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951.
952.
Handedness has been studied for association with language-related disorders because of its link with language hemispheric dominance. No clear pattern has emerged, possibly because of small samples, publication bias, and heterogeneous criteria across studies. Non-right-handedness (NRH) frequency was assessed in N = 2503 cases with reading and/or language impairment and N = 4316 sex-matched controls identified from 10 distinct cohorts (age range 6–19 years old; European ethnicity) using a priori set criteria. A meta-analysis (Ncases = 1994) showed elevated NRH % in individuals with language/reading impairment compared with controls (OR = 1.21, CI = 1.06–1.39, p = .01). The association between reading/language impairments and NRH could result from shared pathways underlying brain lateralization, handedness, and cognitive functions.  相似文献   
953.
954.
Social loafing refers to the tendency for individuals to reduce their own personal input when performing as part of group. This phenomenon may be problematic if it exists in educational contexts, given a current emphasis on group collaborative classroom activities. The present study investigated whether social loafing existed in a collaborative educational task, employing groups of three and eight participants. The results indicated that individuals working within the smaller groups were more productive than those working in larger groups, consistent with the social loafing hypothesis. Future research should determine whether the detrimental effects on students' collaborative performance attributable to social loafing are justifiable in terms of gains accrued in other (e.g. interpersonal) domains.  相似文献   
955.
This study describes pre-kindergarten teachers’ use of kindergarten transition practices and examined the extent to which these practices were associated with kindergarten teachers’ judgments of children's social, self-regulatory, and academic skills upon their entry into kindergarten. Participants were 722 children from 214 pre-kindergarten classrooms participating in the National Center for Early Development and Learning's (NCEDL) Multi-State Pre-kindergarten Study. Of nine transition practices intended to promote children's adaptation to kindergarten, pre-kindergarten teachers reported implementing, on average, six transition practices, with notable variation across pre-kindergarten classrooms. Children were judged by their kindergarten teachers to have more positive social competencies and fewer problem behaviors when they attended pre-kindergarten classrooms in which more transition activities were implemented and, specifically, in which teachers discussed curricula or specific children with kindergarten teachers. In addition, positive associations between kindergarten teachers’ perceptions of children's social competence and pre-kindergarten transition activities (total number of activities and activities that children experience directly) were stronger for children who experienced social and economic risks. Implications of these findings related to alignment across the pre-kindergarten to kindergarten settings to improve children's school readiness are discussed.  相似文献   
956.
This paper reports on the findings of a 1999 study that set out to investigate the current perceptions of students and teachers towards the use of portable computers at a secondary school. The aim was to compare these with the findings of a 1995 study carried out by the researcher at the same school. Data were collected from 102 Year Twelve students (17 year old), 104 Year Eight students (13 year old) and 40 teachers. The results indicated that for the Year Twelve students the computers had been of limited value while the Year Eight students appeared to be divided with about a quarter indicating negative attitudes. For the younger students the computers appeared to be used more often and for a greater range of tasks. Many teachers indicated concerns about the management of computers in the classroom and linking computer use to learning outcomes. These perceptions underline the need for targeted professional development, systematic support for the development of student computer-related skills, and changes in the curriculum towards more learner-centred approaches.  相似文献   
957.
Objective:The primary objective of this study was to determine how community college health sciences librarians perceive their proficiencies in the essential skills, knowledge, and abilities necessary for the practice of a health information professional as defined by the Medical Library Association (MLA) Competencies for Lifelong Learning and Professional Success. A secondary objective was to determine their current level of engagement with the professional community and identify barriers to further professional development.Methods:A survey was posted to various email discussion lists, and volunteer follow-up interviews were conducted.Results:The survey was completed by seventy-five community college health sciences librarians, and seven follow-up interviews were performed. Survey results indicated that community college health sciences librarians perceived themselves as having intermediate or advanced intermediate proficiency in the six MLA competencies. Survey and interview results indicated that community college health sciences librarians were engaged with the profession and faced the same barriers to continued professional development and continued education as other academic librarians.Conclusion:The results affirm that community college librarians who are responsible for collections and services in the health sciences meet the MLA competencies, which fills a gap in the literature regarding how these librarians develop professional competencies and are involved in professional associations. The results suggest that community college librarians can improve their skill levels by continuing their education and following trends in the literature.  相似文献   
958.
Electronic field tripping is a relatively new form of large‐scale distance education that attempts to provide contextually rich learning materials embedded within a coherent educational content base. Using Dewey’s (1943 Dewey, J. 1943. The child and the curriculum: the school and society, Chicago: University of Chicago Press.  [Google Scholar]) framework for the natural learning impulses of children, we describe the potential pedagogical benefits afforded by electronic field trips (EFTs). We outline a shift in distance education from a techno‐centric focus on hardware and logistics to the inherent features of children’s desires to explore their world, which represents an alteration of perspective and purpose in understanding computer technologies in classroom settings. Finally, we demonstrate that while each independent element of the EFT experience promotes one or more of Dewey’s impulses, bringing together all the resources provided for EFTs fosters deeper connections, more engaged learning, and contextualized distance learning true to the spirit of live field trips.  相似文献   
959.
34 children were observed in infant play groups. 2 sets of infant behaviors were coded: assertive acts and attempts to communicate with adults. No sex differences were observed at 13 to 14 months in any of these behaviors. However, adults attended to girls' assertive behaviors far less of the time than to boys' assertive behaviors. They attended more to girls' less intense communication attempts and to boys' more intense attempts. When 29 of the same children were observed in toddler play groups no more than 11 months later, there were sex differences in behavior. Boys were more assertive; girls talked to teachers more. Teachers no longer differentiated their responses to boys and girls. Peers reacted more to boys' assertive behavior than to girls.' We hypothesized that caregivers may use stereotypes to guide their reactions to infants because infant behavior is ambiguous. For the toddlers, behavior had become more defined, and caregivers reacted to the behaviors. By using the sex stereotype to guide their reactions to younger children, the caregivers may have perpetuated the stereotype.  相似文献   
960.
In this study, an electro-mechanical valve (EMV) system for the intake valve ofa fottr stroke, single cylinder, overhead valve and spark ignition (SI) engine was designed and constructed. An engine with the EMV system and a standard engine were tested to observe the effects of the EMV on engine performance and emissions at different speeds under full load. The EMV engine showed improved engine power, engine torque and break specific fuel consumption (BSFC). A 66% decrease in CO emissions was also obtained with the EMV system, but hydrocarbons (HC) and NOx emissions increased by 12% and 13% respectively.  相似文献   
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