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21.
Enactment of federal educational policy has direct implications for states and local school districts across the nation, particularly in the areas of accountability and funding. This study utilized constructivist grounded theory to examine the impact of policy on science education reform in a large, urban school district over a 5-year period. The existence and interaction between macro and micro, and explicit and implicit policies created educational turbulence. Findings further extend upon Fullan’s (Change theory: a force for school improvement, 2006) change theory adding high-stakes accountability as a prevalent distractor issue and the need for quad-level, rather than tri-level engagement in reform. Suggestions for addressing educational turbulence are provided.  相似文献   
22.
Consultation is a promising approach to creating change in early childhood programs, from innovations in instructional strategies to the enhancement of global program quality. Studies of consultation effectiveness have been hampered by limited reports of implementation fidelity related to consultation procedures. This article describes the challenges of supporting and measuring implementation fidelity in a 5-state study in which community consultants followed a collaborative consultation model to enhance global quality in childcare programs. The authors consider the limitations of using a randomized experimental design to study the effectiveness of consultation and share lessons learned in their efforts to enhance treatment fidelity without compromising the basic tenets of the model or the rigorous design.  相似文献   
23.
SYNOPSIS

Objective . To explore whether maternal sensitivity is associated with Autism Spectrum Disorder (ASD) severity in children with and without ASD. Design . The samples consisted of 25 Mexican dyads of children with ASD (aged 3.1-6.9 years) and their mothers (aged 20-47 years) and 24 Mexican dyads of children without ASD (aged 3.4-6.7 years) and their mothers (aged 24-45 years). Maternal sensitivity and ASD severity symptoms were scored from 2-h videos of mother-child daily interactions. Results . A between-group comparison showed a trend toward less severe ASD in children with highly sensitive mothers, specifically in the Nonverbal Communication subdomain. Conclusions . Greater maternal sensitivity is associated with improved social ability in children with ASD.  相似文献   
24.
In this study, the fibers of invasive species Agave americana L. and Ricinus communis L. were successfully used for the first time as new sources to produce cytocompatible and highly crystalline cellulose nanofibers. Cellulose nanofibers were obtained by two methods, based on either alkaline or acid hydrolysis. The morphology, chemical composition, and crystallinity of the obtained materials were characterized by scanning electron microscopy(SEM) together with energy-dispersive X-ray spectroscopy(EDX), dynamic light scattering(DLS), X-ray diffraction(XRD), and Fourier transform infrared(FTIR)spectroscopy. The crystallinity indexes(CIs) of the cellulose nanofibers extracted from A. americana and R. communis were very high(94.1% and 92.7%, respectively). Biological studies evaluating the cytotoxic effects of the prepared cellulose nanofibers on human embryonic kidney 293 T(HEK293 T) cells were also performed. The nanofibers obtained using the two different extraction methods were all shown to be cytocompatible in the concentration range assayed(i.e., 0-500 μg/mL). Our results showed that the nanocellulose extracted from A. americana and R. communis fibers has high potential as a new renewable green source of highly crystalline cellulose-based cytocompatible nanomaterials for biomedical applications.  相似文献   
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26.

The primary aims of this study were twofold: (a) to describe average change in the written narrative performance of second grade students from the fall and spring of the school year and (b) examine patterns of individual growth to test for Matthew effects. Participants included 299 children in second grade. Microstructural measures were derived from students’ written narratives including: number of different words (NDW), total number of words (TNW), and accuracy of spelling and grammar. Significant increases in NDW, TNW, and spelling accuracy were evidenced from fall to spring. Students averaged 55 total words in the fall and averaged 69 words in the spring, with a statistically significant increase of 14 words t(299)?=?8.4, p?<?.0001). The variance in TNW from fall to spring increased from Var?=?791 to Var?=?1005, which was a significant increase and the correlation of initial Fall TNW and growth in TNW was also significant (r?=?0.39). Additionally, results from a two-level hierarchical linear model with students nested within teachers indicated that initial level of TNW predicted the change in TNW from fall to spring, with higher levels of initial TNW being related to larger gains in TNW. Significant predictors of Matthew effects included teacher or classroom and free/reduced lunch eligibility. Written personal narrative measures are sensitive to developmental change across a school year. Evidence of Matthew effects in lexical productivity suggests additional support may be warranted to ameliorate gaps in writing achievement.

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27.
Drawing on self‐determination theory, a person‐centered methodology was adopted to identify distinct pupil profiles based on their psychological need satisfaction. A sample of 586 pupils (387 male, 199 female; mean age = 12.6, range 11–15 years old) from three secondary schools reported their psychological need satisfaction, and well‐ and ill‐being, with teachers rating pupil achievement. Hierarchical cluster analysis revealed five distinct profiles. Four profiles indicated synergy existed between the three needs, showing similar in‐group levels of satisfaction across the needs but in varying amounts. Univariate and multivariate analyses, controlling for school and taught subject, revealed the satisfied group displayed the highest classroom performance (F4,540 = 7.03; p < 0.001; ηp2 = 0.05), well‐being (F8,1,136 = 45.63; p < 0.001; Wilk's Λ = 0.57; ηp2 = 0.24) and lowest ill‐being (F8,1,134 = 23.39; p < 0.001; Wilk's Λ = 0.74, ηp2 = 0.14), whereas the dissatisfied group displayed the most adverse outcomes. The findings illustrate that the three psychological needs may operate interdependently and should be considered in combination rather than in isolation. The research offers practical insights into why pupils may function differently in classrooms and could inform targeted initiatives towards pupils with psychological need satisfaction deficits.  相似文献   
28.
In this study, we examined how learners developed scientific explanations about light with the assistance of various technology-based scaffolds. The study emphasis was on scaffolding processes of reflection and articulation. We used a content-neutral software program (Progress Portfolio) to create the instructional scaffolds. A qualitative research design was used to investigate two pairs of prospective teachers in a science content course in engineering. Our findings suggested that the computer-based scaffolds used in our study were useful to support articulation, reflection, and revision of explanations, when certain conditions were met. A major theme of our findings relates to interacting effects among learner characteristics, teacher coaching, software scaffolding design, and task characteristics. This material is based on work supported by the National Science Foundation under NSF REC 9980055, which was granted to the second author. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the National Science Foundation. The authors would like to acknowledge Joe Taylor for his role in the design and implementation of the study.  相似文献   
29.
A Twin Study of Attachment in Preschool Children   总被引:3,自引:0,他引:3  
The degree to which individual differences in child-parent attachment were mediated by genetic, shared environmental, and nonshared environmental influences was investigated. One hundred and ten preschool-aged twin pairs (N = 220) were assessed in the Strange Situation and coded using conventional four-way classifications and a continuous measure of attachment security. The degree of sibling similarity in attachment was substantial, with an overall concordance rate of 67% at the secure/insecure level. The degree of concordance was equally high in monozygotic and dizygotic twin pairs, 70% and 64%, respectively, suggesting little genetic influence but a moderate degree of discordance. Twin similarity on the continuous measure of attachment security was r(57) = .48 and r(53) = .38 for monozygotic and dizygotic twin pairs, respectively, also consistent with a modest role for genetic influence but a significant effect for shared and nonshared environment. The implications for genetic influences on the environment and for understanding nonshared and shared environmental influences are discussed.  相似文献   
30.
In four conditioned suppression experiments with rats (Rattus norvegicus), backward pairings of a shock unconditioned stimulus (US) and a tone conditioned stimulus (CS) eliminated an already established conditioned response (CR), but there was recovery of the CR if the shock was later withheld. In Experiment 1, there was recovery after backward pairings, regardless of whether the period after the US was normally shock free or not. In Experiment 2, the occurrence of recovery depended on the CS’s being presented closely after the US in response elimination. Levels of recovery were positively correlated with the resistance of the response to elimination during backward pairings (Experiments 3 and 4). Taken together, these data support the notion that recovery after backward pairings is a form of renewal (see, e.g., Bouton, 1991) and is not due toprotection from extinction.  相似文献   
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