Cytocompatible cellulose nanofibers from invasive plant species Agave americana L. and Ricinus communis L.: a renewable green source of highly crystalline nanocellulose     

Evdokimova  Olga L.  Alves  Carla S.  Krsmanović Whiffen  Radenka M.  Ortega  Zaida  Tomás  Helena  Rodrigues  João 《Journal of Zhejiang University. Science. B》2021,22(6):450-461

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   

An exploratory study on the emergency remote education experience of higher education students and teachers during the COVID-19 pandemic     

Gabriella Oliveira  Jorge Grenha Teixeira  Ana Torres  Carla Morais 《British journal of educational technology : journal of the Council for Educational Technology》2021,52(4):1357-1376

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Book review     

Sibylle Hielscher  Elaine Rivers  Gerhard Mittelstädt  Alexander N. Charters  T. Neville Postlethwaite 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》1993,39(5):443-452

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Matthew effects in writing productivity during second grade     

Wood  Carla  Schatschneider  Christopher  Wanzek  Jeanne 《Reading and writing》2020,33(6):1377-1398

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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Young adolescent psychological need profiles: Associations with classroom achievement and well‐being     

Stephen R. Earl  Ian M. Taylor  Carla Meijen  Louis Passfield 《Psychology in the schools》2019,56(6):1004-1022

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 (F_4,540 = 7.03; p < 0.001; η_p² = 0.05), well‐being (F_8,1,136 = 45.63; p < 0.001; Wilk's Λ = 0.57; η_p² = 0.24) and lowest ill‐being (F_8,1,134 = 23.39; p < 0.001; Wilk's Λ = 0.74, η_p² = 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   

Bookreviews     

Gilbert de Landsheere  Marten Groen  John Biggs  John F. Willatt  David Thomas  Clare Burstall  Robin Russell  J. R. Barr  Gerhard Pause  Donald E. Super  John B. Biggs  Alan C. Purves  Klaus Schleicher  Herbert A. Thelen  Neville Postlethwaite  Börje Holmberg  Kenneth Austwick  Sven Hilding  A Group of Scottish Physics Teachers 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》1967,13(1):90-123

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Scaffolding reflection and articulation of scientific explanations in a data-rich,project-based learning environment: An investigation of progress portfolio     

Susan M. Land  Carla Zembal-Saul 《Educational technology research and development : ETR & D》2003,51(4):65-84

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   

A Twin Study of Attachment in Preschool Children   总被引：3，自引：0，他引：3  

Thomas G. O''Connor  & Carla M. Croft 《Child development》2001,72(5):1501-1511

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   

Key actors’ involvement in implementing assessment reforms and using quality improvement measures     

Guri Skedsmo  Stephan Gerhard Huber 《Educational Assessment, Evaluation and Accountability》2018,30(2):93-95

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Cognitive Teaching Methods for Special Education: Development of Approaches for Intervention and Assessment in Germany     

Gerhard W. Lauth  Karl H. Wiedl 《International Journal of Disability, Development & Education》1989,36(3):187-202

FOLLOWING a short introduction to historical aspects of the development of cognitive teaching methods, four current areas of research are described: cognitive behaviour modification with a focus on problem solving and metacognitive abilities, comprising the methods of cognitive modelling and self‐instruction; intelligence training based on the theoretical propositions of inductive thinking; attempts at applying Piagetian concepts as a conceptual framework for education and training; dynamic testing, focussing on modifiability of performance and thus bridging the gap between diagnostic assessment and education. Basic theoretical assumptions, methods and applications are separately discussed for each of these fields. Empirical data are presented for evaluation of their level of development Summarizing the results, it seems, that promising effects of training and fruitful application of diagnostic procedures can be obtained; however, implementation of the respective methods in special education settings does not show great progress. It is, thus, concluded that research on implementation is indispensable.  相似文献