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91.
92.
The extraordinary romance and thrilling adventure associated with the tale of wootz steel shows how Indian metallurgists were
the world leaders in antiquity in the manufacture of this legendary high-grade steel. In many ways this material was brought
to global attention by the writings of Cyril Stanley Smith. Modern metallurgy and materials science rest on the foundation
built by the study of this steel during the past three centuries. 相似文献
93.
Pedro Gutiérrez Bueno wrote two editions of a chemistry textbook between 1788 and 1802. The paper offers a comparative view
of both editions taking into account Gutiérrez Bueno’s biography, his intended audience and the changes related to the so-called
chemical revolution. Some conclusions are at odds with common images about scientific revolutions and the role of textbooks
in science. The analysis aims to shed some light on the multiple historical forces shaping textbooks and the way in which
scientific change is assimilated by their writers.
This research was partially supported by the program BHA2002-04611-CO3-02 相似文献
94.
Effectiveness of Spanish intervention for first-grade English language learners at risk for reading difficulties 总被引:1,自引:0,他引:1
Vaughn S Linan-Thompson S Mathes PG Cirino PT Carlson CD Pollard-Durodola SD Cardenas-Hagan E Francis DJ 《Journal of learning disabilities》2006,39(1):56-73
The effectiveness of an explicit, systematic reading intervention for first-grade students whose home language was Spanish and who were at risk for reading difficulties was examined. Participants were 69 students in 20 classrooms in 7 schools from 3 districts who initially did not pass the screening in Spanish and were randomly assigned within schools to a treatment or comparison group; after 7 months, 64 students remained in the study. The intervention matched the language of instruction of their core reading program (Spanish). Treatment groups of 3 to 5 students met daily for 50 min and were provided systematic and explicit instruction in oral language and reading by trained bilingual intervention teachers. Comparison students received the school's standard intervention for struggling readers. Observations during core reading instruction provided information about the reading instruction and language use of the teachers. There were no differences between the treatment and comparison groups in either Spanish or English on any measures at pretest, but there were significant posttest differences in favor of the treatment group for the following outcomes in Spanish: Letter-Sound Identification (d = 0.72), Phonological Awareness composite (d = 0.73), Woodcock Language Proficiency Battery-Revised Oral Language composite (d = 0.35), Word Attack (d = 0.85), Passage Comprehension (d = 0.55), and two measures of reading fluency (d = 0.58-0.75). 相似文献
95.
Students learning to read in more than one language are a growing population in schools. Early screening and identification of reading difficulties may lead to better outcomes for all students. Oral reading fluency (ORF) is one tool shown to be both a reliable measure of reading and an accurate method to identify students at risk for poor reading outcomes. This study synthesized available validity evidence for ORF with biliterates. All included studies (n = 31) were conducted with English language learners in grades K–8. Results suggested that although ORF is correlated with reading outcomes, the accuracy of ORF to identify English learners at risk of poor reading outcomes does not meet criteria. The strength of validity evidence differed by language proficiency of participants. Finally, the quality of the reviewed studies was low in critical areas. 相似文献
96.
97.
Meagan R. Talbott Gregory S. Young Jeff Munson Annette Estes Laurie A. Vismara Sally J. Rogers 《Child development》2020,91(3):743-753
In typical development, gestures precede and predict language development. This study examines the developmental sequence of expressive communication and relations between specific gestural and language milestones in toddlers with autism spectrum disorder (ASD), who demonstrate marked difficulty with gesture production and language. Communication skills across five stages (gestures, word approximations, first words, gesture-word combinations, and two-word combinations) were assessed monthly by blind raters for toddlers with ASD participating in an randomized control trial of parent-mediated treatment (N = 42, 12–30 months). Findings revealed that toddlers acquired skills following a reliable (vs. idiosyncratic) sequence and the majority of toddlers combined gestures with words before combining words in speech, but in contrast to the pattern observed in typical development, a significant subset acquired pointing after first words. 相似文献
98.
This study utilized data from the Avon Longitudinal Study of Parents and Children (N = 14,860) to examine whether early-life family income (age 0–5) predicted long-term academic achievement (age 16–18) and to investigate the role of executive function (EF) assessed multiple times across age 7–11 in explaining this association. Task-based EF was a significant mediator between early-life family income and later academic achievement in every model. This mediating pathway persisted when adjusting for a comprehensive panel of covariates including verbal IQ, sex, family income at ages 8 and 18, and early-life temperament. Additionally, teacher-rated and parent-rated EF mediated in some models. Overall, these findings suggest that childhood EF may play an important role in perpetuating income-based educational disparities. 相似文献
99.
Research in Higher Education - Increasingly, undergraduates take more than 4 years to complete a baccalaureate, a situation widely perceived as a waste of time and money, for students,... 相似文献
100.
Paul Horton Camilla Forsberg 《Educational research; a review for teachers and all concerned with progress in education》2020,62(1):95-110
ABSTRACTBackground Research suggests that negative peer interactions that compromise student safety and wellbeing often occur in spaces at school that are not easily visible, not adequately monitored, overcrowded and/or relatively unstructured. In a large online survey conducted in Swedish schools by the anti-bullying organisation, Friends, a small proportion of students indicated that they felt unsafe in the school canteen and responded to a question about why they felt unsafe there. As the canteen is often reported to be a space where negative peer interactions, such as harassment, bullying and other forms of school violence, occur, but little is known about why negative peer interactions occur there, we were particularly interested in exploring why some students perceived their school canteen to be an unsafe space.Purpose Taking a social-ecological perspective, our aim was to investigate why students reported feeling unsafe in the environment of the school canteen.Method In order to investigate this question, we analysed 1,547 responses from students in Swedish schools in grades 3–6 (ages 9–12). The responses were from the anti-bullying organisation Friends’ online questionnaires from 2011 to 2016. In the responses, students who indicated that they felt unsafe in the school canteen explained why they felt this way. Data were analysed qualitatively, using a six-step thematic approach.Findings The analysis identified four key themes: Space constraints, Time restrictions, The risk of social blunders and The negative actions of others. We discuss the findings in terms of the macrosystem, exosystem, mesosystem and microsystem.Conclusions In matters of student safety and wellbeing, we argue that it is not only important to consider the social context, but also how that context is interconnected with environmental and structural elements. 相似文献