Audiogenic seizures in mice: Asymmetries of the preconvulsive running pattern and subsequent seizure

Asymmetries in the progression of unilaterally and bilaterally induced audiogenic seizures were examined in DBA/2J and SJL/J mice. Both strains were found to exhibit consistent asymmetries in direction(s) of running as well as in the side of fall during a convulsion. This correspondence suggests that the bursts of running are an integral part of an audiogenic seizure. The incorporation of information on asymmetries of the locomotor prelude in future studies should prove valuable for understanding the physiological mechanisms of audiogenic seizure.     

A longitudinal study of attitudes of students and parents coincident with court-ordered school desegregation

Attitudinal data were collected for a sample of 492 parents and public school children before implementation of a metropolitan desegregation plan and for 2 years after implementation. The variables measured included racial attitudes, feelings out desegregation, and school-related attitudes. There were small but significant changes on 7 of the 11 measures, with most of the changes occurring during the first year. There were race and grade-level differences on some of the variables before desegregation, but race and grade level were generally not related to changes over time.This research has been supported by a grant from the Rockefeller Foundation, Division of Social Sciences.     

Working and Playing Together: Prediction of Preschool Social-Emotional Competence from Mother-Child Interaction

The impact of mother-child interaction on preschoolers' social-emotional competence was evaluated. Twenty-five girls and 23 boys (mean age = 44 mos) and their mothers were videotaped performing four play/teaching tasks. Preschool teachers completed the Baumrind Preschool Behavior Q-Sort and the Behar Problem Behavior Questionnaire. Mother-child interaction aggregates represented task orientation, positive emotion, and allowance of autonomy/reliance on mother. Results indicated that specific maternal interaction aggregates coherently predicted the children's Positive Social Behavior, Assertiveness, and Sadness in the preschool setting. Child aggregates were less effective predictors of teachers' ratings. Several gender differences in the prediction of social-emotional competence were found (e.g., maternal allowance of autonomy predicted girls' sadness, but boys' sadness was predicted by their own negative emotion). These findings' contributions to the parent-child literature are discussed.     

Play as the Leading Activity of the Preschool Period: Insights from Vygotsky, Leont'ev, and Bakhtin

Cultural-historical psychology identifies play as the leading activity in preschool development. Vygotsky's (1967, 1978) seminal work outlined two categories of leading influences: play makes a foundational contribution to the development of semiotic mediation, and it involves active appropriation of social roles and rules and other integral aspects of social organization. Leont'ev's (1981) concept of appropriation and Bakhtin's (1981) concepts of heteroglossia and ideological becoming are used to elaborate and extend Vygotsky's original work, particularly with regard to creativity in preschool play. The paper concludes with a consideration of the pedagogical implications of the cultural-historical view on play, including the use of play to cultivate understanding of the arbitrary nature of signs and the appropriation of the social roles and organizational patterns of society.     

Science literacy and academic identity formulation

The purpose of this article is to report findings from an ethnographic study that focused on the co‐development of science literacy and academic identity formulation within a third‐grade classroom. Our theoretical framework draws from sociocultural theory and studies of scientific literacy. Through analysis of classroom discourse, we identified opportunities afforded students to learn specific scientific knowledge and practices during a series of science investigations. The results of this study suggest that the collective practice of the scientific conversations and activities that took place within this classroom enabled students to engage in the construction of communal science knowledge through multiple textual forms. By examining the ways in which students contributed to the construction of scientific understanding, and then by examining their performances within and across events, we present evidence of the co‐development of students' academic identities and scientific literacy. Students' communication and participation in science during the investigations enabled them to learn the structure of the discipline by identifying and engaging in scientific activities. The intersection of academic identities with the development of scientific literacy provides a basis for considering specific ways to achieve scientific literacy for all students. © 2004 Wiley Periodicals, Inc. J Res Sci Teach 41: 1111–1144, 2004     

Browsing mixed structured and unstructured data

Both structured and unstructured data, as well as structured data representing several different types of tuples, may be integrated into a single list for browsing or retrieval. Data may be arranged in the Gray code order of the features and metadata, producing optimal ordering for browsing. We provide several metrics for evaluating the performance of systems supporting browsing, given some constraints. Metadata and indexing terms are used for sorting keys and attributes for structured data, as well as for semi-structured or unstructured documents, images, media, etc. Economic and information theoretic models are suggested that enable the ordering to adapt to user preferences. Different relational structures and unstructured data may be integrated into a single, optimal ordering for browsing or for displaying tables in digital libraries, database management systems, or information retrieval systems. Adaptive displays of data are discussed.     

Teachers' education, classroom quality, and young children's academic skills: results from seven studies of preschool programs

In an effort to provide high-quality preschool education, policymakers are increasingly requiring public preschool teachers to have at least a Bachelor's degree, preferably in early childhood education. Seven major studies of early care and education were used to predict classroom quality and children's academic outcomes from the educational attainment and major of teachers of 4-year-olds. The findings indicate largely null or contradictory associations, indicating that policies focused solely on increasing teachers' education will not suffice for improving classroom quality or maximizing children's academic gains. Instead, raising the effectiveness of early childhood education likely will require a broad range of professional development activities and supports targeted toward teachers' interactions with children.