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991.
This study examined 33 mothers' and preschoolers' oral language skills (decontextualized discourse) across an emergent reading, shared reading, and oral storytelling interaction. The sample comprised primarily African American families from various socioeconomic backgrounds, ranging from Head Start families to middle-income families. Two measures of decontextualized language were assessed—literate language features and type of talk (i.e., a coding scheme categorizing comments/questions on a continuum from contextualized to decontextualized talk). Mothers used more decontextualized language during the oral storytelling interaction versus the other interactions, but children used more during the emergent reading interaction. Mothers with advanced literacy skills were more likely to make decontextualized comments/questions and use mental/linguistic verbs during the interactions. Results are discussed in terms of implications for parent-child home literacy interventions.  相似文献   
992.
This article provides a brief review of current large-scale, longitudinal data collection initiatives focusing on children. These studies will be available for secondary data analyses in the twenty-first century. In addition to child outcome data, process-oriented information is being collected on child-parent interactions, quality of child care, elementary school teacher reports and classroom observations, accessibility and use of health, educational and social services, parental mental health, family violence, fathering, parental residence patterns, income and income sources, child support, employment patterns, and community characteristics. Several of these studies are randomized trials of the efficacy of early childhood intervention services and housing mobility programs. The usefulness of these efforts for exploring policy-relevant issues (child support enforcement, work requirements for welfare recipients, antipoverty strategies, housing subsidies and relocation, availability of child care, child-care subsidies) are discussed.  相似文献   
993.
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   
994.
采用录像观察统计法、问卷调查法等研究方法,根据自由体操发展趋势和规则,在对世界自由体操发展现状和动作技术的演进过程分析基 础上,找出其潮流动作,揭示其发展规律,为基本难度动作的选择提供依据;并确立新规则下11~12 岁少年男体操运动员自由体操主要基本难度 动作系列。  相似文献   
995.
The effectiveness of a nap as a recovery strategy for endurance exercise is unknown and therefore the present study investigated the effect of napping on endurance exercise performance. Eleven trained male runners completed this randomised crossover study. On two occasions, runners completed treadmill running for 30?min at 75% ?O2max in the morning, returning that evening to run for 20?min at 60% ?O2max, and then to exhaustion at 90% ?O2max. On one trial, runners had an afternoon nap approximately 90?min before the evening exercise (NAP) whilst on the other, runners did not (CON). All runners napped (20?±?10?min), but time to exhaustion (TTE) was not improved in all runners (NAP 596?±?148?s vs. CON 589?±?216?s, P?=?.83). Runners that improved TTE after the nap slept less at night than those that did not improve TTE (night-time sleep 6.4?±?0.7?h vs. 7.5?±?0.4?h, P?r2 ? =??0.76, P?=?.001). In runners that improved TTE, ratings of perceived exertion (RPE) were lower during the TTE on NAP than CON compared to runners that did not improve (?0.4?±?0.6 vs. 0?±?0, P?=?.05). Reduced exercising sense of effort (RPE) may account for the improved TTE after the nap. In conclusion, a short afternoon nap improves endurance performance in runners that obtain less than 7?h night-time sleep.  相似文献   
996.

This study examined to what extent teacher–student conflict and closeness, on the one hand, and students’ self-concepts of ability in literacy and mathematics, on the other, are related to students’ achievement emotions (enjoyment, anxiety and boredom) in mathematics and literacy among Finnish early adolescents (N = 854). We also investigated the extent to which these associations are moderated by student temperament (surgency/extraversion, negative affectivity and effortful control). The results showed, after accounting for relevant covariates, that in both school subjects, teacher–student conflict was negatively related to enjoyment and positively to anxiety and boredom, whereas teacher–student closeness was positively related to enjoyment and negatively to boredom. Self-concepts of ability in both school subjects were positively related to enjoyment and negatively to anxiety, whereas the self-concept of ability was only negatively related to boredom in mathematics. Student temperament also moderated some of the associations in the literacy domain. Lower levels of conflict in the teacher–student relationship were related to higher levels of enjoyment in literacy, particularly among students who had lower levels of surgency/extraversion. Also, a closer relationship with the teacher or a lower self-concept of ability in literacy was related to higher levels of anxiety, particularly among students who had low effortful control. In the mathematics domain, the associations between the self-concept of ability and achievement emotions were somewhat stronger than in literacy, and the domain-specific associations were not dependent on student temperament.

  相似文献   
997.
Mobile and Ubiquitous Learning (m/u-learning) are finding an increasing adoption in education. They are often distinguished by hybrid learning environments that encompass elements of formal and informal learning, in activities that happen in distributed settings (indoors and outdoors), across physical and virtual spaces. Despite their purported benefits, these environments imply additional complexity in the design, monitoring and evaluation of learning activities. The research literature on learning design (LD) and learning analytics (LA) has started to deal with these issues. This paper presents a systematic literature review of LD and LA, in m/u-learning. Apart from providing an overview of the current research in the field, this review elicits elements of common ground between both communities, as shown by the similar learning contexts and complementary research contributions, and based on the research gaps, proposes to: address m/u-learning beyond higher education settings, reinforce the connection between physical and virtual learning spaces, and more systematically align LD and LA processes.  相似文献   
998.
This study investigated reciprocal relations between adolescents' physical aggression and their perceptions of peers' deviant behaviors and attitudes. Analyses were conducted on four waves of data from 2,290 adolescents (ages 10–16) from three urban middle schools. Autoregression models revealed reciprocal relations between peer factors (i.e., friends' problem behavior, peer pressure for fighting, friends' support for fighting) and adolescents' reporting of their aggressive behavior. Bidirectional relations were also found between peer pressure for fighting and adolescents' frequency of physical aggression based on teacher ratings. Findings were consistent across sex, grade, and time. Findings suggest that multiple dimensions of peers' behaviors uniquely play a role in the development of adolescents' aggression and have important implications for interventions to reduce problem behaviors.  相似文献   
999.
The Covid-19 pandemic has driven the fastest changes to higher education across the globe, necessitated by social distancing measures preventing face-to-face teaching. This has led to an almost immediate switch to distance learning by higher education institutions. Anatomy faces some unique challenges. Intrinsically, anatomy is a three-dimensional subject that requires a sound understanding of the relationships between structures, often achieved by the study of human cadaveric material, models, and virtual resources. This study sought to identify the approaches taken in the United Kingdom and Republic of Ireland to deliver anatomical education through online means. Data were collected from 14 different universities in the United Kingdom and Republic of Ireland and compared adopting a thematic analysis approach. Once themes were generated, they were collectively brought together using a strength, weakness, opportunity, threat (SWOT) analysis. Key themes included the opportunity to develop new online resources and the chance to engage in new academic collaborations. Academics frequently mentioned the challenge that time constrains could place on the quality and effectiveness of these resources; especially as in many cases the aim of these resources was to compensate for a lack of exposure to cadaveric exposure. Comparisons of the actions taken by multiple higher education institutions reveal the ways that academics have tried to balance this demand. Discussions will facilitate decisions being made by higher education institutions regarding adapting the curriculum and assessment methods in anatomy.  相似文献   
1000.
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   
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