatric-onset psychotic bipolar disorder who seem to share some developmental trajectories with patients with early-onset schizophrenia. These early-onset psychotic bipolar patients have low intelligence quotient, more neurological signs, reduced frontal gray matter at the time of their first psychotic episode, and greater brain changes than healthy controls in a pattern similar to early-onset schizophrenia cases. However, patients with early-onset schizophrenia seem to have more social impairment, developmental abnormalities (eg, language problems), and lower academic achievement in childhood than early-onset bipolar patients. We suggest that some of these abnormal developmental trajectories are more related to the phenotypic features (eg, early-onset psychotic symptoms) of these 2 syndromes than to categorically defined Diagnostic and Statistical Manual of Mental Disorders disorders. PMID:24371326

  14. Trajectories of autonomy development across the adolescent transition in children with spina bifida.

    Science.gov (United States)

    Friedman, Deborah; Holmbeck, Grayson N; DeLucia, Christian; Jandasek, Barbara; Zebracki, Kathy

    2009-02-01

    The current study investigated individual growth in autonomy development across the adolescent transition, comparing the trajectories of children with and without spina bifida. Individual growth curve modeling procedures were utilized to describe the developmental course of autonomy across four waves of data collection, from ages 9 to 15, and to test whether illness status [spina bifida vs. matched comparison group (N = 68 for both groups at Time 1)] would significantly predict individual variability in autonomy development. Potential moderators [child gender, SES, and Peabody Picture Vocabulary Test (PPVT) score] of the association between illness status and autonomy development were also examined. Children with spina bifida demonstrated distinct developmental trajectories, though the nature of the group differences varied by type of autonomy development (emotional vs. behavioral), context (i.e. school vs. family), and reporter. Significant interactions with PPVT score and child gender were found. Overall, children with spina bifida show considerable developmental resiliency, but may lag behind their peers in specific areas of autonomy. Boys with spina bifida, and children with spina bifida who have lower than average levels of verbal intelligence, appear to be at greater risk for exhibiting delays in autonomy development.

  15. Trajectories of Suicidal Ideation from Sixth through Tenth Grades in Predicting Suicide Attempts in Young Adulthood in an Urban African American Cohort.

    Science.gov (United States)

    Musci, Rashelle J; Hart, Shelley R; Ballard, Elizabeth D; Newcomer, Alison; Van Eck, Kathryn; Ialongo, Nicholas; Wilcox, Holly

    2016-06-01

    The trajectory of suicidal ideation across early adolescence may inform the timing of suicide prevention program implementation. This study aimed to identify developmental trajectories of suicidal ideation among an urban cohort of community-residing African Americans (AA) longitudinally followed from middle school through early adulthood (ages 11-19 years). Subtypes based on the developmental course of suicidal ideation from late childhood through mid-adolescence were identified using longitudinal latent class analysis (LLCA) with 581 AA adolescents (52.7% male; 71.1% free or reduced school meals). The developmental trajectories of suicidal ideation were then used to predict suicide attempts in young adulthood. Our LLCA indicated two subtypes (i.e., ideators and nonideators), with 8% of the sample in the ideator class. This trajectory class shows a peak of suicidal ideation in seventh grade and a steady decline in ideation in subsequent grades. Additionally, suicidal ideation trajectories significantly predicted suicide attempt. Results of these analyses suggest the need for suicide prevention approaches prior to high school for AA youth. © 2015 The American Association of Suicidology.

  16. Everyday trajectories of hearing correction

    DEFF Research Database (Denmark)

    Lykke Hindhede, Anette

    2010-01-01

    wearers in order to rehabilitate them back to ‘normal'. However, within audiological research, noncompliance has attracted much attention as investigations have shown that more than 20 percent of hearing aids are very seldom, if ever, in use and 19 percent are used only occasionally. As shown in the paper...... are complex and epistemologically contested and can help explain why noncompliance is dominant when it comes to hearing rehabilitation for hearing impaired adults....

  17. Leveraging Chaos in Continuous Thrust Trajectory Design

    Data.gov (United States)

    National Aeronautics and Space Administration — A trajectory design tool is sought to leverage chaos and nonlinear dynamics present in multi-body gravitational fields to design ultra-low energy transfer...

  18. Age trajectories of stroke case fatality

    DEFF Research Database (Denmark)

    Olsen, Tom Skyhøj; Andersen, Zorana Jovanovic; Andersen, Klaus Kaae

    2011-01-01

    Mortality rates level off at older ages. Age trajectories of stroke case-fatality rates were studied with the aim of investigating prevalence of this phenomenon, specifically in case-fatality rates at older ages....

  19. Highly Accurate Measurement of Projectile Trajectories

    National Research Council Canada - National Science Library

    Leathem, J

    1997-01-01

    .... The method has been extensively used for free flight testing of weapon models. This report describes the on board instrumentation, the range instrumentation and the experimental procedure used to carry out the trajectory measurements...

  20. Analytical Ballistic Trajectories with Approximately Linear Drag

    Directory of Open Access Journals (Sweden)

    Giliam J. P. de Carpentier

    2014-01-01

    Full Text Available This paper introduces a practical analytical approximation of projectile trajectories in 2D and 3D roughly based on a linear drag model and explores a variety of different planning algorithms for these trajectories. Although the trajectories are only approximate, they still capture many of the characteristics of a real projectile in free fall under the influence of an invariant wind, gravitational pull, and terminal velocity, while the required math for these trajectories and planners is still simple enough to efficiently run on almost all modern hardware devices. Together, these properties make the proposed approach particularly useful for real-time applications where accuracy and performance need to be carefully balanced, such as in computer games.

  1. Trajectory Clustering with Applications to Airspace Monitoring

    Data.gov (United States)

    National Aeronautics and Space Administration — This paper presents a framework aimed at monitoring the behavior of aircraft in a given airspace. Trajectories that constitute typical operations are determined and...

  2. Trajectory behaviour at different phonemic context sizes

    CSIR Research Space (South Africa)

    Badenhorst, J

    2011-11-01

    Full Text Available The authors propose a piecewise-linear model for the temporal trajectories of Mel Frequency Cepstral Coefficients during phone transitions. As with conventional Hidden Markov Models, the parameters of the model can be estimated for different...

  3. Trajectory tracking control for underactuated stratospheric airship

    Science.gov (United States)

    Zheng, Zewei; Huo, Wei; Wu, Zhe

    2012-10-01

    Stratospheric airship is a new kind of aerospace system which has attracted worldwide developing interests for its broad application prospects. Based on the trajectory linearization control (TLC) theory, a novel trajectory tracking control method for an underactuated stratospheric airship is presented in this paper. Firstly, the TLC theory is described sketchily, and the dynamic model of the stratospheric airship is introduced with kinematics and dynamics equations. Then, the trajectory tracking control strategy is deduced in detail. The designed control system possesses a cascaded structure which consists of desired attitude calculation, position control loop and attitude control loop. Two sub-loops are designed for the position and attitude control loops, respectively, including the kinematics control loop and dynamics control loop. Stability analysis shows that the controlled closed-loop system is exponentially stable. Finally, simulation results for the stratospheric airship to track typical trajectories are illustrated to verify effectiveness of the proposed approach.

  4. The existence of trajectories joining critical points

    International Nuclear Information System (INIS)

    Yu Shuxiang.

    1985-01-01

    In this paper, using the notion of an isolating block and the concept of canonical regions, three existence criteria of trajectories connecting a pair of critical points of planar differential equations are given. (author)

  5. Trajectory phases of a quantum dot model

    International Nuclear Information System (INIS)

    Genway, Sam; Hickey, James M; Garrahan, Juan P; Armour, Andrew D

    2014-01-01

    We present a thermodynamic formalism to study the trajectories of charge transport through a quantum dot coupled to two leads in the resonant-level model. We show that a close analogue of equilibrium phase transitions exists for the statistics of transferred charge; by tuning an appropriate ‘counting field’, crossovers to different trajectory phases are possible. Our description reveals a mapping between the statistics of a given device and current measurements over a range of devices with different dot–lead coupling strengths. Furthermore insight into features of the trajectory phases are found by studying the occupation of the dot conditioned on the transported charge between the leads; this is calculated from first principles using a trajectory biased two-point projective measurement scheme. (paper)

  6. Trajectory averaging for stochastic approximation MCMC algorithms

    KAUST Repository

    Liang, Faming

    2010-01-01

    to the stochastic approximation Monte Carlo algorithm [Liang, Liu and Carroll J. Amer. Statist. Assoc. 102 (2007) 305-320]. The application of the trajectory averaging estimator to other stochastic approximationMCMC algorithms, for example, a stochastic

  7. Quantum dynamics modeled by interacting trajectories

    Science.gov (United States)

    Cruz-Rodríguez, L.; Uranga-Piña, L.; Martínez-Mesa, A.; Meier, C.

    2018-03-01

    We present quantum dynamical simulations based on the propagation of interacting trajectories where the effect of the quantum potential is mimicked by effective pseudo-particle interactions. The method is applied to several quantum systems, both for bound and scattering problems. For the bound systems, the quantum ground state density and zero point energy are shown to be perfectly obtained by the interacting trajectories. In the case of time-dependent quantum scattering, the Eckart barrier and uphill ramp are considered, with transmission coefficients in very good agreement with standard quantum calculations. Finally, we show that via wave function synthesis along the trajectories, correlation functions and energy spectra can be obtained based on the dynamics of interacting trajectories.

  8. Action Recognition Using Discriminative Structured Trajectory Groups

    KAUST Repository

    Atmosukarto, Indriyati

    2015-01-06

    In this paper, we develop a novel framework for action recognition in videos. The framework is based on automatically learning the discriminative trajectory groups that are relevant to an action. Different from previous approaches, our method does not require complex computation for graph matching or complex latent models to localize the parts. We model a video as a structured bag of trajectory groups with latent class variables. We model action recognition problem in a weakly supervised setting and learn discriminative trajectory groups by employing multiple instance learning (MIL) based Support Vector Machine (SVM) using pre-computed kernels. The kernels depend on the spatio-temporal relationship between the extracted trajectory groups and their associated features. We demonstrate both quantitatively and qualitatively that the classification performance of our proposed method is superior to baselines and several state-of-the-art approaches on three challenging standard benchmark datasets.

  9. Study of particle swarm optimization particle trajectories

    CSIR Research Space (South Africa)

    Van den Bergh, F

    2006-01-01

    Full Text Available . These theoretical studies concentrate mainly on simplified PSO systems. This paper overviews current theoretical studies, and extend these studies to investigate particle trajectories for general swarms to include the influence of the inertia term. The paper also...

  10. DIRECTIONAL WELL TRAJECTORY DESIGN: THE THEORITICAL ...

    African Journals Online (AJOL)

    user

    2016-10-04

    Oct 4, 2016 ... record presentation of a desired complex directional well trajectory, also from which the overall angle change. (dogleg) is observed not to ... example; 23oNE means 23 degrees East from North, .... Azimuth Angles Selection.

  11. Trajectory similarity join in spatial networks

    KAUST Repository

    Shang, Shuo; Chen, Lisi; Wei, Zhewei; Jensen, Christian S.; Zheng, Kai; Kalnis, Panos

    2017-01-01

    With these applications in mind, we provide a purposeful definition of similarity. To enable efficient TS-Join processing on large sets of trajectories, we develop search space pruning techniques and take into account the parallel processing capabilities of modern processors. Specifically, we present a two-phase divide-and-conquer algorithm. For each trajectory, the algorithm first finds similar trajectories. Then it merges the results to achieve a final result. The algorithm exploits an upper bound on the spatiotemporal similarity and a heuristic scheduling strategy for search space pruning. The algorithm's per-trajectory searches are independent of each other and can be performed in parallel, and the merging has constant cost. An empirical study with real data offers insight in the performance of the algorithm and demonstrates that is capable of outperforming a well-designed baseline algorithm by an order of magnitude.

  12. Trajectories of childhood weight gain: the relative importance of local environment versus individual social and early life factors.

    Directory of Open Access Journals (Sweden)

    Megan A Carter

    Full Text Available To determine the association between local environmental factors with child weight status in a longitudinal study, using a semi-parametric, group-based method, while also considering social and early life factors.Standardized, directly measured BMI from 4-10 y of age, and group-based trajectory modeling (PROC TRAJ were used to estimate developmental trajectories of weight change in a Québec birth cohort (n = 1,566. Associations between the weight trajectories and living location, social cohesion, disorder, and material and social deprivation were estimated after controlling for social and early life factors.FOUR WEIGHT TRAJECTORY GROUPS WERE ESTIMATED: low-increasing (9.7%; low-medium, accelerating (36.2%; medium-high, increasing (43.0%; and high-stable (11.1%. In the low-increasing and medium-high trajectory groups, living in a semi-urban area was inversely related to weight, while living in a rural area was positively related to weight in the high-stable group. Disorder was inversely related to weight in the low-increasing group only. Other important risk factors for high-stable weight included obesity status of the mother, smoking during pregnancy, and overeating behaviors.In this study, associations between local environment factors and weight differed by trajectory group. Early life factors appear to play a more consistent role in weight status. Further work is needed to determine the influence of place on child weight.

  13. Borderline personality disorder and the emerging field of developmental neuroscience.

    Science.gov (United States)

    Crowell, Sheila E; Kaufman, Erin A

    2016-10-01

    Over the past 2 decades there has been a dramatic shift in understanding of personality disorders, such as borderline personality disorder (BPD). What was historically viewed as an entrenched pattern of antagonistic, interpersonally dependent, and uncorrectable conduct is now seen as the outcome of complex-yet modifiable-developmental processes. The borderline label, which once inspired such harsh opprobrium in clinical communities that early diagnosis was considered taboo, is now increasingly applied to adolescents who are receiving effective treatment and desisting from a borderline trajectory. Research examining the developmental origins and early manifestations of BPD is increasing rapidly, making it an appropriate time to take stock of current developmental research and articulate an agenda for the future. We identify 4 challenges that continue to impede innovative research on borderline personality development: (a) inadequate attention to continuity and discontinuity across development, (b) medical and diagnostic systems that localize personality pathology within the individual, (c) the lingering belief that biological research is antithetical to contextual/interpersonal understandings of psychopathology (and vice versa), and (d) reluctance to reach across disciplinary and developmental boundaries to identify creative paradigms and foster innovative discovery. In order to overcome these challenges, we propose an approach to future research on adolescent borderline pathology that integrates developmental psychopathology, social and affective neuroscience, and personality theory perspectives. This intersection-the developmental neuroscience of personality pathology-offers theoretical and methodological advantages over disciplinary isolation and is fertile ground for generating novel hypotheses on the development and prevention of BPD. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  14. Kinematic evaluation of virtual walking trajectories.

    Science.gov (United States)

    Cirio, Gabriel; Olivier, Anne-Hélène; Marchal, Maud; Pettré, Julien

    2013-04-01

    Virtual walking, a fundamental task in Virtual Reality (VR), is greatly influenced by the locomotion interface being used, by the specificities of input and output devices, and by the way the virtual environment is represented. No matter how virtual walking is controlled, the generation of realistic virtual trajectories is absolutely required for some applications, especially those dedicated to the study of walking behaviors in VR, navigation through virtual places for architecture, rehabilitation and training. Previous studies focused on evaluating the realism of locomotion trajectories have mostly considered the result of the locomotion task (efficiency, accuracy) and its subjective perception (presence, cybersickness). Few focused on the locomotion trajectory itself, but in situation of geometrically constrained task. In this paper, we study the realism of unconstrained trajectories produced during virtual walking by addressing the following question: did the user reach his destination by virtually walking along a trajectory he would have followed in similar real conditions? To this end, we propose a comprehensive evaluation framework consisting on a set of trajectographical criteria and a locomotion model to generate reference trajectories. We consider a simple locomotion task where users walk between two oriented points in space. The travel path is analyzed both geometrically and temporally in comparison to simulated reference trajectories. In addition, we demonstrate the framework over a user study which considered an initial set of common and frequent virtual walking conditions, namely different input devices, output display devices, control laws, and visualization modalities. The study provides insight into the relative contributions of each condition to the overall realism of the resulting virtual trajectories.

  15. User Oriented Trajectory Search for Trip Recommendation

    KAUST Repository

    Ding, Ruogu

    2012-07-08

    Trajectory sharing and searching have received significant attention in recent years. In this thesis, we propose and investigate the methods to find and recommend the best trajectory to the traveler, and mainly focus on a novel technique named User Oriented Trajectory Search (UOTS) query processing. In contrast to conventional trajectory search by locations (spatial domain only), we consider both spatial and textual domains in the new UOTS query. Given a trajectory data set, the query input contains a set of intended places given by the traveler and a set of textual attributes describing the traveler’s preference. If a trajectory is connecting/close to the specified query locations, and the textual attributes of the trajectory are similar to the traveler’s preference, it will be recommended to the traveler. This type of queries can enable many popular applications such as trip planning and recommendation. There are two challenges in UOTS query processing, (i) how to constrain the searching range in two domains and (ii) how to schedule multiple query sources effectively. To overcome the challenges and answer the UOTS query efficiently, a novel collaborative searching approach is developed. Conceptually, the UOTS query processing is conducted in the spatial and textual domains alternately. A pair of upper and lower bounds are devised to constrain the searching range in two domains. In the meantime, a heuristic searching strategy based on priority ranking is adopted for scheduling the multiple query sources, which can further reduce the searching range and enhance the query efficiency notably. Furthermore, the devised collaborative searching approach can be extended to situations where the query locations are ordered. Extensive experiments are conducted on both real and synthetic trajectory data in road networks. Our approach is verified to be effective in reducing both CPU time and disk I/O time.

  16. Mobility Modelling through Trajectory Decomposition and Prediction

    OpenAIRE

    Faghihi, Farbod

    2017-01-01

    The ubiquity of mobile devices with positioning sensors make it possible to derive user's location at any time. However, constantly sensing the position in order to track the user's movement is not feasible, either due to the unavailability of sensors, or computational and storage burdens. In this thesis, we present and evaluate a novel approach for efficiently tracking user's movement trajectories using decomposition and prediction of trajectories. We facilitate tracking by taking advantage ...

  17. Trajectory Stability in the Traveling Salesman Problem

    Directory of Open Access Journals (Sweden)

    Sergio Sánchez

    2018-01-01

    Full Text Available Two generalizations of the traveling salesman problem in which sites change their position in time are presented. The way the rank of different trajectory lengths changes in time is studied using the rank diversity. We analyze the statistical properties of rank distributions and rank dynamics and give evidence that the shortest and longest trajectories are more predictable and robust to change, that is, more stable.

  18. Towards Developmental Connectomics of the Human Brain

    Directory of Open Access Journals (Sweden)

    Miao eCao

    2016-03-01

    Full Text Available Imaging connectomics based on graph theory has become an effective and unique methodological framework for studying structural and functional connectivity patterns of the developing brain. Normal brain development is characterized by continuous and significant network evolution throughout infancy, childhood and adolescence, following specific maturational patterns. Disruption of these normal changes is associated with neuropsychiatric developmental disorders, such as autism spectrum disorders or attention-deficit hyperactivity disorder. In this review, we focused on the recent progresses regarding typical and atypical development of human brain networks from birth to early adulthood, using a connectomic approach. Specifically, by the time of birth, structural networks already exhibit adult-like organization, with global efficient small-world and modular structures, as well as hub regions and rich-clubs acting as communication backbones. During development, the structure networks are fine-tuned, with increased global integration and robustness and decreased local segregation, as well as the strengthening of the hubs. In parallel, functional networks undergo more dramatic changes during maturation, with both increased integration and segregation during development, as brain hubs shift from primary regions to high order functioning regions, and the organization of modules transitions from a local anatomical emphasis to a more distributed architecture. These findings suggest that structural networks develop earlier than functional networks; meanwhile functional networks demonstrate more dramatic maturational changes with the evolution of structural networks serving as the anatomical backbone. In this review, we also highlighted topologically disorganized characteristics in structural and functional brain networks in several major developmental neuropsychiatric disorders (e.g., autism spectrum disorders, attention-deficit hyperactivity disorder and

  19. Toward Developmental Connectomics of the Human Brain.

    Science.gov (United States)

    Cao, Miao; Huang, Hao; Peng, Yun; Dong, Qi; He, Yong

    2016-01-01

    Imaging connectomics based on graph theory has become an effective and unique methodological framework for studying structural and functional connectivity patterns of the developing brain. Normal brain development is characterized by continuous and significant network evolution throughout infancy, childhood, and adolescence, following specific maturational patterns. Disruption of these normal changes is associated with neuropsychiatric developmental disorders, such as autism spectrum disorders or attention-deficit hyperactivity disorder. In this review, we focused on the recent progresses regarding typical and atypical development of human brain networks from birth to early adulthood, using a connectomic approach. Specifically, by the time of birth, structural networks already exhibit adult-like organization, with global efficient small-world and modular structures, as well as hub regions and rich-clubs acting as communication backbones. During development, the structure networks are fine-tuned, with increased global integration and robustness and decreased local segregation, as well as the strengthening of the hubs. In parallel, functional networks undergo more dramatic changes during maturation, with both increased integration and segregation during development, as brain hubs shift from primary regions to high order functioning regions, and the organization of modules transitions from a local anatomical emphasis to a more distributed architecture. These findings suggest that structural networks develop earlier than functional networks; meanwhile functional networks demonstrate more dramatic maturational changes with the evolution of structural networks serving as the anatomical backbone. In this review, we also highlighted topologically disorganized characteristics in structural and functional brain networks in several major developmental neuropsychiatric disorders (e.g., autism spectrum disorders, attention-deficit hyperactivity disorder and developmental

  20. Toward Developmental Connectomics of the Human Brain

    Science.gov (United States)

    Cao, Miao; Huang, Hao; Peng, Yun; Dong, Qi; He, Yong

    2016-01-01

    Imaging connectomics based on graph theory has become an effective and unique methodological framework for studying structural and functional connectivity patterns of the developing brain. Normal brain development is characterized by continuous and significant network evolution throughout infancy, childhood, and adolescence, following specific maturational patterns. Disruption of these normal changes is associated with neuropsychiatric developmental disorders, such as autism spectrum disorders or attention-deficit hyperactivity disorder. In this review, we focused on the recent progresses regarding typical and atypical development of human brain networks from birth to early adulthood, using a connectomic approach. Specifically, by the time of birth, structural networks already exhibit adult-like organization, with global efficient small-world and modular structures, as well as hub regions and rich-clubs acting as communication backbones. During development, the structure networks are fine-tuned, with increased global integration and robustness and decreased local segregation, as well as the strengthening of the hubs. In parallel, functional networks undergo more dramatic changes during maturation, with both increased integration and segregation during development, as brain hubs shift from primary regions to high order functioning regions, and the organization of modules transitions from a local anatomical emphasis to a more distributed architecture. These findings suggest that structural networks develop earlier than functional networks; meanwhile functional networks demonstrate more dramatic maturational changes with the evolution of structural networks serving as the anatomical backbone. In this review, we also highlighted topologically disorganized characteristics in structural and functional brain networks in several major developmental neuropsychiatric disorders (e.g., autism spectrum disorders, attention-deficit hyperactivity disorder and developmental

  1. Online Detection of Anomalous Sub-trajectories: A Sliding Window Approach Based on Conformal Anomaly Detection and Local Outlier Factor

    OpenAIRE

    Laxhammar , Rikard; Falkman , Göran

    2012-01-01

    Part 4: First Conformal Prediction and Its Applications Workshop (COPA 2012); International audience; Automated detection of anomalous trajectories is an important problem in the surveillance domain. Various algorithms based on learning of normal trajectory patterns have been proposed for this problem. Yet, these algorithms suffer from one or more of the following limitations: First, they are essentially designed for offline anomaly detection in databases. Second, they are insensitive to loca...

  2. Developmental programming of auditory learning

    Directory of Open Access Journals (Sweden)

    Melania Puddu

    2012-10-01

    Full Text Available The basic structures involved in the development of auditory function and consequently in language acquisition are directed by genetic code, but the expression of individual genes may be altered by exposure to environmental factors, which if favorable, orient it in the proper direction, leading its development towards normality, if unfavorable, they deviate it from its physiological course. Early sensorial experience during the foetal period (i.e. intrauterine noise floor, sounds coming from the outside and attenuated by the uterine filter, particularly mother’s voice and modifications induced by it at the cochlear level represent the first example of programming in one of the earliest critical periods in development of the auditory system. This review will examine the factors that influence the developmental programming of auditory learning from the womb to the infancy. In particular it focuses on the following points: the prenatal auditory experience and the plastic phenomena presumably induced by it in the auditory system from the basilar membrane to the cortex;the involvement of these phenomena on language acquisition and on the perception of language communicative intention after birth;the consequences of auditory deprivation in critical periods of auditory development (i.e. premature interruption of foetal life.

  3. Optimizing interplanetary trajectories with deep space maneuvers

    Science.gov (United States)

    Navagh, John

    1993-09-01

    Analysis of interplanetary trajectories is a crucial area for both manned and unmanned missions of the Space Exploration Initiative. A deep space maneuver (DSM) can improve a trajectory in much the same way as a planetary swingby. However, instead of using a gravitational field to alter the trajectory, the on-board propulsion system of the spacecraft is used when the vehicle is not near a planet. The purpose is to develop an algorithm to determine where and when to use deep space maneuvers to reduce the cost of a trajectory. The approach taken to solve this problem uses primer vector theory in combination with a non-linear optimizing program to minimize Delta(V). A set of necessary conditions on the primer vector is shown to indicate whether a deep space maneuver will be beneficial. Deep space maneuvers are applied to a round trip mission to Mars to determine their effect on the launch opportunities. Other studies which were performed include cycler trajectories and Mars mission abort scenarios. It was found that the software developed was able to locate quickly DSM's which lower the total Delta(V) on these trajectories.

  4. Searching Trajectories by Regions of Interest

    KAUST Repository

    Shang, Shuo

    2017-03-22

    With the increasing availability of moving-object tracking data, trajectory search is increasingly important. We propose and investigate a novel query type named trajectory search by regions of interest (TSR query). Given an argument set of trajectories, a TSR query takes a set of regions of interest as a parameter and returns the trajectory in the argument set with the highest spatial-density correlation to the query regions. This type of query is useful in many popular applications such as trip planning and recommendation, and location based services in general. TSR query processing faces three challenges: how to model the spatial-density correlation between query regions and data trajectories, how to effectively prune the search space, and how to effectively schedule multiple so-called query sources. To tackle these challenges, a series of new metrics are defined to model spatial-density correlations. An efficient trajectory search algorithm is developed that exploits upper and lower bounds to prune the search space and that adopts a query-source selection strategy, as well as integrates a heuristic search strategy based on priority ranking to schedule multiple query sources. The performance of TSR query processing is studied in extensive experiments based on real and synthetic spatial data.

  5. Searching Trajectories by Regions of Interest

    KAUST Repository

    Shang, Shuo; chen, Lisi; Jensen, Christian S.; Wen, Ji-Rong; Kalnis, Panos

    2017-01-01

    With the increasing availability of moving-object tracking data, trajectory search is increasingly important. We propose and investigate a novel query type named trajectory search by regions of interest (TSR query). Given an argument set of trajectories, a TSR query takes a set of regions of interest as a parameter and returns the trajectory in the argument set with the highest spatial-density correlation to the query regions. This type of query is useful in many popular applications such as trip planning and recommendation, and location based services in general. TSR query processing faces three challenges: how to model the spatial-density correlation between query regions and data trajectories, how to effectively prune the search space, and how to effectively schedule multiple so-called query sources. To tackle these challenges, a series of new metrics are defined to model spatial-density correlations. An efficient trajectory search algorithm is developed that exploits upper and lower bounds to prune the search space and that adopts a query-source selection strategy, as well as integrates a heuristic search strategy based on priority ranking to schedule multiple query sources. The performance of TSR query processing is studied in extensive experiments based on real and synthetic spatial data.

  6. UAV Trajectory Modeling Using Neural Networks

    Science.gov (United States)

    Xue, Min

    2017-01-01

    Massive small unmanned aerial vehicles are envisioned to operate in the near future. While there are lots of research problems need to be addressed before dense operations can happen, trajectory modeling remains as one of the keys to understand and develop policies, regulations, and requirements for safe and efficient unmanned aerial vehicle operations. The fidelity requirement of a small unmanned vehicle trajectory model is high because these vehicles are sensitive to winds due to their small size and low operational altitude. Both vehicle control systems and dynamic models are needed for trajectory modeling, which makes the modeling a great challenge, especially considering the fact that manufactures are not willing to share their control systems. This work proposed to use a neural network approach for modelling small unmanned vehicle's trajectory without knowing its control system and bypassing exhaustive efforts for aerodynamic parameter identification. As a proof of concept, instead of collecting data from flight tests, this work used the trajectory data generated by a mathematical vehicle model for training and testing the neural network. The results showed great promise because the trained neural network can predict 4D trajectories accurately, and prediction errors were less than 2:0 meters in both temporal and spatial dimensions.

  7. Ethnic Variations of Trajectories in Suicide Ideation and Attempt: From Middle School to High School.

    Science.gov (United States)

    Kim, Jahun; Pike, Kenneth; McCauley, Elizabeth; Vander Stoep, Ann

    2018-02-14

    The purpose of this study was to compare patterns of suicide ideation and suicide attempt in three ethnic groups. We analyzed data from 463 students with ethnic backgrounds of African American (AA), Asian American (ASA), and European American (EA) for 6 years. The best fit model was a three-trajectory class model for all groups. The majority of adolescents belonged in the nonideators trajectory. The high level of ideation was found in the high ideators (4%), high-fluctuating ideators (8%), and high-decreasing ideators (4%) trajectory in AA, ASA, and EA, respectively. In the AA group, being a member of ideators was not a significant predictor of suicide attempt. In the ASA group, being a member of high-fluctuating ideators was a significant predictor. In the EA group, being a member of both ideators predicted suicide attempt. The timing of onset, patterns of change, and peak time in the ideators trajectories in the three ethnic groups were markedly different. The high level of attempts found in the ASA-AA group was not explained by having suicide ideation. Findings suggest the need for in-depth examination of suicide behaviors across ethnic groups and culturally adapted preventive efforts with distinct developmental timing for adolescents from different ethnic backgrounds. © 2018 The American Association of Suicidology.

  8. Mental health trajectories from adolescence to adulthood: Language disorder and other childhood and adolescent risk factors.

    Science.gov (United States)

    Bao, Lin; Brownlie, E B; Beitchman, Joseph H

    2016-05-01

    Longitudinal research on mental health development beyond adolescence among nonclinical populations is lacking. This study reports on psychiatric disorder trajectories from late adolescence to young adulthood in relation to childhood and adolescent risk factors. Participants were recruited for a prospective longitudinal study tracing a community sample of 5-year-old children with communication disorders and a matched control cohort to age 31. Psychiatric disorders were measured at ages 19, 25, and 31. Known predictors of psychopathology and two school-related factors specifically associated with language disorder (LD) were measured by self-reports and semistructured interviews. The LD cohort was uniquely characterized by a significantly decreasing disorder trajectory in early adulthood. Special education was associated with differential disorder trajectories between LD and control cohorts, whereas maltreatment history, specific learning disorder, family structure, and maternal psychological distress were associated with consistent trajectories between cohorts. From late adolescence to young adulthood, childhood LD was characterized by a developmentally limited course of psychiatric disorder; maltreatment was consistently characterized by an elevated risk of psychiatric disorder regardless of LD history, whereas special education was associated with significantly decreasing risk of psychiatric disorder only in the presence of LD.

  9. Parenting Styles and Body Mass Index Trajectories From Adolescence to Adulthood

    Science.gov (United States)

    Fuemmeler, Bernard F.; Yang, Chongming; Costanzo, Phil; Hoyle, Rick H.; Ph.D.; Siegler, Ilene C.; Williams, Redford B.; Østbye, Truls

    2013-01-01

    Objective Parenting styles such as authoritarian, disengaged, or permissive are thought to be associated with greater adolescent obesity risk than an authoritative style. This study assessed the relationship between parenting styles and changes in body mass index (BMI) from adolescence to young adulthood. Methods The study included self-reported data from adolescents in the National Longitudinal Study of Adolescent Health. Factor mixture modeling, a data-driven approach, was used to classify participants into parenting style groups based on measures of acceptance and control. Latent growth modeling (LGM) identified patterns of developmental changes in BMI. After a number of potential cofounders were controlled for, parenting style variables were entered as predictors of BMI trajectories. Analyses were also conducted for males and females of three racial/ethnic groups (Hispanic, black, white) to assess whether parenting styles were differentially associated with BMI trajectories in these 6 groups. Results Parenting styles were classified into 4 groups: authoritarian, disengaged, permissive, and balanced. Compared with the balanced parenting style, authoritarian and disengaged parenting styles were associated with a less steep average BMI increase (linear slope) over time, but also less leveling off (quadratic) of BMI over time. Differences in BMI trajectories were observed for various genders and races, but the differences did not reach statistical significance. Conclusions Adolescents who reported having parents with authoritarian or disengaged parenting styles had greater increases in BMI as they transitioned to young adulthood despite having a lower BMI trajectory through adolescence. PMID:22545979

  10. Parenting styles and body mass index trajectories from adolescence to adulthood.

    Science.gov (United States)

    Fuemmeler, Bernard F; Yang, Chongming; Costanzo, Phil; Hoyle, Rick H; Siegler, Ilene C; Williams, Redford B; Ostbye, Truls

    2012-07-01

    Parenting styles such as authoritarian, disengaged, or permissive are thought to be associated with greater adolescent obesity risk than an authoritative style. This study assessed the relationship between parenting styles and changes in body mass index (BMI) from adolescence to young adulthood. The study included self-reported data from adolescents in the National Longitudinal Study of Adolescent Health. Factor mixture modeling, a data-driven approach, was used to classify participants into parenting style groups based on measures of acceptance and control. Latent growth modeling (LGM) identified patterns of developmental changes in BMI. After a number of potential confounders were controlled for, parenting style variables were entered as predictors of BMI trajectories. Analyses were also conducted for male and female individuals of 3 racial-ethnic groups (Hispanic, black, white) to assess whether parenting styles were differentially associated with BMI trajectories in these 6 groups. Parenting styles were classified into 4 groups: authoritarian, disengaged, permissive, and balanced. Compared with the balanced parenting style, authoritarian and disengaged parenting styles were associated with a less steep average BMI increase (linear slope) over time, but also less leveling off (quadratic) of BMI over time. Differences in BMI trajectories were observed for various genders and races, but the differences did not reach statistical significance. Adolescents who reported having parents with authoritarian or disengaged parenting styles had greater increases in BMI as they transitioned to young adulthood despite having a lower BMI trajectory through adolescence.

  11. Ethnic differences in associations among popularity, likability, and trajectories of adolescents' alcohol use and frequency.

    Science.gov (United States)

    Choukas-Bradley, Sophia; Giletta, Matteo; Neblett, Enrique W; Prinstein, Mitchell J

    2015-01-01

    Two-part latent growth models examined associations between two forms of peer status (popularity, likability) and adolescents' alcohol use trajectories throughout high school; ethnicity was examined as a moderator. Ninth-grade low-income adolescents (N = 364; Mage = 15.08; 52.5% Caucasian; 25.8% African American; 21.7% Latino) completed sociometric nominations of peer status and aggression at baseline, and reported their alcohol use every 6 months. After controlling for gender, aggression, ethnicity, and socioeconomic status, popularity-but not likability-prospectively predicted alcohol use trajectories. However, these effects were moderated by ethnicity, suggesting popularity as a risk factor for alcohol use probability and frequency among Caucasian and Latino, but not African American adolescents. Results suggest that developmental correlates of peer status should be considered within cultural context. © 2015 The Authors. Child Development © 2015 Society for Research in Child Development, Inc.

  12. The neonatal methylome as a gatekeeper in the trajectory to childhood asthma.

    Science.gov (United States)

    DeVries, Avery; Vercelli, Donata

    2017-04-01

    Asthma is a heterogeneous group of conditions that typically begin in early life and result in recurrent, reversible bronchial obstruction. The role played by epigenetic mechanisms in the pathogenesis of childhood asthma is understood only in part. Here we discuss asthma epigenetics within a developmental perspective based on our recent demonstration that the epigenetic trajectory to childhood asthma begins at birth. We next discuss how this trajectory may be affected by prenatal environmental exposures. Finally, we examine in vitro studies that model the impact of asthma-associated exposures on the epigenome. All of these studies specifically surveyed human DNA methylation and involved a genome-wide component. In combination, their results broaden our understanding of asthma pathogenesis and the role the methylome plays in this process.

  13. Perinatal Programming of Childhood Asthma: Early Fetal Size, Growth Trajectory during Infancy, and Childhood Asthma Outcomes

    Directory of Open Access Journals (Sweden)

    Steve Turner

    2012-01-01

    Full Text Available The “fetal origins hypothesis” or concept of “developmental programming” suggests that faltering fetal growth and subsequent catch-up growth are implicated in the aetiology of cardiovascular disease. Associations between reduced birth weight, rapid postnatal weight gain, and asthma suggest that there are fetal origins to respiratory disease. The present paper first summarises the literature relating birth weight and post natal growth trajectories to asthma outcomes. Second, issues regarding the interpretation of antenatal fetal ultrasound measurements are discussed. Finally, recent reports linking antenatal measurement and growth trajectory to early childhood asthma outcomes are discussed. Understanding the nature and timing of factors which influence antenatal growth may give important insight into the antecedents of early-onset asthma with implications for interventions.

  14. Perinatal programming of childhood asthma: early fetal size, growth trajectory during infancy, and childhood asthma outcomes.

    Science.gov (United States)

    Turner, Steve

    2012-01-01

    The "fetal origins hypothesis" or concept of "developmental programming" suggests that faltering fetal growth and subsequent catch-up growth are implicated in the aetiology of cardiovascular disease. Associations between reduced birth weight, rapid postnatal weight gain, and asthma suggest that there are fetal origins to respiratory disease. The present paper first summarises the literature relating birth weight and post natal growth trajectories to asthma outcomes. Second, issues regarding the interpretation of antenatal fetal ultrasound measurements are discussed. Finally, recent reports linking antenatal measurement and growth trajectory to early childhood asthma outcomes are discussed. Understanding the nature and timing of factors which influence antenatal growth may give important insight into the antecedents of early-onset asthma with implications for interventions.

  15. Topographic processing in developmental prosopagnosia

    DEFF Research Database (Denmark)

    Klargaard, Solja K.; Starrfelt, Randi; Petersen, Anders

    2016-01-01

    deficit in visual processing or visual short-term memory. Interestingly, a classical dissociation could be demonstrated between impaired face memory and preserved topographic memory in two developmental prosopagnosics. We conclude that impairments in topographic memory tend to co-occur with developmental......Anecdotal evidence suggests a relation between impaired spatial (navigational) processing and developmental prosopagnosia. To address this formally, we tested two aspects of topographic processing – that is, perception and memory of mountain landscapes shown from different viewpoints. Participants...

  16. DEVELOPMENTAL TAXONOMY OF CONDUCT DISORDER

    OpenAIRE

    Jelena Kostić; Milkica Nešić; Jasminka Marković; Miodrag Stanković

    2015-01-01

    Conduct disorder is a heterogeneous disorder in terms of etiology, course and prognosis, and currently, there is no singular model that would describe the development of the disorder. The results of empirical research on males confirm this heterogeneity, as they point out to two possible developmental pathways: childhood-onset and adolescentonset type. This paper presents the basic elements of developmental taxonomic theory which argues that there are two different developmental pathways to c...

  17. Physical Fitness in Children with Developmental Coordination Disorder

    Science.gov (United States)

    Schott, Nadja; Alof, Verena; Hultsch, Daniela; Meermann, Dagmar

    2007-01-01

    The protective effects of physical activity and fitness on cardiovascular health have clearly been shown among normally developed children. However, data are currently lacking pertaining to children with developmental coordination disorder (DCD). The purpose of this study was to examine differences in fitness measures, body composition, and…

  18. (Dys)functional Guilt and Shame in Developmental Perspective.

    Science.gov (United States)

    Ferguson, T.; And Others

    Sociologists and psychologists have shown increasing interest in moral emotions such as pride, shame, and guilt, including their developmental role. While these emotions have an important part in normal development, the chronically shame-prone person has feelings of worthlessness, incompetence, and helplessness; a guilt-prone person dwells on…

  19. Is Season of Birth Related to Developmental Dyslexia?

    Science.gov (United States)

    Donfrancesco, Renato; Iozzino, Roberto; Caruso, Barbara; Ferrante, Laura; Mugnaini, Daniele; Talamo, Alessandra; Miano, Silvia; Dimitri, Andrea; Masi, Gabriele

    2010-01-01

    Different moderators/mediators of risk are involved in developmental dyslexia (DD), but data are inconsistent. We explored the prevalence of season of birth and its association with gender and age of school entry in an Italian sample of dyslexic children compared to an Italian normal control group. The clinical sample included 498 children (345…

  20. Developmental Language Disorders--A Follow-Up in Later Adult Life. Cognitive, Language and Psychosocial Outcomes

    Science.gov (United States)

    Clegg, J.; Hollis, C.; Mawhood, L.; Rutter, M.

    2005-01-01

    Background: Little is known on the adult outcome and longitudinal trajectory of childhood developmental language disorders (DLD) and on the prognostic predictors. Method: Seventeen men with a severe receptive DLD in childhood, reassessed in middle childhood and early adult life, were studied again in their mid-thirties with tests of intelligence…

  1. Developmental plasticity: Friend or foe?

    Science.gov (United States)

    Michels, Karin B

    2017-01-01

    Developmental plasticity - the concept that adaptation to changing and unfavorable environmental conditions are possible but may come at the price of compromised health potentials - has evolutionary grounding as it facilitates survival but dissents with fundamental evolutionary principles in that it may advance the lesser fit. It is an important cornerstone of the Developmental Origins of Health and Disease (DOHaD). Unlike evolutionary adaptation developmental plasticity may be short-lived and restricted to one or few generations and inheritance is uncertain. Potential mechanisms include epigenetic modifications adopted in utero which may not transmit to the next generation; future insights may allow adjustments of the outcomes of developmental plasticity.

  2. Qualitative methodology in developmental psychology

    DEFF Research Database (Denmark)

    Demuth, Carolin; Mey, Günter

    2015-01-01

    Qualitative methodology presently is gaining increasing recognition in developmental psychology. Although the founders of developmental psychology to a large extent already used qualitative procedures, the field was long dominated by a (post) positivistic quantitative paradigm. The increasing rec...... in qualitative research offers a promising avenue to advance the field in this direction.......Qualitative methodology presently is gaining increasing recognition in developmental psychology. Although the founders of developmental psychology to a large extent already used qualitative procedures, the field was long dominated by a (post) positivistic quantitative paradigm. The increasing...

  3. Building a developmental toxicity ontology.

    Science.gov (United States)

    Baker, Nancy; Boobis, Alan; Burgoon, Lyle; Carney, Edward; Currie, Richard; Fritsche, Ellen; Knudsen, Thomas; Laffont, Madeleine; Piersma, Aldert H; Poole, Alan; Schneider, Steffen; Daston, George

    2018-04-03

    As more information is generated about modes of action for developmental toxicity and more data are generated using high-throughput and high-content technologies, it is becoming necessary to organize that information. This report discussed the need for a systematic representation of knowledge about developmental toxicity (i.e., an ontology) and proposes a method to build one based on knowledge of developmental biology and mode of action/ adverse outcome pathways in developmental toxicity. This report is the result of a consensus working group developing a plan to create an ontology for developmental toxicity that spans multiple levels of biological organization. This report provide a description of some of the challenges in building a developmental toxicity ontology and outlines a proposed methodology to meet those challenges. As the ontology is built on currently available web-based resources, a review of these resources is provided. Case studies on one of the most well-understood morphogens and developmental toxicants, retinoic acid, are presented as examples of how such an ontology might be developed. This report outlines an approach to construct a developmental toxicity ontology. Such an ontology will facilitate computer-based prediction of substances likely to induce human developmental toxicity. © 2018 Wiley Periodicals, Inc.

  4. Trajectories of Ethnic-Racial Identity and Autonomy among Mexican-origin Adolescent Mothers in the U.S

    Science.gov (United States)

    Umaña-Taylor, Adriana J.; Updegraff, Kimberly A.; Jahromi, Laudan B.; Zeiders, Katharine H.

    2015-01-01

    This study examined trajectories of ethnic-racial identity (ERI) and autonomy development among Mexican-origin adolescent females in the U.S. (N = 181; Mage at Wave 1 = 16.80 years, SD = 1.00) as they transitioned through the first five years of parenthood. Trajectories of ERI and autonomy also were examined in relation to psychosocial functioning. Unconditional latent growth models indicated significant growth in autonomy, ERI resolution, and ERI affirmation from middle to late adolescence. Conditional latent growth models indicated that autonomy and ERI exploration growth trajectories were positively associated with psychosocial adjustment. Although adolescent mothers are experiencing transitions that are not normative during adolescence, they also engage in normative developmental processes, and their engagement in such processes is linked with better adjustment. PMID:26450526

  5. Personality development from adolescence to emerging adulthood: linking trajectories of ego development to the family context and identity formation.

    Science.gov (United States)

    Syed, Moin; Seiffge-Krenke, Inge

    2013-02-01

    This longitudinal study analyzed personality development using an individual approach by examining changes in ego development across the transition from adolescence to emerging adulthood. Specifically, the study mapped the heterogeniety in ego development growth trajectories and linked the different trajectories to the family context in adolescence and identity development in emerging adulthood. Participants were 98 families with a child who were followed from age 14 to age 24. Latent class growth analysis identified 4 distinct trajectories of growth in ego development of the children over the 10-year period. The results indicated that growth was more rapid during adolescence and tended to taper off in emerging adulthood. In addition, promotion of personal growth within the family and parents' ego development were particulary instrumental in children's ego developmental gains in adolescence. Finally, youth who demonstrated continued ego development into emerging adulthood also demonstrated heightened levels of identity exploration. (c) 2013 APA, all rights reserved.

  6. Developmental immunotoxicology of lead

    International Nuclear Information System (INIS)

    Dietert, Rodney R.; Lee, Ji-Eun; Hussain, Irshad; Piepenbrink, Michael

    2004-01-01

    The heavy metal, lead, is a known developmental immunotoxicant that has been shown to produce immune alterations in humans as well as other species. Unlike many compounds that exert adverse immune effects, lead exposure at low to moderate levels does not produce widespread loss of immune cells. In contrast, changes resulting from lead exposure are subtle at the immune cell population level but, nevertheless, can be functionally dramatic. A hallmark of lead-induced immunotoxicity is a pronounced shift in the balance in T helper cell function toward T helper 2 responses at the expense of T helper 1 functions. This bias alters the nature and range of immune responses that can be produced thereby influencing host susceptibility to various diseases. Immunotoxic responses to lead appear to differ across life stages not only quantitatively with regard to dose response, but also qualitatively in terms of the spectrum of immune alterations. Experimental studies in several lab animal species suggest the latter stages of gestation are a period of considerable sensitivity for lead-induced immunotoxicity. This review describes the basic characteristics of lead-induced immunotoxicity emphasizing experimental animal results. It also provides a framework for the consideration of toxicant exposure effects across life stages. The existence of and probable basis for developmental windows of immune hyper-susceptibility are presented. Finally, the potential for lead to serve as a perinatal risk factor for childhood asthma as well as other diseases is considered

  7. Asian and African Development Trajectories Revisiting Facts and Figures

    Directory of Open Access Journals (Sweden)

    Gilles Carbonnier

    2013-05-01

    Full Text Available In today’s dominant discourse, the development trajectory of many East Asian countries is pictured as a success, whereas that of many sub-Saharan African countries is considered a failure. The Asian success stories often refer to the developmental state model, which highlights the pivotal role played by Asian political elites in catalyzing economic growth and broad-based development. The model includes economic liberalization and outward-oriented policies, with targeted support to – and protection of – strategic sectors and infant industries.How far is this underlying assumption supported by empirical evidence? This working paper examines a wide range of economic, social, institutional and governance indicators for a sample of six sub-Saharan and five South East Asian countries. Contrary to our research hypothesis, we did not find any significant difference in the level of government involvement in the domestic economy between the countries of the two regions, nor in the quality of institutions and governance indicators, nor in the share of imports and exports in GDP.Even if there are important gaps between the two regions, for instance with regard to the demographic transition, the agricultural sector or tertiary education, the picture is much more nuanced than portrayed by the dominant discourse. Our review of economic and socio-political indicators tells a rather different story, but not the whole story. Nevertheless, the indicators fail to take into account all the historical, institutional and structural factors that matter a great deal for development. Hence our analysis should be complemented by detailed country case studies to uncover the specific dynamics underlying different development trajectories and outcomes.

  8. Developmental reading disorder

    Science.gov (United States)

    ... people with DRD have normal or above-average intelligence. DRD may appear with other problems. These can ... 2018, A.D.A.M., Inc. Duplication for commercial use must be authorized in writing by ADAM ...

  9. User oriented trajectory search for trip recommendation

    KAUST Repository

    Shang, Shuo

    2012-01-01

    Trajectory sharing and searching have received significant attentions in recent years. In this paper, we propose and investigate a novel problem called User Oriented Trajectory Search (UOTS) for trip recommendation. In contrast to conventional trajectory search by locations (spatial domain only), we consider both spatial and textual domains in the new UOTS query. Given a trajectory data set, the query input contains a set of intended places given by the traveler and a set of textual attributes describing the traveler\\'s preference. If a trajectory is connecting/close to the specified query locations, and the textual attributes of the trajectory are similar to the traveler\\'e preference, it will be recommended to the traveler for reference. This type of queries can bring significant benefits to travelers in many popular applications such as trip planning and recommendation. There are two challenges in the UOTS problem, (i) how to constrain the searching range in two domains and (ii) how to schedule multiple query sources effectively. To overcome the challenges and answer the UOTS query efficiently, a novel collaborative searching approach is developed. Conceptually, the UOTS query processing is conducted in the spatial and textual domains alternately. A pair of upper and lower bounds are devised to constrain the searching range in two domains. In the meantime, a heuristic searching strategy based on priority ranking is adopted for scheduling the multiple query sources, which can further reduce the searching range and enhance the query efficiency notably. Furthermore, the devised collaborative searching approach can be extended to situations where the query locations are ordered. The performance of the proposed UOTS query is verified by extensive experiments based on real and synthetic trajectory data in road networks. © 2012 ACM.

  10. Shadowing of physical trajectories in chaotic dynamics: Containment and refinement

    International Nuclear Information System (INIS)

    Grebogi, C.; Hammel, S.M.; Yorke, J.A.; Sauer, T.

    1990-01-01

    For a chaotic system, a noisy trajectory diverges rapidly from the true trajectory with the same initial condition. To understand in what sense the noisy trajectory reflects the true dynamics of the actual system, we developed a rigorous procedure to show that some true trajectories remain close to the noisy one for long times. The procedure involves a combination of containment, which establishes the existence of an uncountable number of true trajectories close to the noisy one, and refinement, which produces a less noisy trajectory. Our procedure is applied to noisy chaotic trajectories of the standard map and the driven pendulum

  11. I. DEVELOPMENTAL METHODOLOGY AS A CENTRAL SUBDISCIPLINE OF DEVELOPMENTAL SCIENCE.

    Science.gov (United States)

    Card, Noel A

    2017-06-01

    This first chapter introduces the main goals of the monograph and previews the remaining chapters. The goals of this monograph are to provide summaries of our current understanding of advanced developmental methodologies, provide information that can advance our understanding of human development, identify shortcomings in our understanding of developmental methodology, and serve as a flagpost for organizing developmental methodology as a subdiscipline within the broader field of developmental science. The remaining chapters in this monograph address issues in design (sampling and big data), longitudinal data analysis, and issues of replication and research accumulation. The final chapter describes the history of developmental methodology, considers how the previous chapters in this monograph fit within this subdiscipline, and offers recommendations for further advancement. © 2017 The Society for Research in Child Development, Inc.

  12. Constructivist developmental theory is needed in developmental neuroscience

    Science.gov (United States)

    Arsalidou, Marie; Pascual-Leone, Juan

    2016-12-01

    Neuroscience techniques provide an open window previously unavailable to the origin of thoughts and actions in children. Developmental cognitive neuroscience is booming, and knowledge from human brain mapping is finding its way into education and pediatric practice. Promises of application in developmental cognitive neuroscience rests however on better theory-guided data interpretation. Massive amounts of neuroimaging data from children are being processed, yet published studies often do not frame their work within developmental models—in detriment, we believe, to progress in this field. Here we describe some core challenges in interpreting the data from developmental cognitive neuroscience, and advocate the use of constructivist developmental theories of human cognition with a neuroscience interpretation.

  13. Household Food Insecurity and Children's Behaviour Problems: New Evidence from a Trajectories-Based Study

    Science.gov (United States)

    Huang, Jin; Vaughn, Michael G.

    2016-01-01

    This study examined the association between household food insecurity (insufficient access to adequate and nutritious food) and trajectories of externalising and internalising behaviour problems in children from kindergarten to fifth grade using longitudinal data from the Early Childhood Longitudinal Study—Kindergarten Cohort (ECLS-K), a nationally representative study in the USA. Household food insecurity was assessed using the eighteen-item standard food security scale, and children's behaviour problems were reported by teachers. Latent growth curve analysis was conducted on 7,348 children in the ECLS-K, separately for boys and girls. Following adjustment for an extensive array of confounding variables, results suggest that food insecurity generally was not associated with developmental change in children's behaviour problems. The impact of food insecurity on behaviour problems may be episodic or interact with certain developmental stages. PMID:27559210

  14. Attention trajectories, mechanisms and outcomes: at the interface between developing cognition and environment.

    Science.gov (United States)

    Scerif, Gaia

    2010-11-01

    Attentional processes play a crucial role in prioritizing information for further processing and they therefore sit at the interface between internal goals and the challenges presented by the environment. How does attentional control interact with the changing constraints imposed by the developing cognitive system? Emerging work in this area has employed a range of complementary techniques, from increasingly refined neurocognitive measures in typically developing individuals, to the investigation of risk or protective factors influencing attention trajectories in developmental disorders. A growing corpus of data suggests that, while attentional biases for specific input characteristics (e.g. suddenly appearing stimuli, emotional expressions) are in place from infancy, it is the interplay between these predispositions, genetic and environmental factors that drives attention development over time. With the advent of multidisciplinary approaches to the developmental cognitive neuroscience of attention, unravelling these complex dynamics from infancy and their outcome on learning is increasingly within reach. © 2010 Blackwell Publishing Ltd.

  15. Trajectory planning and trajectory tracking for a small-scale helicopter in autorotation

    NARCIS (Netherlands)

    Taamallah, Skander; Bombois, Xavier; Van den Hof, Paul M.J.

    2017-01-01

    The design of a high-performance guidance and control system for a small-scale helicopterUnmanned Aerial Vehicle (UAV), with an engine OFF flight condition (i.e. autorotation), is known to be a challenging task. It is the purpose of this paper to present a Trajectory Planning (TP) and Trajectory

  16. PRESS: A Novel Framework of Trajectory Compression in Road Networks

    OpenAIRE

    Song, Renchu; Sun, Weiwei; Zheng, Baihua; Zheng, Yu

    2014-01-01

    Location data becomes more and more important. In this paper, we focus on the trajectory data, and propose a new framework, namely PRESS (Paralleled Road-Network-Based Trajectory Compression), to effectively compress trajectory data under road network constraints. Different from existing work, PRESS proposes a novel representation for trajectories to separate the spatial representation of a trajectory from the temporal representation, and proposes a Hybrid Spatial Compression (HSC) algorithm ...

  17. Patterns of perceptual performance in Developmental Prosopagnosia

    DEFF Research Database (Denmark)

    Starrfelt, Randi; Petersen, Anders; Gerlach, Christian

    and Methods. 10 DPs and 20 matched controls participated in experimental tasks measuring recognition of faces, objects, letters, words, and scenes, as well as text reading, global-local processing (Navon’s paradigm), and visual attention / short-term memory. Performance was compared using both group...... and single case statistics. 3. Results. We find an intriguing pattern of preserved and impaired functions in DP: Letter and word recognition, text reading, and visual attention / short-term memory were normal. For geographical scenes, simultaneous matching was normal, while there was a group difference......1. Objective Developmental prosopagnosia (DP) is a life-long deficit in face recognition. The deficit is thought to be selective for faces, a hypothesis we tested by investigating patterns of associated and dissociated visuoperceptual and -attentional functions in a group of DPs. 2. Participants...

  18. Signatures of unstable semiclassical trajectories in tunneling

    International Nuclear Information System (INIS)

    Levkov, D G; Panin, A G; Sibiryakov, S M

    2009-01-01

    It was found recently that processes of multidimensional tunneling are generally described at high energies by unstable semiclassical trajectories. We study two observational signatures related to the instability of trajectories. First, we find an additional power-law dependence of the tunneling probability on the semiclassical parameter as compared to the standard case of potential tunneling. The second signature is a substantial widening of the probability distribution over final-state quantum numbers. These effects are studied using a modified semiclassical technique which incorporates stabilization of the tunneling trajectories. The technique is derived from first principles. We obtain expressions for the inclusive and exclusive tunneling probabilities in the case of unstable semiclassical trajectories. We also investigate the 'phase transition' between the cases of stable and unstable trajectories across certain 'critical' values of energy. Finally, we derive the relation between the semiclassical probabilities of tunneling from the low-lying and highly excited initial states. This puts on firm ground a conjecture made previously in the semiclassical description of collision-induced tunneling in field theory

  19. Trajectory attractors of equations of mathematical physics

    International Nuclear Information System (INIS)

    Vishik, Marko I; Chepyzhov, Vladimir V

    2011-01-01

    In this survey the method of trajectory dynamical systems and trajectory attractors is described, and is applied in the study of the limiting asymptotic behaviour of solutions of non-linear evolution equations. This method is especially useful in the study of dissipative equations of mathematical physics for which the corresponding Cauchy initial-value problem has a global (weak) solution with respect to the time but the uniqueness of this solution either has not been established or does not hold. An important example of such an equation is the 3D Navier-Stokes system in a bounded domain. In such a situation one cannot use directly the classical scheme of construction of a dynamical system in the phase space of initial conditions of the Cauchy problem of a given equation and find a global attractor of this dynamical system. Nevertheless, for such equations it is possible to construct a trajectory dynamical system and investigate a trajectory attractor of the corresponding translation semigroup. This universal method is applied for various types of equations arising in mathematical physics: for general dissipative reaction-diffusion systems, for the 3D Navier-Stokes system, for dissipative wave equations, for non-linear elliptic equations in cylindrical domains, and for other equations and systems. Special attention is given to using the method of trajectory attractors in approximation and perturbation problems arising in complicated models of mathematical physics. Bibliography: 96 titles.

  20. The trajectory control in the SLC linac

    International Nuclear Information System (INIS)

    Hsu, I.C.; Adolphsen, C.E.; Himel, T.M.; Seeman, J.T.

    1991-05-01

    Due to wake field effects, the trajectories of accelerated beams in the Linac should be well maintained to avoid severe beam breakup. In order to maintain a small emittance at the end of the Linac, the tolerance on the trajectory deviations become tighter when the beam intensities increase. The existing two beam trajectory correction method works well when the theoretical model agrees with the real machine lattice. Unknown energy deviations along the linac as well as wake field effects can cause the real lattice to deviate from the model. This makes the trajectory correction difficult. Several automated procedures have been developed to solve these problems. They are: an automated procedure to frequently steer the whole Linac by dividing the Linac into several small regions; an automated procedure to empirically correct the model to fit the real lattice and eight trajectory correcting feedback loops along the linac and steering through the collimator region with restricted corrector strengths and a restricted number of correctors. 6 refs., 2 figs

  1. Spatiotemporal Interpolation Methods for Solar Event Trajectories

    Science.gov (United States)

    Filali Boubrahimi, Soukaina; Aydin, Berkay; Schuh, Michael A.; Kempton, Dustin; Angryk, Rafal A.; Ma, Ruizhe

    2018-05-01

    This paper introduces four spatiotemporal interpolation methods that enrich complex, evolving region trajectories that are reported from a variety of ground-based and space-based solar observatories every day. Our interpolation module takes an existing solar event trajectory as its input and generates an enriched trajectory with any number of additional time–geometry pairs created by the most appropriate method. To this end, we designed four different interpolation techniques: MBR-Interpolation (Minimum Bounding Rectangle Interpolation), CP-Interpolation (Complex Polygon Interpolation), FI-Interpolation (Filament Polygon Interpolation), and Areal-Interpolation, which are presented here in detail. These techniques leverage k-means clustering, centroid shape signature representation, dynamic time warping, linear interpolation, and shape buffering to generate the additional polygons of an enriched trajectory. Using ground-truth objects, interpolation effectiveness is evaluated through a variety of measures based on several important characteristics that include spatial distance, area overlap, and shape (boundary) similarity. To our knowledge, this is the first research effort of this kind that attempts to address the broad problem of spatiotemporal interpolation of solar event trajectories. We conclude with a brief outline of future research directions and opportunities for related work in this area.

  2. Handling Trajectory Uncertainties for Airborne Conflict Management

    Science.gov (United States)

    Barhydt, Richard; Doble, Nathan A.; Karr, David; Palmer, Michael T.

    2005-01-01

    Airborne conflict management is an enabling capability for NASA's Distributed Air-Ground Traffic Management (DAG-TM) concept. DAGTM has the goal of significantly increasing capacity within the National Airspace System, while maintaining or improving safety. Under DAG-TM, autonomous aircraft maintain separation from each other and from managed aircraft unequipped for autonomous flight. NASA Langley Research Center has developed the Autonomous Operations Planner (AOP), an onboard decision support system that provides airborne conflict management (ACM) and strategic flight planning support for autonomous aircraft pilots. The AOP performs conflict detection, prevention, and resolution from nearby traffic aircraft and area hazards. Traffic trajectory information is assumed to be provided by Automatic Dependent Surveillance Broadcast (ADS-B). Reliable trajectory prediction is a key capability for providing effective ACM functions. Trajectory uncertainties due to environmental effects, differences in aircraft systems and performance, and unknown intent information lead to prediction errors that can adversely affect AOP performance. To accommodate these uncertainties, the AOP has been enhanced to create cross-track, vertical, and along-track buffers along the predicted trajectories of both ownship and traffic aircraft. These buffers will be structured based on prediction errors noted from previous simulations such as a recent Joint Experiment between NASA Ames and Langley Research Centers and from other outside studies. Currently defined ADS-B parameters related to navigation capability, trajectory type, and path conformance will be used to support the algorithms that generate the buffers.

  3. Growing up with Asperger’s syndrome: developmental trajectory of autobiographical memory (a clinical case study

    Directory of Open Access Journals (Sweden)

    Laetitia eBon

    2013-01-01

    Full Text Available Autobiographical memory and social cognition share common properties and both are affected in autism spectrum disorders (ASD. So far, most of the scant research in ASD has concerned adults, systematically reporting impairment of the episodic component. The only study to be conducted with children concluded that they have poorer personal semantic knowledge than typical developing children. The present study explores the development of both components of autobiographical memory in an 8-year-old boy diagnosed with Asperger’s syndrome, based on three examinations in 2007, 2008 and 2010. On each occasion, he underwent a general neuropsychological assessment including theory of mind tasks, and a specially-designed autobiographical memory task allowing us to test both the semantic and the episodic components for three lifetime periods (current year, previous year and earlier years. We observed difficulties in strategic retrieval and theory of mind, with a significant improvement between the second and third examinations. Regarding autobiographical memory, different patterns of performance were noted in all three examinations: 1 relative preservation of current-year personal knowledge, but impairment for the previous and earlier years, and 2 impairment of episodic memory for the current and previous year, but performances similar to those of controls for the earlier years. The first pattern can be explained by abnormal forgetting and by the semanticization mechanism, which needs verbal communication and social interaction to be efficient. The second pattern suggests that the development of episodic memory only reached the stage of event memory. This term refers to memory for personal events lacking in details or spatiotemporal specificity, and is usually observed in children younger than 5. We conclude that the abnormal functioning of social cognition in ASD, encompassing social and personal points of view, has an impact on both components of autobiographical memory.

  4. Bounded Rationality in the Developmental Trajectory of Environmental Target Policy in China, 1972–2016

    Directory of Open Access Journals (Sweden)

    Rui Mu

    2018-01-01

    Full Text Available This article applies the theoretical notion of “bounded rationality” to understand and to explain the updates of the Environmental Target Policy (ETP in China during 1972–2016. An analytical framework is built up by combining the phase model and the stream model in policy science in order to trace the longitudinal transformation of the ETP. In addition, the article adopts the “event sequence method” to discover the dynamics of the problem, politics, and policy streams of the target policy and to identify the evolving coupling between the different streams. It shows that China’s ETP has experienced five phases of development. For each phase the central government had its specific bounded rationality to make the crucial decision on the ETP. The decisions on the ETP in different phases were made when policy windows were open with the coupling of the problem, politics, and policy streams. As for the updates of the ETP, we find that the rationalities of the central governments in the five phases were limited by the emergent practices during the ETP implementation, which gave momentum to the central government to seek new solutions and to revise and adapt the ETP.

  5. Developmental Trajectories of Acculturation in Hispanic Adolescents: Associations with Family Functioning and Adolescent Risk Behavior

    Science.gov (United States)

    Schwartz, Seth J.; Des Rosiers, Sabrina; Huang, Shi; Zamboanga, Byron L.; Unger, Jennifer B.; Knight, George P.; Pantin, Hilda; Szapocznik, Jose

    2013-01-01

    This study examined longitudinal acculturation patterns, and their associations with family functioning and adolescent risk behaviors, in Hispanic immigrant families. A sample of 266 Hispanic adolescents (M[subscript age] = 13.4) and their primary parents completed measures of acculturation, family functioning, and adolescent conduct problems,…

  6. Developmental Trajectories of Motivation in Physical Education: Course, Demographic Differences, and Antecedents

    Science.gov (United States)

    Ntoumanis, Nikos; Barkoukis, Vassilis; Thogersen-Ntoumani, Cecilie

    2009-01-01

    This study investigated changes in student motivation to participate in physical education and some determinants of these changes over a period of 3 years. Measures were taken twice a year, from age 13 until age 15, from a sample of Greek junior high school students. Multilevel modeling analyses showed significant decreases in task-involving…

  7. Pathways to deviance: developmental trajectories of externalizing problems in dutch youth

    NARCIS (Netherlands)

    I.L. Bongers (Ilja)

    2005-01-01

    textabstractExternalizing behaviors are the most common and persistent forms of childhood problem behaviors (Campbell, 1995) and are both concurrently and prospectively related to impaired functioning in many domains (Rutter, Giller, & Hagell, 1998). Studies indicated that children and adolescents

  8. Maternal Obesity: Lifelong Metabolic Outcomes for Offspring from Poor Developmental Trajectories During the Perinatal Period.

    Science.gov (United States)

    Zambrano, Elena; Ibáñez, Carlos; Martínez-Samayoa, Paola M; Lomas-Soria, Consuelo; Durand-Carbajal, Marta; Rodríguez-González, Guadalupe L

    2016-01-01

    The prevalence of obesity in women of reproductive age is increasing in developed and developing countries around the world. Human and animal studies indicate that maternal obesity adversely impacts both maternal health and offspring phenotype, predisposing them to chronic diseases later in life including obesity, dyslipidemia, type 2 diabetes mellitus, and hypertension. Several mechanisms act together to produce these adverse health effects including programming of hypothalamic appetite-regulating centers, increasing maternal, fetal and offspring glucocorticoid production, changes in maternal metabolism and increasing maternal oxidative stress. Effective interventions during human pregnancy are needed to prevent both maternal and offspring metabolic dysfunction due to maternal obesity. This review addresses the relationship between maternal obesity and its negative impact on offspring development and presents some maternal intervention studies that propose strategies to prevent adverse offspring metabolic outcomes. Copyright © 2016 IMSS. Published by Elsevier Inc. All rights reserved.

  9. Autism Spectrum Disorders and Schizophrenia Spectrum Disorders: Excitation/Inhibition Imbalance and Developmental Trajectories

    Directory of Open Access Journals (Sweden)

    Roberto Canitano

    2017-05-01

    Full Text Available Autism spectrum disorders (ASD and schizophrenia spectrum disorders (SSD share clinical and genetic components that have long been recognized. The two disorders co-occur more frequently than would be predicted by their respective prevalence, suggesting that a complex, multifactor association is involved. However, DSM-5 maintains the distinction between ASD, with core social and communication impairments, and SSD, including schizophrenia (SCZ, with hallucinations, delusions, and thought disorder as essential features. ASD and SSD have common biological underpinnings that may emerge early in development and unfold over time. One of the hypotheses supporting the similarities in the social and cognitive disturbances of ASD and SSD relates to abnormalities in the ratio of excitatory to inhibitory cortical activity (E/I imbalance. E/I imbalance in neurodevelopmental disorders could be the consequence of abnormalities in genes coding for glutamatergic and GABAergic receptors or synaptic proteins followed by system derangements. SSD and ASD have been characterized as polygenic disorders in which to the onset and progression of disease is triggered by interactions among multiple genes. Mammalian target of rapamycin signaling is under intense investigation as a convergent altered pathway in the two spectrum disorders. Current understanding of shared and divergent patterns between ASD and SSD from molecular to clinical aspects is still incomplete and may be implemented by the research domain criteria approach.

  10. Developmental changes in the reward positivity: An electrophysiological trajectory of reward processing

    Directory of Open Access Journals (Sweden)

    Carmen N. Lukie

    2014-07-01

    Full Text Available Children and adolescents learn to regulate their behavior by utilizing feedback from the environment but exactly how this ability develops remains unclear. To investigate this question, we recorded the event-related brain potential (ERP from children (8–13 years, adolescents (14–17 years and young adults (18–23 years while they navigated a “virtual maze” in pursuit of monetary rewards. The amplitude of the reward positivity, an ERP component elicited by feedback stimuli, was evaluated for each age group. A current theory suggests the reward positivity is produced by the impact of reinforcement learning signals carried by the midbrain dopamine system on anterior cingulate cortex, which utilizes the signals to learn and execute extended behaviors. We found that the three groups produced a reward positivity of comparable size despite relatively longer ERP component latencies for the children, suggesting that the reward processing system reaches maturity early in development. We propose that early development of the midbrain dopamine system facilitates the development of extended goal-directed behaviors in anterior cingulate cortex.

  11. Toward Developmental Trajectories: A Commentary on "Assessing Measures of Mathematical Knowledge for Teaching"

    Science.gov (United States)

    Kulikowich, Jonna M.

    2007-01-01

    Operating from multiple literature bases in cognitive psychology, mathematics education, and theoretical and applied psychometrics, Schilling, Hill and their colleagues provide a systemic approach to studying the validity of scores of mathematical knowledge for teaching. This system encompasses an array of task formats and methodologies. The…

  12. Identity processes and personality traits and types in adolescence : Directionality of effects and developmental trajectories

    NARCIS (Netherlands)

    Luyckx, K.; Teppers, E.; Klimstra, T.A.; Rassart, J.

    2014-01-01

    Personality traits are hypothesized to be among the most important factors contributing to individual differences in identity development. However, longitudinal studies linking Big Five personality traits to contemporary identity models (in which multiple exploration and commitment processes are

  13. Identity Processes and Personality Traits and Types in Adolescence: Directionality of Effects and Developmental Trajectories

    Science.gov (United States)

    Luyckx, Koen; Teppers, Eveline; Klimstra, Theo A.; Rassart, Jessica

    2014-01-01

    Personality traits are hypothesized to be among the most important factors contributing to individual differences in identity development. However, longitudinal studies linking Big Five personality traits to contemporary identity models (in which multiple exploration and commitment processes are distinguished) are largely lacking. To gain more…

  14. Developmental Trajectories of Borderline Personality Disorder Symptoms and Psychosocial Functioning in Adolescence.

    Science.gov (United States)

    Wright, Aidan G C; Zalewski, Maureen; Hallquist, Michael N; Hipwell, Alison E; Stepp, Stephanie D

    2016-06-01

    In recent years, major gains toward understanding the emergence of borderline personality disorder (BPD) pathology, which is typically first noted during adolescence, have been made. Simultaneously, a profound shift has occurred in the adult personality pathology literature, in which empirical evidence rebuts the idea that personality disorders (PDs) are intractable disorders that do not develop or otherwise change over time, and therefore cannot be treated. The present study addresses a gap in our understanding of within-person change in BPD symptoms across adolescence and contributes to the limited literature on outcomes associated with adolescent BPD. Using an at-risk community sample of girls (N = 2,450), the authors used bivariate latent growth curve models to analyze the codevelopment of BPD symptoms with eight domains of psychosocial functioning (e.g., academic achievement, social skills, sexual behavior) across ages 14-17. Findings revealed moderate to strong effect sizes for the associations between BPD symptoms and every domain of psychosocial functioning, suggesting that the development of BPD was coupled with poorer outcomes across development. Controlling for depression and conduct disorder features revealed unique associations between BPD and self-perception, social skills, and sexual behavior. These results highlight the increased need for extending advancements in the adult PD literature to research on PDs in adolescence, and for greater recognition of adolescent BPD in clinical settings.

  15. Developmental programming: gestational bisphenol-A treatment alters trajectory of fetal ovarian gene expression.

    Science.gov (United States)

    Veiga-Lopez, Almudena; Luense, Lacey J; Christenson, Lane K; Padmanabhan, Vasantha

    2013-05-01

    Bisphenol-A (BPA), a ubiquitous environmental endocrine disrupting chemical, is a component of polycarbonate plastic and epoxy resins. Because of its estrogenic properties, there is increasing concern relative to risks from exposures during critical periods of early organ differentiation. Prenatal BPA treatment in sheep results in low birth weight, hypergonadotropism, and ovarian cycle disruptions. This study tested the hypothesis that gestational exposure to bisphenol A, at an environmentally relevant dose, induces early perturbations in the ovarian transcriptome (mRNA and microRNA). Pregnant Suffolk ewes were treated with bisphenol A (0.5 mg/kg, sc, daily, produced ∼2.6 ng/mL of unconjugated BPA in umbilical arterial samples of BPA treated fetuses approaching median levels of BPA measured in maternal circulation) from days 30 to 90 of gestation. Expression of steroidogenic enzymes, steroid/gonadotropin receptors, key ovarian regulators, and microRNA biogenesis components were measured by RT-PCR using RNA derived from fetal ovaries collected on gestational days 65 and 90. An age-dependent effect was evident in most steroidogenic enzymes, steroid receptors, and key ovarian regulators. Prenatal BPA increased Cyp19 and 5α-reductase expression in day 65, but not day 90, ovaries. Fetal ovarian microRNA expression was altered by prenatal BPA with 45 down-regulated (>1.5-fold) at day 65 and 11 down-regulated at day 90 of gestation. These included microRNAs targeting Sry-related high-mobility-group box (SOX) family genes, kit ligand, and insulin-related genes. The results of this study demonstrate that exposure to BPA at an environmentally relevant dose alters fetal ovarian steroidogenic gene and microRNA expression of relevance to gonadal differentiation, folliculogenesis, and insulin homeostasis.

  16. Learning to Read in Williams Syndrome and Down Syndrome: Syndrome-Specific Precursors and Developmental Trajectories

    Science.gov (United States)

    Steele, Ann; Scerif, Gaia; Cornish, Kim; Karmiloff-Smith, Annette

    2013-01-01

    Background: In typical development, early reading is underpinned by language skills, like vocabulary and phonological awareness (PA), as well as taught skills like letter knowledge. Less is understood about how early reading develops in children with neurodevelopmental disorders who display specific profiles of linguistic strengths and weaknesses,…

  17. Developmental Trajectories of (Cyber)Bullying Perpetration and Social Intelligence during Early Adolescence

    Science.gov (United States)

    Pabian, Sara; Vandebosch, Heidi

    2016-01-01

    The purpose of the present study is to examine bullying perpetration and social intelligence (SI), which is a sociocognitive characteristic that has been proposed as a possible regulator of traditional and cyberbullying. We compared SI for perpetrators and nonperpetrators of traditional bullying and/or cyberbullying and examined longitudinal…

  18. Transitions in Friendship Attachment During Adolescence are Associated With Developmental Trajectories of Depression Through Adulthood.

    Science.gov (United States)

    Cook, Stephanie H; Heinze, Justin E; Miller, Alison L; Zimmerman, Marc A

    2016-03-01

    Forming secure friendship attachments during adolescence are important for mental health; few, however, have specifically examined the ways in which the transitions in attachment during adolescence may influence future mental health outcomes among African Americans. The present study examines how transitions in attachment in adolescence predicted changes in depression symptoms from late adolescents through adulthood in an African-American sample. We used growth curve modeling to examine the association between transitions in friendship attachment and changes in depression symptoms in adulthood. At age 16 years, 346 (64.0%) adolescents reported secure attachment with 195 (36.0%) reporting either avoidant or resistant attachment. At age 17 years, 340 (62.9%) reported secure attachment and 201 (37.2%) reported avoidant or resistant attachment. The largest percentage of participants (46.2%) reported stable-secure attachment across the two time points. Results of the growth model indicated that adolescents who reported a stable-secure attachment style had lower levels of depression symptoms during adulthood than those individuals who transitioned from secure-to-insecure, from insecure-to-secure, or were in the stable-insecure group. Interestingly enough, individuals in both the attachment transition groups had a faster declining rate of depression symptoms over time compared to the two stability groups. Data support existing research showing an association between transitions in attachment during adolescence and depression through adulthood. Furthermore, these study findings suggest there may be protective features associated with transitioning between attachment styles during adolescence on later depression, compared to African Americans who remain stable in their attachment style. Copyright © 2016 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

  19. Developmental Trajectories From Birth to School Age in Healthy Term-Born Children

    NARCIS (Netherlands)

    Roze, E.; Meijer, Lisethe; Van Braeckel, K.N.J.A.; Ruiter, S.A.J.; Bruggink, J.L.M.; Bos, A.F.

    OBJECTIVE: To determine the stability of the scores obtained on tests of motor development from birth until school age in healthy, term singletons and to determine if early motor scores are associated with more complex cognitive functions at school age, such as attention and memory. PATIENTS AND

  20. Developmentally Appropriate Peace Education Curricula

    Science.gov (United States)

    Lewsader, Joellen; Myers-Walls, Judith A.

    2017-01-01

    Peace education has been offered to children for decades, but those curricula have been only minimally guided by children's developmental stages and needs. In this article, the authors apply their research on children's developmental understanding of peace along with peace education principles and Vygotsky's sociocultural theory to present…