Observational studies of breakfast frequency in children and adults suggest an inverse (protective) association between the frequency of eating breakfast and the risk for obesity and chronic diseases ...such as type 2 diabetes. More prospective studies with stronger designs are needed, as are experimental studies on this topic. In addition, above and beyond breakfast frequency, the roles of dietary quality and composition need to be studied in the context of eating or skipping breakfast. Experimental studies are also necessary to rigorously test causality and biological mechanisms. Therefore, we conducted 2 pilot experimental studies to examine some of the effects of breakfast skipping and breakfast composition on blood glucose and appetite in children and adults. Our results suggest that breakfast frequency and quality may be related in causal ways to appetite controls and blood sugar control, supporting the hypothesis that the breakfast meal and its quality may have important causal implications for the risk of obesity and type 2 diabetes.
Extant literature in developmental psychology has documented the co-occurrence of aggressive and affiliative behaviors with various measures of social dominance. While these findings have been taken ...as evidence for the functional value of aggression, they have not been integrated into a more general theoretical frame accounting for contextual variation. In this paper the literature on aggression, agonism, affiliation, and social dominance is reviewed in light of behavioral ecological theory suggesting that different forms of competition (scramble and contest) determine, respectively, the use of affiliative and aggressive strategies. Results generally support the hypotheses advanced by this theory. In order to further integrate these findings suggestions for the study sequences of behavior, where reconciliations follow aggression, are made.
BACKGROUND:Cardiovascular disease is associated with epigenomic changes in the heart; however, the endogenous structure of cardiac myocyte chromatin has never been determined.
METHODS:To investigate ...the mechanisms of epigenomic function in the heart, genome-wide chromatin conformation capture (Hi-C) and DNA sequencing were performed in adult cardiac myocytes following development of pressure overload–induced hypertrophy. Mice with cardiac-specific deletion of CTCF (a ubiquitous chromatin structural protein) were generated to explore the role of this protein in chromatin structure and cardiac phenotype. Transcriptome analyses by RNA-seq were conducted as a functional readout of the epigenomic structural changes.
RESULTS:Depletion of CTCF was sufficient to induce heart failure in mice, and human patients with heart failure receiving mechanical unloading via left ventricular assist devices show increased CTCF abundance. Chromatin structural analyses revealed interactions within the cardiac myocyte genome at 5-kb resolution, enabling examination of intra- and interchromosomal events, and providing a resource for future cardiac epigenomic investigations. Pressure overload or CTCF depletion selectively altered boundary strength between topologically associating domains and A/B compartmentalization, measurements of genome accessibility. Heart failure involved decreased stability of chromatin interactions around disease-causing genes. In addition, pressure overload or CTCF depletion remodeled long-range interactions of cardiac enhancers, resulting in a significant decrease in local chromatin interactions around these functional elements.
CONCLUSIONS:These findings provide a high-resolution chromatin architecture resource for cardiac epigenomic investigations and demonstrate that global structural remodeling of chromatin underpins heart failure. The newly identified principles of endogenous chromatin structure have key implications for epigenetic therapy.
— The role of play in human development is a source of controversy. Some view it as indispensable to children’s healthy development and education, whereas others marginalize it as a topic unworthy of ...study and of questionable functional significance. This article suggests that differences in how researchers define play and conceptualize function have led to this disagreement. It also makes educational policy and research recommendations about the role of play in children’s lives.
Play in evolution and development Pellegrini, Anthony D.; Dupuis, Danielle; Smith, Peter K.
Developmental review,
06/2007, Letnik:
27, Številka:
2
Journal Article
Recenzirano
In this paper we examine the role of play in human ontogeny and phylogeny, following Surplus Resource Theory. We consider how juveniles use play to sample their environment in order to develop ...adaptive behaviors. We speculate about how innovative behaviors developed in play in response to environmental novelty may influence subsequent evolutionary processes. Play during this period of immaturity is especially important in the processes of development and evolution, because in play new strategies and behaviors can be developed with minimal costs and these strategies, in turn, can influence evolutionary processes. We posit that play influences these processes by supporting the development of new strategies in novel environments during the juvenile period.
The occurrence of bullying, victimization, and aggressive
victimization was documented in a sample of 5th graders. Bullies
comprised about 14% of the sample, whereas aggressive victims
and victims ...comprised, respectively, 5% and 18%.
Bullying and aggressive victimization was positively related to
youngsters' emotionality and activity and negatively related to peer
popularity. Although proactive and reactive aggression was related
to bullying scores within the group of bullies, only proactive
aggression was related to within-group popularity for bullies.
Having friends and being liked by one's peers were protective
factors against victimization, although the latter was more powerful
than the former. Suggestions for future research, school policy, and
intervention are made.
Evolutionary developmental psychology involves the expression of evolved, epigenetic programs, as described by the developmental systems approach, over the course of ontogeny. There have been ...different selection pressures on organisms at different times in ontogeny, and some characteristics of infants and children were selected in evolution to serve an adaptive function at that time in their life history rather than to prepare individuals for later adulthood. Examples of such adaptive functions of immaturity are provided from infancy, play, and cognitive development. Most evolved psychological mechanisms are proposed to be domain specific in nature and have been identified for various aspects of children's cognitive and social development, most notably for the acquisition of language and for theory of mind. Differences in the quality and quantity of parental investment affect children's development and influence their subsequent reproductive and childcare strategies. Some sex differences observed in childhood, particularly as expressed during play, are seen as antecedents and preparations for adult sex differences. Because evolved mechanisms were adaptive to ancestral environments, they are not always adaptive for contemporary people, and this mismatch of evolved mechanisms with modern environments is seen in children's maladjustment to some aspects of formal schooling. We argue that an evolutionary perspective can be valuable for developing a better understanding of human ontogeny in contemporary society and that a developmental perspective is important for a better understanding of evolutionary psychology.
The authors suggest that the recess period serves a positive purpose in the primary school curriculum, counter to the current practice of minimizing recess in many schools across North America and ...the United Kingdom. The authors' position is embedded in the larger debate about school accountability; they argue that school policy should be based on the best theory and empirical evidence available. They support their argument for the importance of recess with theory and with experimental and longitudinal data showing how recess breaks maximize children's cognitive performance and adjustment to school.
Originally published in 1998. This book presents a model of social-contextual influences on children’s literacy and literate language. Literate language is similar to the language teachers use and to ...the language used in reading books for young children. Based on a longitudinal study in homes and schools, the authors here present the results of how diverse and close social relationships influence children’s literacy learning as they progress through the first three years of formal schooling, and discuss implications for teaching practice. Different types of reading matter in the home are examined and it is suggested that peers are helpful to the learning of literacy. Rather than separate friends as often happens in the classroom, this book suggest that interaction should be encouraged. It will be of interest to researchers and students of developmental and educational psychology, and to anyone interested in early cognitive and social development.
1. Early Literacy: Background and Theory 2. Methods in the Study of Children’s Literacy Development at Home and at School 3. Joint Reading Between Parents and Children 4. Peer Interaction, Play, and Literate Language: Naturalistic and Experimental Evidence from Preschool and Primary School Classrooms 5. Social Networks at Home and School: Diverse Social Contacts as Affordances for Literacy Development 6. Role of Social Relationships in Literacy Development 7. Relationships, Individual Differences, and Children’s Use of Literate Language 8. A Case Study of School-based Literacy Learning 9. What is to be Done?
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