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941.
The enzyme theory and the origin of biochemistry 总被引:3,自引:0,他引:3
942.
A study is made of the orthogonal polynomials on certain curves in the complex plane. Necessary and sufficient conditions for a set of polynomials to be orthogonal on the curves are obtained in terms of symmetric matrices. The relations of the symmetric matrices to Toeplitz matrices and innerwise matrices are shown. 相似文献
943.
In response to both problematic and extant gaps in Bachelor??s degree completion rates, this mixed methods study investigated whether a theoretically based undergraduate course intervention measurably contributed to participants?? competence as self-regulated learners. Respective quantitative and qualitative analyses of data collected from two samples showed that intervention participants experienced growth in the targeted self-regulatory constructs. Moreover, differential effects by race/ethnicity and gender were not observed. We conclude with a discussion of this study??s implications for institutions of higher education, pertinent considerations in designing and implementing this self-regulated learning intervention, and a review of the literature on effective practices for doing so. 相似文献
944.
This observational study examined kindergarteners’ (n = 170) exposure to literacy instruction in their classrooms (n = 36), child-by-instruction interactions, and behavioral engagement in relation to literacy skills. Time spent in four instructional contexts was coded according to who managed children's attention (teacher-managed, TM or child-managed, CM), and the content focus (basic skills such as teaching letters and their sounds, or meaning-focused such as discussing a book); children's behavioral engagement and off-task behavior were also coded live five times over the year. Word-reading and phonological awareness skills were assessed in fall and spring. Hierarchical Linear Modeling results indicated that kindergarteners with lower initial skills gained more in word-reading, but not phonological awareness, when they were exposed to relatively more time in TM basic skills instruction. In contrast, more time in CM meaning-focused instruction did not interact with initial skills to predict either outcome. Engagement analyses indicated that students were more likely to be off-task in CM than in TM contexts. Children who spent more time off-task during TM contexts had lower spring scores on both outcomes. Discussion explores the implications of this work for both literacy learning and behavioral engagement in the transition year of kindergarten. 相似文献
945.
Previous research has demonstrated that preschoolers can use situation-specific (e.g., visual access) and person-specific (e.g., prior accuracy) cues to infer what others know. The present studies investigated whether 4- and 5-year-olds appreciate the differential informativeness of these types of cues. In Experiment 1 (N = 50), children used others' prior labeling accuracy as a cue when learning labels for, but not the visual identity of, hidden objects. In Experiment 2 (N = 64), with both cues present, children attended more to visual access than prior accuracy when learning the visual identity of, but not labels for, hidden objects. These findings demonstrate that children appreciate the difference between situation- and person-specific cues and flexibly evaluate these cues depending on what information they are seeking. 相似文献
946.
Previous work has shown that mothers' employment is associated with increases in children's body mass index (BMI), a measure of weight for height. Nonstandard work (working evenings or nights, weekends, or an irregular shift) may also be associated with children's BMI. This article examines the association between maternal work and children's BMI and considers the influence of mothers' nonstandard work schedules. Using data from school-age children (approximately 8 to 12 years) in the NICHD's Study of Early Child Care and Youth Development (N = 990), this study found that an increase in the total time a mother is employed is associated with an increase in her child's BMI; additionally, the association between maternal employment and children's weight is much stronger at 6th grade relative to younger ages. There was no evidence that maternal or home characteristics or children's time use mediated these associations, nor was there any evidence that nonstandard work was associated with children's BMI. Implications for policy and future research are discussed. 相似文献
947.
For postdocs to have the best chances of achieving their career goals they need to not only acquire discipline-specific research
experience, but also additional generic skills vital for future employment inside or outside academia. They also require access
to information and mentoring that will help them strategically plan and make informed decisions about their future. Few studies
have examined the variables that impact the postdoctoral experience or research productivity. Thus, a comprehensive survey
was conducted to determine whether quality supervision, career mentoring, collaboration, networking and a nurturing research
environment makes a positive difference in the experiences and productivity of postdoctoral researchers. Unsurprisingly, the
survey revealed that job insecurity and lack of a career structure are ongoing concerns for postdocs. However, a clear association
was shown between quality supervision, for example, in conveying the importance of taking responsibility for their future
academic career by strengthening their track record, and the number of peer-reviewed publications produced. The findings also
suggest that mentoring in non-academic career paths can be greatly improved. The results of this study have guided a research-intensive
Australian University to implement initiatives and programs which enhance the postdoctoral experience. Finally this work raises
awareness of the crucial contributions postdocs make to the research output and environment of universities. 相似文献
948.
John T.E. Richardson 《教育心理学》2011,31(2):123-139
At UK institutions of higher education, the academic attainment of White students tends to be higher than that of students from other ethnic groups. A postal survey of Open University students found very little difference in academic engagement in those from different ethnic groups. The differences in pass rates and course grades remained statistically significant even when any effects of differences in academic engagement had been controlled. This is consistent with previous findings that quantitative variations in the attainment of students from different ethnic groups are not reflected in concomitant qualitative variations in their experience of higher education. The explanation for the attainment gap in ethnic minority students must be sought elsewhere than in the nature of their experience of higher education. 相似文献
949.
950.
Engineering curricula have expanded in recent decades. In addition to science and technical engineering, they now include several non-technical competencies. This is a trend reinforced by programme accreditation. The authors take the viewpoint that it is important to ensure that graduates have the competencies they will require for their work. The following question is addressed: What are the generic competencies that engineers graduating in Australia require for their work as engineers?
Competencies were identified from a broad range of literature and then rated by 300 established engineers for importance to their jobs. The results indicated that non-technical, attitudinal and technical competencies were perceived to be important. Eleven competency factors were revealed empirically. Profiles of these competency factors among graduates would assist evaluation and improvement of engineering programmes. This is the first quantitative study conducted in Australia that encompassed all engineering disciplines and focused on established engineers rather than recent graduates. 相似文献