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Developmental Models (developmental + models)
Selected AbstractsCHARNIA AT 50: DEVELOPMENTAL MODELS FOR EDIACARAN FRONDSPALAEONTOLOGY, Issue 1 2008JONATHAN B. ANTCLIFFE Abstract:, Correct interpretation of the Ediacara biota is critical to our understanding of the dramatic events at the base of the Cambrian. We review here the history of thought and examine new laser images of the holotype of Charnia masoniFord, 1958, of the Ediacara biota, in terms of growth and development. Growth and development are argued to provide critical tools for understanding this and other enigmatic fossil groups. We show that Charnia cannot be related to the modern cnidarian group, the sea pens, with which it has for so long been compared, because they have opposite growth polarities. This is shown by our work on material collected by HMS challenger. Recent evolutionary studies also show that sea pens are a highly derived group of actively burrowing cnidarians that are likely to have evolved later than the Palaeozoic. The traditional paradigm of translating Phanerozoic animal phyla back into the Ediacaran is therefore questioned. [source] From Piaget to Specific Genevan Developmental ModelsCHILD DEVELOPMENT PERSPECTIVES, Issue 1 2008Stéphan Desrochers ABSTRACT,Today, the ideas of Piaget and his numerous collaborators are rarely taken into consideration in psychologists' explanations of the development of children's cognitive abilities. The goal of this article was to promote 2 specific Genevan developmental models relating to children's understanding of number and to their understanding of physical causality and, in exploring these models, to demonstrate that new post-Piagetian empirical findings do not allow the outright rejection of Piagetian approaches. [source] Practitioner Review: Psychological Management of Anxiety Disorders in ChildhoodTHE JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY AND ALLIED DISCIPLINES, Issue 8 2001Mark R. Dadds Many anxiety problems begin in childhood and are a common form of psychological problem that can be highly distressing and associated with a range of social impairments. Thus, skills for conceptualising, assessing, and treating childhood anxiety problems should be in the repertoire of all child mental health specialists. This paper reviews psychosocial treatments for the most common anxiety disorders in children and adolescents. Developmental models of anxiety disorders emphasise maximum risk in children with shy or inhibited temperaments who are exposed to high family anxiety and avoidance, and/or acutely distressing experiences. As children mature these temperamental and environmental experiences are internalised to low self-competence and high threat expectancy. Both individual or group-based interventions utilising cognitive-behavioural strategies to address multiple risk factors are highly efficacious and family involvement can contribute to positive outcomes. Guidelines for assessment and treatment are presented, and suggestions are made for effectively managing clinical process. [source] Mediator effects in the social development model: an examination of constituent theoriesCRIMINAL BEHAVIOUR AND MENTAL HEALTH, Issue 4 2005Eric C. Brown Background The social development model (SDM) provides an explanatory framework for the progression of antisocial behaviour in children and adolescents. Although previous research has assessed the predictive validity of the model, alternative associations based on the SDM's constituent theories have not been examined. Method Using structural equation modelling, a series of direct paths was examined for mediation by SDM constructs. Data for the study consisted of teacher-, parent- and self-report of 1016 fourth- and fifth-grade students from the Raising Healthy Children project, a longitudinal etiological study with an embedded preventive intervention. Results Four of the seven paths examined were partially or totally mediated by SDM constructs. Specifically, the relationship between prosocial bonding and adolescent antisocial behaviour, as hypothesized by social control theory, was fully mediated by prosocial beliefs. As hypothesized by social learning theory, students' socioemotional and cognitive skills significantly predicted antisocial behaviour, independent of partial mediation through rewards, bonding and beliefs. As hypothesized by differential association theory, involvement with both prosocial and antisocial persons was directly associated with respective prosocial and antisocial beliefs, independent of partial mediation through rewards and bonding. Conclusions These findings suggest additional associations that are not currently specified in the SDM and underscore the importance of re-examining hypotheses from constituent theories when integrating developmental models of antisocial behaviour. Copyright © 2005 John Wiley & Sons, Ltd. [source] Ventral otic cell lines as developmental models of auditory epithelial and neural precursorsDEVELOPMENTAL DYNAMICS, Issue 4 2004G. Lawoko-Kerali Abstract Conditionally immortal cell lines were established from the ventral otocyst of the Immortomouse at embryonic day 10.5 and selected to represent precursors of auditory sensory neural and epithelial cells. Selection was based upon dissection, tissue-specific markers, and expression of the transcription factor GATA3. Two cell lines expressed GATA3 but possessed intrinsically different genetic programs under differentiating conditions. US/VOT-E36 represented epithelial progenitors with potential to differentiate into sensory and nonsensory epithelial cells. US/VOT-N33 represented migrating neuroblasts. Under differentiating conditions in vitro the cell lines expressed very different gene expression profiles. Expression of several cell- and tissue-specific markers, including the transcription factors Pax2, GATA3, and NeuroD, differed between the cell lines in a pattern consistent with that observed between their counterparts in vivo. We suggest that these and other conditionally immortal cell lines can be used to study transient events in development against different backgrounds of cell competence. Developmental Dynamics 231:801,814, 2004. © 2004 Wiley-Liss, Inc. [source] Trajectories of smoking among freshmen college students with prior smoking history and risk for future smoking: data from the University Project Tobacco Etiology Research Network (UpTERN) studyADDICTION, Issue 9 2008Craig R. Colder ABSTRACT Aims Little is known about smoking during the transition to college. The current study examined trajectories of smoking among college freshmen, how trajectories predicted later smoking and the social context of smoking. Design Weekly assessments of daily smoking were collected via the web during the first year of college for a large cohort with a previous history of smoking. Participants and setting A total of 193 college freshmen from a large public university with a previous history of smoking who smoked frequently enough to be included in trajectory analysis. Measurements Measures included weekly reports of daily smoking, family smoking, perceived peer attitudes and smoking, social norms and social smoking environment. Findings Seven trajectories were identified: one of low-level sporadic smoking, one of low-level smoking with a small increase during the year, two classes with a substantial decrease during the year, two classes with relatively small decreases and one class with a substantial increase in smoking. Trajectories of smoking in the freshman year predicted levels of sophomore year smoking, and some social context variables tended to change as smoking increased or decreased for a given trajectory class. Conclusions The transition into college is marked by changes in smoking, with smoking escalating for some students and continuing into the sophomore year. Shifts in social context that support smoking were associated with trajectories of smoking. Despite the focus of developmental models on smoking in early adolescence, the transition into college warrants further investigation as a dynamic period for smoking. [source] Netrin-1 receptor-deficient mice show enhanced mesocortical dopamine transmission and blunted behavioural responses to amphetamineEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 11 2007Alanna Grant Abstract The mesocorticolimbic dopamine (DA) system is implicated in neurodevelopmental psychiatric disorders including schizophrenia but it is unknown how disruptions in brain development modify this system and increase predisposition to cognitive and behavioural abnormalities in adulthood. Netrins are guidance cues involved in the proper organization of neuronal connectivity during development. We have hypothesized that variations in the function of DCC (deleted in colorectal cancer), a netrin-1 receptor highly expressed by DA neurones, may result in altered development and organization of mesocorticolimbic DA circuitry, and influence DA function in the adult. To test this hypothesis, we assessed the effects of reduced DCC on several indicators of DA function. Using in-vivo microdialysis, we showed that adult mice that develop with reduced DCC display increased basal DA levels in the medial prefrontal cortex and exaggerated DA release in response to the indirect DA agonist amphetamine. In contrast, these mice exhibit normal levels of DA in the nucleus accumbens but significantly blunted amphetamine-induced DA release. Concomitantly, using conditioned place preference, locomotor activity and prepulse inhibition paradigms, we found that reduced DCC diminishes the rewarding and behavioural-activating effects of amphetamine and protects against amphetamine-induced deficits in sensorimotor gating. Furthermore, we found that adult DCC-deficient mice exhibit altered dendritic spine density in layer V medial prefrontal cortex pyramidal neurones but not in nucleus accumbens medium spiny neurones. These findings demonstrate that reduced DCC during development results in a behavioural phenotype opposite to that observed in developmental models of schizophrenia and identify DCC as a critical factor in the development of DA function. [source] Modularity of the rodent mandible: Integrating bones, muscles, and teethEVOLUTION AND DEVELOPMENT, Issue 6 2008Miriam Leah Zelditch Summary Several models explain how a complex integrated system like the rodent mandible can arise from multiple developmental modules. The models propose various integrating mechanisms, including epigenetic effects of muscles on bones. We test five for their ability to predict correlations found in the individual (symmetric) and fluctuating asymmetric (FA) components of shape variation. We also use exploratory methods to discern patterns unanticipated by any model. Two models fit observed correlation matrices from both components: (1) parts originating in same mesenchymal condensation are integrated, (2) parts developmentally dependent on the same muscle form an integrated complex as do those dependent on teeth. Another fits the correlations observed in FA: each muscle insertion site is an integrated unit. However, no model fits well, and none predicts the complex structure found in the exploratory analyses, best described as a reticulated network. Furthermore, no model predicts the correlation between proximal parts of the condyloid and coronoid, which can exceed the correlations between proximal and distal parts of the same process. Additionally, no model predicts the correlation between molar alveolus and ramus and/or angular process, one of the highest correlations found in the FA component. That correlation contradicts the basic premise of all five developmental models, yet it should be anticipated from the epigenetic effects of mastication, possibly the primary morphogenetic process integrating the jaw coupling forces generated by muscle contraction with those experienced at teeth. [source] Trauma focus group therapy for combat-related PTSD: An updateJOURNAL OF CLINICAL PSYCHOLOGY, Issue 8 2002David W. Foy Individual cognitive,behavioral therapy involving directed exposure to memories of traumatic events has been found to be effective in treating posttraumatic stress disorder. In this article, we present updated information on an alternative group form of exposure therapy: manualized trauma-focus group therapy (TFGT), designed as an efficient means of conducting directed exposure. We describe the cognitive,behavioral and developmental models from which the approach was derived, present an overview of session topics and a case illustration, provide guidelines for referring individuals to TFGT, and offer suggestions for future research. © 2002 Wiley Periodicals, Inc. J Clin Psychol/In Session 58: 907,918, 2002. [source] Spelling development in 6,11-year-old Greek-speaking Cypriot childrenJOURNAL OF RESEARCH IN READING, Issue 3 2010Nataly Loizidou-Ieridou The aim of the present study was to examine the spelling development of Greek-speaking children in the early school grades. Although Greek orthography is regular for reading, it is much less transparent as far as spelling is concerned. Spelling development was investigated using a word spelling task designed to explore the effects of word length, familiarity and spelling regularity. One hundred and fifty normally developing primary school children living in Cyprus took part in the study. Results suggest that the children employed both phonological and lexical strategies in spelling Greek words. Results indicated that sub-lexical procedures were more marked for younger children, whereas lexical processing was employed more widely by older children. The findings are interpreted in terms of stage developmental models. [source] Research Review: The importance of callous-unemotional traits for developmental models of aggressive and antisocial behaviorTHE JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY AND ALLIED DISCIPLINES, Issue 4 2008Paul J. Frick The current paper reviews research suggesting that the presence of a callous and unemotional interpersonal style designates an important subgroup of antisocial and aggressive youth. Specifically, callous-unemotional (CU) traits (e.g., lack of guilt, absence of empathy, callous use of others) seem to be relatively stable across childhood and adolescence and they designate a group of youth with a particularly severe, aggressive, and stable pattern of antisocial behavior. Further, antisocial youth with CU traits show a number of distinct emotional, cognitive, and personality characteristics compared to other antisocial youth. These characteristics of youth with CU traits have important implications for causal models of antisocial and aggressive behavior, for methods used to study antisocial youth, and for assessing and treating antisocial and aggressive behavior in children and adolescents. [source] Key phenological events in globe artichoke (Cynara cardunculus var.scolymus) developmentANNALS OF APPLIED BIOLOGY, Issue 3 2009A. Virdis Abstract A priority for the field vegetable grower is to be able to schedule a regular supply of product throughout the growing season. This requires a predictive framework, based on the identification of key developmental events of the crop, and an understanding of how genotypic and environmental factors interact to determine plant development. Four globe artichoke (Cynara cardunculus var. scolymus) cultivars, representing the existing phenological range, were grown in a field experiment, and a range of environmental conditions was imposed by varying both the timing of the first irrigation (which determines the initiation of regrowth) and by repeating the experiment across two locations and 2 years. The timing of the appearance of the main stem capitulum was sensitive to both the growing environment and the cultivar. These differences persisted till flowering and were correlated with final leaf number. As the plant developed, the phyllochron decreased, resulting in three values of phyllochron, each of which was responsive to genotype, and hardly to environment. The timing of the first change in phyllochron was associated with the final leaf number and the appearance of the capitulum. For all the cultivars, the rate of development fell and the final leaf number increased as the length of the photoperiod increased. The later flowering cultivars shared a similar vernalisation requirement, but ,Spinoso sardo' did not require a cold period to flower. Leaf length reached a peak before the beginning of stem elongation, and maximum leaf length was correlated with final leaf number. The sensitiveness of the phyllochron to the genotype, and of the number of leaves and the timing of the appearance of the capitulum to both genotype and environment makes them suitable as variables in developmental models. The importance of the final number of leaves is not only because of its phenological significance, but also because of its effect on the ability of the canopy to intercept radiation. [source] | |||||||||||||||||||||||||