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981.
Phonological awareness, phonological memory, and phonological access to lexical storage play important roles in acquiring
literacy. We examined the convergent, discriminant, and predictive validity of these phonological processing abilities (PPA)
in 389 3-, 4-, and 5-year-old children. Confirmatory factor analysis supported the validity of each PPA as separate from general
cognitive ability and separate from each other. Multigroup structural equation modeling (SEM) with mean structure demonstrated
that older preschoolers have better developed latent PPA than younger preschoolers but that the structure of PPA is equivalent.
RAN was found uniquely associated with letter knowledge and text discrimination in younger preschoolers, and PA was found
uniquely associated with word reading skills in older preschoolers. Finally, general cognitive ability was only indirectly
associated with emergent literacy via PPA. These results highlight the importance of PPA in the early literacy development
of English-speaking preschool children. 相似文献
982.
The purpose of the present study was to explore the possibilities for the assessment of growth in phonological awareness of
children in kindergarten and first grade. Phonological awareness was measured using four sets of items involving rhyming,
phoneme identification, phoneme blending, and phoneme segmentation. The results of an exploratory factor analysis and analyses
conducted within the framework of item response theory showed one latent ability to underlie the different sets of items,
which nevertheless differed in difficulty. Analyses in terms of the children’s ability further showed the phonological awareness
measures to be sensitive to growth. The amount of information supplied by the different sets of items depended on the children’s
level of ability. The conclusion that it is possible to accurately monitor the development of children’s phonological awareness
in the early elementary grades appears to be justified, and this possibility opens up new perspectives for the early screening
for reading problems and dyslexia. 相似文献
983.
S M Srivastava 《Resonance》2007,12(2):59-70
In 1931, the great Austrian mathematician Kurt Gödel proved “all consistent axiomatic formulations of number theory include undecidable propositions”. This discovery of Gödel and its proof had enormous repercussions in mathematics and computer science. The proof hinged upon the writing of a self-referential mathematical statement, in the same way as the liar’s paradox — I am lying — is a self-referential statement. In this three-part article, we describe Gödel’s discovery and his famous proof. 相似文献
984.
985.
OBJECTIVE: Children's Advocacy Centers (CACs) aim to improve child forensic interviewing following allegations of child abuse by coordinating multiple investigations, providing child-friendly interviewing locations, and limiting redundant interviewing. This analysis presents one of the first rigorous evaluations of CACs' implementation of these methods. METHODS: This analysis is part of a quasi-experimental study, the Multi-Site Evaluation of Children's Advocacy Centers, which evaluated four CACs relative to within-state non-CAC comparison communities. Case abstractors collected data on investigation methods in 1,069 child sexual abuse cases with forensic interviews by reviewing case records from multiple agencies. RESULTS: CAC cases were more likely than comparison cases to feature police involvement in CPS cases (41% vs. 15%), multidisciplinary team (MDT) interviews (28% vs. 6%), case reviews (56% vs. 7%), joint police/child protective services (CPS) investigations (81% vs. 52%) and video/audiotaping of interviews (52% vs. 17%, all these comparisons p<.001). CACs varied in which coordination methods they used, and some comparison communities also used certain coordination methods more than the CAC with which they were paired. Eighty-five percent of CAC interviews took place in child-friendly CAC facilities, while notable proportions of comparison interviews took place at CPS offices (22%), police facilities (18%), home (16%), or school (19%). Ninety-five percent of children had no more than two forensic interviews, and CAC and comparison differences on number of interviews were mostly non-significant. CONCLUSIONS: Relative to the comparison communities, these CACs appear to have increased coordination on investigations and child forensic interviewing. The CAC setting was the location for the vast majority of CAC child interviews, while comparison communities often used settings that many consider undesirable. CACs showed no advantage on reducing the number of forensic interviews, which was consistently small across the sample. 相似文献
986.
Jean-Pierre V. M. Hérubel 《Learned Publishing》2023,36(2):164-170
Academic book and journal publishing constitutes the majority focus of university presses. Besides commercial scholarly publishers, academic scholars and researchers view the opportunities provided by university presses as important venues for the dissemination of their research. This discussion focuses on the disciplinary imperative to publish scholarship that is ever more fluid and specialized as academic disciplines continue to become further nuanced in their response to the increasing knowledge produced by humanities and social science inquiry. The focus is on university presses and not commercial scholarly presses, although constitute a significant locus of scholarly publishing. What are the general characteristics of academic specialization and university press publishing? Further, how is disciplinary fluidity, especially evolving specialization, reflected in university press book publishing nomenclature and how scholarship is tied to the intellectual preoccupations of academic specialization? Multi- and inter-disciplinarities further articulate disciplinary publishing, accelerating disciplinary fluidity. Examples from disciplinary and emerging configurations of disciplinary nomenclature utilized by university presses offers insight into specialization and publishing. Academic history publishing is used to illustrate newly emerging fluid disciplinary configurations. 相似文献
987.
In this paper, a novel reconstruction technique based on level set method and algebraic reconstruction technique is proposed for multiphase flow computed tomography (CT) system. The curvature-driven noise reduction method is inserted into the conventional iteration procedure of algebraic reconstruction technique to improve the image quality and convergence speed with limited projection data. By evolving the image as a set of iso-intensity contours after each updation, the sufficient number of iterations for acceptable results is reduced by 80%-90%, while the image quality is enhanced obviously. Quantitative evaluation of image quality is given by using both relative image error and correlation coefficient. The resultant images can be utilized to detect flow regimes for monitoring industrial multiphase flow. Laboratory results demonstrate the feasibility of the proposed method. Phantoms of four typical flow regimes can be reconstructed from few-view projection data efficiently, and the corresponding image errors and correlation coefficients are acceptable for the cases tested in this paper. 相似文献
988.
Considering the uncertainty of material performance, geometric characteristic and analysis method, the analysis of statistical parameters of the resistance of cast ball-and-socket support joints and the reliability analysis are carried out by JC method (improved first-order second-moment method) based on the relevant experimental data. Results show that the resistance partial factor of the joint increases with the increase of the reliability index. The resistance partial factors are suggested corresponding to the reliability index under different load combinations. Moreover, the suggested resistance partial factor is adopted in reliability design, and it is found that the reliability index of the joint is larger than the target reliability index. The optimal load combination is the one in which live load plays an important control role. Finally, based on the suggested resistance partial factors, the reliability analysis of cast ball-and-socket support joints of a project is conducted. 相似文献
989.
Amanda Harrison Megan Phelps Arany Nerminathan Shirley Alexander Karen M. Scott 《British journal of educational technology : journal of the Council for Educational Technology》2019,50(2):531-545
University policies prohibiting use of mobile devices by medical students during clinical placements are contradicted by regular use by physicians. Consequently, many students use their mobile devices, which can be beneficial for learning but may put patient privacy at risk. This study explores the reasons underlying students' decisions about using mobile devices in clinical settings. We used a mixed-methods sequential explanatory design involving a questionnaire and focus groups. Qualitative data from the questionnaire and focus groups was analysed through thematic analysis. We found students were aware of the risks mobile devices posed to professionalism and medical practice. Despite prohibitions, many made individual decisions to use mobile devices because the benefits outweighed the risks. These students were influenced by an organised, strategic approach to learning and a motivation to comply with the beliefs and behaviours of their medical teams and conform to physicians' directives in order to participate in their community of practice. Many students appear to be transferring everyday use of mobile devices to clinical settings. There is a need to understand and promote aspects of learning that are enhanced by mobile devices in clinical settings, while articulating clear guidelines and boundaries compatible with the professional behaviour expected of students. 相似文献
990.
Youngmin Park Ying Xu Penelope Collins George Farkas Mark Warschauer 《British journal of educational technology : journal of the Council for Educational Technology》2019,50(4):1896-1912
The current study examines the effects of digital scaffolding on the English literacy of fourth- and sixth-grade students. A total of 1085 native English-speaking and language minority students from 25 treatment classes and 20 control classes across three school districts participated in this study for one school year. Treatment students read their English language arts and social studies text in visual-syntactic text format (VSTF) on their laptops and control students read the regular block format of the textbook either on their laptops or in print. Observations and interviews revealed that VSTF reading facilitated instruction processes and student learning in reading activities. The results of California Standard Tests (CST) before and after the treatment revealed that sixth-graders who received syntactic scaffolding outperformed control students on the composite CST score. In particular, reading in VSTF benefited the treatment students in three CST sub-categories: word analysis, written conventions and writing strategies. This study suggests that future research should investigate instructional strategies that support reading and writing development of adolescents, including at-risk students, using syntactic scaffolding. 相似文献