406 research outputs found
Tree transducers and tree languages
Tree transducers (automata which read finite labeled trees and output finite labeled trees) are used to define a hierarchy of families of âtree languagesâ (sets of trees). In this hierarchy, families generated by âtop-downâ tree transducers (which read trees from the root toward the leaves) alternate with families generated by âbottom-upâ tree transducers (which read trees from the leaves toward the root). A hierarchy of families of string languages is obtained from the first hierarchy by the âyieldâ operation (concatenating the labels of the leaves of the trees). Both hierarchies are conjectured to be infinite, and some results are presented concerning this conjecture. A study is made of the closure properties of the top-down and bottom-up families in the hierarchies under various tree and string operations. The families are shown to be closed under certain operations if and only if the hierarchies are finite
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Early Literacy: An Examination of the Principal Behaviors That Impact Reading Achievement
Literacy is fundamental to formal education, learning, and training for future career related skills. It provides not only the means of acquisition of information and skills during schooling, but it is a vital predictor of a person's general level of education in school as well as successful completion of schooling. Literacy skills serve as the major foundational skill for all school-based learning and without it, chances for academic and occupational success are limited. Despite the efforts of teachers, a significant portion of students continue to fail to achieve success in early literacy in school, with severe consequences for their subsequent educational progress, career opportunities and life chances. The extent of this problem varies throughout school systems. All of our children are affected by their reading ability, and as educators it is critical to provide for all students the most effective literacy programs and strategies which are research based, data-driven and successfully replicated. Because of the psychological, social and economic consequences of reading failure, it is critical to review the research to determine the risk factors that may predispose youngsters to reading failure, and the instructional practices that can be applied to ameliorate reading deficits at the earliest possible time. The failure to achieve in literacy is a fact, which continues to carry dire social and economic consequences for the children, as well as for this society. Furthermore, there is a substantial body of research indicating that schools have a narrow window of opportunity to make a difference. Students who fail to make progress in literacy during the first two years of school rarely catch up with their peers and are at-risk of becoming low achievers who are alienated from school and who dropout of education at the earliest opportunity. On the other hand, impressive empirical evidence is now available to support the notion that failure to make progress in literacy is preventable for all except a very small portion of children. This study reviews the relationship between the principal's knowledge of early literacy and student achievement in reading by the third grade. It will also describe the causal factors that may predispose young children to reading difficulties, as well as the instructional programs and teacher strategies that can be implemented to ameliorate the difficulties. Quantitative and qualitative methodologies are used to analyze the data. Narratives, tables and figures are used to further enhance the research
Understanding Mothers of Late Preterm Infants
The experience of becoming a mother is a personal and social experience influenced by individual characteristics, friends and family, and the infant. The journey to become a mother encompasses concepts of maternal competence and responsiveness. The purpose of this study was to examine maternal competence and responsiveness to the infant in mothers of late preterm infants compared to mothers of full term infants. The conceptual model for this work was based on the work of Reva Rubin describing maternal identity and role development. Maternal competence and responsiveness are components of maternal role and are influenced by social support, maternal self-esteem, well-being, stress and mood. In addition, infant temperament and perception of infant vulnerability influence development of maternal competence and responsiveness. A non-experimental repeated measures design was used to compare maternal competence and responsiveness in two groups of postpartum mothers. One group consisted of mothers of late preterm infants 34-36, 6/7 weeks gestation. The second group consisted of mothers of term infants, \u3e/=37 weeks gestation. Both primiparas and multiparas were included in the study. Data was collected in the initial postpartum period prior to discharge from the hospital and again at six-weeks postpartum. No statistically significant differences in development of maternal competence or responsiveness between mothers of LPIs and term infants were identified. This study adds to our knowledge concerning outcomes of mothers of late preterm infants and development of competence and responsiveness
Honeybee Associative Learning Performance and Metabolic Stress Resilience Are Positively Associated
Background: Social-environmental influences can affect animal cognition and health. Also, human socio-economic status is a covariate factor connecting psychometric test-performance (a measure of cognitive ability), educational achievement, lifetime health, and survival. The complimentary hypothesis, that mechanisms in physiology can explain some covariance between the same traits, is disputed. Possible mechanisms involve metabolic biology affecting integrity and stability of physiological systems during development and ageing. Knowledge of these relationships is incomplete, and underlying processes are challenging to reveal in people. Model animals, however, can provide insights into connections between metabolic biology and physiological stability that may aid efforts to reduce human health and longevity disparities. Results: We document a positive correlation between a measure of associative learning performance and the metabolic stress resilience of honeybees. This relationship is independent of social factors, and may provide basic insights into how central nervous system (CNS) function and metabolic biology can be associated. Controlling for social environment, age, and learning motivation in each bee, we establish that learning in Pavlovian conditioning to an odour is positively correlated with individual survival time in hyperoxia. Hyperoxia induces oxidative metabolic damage, and provides a measure of metabolic stress resistance that is often related to overall lifespan in laboratory animals. The positive relationship between Pavlovian learning ability and stress resilience in the bee is not equally established in other model organisms so far
Lower Bounds for On-Line Two-Dimensional Packing Algorithms
Coordinated Science Laboratory was formerly known as Control Systems LaboratoryJoint Services Electronics Program / DAAG-29-78-C-001
Liver regeneration after living donor transplantation: Adultâtoâadult living donor liver transplantation cohort study
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/109827/1/lt23966.pd
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