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131.
The purpose of this study was to investigate the differences among schools using student responses in the Trends in Mathematics and Science Study–1999 (TIMSS‐99) data. Schools were classified into two groups based on eighth grade students' overall achievement in science. Two different discriminant function analyses were performed to distinguish high‐ and low‐performing schools, based both on classroom practices and factor structures (student‐centered activities, teacher‐centered activities, attitudes toward technology use, socioeconomic status [SES], and doing well in science). The results indicate that there were significant differences between the two classifications of schools on ten variables regarding classroom practices and activities, and 29 variables regarding classroom practices, attitudes toward science, use of the computer and overhead projector (OHP), parental background characteristics, and need to do well in science. Contrary to general expectations, technology use (computer, OHP, etc.) was found to be negatively related to science achievement. Teachers should be trained on how to use technology in their classrooms. Turkey recently revised its curriculum to a student‐centered approach and this might increase students' ability to transfer knowledge into real life. Teachers and schools should pay more attention to SES effects. Teachers should also work toward building students' confidence in science. © 2007 Wiley Periodicals, Inc. J Res Sci Teach 44: 1417–1435, 2007 相似文献
132.
The aim of this study was to examine the effects of muscle-tendon length on joint moment and power during maximal sprint starts. Nine male sprinters performed maximal sprint starts from the blocks that were adjusted either to 40 degrees or 65 degrees to the horizontal. Ground reaction forces were recorded at 833 Hz using a force platform and kinematic data were recorded at 200 Hz with a film camera. Joint moments and powers were analysed using kinematic and kinetic data. Muscle - tendon lengths of the medial gastrocnemius, soleus, vastus medialis, rectus femoris and biceps femoris were calculated from the set position to the end of the first single leg contact. The results indicated that block velocity (the horizontal velocity of centre of mass at the end of the block phase) was greater (P < 0.01) in the 40 degrees than in the 65 degrees block angle condition (3.39 +/- 0.23 vs. 3.30 +/- 0.21 m . s(-1)). Similarly, the initial lengths of the gastrocnemius and soleus of the front leg in the block at the beginning of force production until half way through the block phase were longer (P < 0.001) in the 40 degrees than in the 65 degrees block angle condition. The initial length and the length in the middle of the block phase were also longer in the 40 degrees than in the 65 degrees block angle condition both for both the gastrocnemius (P < 0.01) and soleus (P < 0.01-0.05) of the rear leg. In contrast, the initial lengths of the rectus femoris and vastus medialis of the front leg were longer (P < 0.05) in the 65 degrees than in the 40 degrees block angle condition. All differences gradually disappeared during the later block phase. The peak ankle joint moment (P < 0.01) and power (P < 0.05) during the block phase were greater in the 40 degrees than in the 65 degrees block angle condition for the rear leg. The peak ankle joint moment during the block phase was greater (P < 0.05) in the 40 degrees block angle for the front leg, whereas the peak knee joint moment of the rear leg was greater (P < 0.01) in the 65 degrees block angle condition. The results suggest that the longer initial muscle-tendon lengths of the gastrocnemius and soleus in the block phase at the beginning of force production contribute to the greater peak ankle joint moment and power and consequently the greater block velocity during the sprint start. 相似文献
133.
C. Albrecht A. Hanssen-Doose K. Bös L. Schlenker S. Schmidt M. Wagner N. Will A. Worth 《Sportwissenschaft》2016,46(4):294-304
Motor performance is an important health resource. Review articles revealed a decline of motor performance of approximately 10?% between 1975 and 2006. In the past most of the data available for such comparisons came from ad hoc studies with non-standardized methods. Within the framework of the ”Motorik-Modul“ (MoMo) study as part of the German Health Interview and Examination Survey for Children and Adolescents (KiGGS), it is possible for the first time to directly compare two cohorts in the ages of 4–17 years in a nationally representative database for Germany. The aim of this article is to report changes in motor performance of children and adolescents in the time period 2003–2006 (cohort baseline n = 4528) compared to 2009–2012 (cohort wave 1, n = 2820). Overall, it is clearly shown that the motor performance of children and adolescents in Germany did not decrease within the observational period of 6 years. The comparison of mean values of the baseline cohort compared to those of wave 1 showed that 28 out of 52 mean values of the two cohorts with a high probability did not differ based on 95?% confidence intervals (CI). In 24 out of the 52 mean values positive changes could be noted based on the individual 95?% CI values. There were more positive changes in primary school aged children than in other age groups. Within these positive changes, most effect sizes were small to medium. The results indicate that recent activities aiming at elevating motor performance levels may have started to make an impact and should be expanded, also in secondary schools. The comparative cohort study presented in this article is currently being checked by the ongoing MoMo wave 2 survey of 2014–2017. 相似文献
134.
This article explores young women's accounts of the role that school sex education had in their learning about sex. It focuses on the influence of school sex education on behaviour, the importance of timing in understanding its utility, and the extent to which other sources of information complement or supplement school sex education. Thirty in-depth interviews and eight group discussions were conducted with female pupils from six schools in the east of Scotland. Nearly all of those interviewed cited school as a useful source in learning about sex. In particular, lessons intended to develop pupils' skills were valued. These were thought likely to influence behaviour positively in the future, although only one person could illustrate how this had already happened. A common feature of accounts was that school sex education had been delivered 'too late' for themselves or their peers, and it tended to be seen as an introduction or as supplementary to other sources, particularly friends, magazines and mothers. The utility of school sex education should not be dismissed but more attention should be given to the needs of those who become sexually active in their early teens. 相似文献
135.
This paper presents a mixture item response tree (IRTree) model for extreme response style. Unlike traditional applications of single IRTree models, a mixture approach provides a way of representing the mixture of respondents following different underlying response processes (between individuals), as well as the uncertainty present at the individual level (within an individual). Simulation analyses reveal the potential of the mixture approach in identifying subgroups of respondents exhibiting response behavior reflective of different underlying response processes. Application to real data from the Students Like Learning Mathematics (SLM) scale of Trends in International Mathematics and Science Study (TIMSS) 2015 demonstrates the superior comparative fit of the mixture representation, as well as the consequences of applying the mixture on the estimation of content and response style traits. We argue that methodology applied to investigate response styles should attend to the inherent uncertainty of response style influence due to the likely influence of both response styles and the content trait on the selection of extreme response categories. 相似文献
136.
Ella Daniel Maya Benish-Weisman Joanne N. Sneddon Julie A. Lee 《Child development》2020,91(5):1615-1630
Little is known about how children's value priorities develop over time. This study identifies children's value priority profiles and follows their development during middle childhood. Australian children (N = 609; ages 5–12 at Time 1) reported their values over 2 years. Latent Transition Analysis indicated four profiles: Social-Focus, Self-Focus, Growth-Focus and Undifferentiated. Within person development was characterized by profile stability or transfer to the Social-Focus profile. Younger children were more likely to have an Undifferentiated profile (or Self-Focus among boys) than older ones. Girls were more likely to have a Social-Focus profile or transfer to it, and less likely to have a Self- or Growth-Focus profile than boys. Social-Focus profile membership over time predicted more prosocial and less aggressive behavior. 相似文献
137.
Daniel C. Kopala-Sibley Marilyn Cyr Megan C. Finsaas Jonathan Orawe Anna Huang Nim Tottenham Daniel N. Klein 《Child development》2020,91(1):110-128
Seventy-nine 3-year olds and their mothers participated in a laboratory-based task to assess maternal hostility. Mothers also reported their behavioral regulation of their child. Seven years later, functional magnetic resonance imaging data were acquired while viewing emotional faces and completing a reward processing task. Maternal hostility predicted more negative amygdala connectivity during exposure to sad relative to neutral faces with frontal and parietal regions as well as more negative left ventral striatal connectivity during monetary gain relative to loss feedback with the right posterior orbital frontal cortex and right inferior frontal gyrus. In contrast, maternal regulation predicted enhanced cingulo-frontal connectivity during monetary gain relative to loss feedback. Results suggest parenting is associated with alterations in emotion and reward processing circuitry 7–8 years later. 相似文献
138.
Tae Kyoung Lee Alan Meca Jennifer B. Unger Byron L. Zamboanga Lourdes Baezconde-Garbanati Melinda Gonzales-Backen Elma I. Lorenzo-Blanco Miguel Á. Cano Sabrina E. Des Rosiers Daniel W. Soto Juan A. Villamar Monica Pattarroyo Karina M. Lizzi José Szapocznik Seth J. Schwartz 《Child development》2020,91(1):78-95
Acculturation consists of multiple domains (i.e., cultural practices, identifications, and values). However, less is known about how acculturation processes influence each other across multiple domains of acculturation. This study was designed to investigate transition patterns of acculturative processes within and across domains in a sample of 302 recent-immigrant Hispanic adolescents, Mage (SD) = 14.51 years (0.88) at baseline; male = 53%). Adolescents were assessed six times over a 3-year period. Latent profile analyses identified two profiles (high [or increasing] vs. low) for each domain at each timepoint. We found largely stable transition patterns in each domain over six timepoints. Importantly, sequential associations among profiles in acculturation domains were also detected. Implication for acculturation theory and research are discussed. 相似文献
139.
Educational Studies in Mathematics - Teaching mathematical modeling is a demanding task. Thus, fostering teachers’ competencies in this regard is an essential component of teacher education.... 相似文献
140.
Walter Hahn Guy Cellerier Wolfgang Wilhelm Jindra Kulich Robert J. Havighurst Bryan T. Peck Annegret Körner Rodney Skager Renate Nestvogel J. H. Sislian John J. Bergen Peter W. Kahl Tony Bates 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》1978,24(4):523-544