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Developmental Contexts (developmental + context)
Selected AbstractsECOLOGICAL AND DEVELOPMENTAL CONTEXT OF NATURAL SELECTION: MATERNAL EFFECTS AND THERMALLY INDUCED PLASTICITY IN THE FROG BOMBINA ORIENTALISEVOLUTION, Issue 1 2006Robert H. Kaplan Abstract Variation in fitness generated by differences in functional performance can often be traced to morphological variation among individuals within natural populations. However, morphological variation itself is strongly influenced by environmental factors (e.g., temperature) and maternal effects (e.g., variation in egg size). Understanding the full ecological context of individual variation and natural selection therefore requires an integrated view of how the interaction between the environment and development structures differences in morphology, performance, and fitness. Here we use naturally occurring environmental and maternal variation in the frog Bombina orientalis in South Korea to show that ovum size, average temperature, and variance in temperature during the early developmental period affect body sizes, shapes, locomotor performance, and ultimately the probability of an individual surviving interspecific predation in predictable but nonadditive ways. Specifically, environmental variability can significantly change the relationship between maternal investment in offspring and offspring fitness so that increased maternal investment can actually negatively affect offspring over a broad range of environments. Integrating environmental variation and developmental processes into traditional approaches of studying phenotypic variation and natural selection is likely to provide a more complete picture of the ecological context of evolutionary change. [source] Effects of prenatal visual stimulation on growth and heart rate in bobwhite quail (Colinus virginianus)DEVELOPMENTAL PSYCHOBIOLOGY, Issue 4 2006Merry J. Sleigh Abstract This study examined the effects of prenatal visual stimulation on bobwhite quail embryos' growth and heart rate. No differences in growth rate were found between embryos exposed to visual stimulation during the late prenatal period and control embryos. Embryos exposed to visual stimulation throughout incubation maintained lower heart rates in response to visual stimulation than did naïve embryos. In a subsequent experiment, naïve embryos that underwent an egg-opening procedure exhibited heart rates that were lower than embryos measured in intact eggshells. Embryos in opened eggs maintained lower heart rates than comparison embryos across time; however, a less invasive egg-opening procedure led to a quicker heart rate recovery than did a more invasive egg-opening procedure. These findings indicate that prenatal heart rate responses may be mediated by multiple features of the organism's developmental context, including intensity and duration of sensory stimulation. © 2006 Wiley Periodicals, Inc. Dev Psyshobiol 48: 315,324, 2006. [source] How Elephants are Opening Doors: Developmental Neuroethology, Attachment and Social ContextETHOLOGY, Issue 5 2007G. A. Bradshaw Ethology's renewed interest in developmental context coincides with recent insights from neurobiology and psychology on early attachment. Attachment and social learning are understood as fundamental mechanisms in development that shape core processes responsible for informing behaviour throughout a lifetime. Each field uniquely contributes to the creation of an integrated model and encourages dialogue between Tinbergen's four analytical levels: ethology in its underscoring of social systems of behaviour and context, psychology in its emphasis on socio-affective attachment transactions, and neuroscience in its explication of the coupled development of brain and behaviour. We review the relationship between developmental context and behaviour outcome as a topic shared by the three disciplines, with a specific focus on underlying neuroethological mechanisms. This interdisciplinary convergence is illustrated through the example of abnormal behaviour in wild African elephants (Loxodonta africana) that has been systematically observed in human-caused altered social contexts. Such disruptions impair normative socially mediated neuroendocrinological development leading to psychobiological dysregulation that expresses as non-normative behaviour. Aberrant behaviour in wild elephants provides a critical field example of what has been established in ex situ and clinical studies but has been largely absent in wild populations: a concrete link between effects of human disturbance on social context, and short- and long-term neuroethology. By so doing, it brings attention to the significant change in theories of behaviour that has been occurring across disciplines , namely, the merging of psychobiological and ethological perspectives into common, cross-species, human inclusive models. [source] Characterization of the Drosophila myeloid leukemia factorGENES TO CELLS, Issue 12 2006Séverine Martin-Lannerée In human, the myeloid leukemia factor 1 (hMLF1) has been shown to be involved in acute leukemia, and mlf related genes are present in many animals. Despite their extensive representation and their good conservation, very little is understood about their function. In Drosophila, dMLF physically interacts with both the transcription regulatory factor DREF and an antagonist of the Hedgehog pathway, Suppressor of Fused, whose over-expression in the fly suppresses the toxicity induced by polyglutamine. No connection between these data has, however, been established. Here, we show that dmlf is widely and dynamically expressed during fly development. We isolated and analyzed the first dmlf mutants: embryos lacking maternal dmlf product have a low viability with no specific defect, and dmlf - , adults display weak phenotypes. We monitored dMLF subcellular localization in the fly and cultured cells. We were able to show that, although generally nuclear, dMLF can also be cytoplasmic, depending on the developmental context. Furthermore, two differently spliced variants of dMLF display differential subcellular localization, allowing the identification of regions of dMLF potentially important for its localization. Finally, we demonstrate that dMLF can act developmentally and postdevelopmentally to suppress neurodegeneration and premature aging in a cerebellar ataxia model. [source] An examination of frequent nursing interventions and outcomes in an adolescent psychiatric inpatient unitINTERNATIONAL JOURNAL OF MENTAL HEALTH NURSING, Issue 5 2009Candace Bobier ABSTRACT:, Little is known about which nursing interventions used in adolescent psychiatric inpatient treatment demonstrate improvements in outcome in the ,real world' setting, despite an increase in external outcomes reporting requirements. This paper examines nursing and other multidisciplinary interventions commonly used at the Youth Inpatient Unit, Christchurch, New Zealand, in relation to improvements in outcomes as measured by the Health of the Nation Outcome Scales for Children and Adolescents, utilizing data gathered prospectively as part of an ongoing quality assurance and outcomes project. We found the majority of interventions investigated were utilized equally across diagnostic groups, although stress management and problem-solving education was used more for patients with mixed affective disorders. Further, the results contribute to growing evidence toward the value of providing medication and problem-solving education to this population. Mental health nurses working with children and adolescents should be supported to utilize and develop their unique skill set to offer targeted interventions and to examine their practice to identify the most valuable interventions for their patients within this developmental context. [source] The Hypothalamic Insulin-Like Growth Factor-1 Receptor and Its Relationship to Gonadotropin-Releasing Hormones Neurones During Postnatal DevelopmentJOURNAL OF NEUROENDOCRINOLOGY, Issue 2 2004S. S. Daftary Abstract Reproduction in vertebrates is controlled by hypophysiotropic gonadotropin-releasing hormone (GnRH) neurones. Pulsatile GnRH release increases during reproductive development, resulting in the onset and progression of puberty and, ultimately, the acquisition and maintenance of adult reproductive function. These changes in GnRH release are largely due to inputs to GnRH cells from other factors, including the neurotrophic factor, insulin-like growth factor-1 (IGF-1). Here, molecular studies were undertaken to quantify expression of IGF-1 receptor (IGF-1R) mRNA in the preoptic area-anterior hypothalamus (POA-AH) and mediobasal hypothalamus (MBH)-median eminence (ME), the sites of GnRH perikarya and neuroterminals, respectively. Immunocytochemical studies were also carried out to study the anatomical relationship between the IGF-1R and GnRH neurones. Experiments were performed in a developmental context using neonatal (P5), peripubertal (,P30) and adult (P60) male and female mice. We found that IGF-1R mRNA levels in the POA-AH were significantly different among all age groups, with levels higher at P60 then P5 or ,P30. Levels of IGF-1R mRNA in the MBH-ME were lower at P5 than ,P30 or P60. Qualitative observations suggested that IGF-1R immunoreactivity in POA-AH increased from P5 through P60. Quantitative double-label immunocytochemistry studies showed that GnRH perikarya expressed IGF-1R. Taken together, the results demonstrate expression of, and developmental changes in, IGF-1R gene and protein in brain regions containing GnRH and other neuroendocrine cells. Moreover, the novel finding that the IGF-1R is expressed on GnRH perikarya in vivo suggests a potential direct anatomical locus where IGF-1 can regulate reproductive development and function. [source] Mixed-Gender Groups, Dating, and Romantic Relationships in Early AdolescenceJOURNAL OF RESEARCH ON ADOLESCENCE, Issue 2 2004Jennifer Connolly This study examined dating-stage and developmental-contextual models of romantic relationships during early adolescence. Same-gender friendships, affiliation with mixed-gender groups, dating, and romantic relationships were investigated in a sample of 1,284 young adolescents of diverse ethnocultural backgrounds. Data were collected cross-sectionally in Grades 5 through 8, as well as longitudinally in the fall and spring of an academic year. Consistent with a stage model, affiliation with mixed-gender groups and dating were qualitatively distinct activities that were sequentially organized and facilitated the progression from same-gender friendships to dyadic romantic relationships. The results also provide insights on how the developmental context may alter stage pathways: Dating activities were incorporated with mixed-gender affiliations, group-based romantic stages showed more stability than other stages, and the ethnocultural context influenced romantic timing. Finally, results indicated that participation in romantic activities heightened adolescents' future interest in having a romantic relationship. [source] Evolutionary Perspectives on the Development of Social ExchangesNEW DIRECTIONS FOR CHILD & ADOLESCENT DEVELOPMENT, Issue 95 2002Brad E. Sheese Evolutionary theory suggests that developmental context and genetic relatedness may fundamentally alter social exchange processes. [source] Assessing the Risks Presented by ParentsCHILD AND ADOLESCENT MENTAL HEALTH, Issue 3 2001Ian Partridge The establishment, operation and theoretical basis of a multi-disciplinary, Tier 3, risk assessment team based in a Child and Adolescent Mental Health Service (CAMHS) is described. The work is based on the premise that a multi-disciplinary team, with a degree of statutory independence, assessing forensic issues within a systemic and developmental context, offers a useful contribution to the comprehensive assessment of risk and provides a valuable and valued service to statutory agencies and the courts. The team is used by Social Services Departments and the courts as an independent assessor of the risk parents and potential carers pose to children. An evaluation of 39 referrals, carried out over the last 3 years of operation of the parenting risk assessment team, is given. [source] Differential expression of polycomb repression complex 1 (PRC1) members in the developing mouse brain reveals multiple complexesDEVELOPMENTAL DYNAMICS, Issue 9 2006Tanja Vogel Abstract Polycomb group (PcG) genes are regulators of body segmentation and cell growth, therefore being important players during development. PcG proteins form large complexes (PRC) that fulfil mostly repressive regulative functions on homeotic gene expression. Although expression of PcG genes in the brain has been noticed, the involvement of PcG genes in the processes of brain development is not understood. In this study, we analysed the expression patterns of PRC1 complex members to reveal PcG proteins that might be relevant for mouse brain development. Using in situ hybridisation, we show PRC1 activity in proliferative progenitor cells during neurogenesis, but also in maturated neuronal structures. PRC1 complex compositions vary in a spatial and temporal controlled manner during mouse brain development, providing cellular tools to act in different developmental contexts of cell proliferation, cell fate determination, and differentiation. Developmental Dynamics 235:2574,2585, 2006. © 2006 Wiley-Liss, Inc. [source] Functional analysis of murine CBF1 during Drosophila developmentDEVELOPMENTAL DYNAMICS, Issue 4 2006Markus Kaspar Abstract Transcription factors of the CSL family are the main mediators of the Notch signalling pathway. The CSL factor in Drosophila is called Suppressor of Hairless (Su(H)) and it has been shown that it acts as a transcriptional repressor in the absence of a Notch signal and as a transcriptional activator in its presence in several developmental contexts. Furthermore, recent data suggest that Su(H) can also activate and maintain transcription of some target genes in a Notch-independent manner. However, although it has been shown that the mammalian CSL ortholog, CBF1, acts as a repressor of transcription in cell culture experiments, so far in vivo evidence for such a function has been lacking. Moreover, it is not known whether CBF1 can activate transcription in a Notch-independent manner, just like Su(H). Here we have investigated these questions by introducing murine CBF1 (mCBF1) and asked whether it can functionally replace Su(H) during Drosophila development. We found that this is indeed the case. We show that mCBF1 can act as a repressor of transcription and can activate and maintain the expression of some target genes in a Notch-independent manner. Our results, therefore, indicate that CBF1 can exert these functions also in its normal context, that is during mammalian development. Developmental Dynamics 235:918,927, 2006. © 2006 Wiley-Liss, Inc. [source] An ecdysteroid-inducible insulin-like growth factor-like peptide regulates adult development of the silkmoth Bombyx moriFEBS JOURNAL, Issue 5 2009Naoki Okamoto Insulin-like growth factors (IGFs) play essential roles in fetal and postnatal growth and development of mammals. They are secreted by a wide variety of tissues, with the liver being the major source of circulating IGFs, and regulate cell growth, differentiation and survival. IGFs share some biological activities with insulin but are secreted in distinct physiological and developmental contexts, having specific functions. Although recent analyses of invertebrate genomes have revealed the presence of multiple insulin family peptide genes in each genome, little is known about functional diversification of the gene products. Here we show that a novel insulin family peptide of the silkmoth Bombyx mori, which was purified and sequenced from the hemolymph, is more like IGFs than like insulin, in contrast to bombyxins, which are previously identified insulin-like peptides in B. mori. Expression analysis reveals that this IGF-like peptide is predominantly produced by the fat body, a functional equivalent of the vertebrate liver and adipocytes, and is massively released during pupa,adult development. Studies using in vitro tissue culture systems show that secretion of the peptide is stimulated by ecdysteroid and that the secreted peptide promotes the growth of adult-specific tissues. These observations suggest that this peptide is a Bombyx counterpart of vertebrate IGFs and that functionally IGF-like peptides may be more ubiquitous in the animal kingdom than previously thought. Our results also suggest that the known effects of ecdysteroid on insect adult development may be in part mediated by IGF-like peptides. [source] Generation of a Snail1 (Snai1) conditional null alleleGENESIS: THE JOURNAL OF GENETICS AND DEVELOPMENT, Issue 1 2006Stephen A. Murray Abstract Members of the Snail gene superfamily, which encode zinc finger transcriptional repressors, play critical roles in the establishment of the vertebrate body plan. The Snail1 (Snai1) gene promotes epithelial,mesenchymal transitions during development and disease progression, and Snai1 null mouse embryos exhibit defects in gastrulation. However, the early embryonic lethality of Snai1 null embryos precludes the study of Snai1 function in other developmental contexts or diseases. To overcome this restriction, we generated a Snai1 conditional null allele by flanking the promoter and first two exons of the Snai1 gene with loxP sites. Cre-mediated deletion of the Snai1flox allele generates the Snai1del2 allele, which behaves genetically as a Snai1 null allele. This conditional null allele will enable investigation of Snai1 function in a variety of developmental and pathological contexts. genesis 44:7,11, 2006. © 2006 Wiley-Liss, Inc. [source] Do maternal stress and home environment mediate the relation between early income-to-need and 54-months attentional abilities?INFANT AND CHILD DEVELOPMENT, Issue 5 2007Janean E. Dilworth-Bart Abstract Using Ecological Systems Theory and stage sequential modelling procedures for detecting mediation, this study examined how early developmental contexts impact preschoolers' performances on a measure of sustained attention and impulse control. Data from 1273 European-American and African-American participants in the NICHD Study of Early Child Care were used to identify the potential mediators of the relation between early household income-to-need (INR) and 54-month impulsivity and inattention. Exploratory analyses were also conducted to determine whether the relationships between early income, home environment, parenting stress, and the outcome variables differ for African-American versus European-American-American children. We found modest support for the study hypothesis that 36-month home environment quality mediated the INR/attention relationship. INR accounted for more home environment score variance and home environment accounted for more Impulsivity score variance for African-American children. Home environments were related to inattention in the European-American, but not African-American, group. Copyright © 2007 John Wiley & Sons, Ltd. [source] Romantic Relationships among Immigrant Adolescents1INTERNATIONAL MIGRATION REVIEW, Issue 2 2007Rosalind Berkowitz King We examine the importance of the family and friendship group as two crucial developmental contexts for adolescent relationship experiences. We focus particularly on immigrant adolescents who make up an increasing proportion of the youth population and who come from cultural contexts with stronger family traditions than native-born adolescents. Using data from the National Longitudinal Study of Adolescent Health, we model the characteristics associated with having romantic relationships and participating in sex-related activities within relationships for immigrant adolescents, children of immigrants and adolescents in native-born families. First generation adolescents are less likely to enter romantic relationships than adolescents in native-born families, but those who do participate engage in similar sex-related activities as native-born youth. This evidence suggests that immigrant youth who enter romantic relationships are selective of the more assimilated to native adolescent norms of heterosexual behavior. The peer group is especially important for immigrant adolescents because it provides opportunities for romantic relationship involvement. [source] Furthering the Understanding of Parent,Child Relationships: A Nursing Scholarship Review Series.JOURNAL FOR SPECIALISTS IN PEDIATRIC NURSING, Issue 3 2010Adolescent, Child Relationships, Part 5: Parent, Teen Parent PURPOSE., The purpose of this paper is to examine nursing's contribution to understanding the parent,adolescent and the teen parent,child relationships. CONCLUSION., Relationships between parents and adolescents may reflect turmoil and affect adolescents' health and development. The social and developmental contexts for teen parenting are powerful and may need strengthening. Several interventions to help teen mothers interact sensitively with their infants have been developed and tested. PRACTICE IMPLICATIONS., Nurse researchers have begun to provide evidence for practitioners to use in caring for families of adolescents and teen parents to acquire interaction skills that, in turn, may promote optimal health and development of the child. [source] Harnessing the power of sibling relationships as a tool for optimizing social,emotional developmentNEW DIRECTIONS FOR CHILD & ADOLESCENT DEVELOPMENT, Issue 126 2009Elizabeth A. Stormshak Sibling relationships provide one of the most stable and powerful developmental contexts for the transmission of both prosocial and antisocial behavior. As a source of support and skill development, sibling relationships can build competence in self-regulation and emotional understanding. However, sibling relationships marked by antisocial behavior, substance use, and conflict place children at risk for a host of negative outcomes. Family relationship features, particularly parenting practices and discord, contribute strongly to both the quality of sibling relationships and children's well-being. Our review of intervention strategies reveals that the potential of sibling relationships to promote socioemotional development may be best realized through family-centered approaches that build prosocial sibling interactions, curtail child behavior problems, and strengthen parenting. [source] Modelling polar auxin transport in developmental patterningPLANT BIOLOGY, Issue 2010F. Santos Abstract Auxin interacts with its own polar transport to influence cell polarity and tissue patterning. Research over the past decade has started to deliver new insights into the molecular mechanisms that drive and regulate polar auxin transport. The most prominent auxin efflux protein, PIN1, has subsequently become a crucial component of auxin transport models because it is now known to direct auxin flow and maintain local auxin gradients. Recent molecular and genetic experiments have allowed the formulation of conceptual models that are able to interpret the role of (i) auxin, (ii) its transport, and (iii) the dynamics of PIN1 in generating temporal and spatial patterns. Here we review the current mathematical models of patterning in two specific developmental contexts: lateral shoot and vein formation, focusing on how these models can help to untangle the details of auxin transport-mediated patterning. [source] Living Arrangements and Children's Development in Low-Income White, Black, and Latino FamiliesCHILD DEVELOPMENT, Issue 6 2007E. Michael Foster This article uses longitudinal data from approximately 2,000 low-income families participating in the national evaluation of the Comprehensive Child Development Program to examine the associations between preschool children's living arrangements and their cognitive achievement and emotional adjustment. The analysis distinguishes families in which children live only with their mothers from children who live in biological father, blended, and multigenerational households. Linkages are examined separately for White, Black, and Latino children. Fixed effects regression techniques reveal few significant associations between living arrangements and child development. These findings suggest that substantial diversity exists in the developmental contexts among children living in the same family structure. Policies seeking to change the living arrangements of low-income children may do little to improve child well-being. [source] | |||||||||||||||||||