水稻种子萌发过程中贮藏蛋白降解的研究概述

水稻种子贮藏蛋白分为水溶性清蛋白、醇溶性蛋白、盐溶性球蛋白和稀酸或稀碱溶性谷蛋白,其中以谷蛋白为主;水稻种子贮藏蛋白的降解与蛋白酶活性密切相关,它的降解过程受赤霉素、脱落酸、多效唑、茉莉酸甲酯等植物生长物质调控.     

Measuring the earnings returns to lifelong learning in the UK

This paper examines the earnings returns to learning that takes place following the conventional ‘school-to-work’ stage of the life-course. We operationalise such ‘lifelong learning’ as the attainment of certified qualifications in adulthood, following the completion of the first period of continuous full-time education. Using data from the British Household Panel Survey (BHPS) for the period 1991–2006, our approach and findings represent an important addition to the existing evidence base. By using annual data, we are able to employ the fixed effects estimator, which eliminates the problem of time-invariant unobserved heterogeneity. Our dynamic specification uses a lag structure to consider how earnings returns evolve in the medium and longer run, whilst also controlling for wage trends which were evident prior to qualification attainment. Our results show a medium-run return for women of 10% on hourly wages. For men, initial suggestions of a similar positive return are eliminated once pre-qualification trends are taken into account. This suggests that adult learning has a causal effect on women's subsequent earnings but, for men, any apparent gain is due to selection.     

Preparing School Counselors to Promote Academic Development

Reform in school counseling over the last decade has focused on how school counselors can contribute to the academic development of K–12 students. Consensus in this matter has yet to be achieved, and recommendations about how best to prepare preservice K–12 school counselors for this objective have been incomplete. The authors describe content and supervised experiences from a preservice course designed to prepare school counselors to promote student academic development.     

Beyond Warmth and Conflict: The Developmental Utility of a Boundary Conceptualization of Sibling Relationship Processes

Translating relationship boundaries conceptualizations to the study of sibling relationships, this study examined the utility of sibling enmeshment and disengagement in predicting child adjustment difficulties in a sample of 282 mothers and adolescents (mean age = 12.7 years). Mothers completed a semistructured interview at the first measurement occasion to assess sibling interaction patterns. Adolescents, mothers, and teachers reported on children’s adjustment problems across 2 annual waves of assessment. Supporting the incremental utility of a boundary conceptualization of sibling relationships, results of latent difference score analyses indicated that coder ratings of sibling enmeshment and disengagement uniquely predicted greater adolescent adjustment difficulties even after taking into account standard indices of sibling relationship quality (i.e., warmth and conflict) and sibling structural characteristics (e.g., sex).     

A case study of one instructor’s lecture-based teaching of proof in abstract algebra: making sense of her pedagogical moves

This paper is a case study of the teaching of an undergraduate abstract algebra course, in particular the way the instructor presented proofs. It describes a framework for proof writing based on Selden and Selden (2009) and the work of Alcock (2010) on modes of thought that support proof writing. The paper offers a case study of the teaching of a traditionally-taught abstract algebra course, including showing the range of practice as larger than previously described in research literature. This study describes the aspects of proof writing and modes of thought the instructor modeled for the students. The study finds that she frequently modeled the aspects of hierarchical structure and formal–rhetorical skills, and structural, critical, and instantiation modes of thought. This study also examines the instructor’s attempts to involve the students in the proof writing process during class by asking questions and expecting responses. Finally, the study describes how those questions and responses were part of her proof presentation. The funneling pattern of Steinbring (1989) describes most of the question and answer discussions enacted in the class with most questions requiring a factual response. Yet, the instructional sequence can be also understood as modeling the way an expert in the discipline thinks and, as such, offering a different type of opportunity for student learning.     

Goal self-concordance moderates the relationship between achievement goals and indicators of academic adjustment

This study examined whether the good or bad outcomes associated with mastery- and performance-approach achievement goals depend on the extent to which these goals are pursued for self-concordant reasons. A sample of 220 undergraduate students completed measures of achievement goals, goal self-concordance, academic satisfaction, and academic anxiety before mid-term exams. A total of 115 participants completed a follow-up measure of their semester GPA. Results of moderated regressions revealed that mastery-approach goals were positively associated with academic satisfaction and performance, but only for students with high levels of mastery goal self-concordance. Performance-approach goals were also associated with higher performance, but only for students with high levels of performance goal self-concordance. Both types of goals were positively associated with anxiety for individuals with low levels of goal self-concordance. This study illustrates the importance of considering the joint influence of goal content and goal motivation in their association with consequential educational outcomes.     

Factors influencing school connectedness: Chinese adolescents’ perspectives

This study explored the concept of school connectedness and the factors that may influence its development with a sample of Chinese adolescents. Six focus groups involving 52 high school students were conducted using a set of predetermined discussion topics. Results indicated that the students fully understood the notion of school connectedness and could identify a number of key influences affecting its development. These factors could be grouped under several domains including teacher care, peer relations, broader school relationships, school disciplinary policies and practices, activities within the school’s guidance and counseling program, and opportunities for talent development. The students were also able to suggest practical strategies that schools might introduce to enhance and strengthen students’ acquisition of connectedness to school. The implications from the findings are discussed with particular reference to implementing comprehensive school guidance and counseling program in Hong Kong.     

Students’ images of two-variable functions and their graphs

This paper presents a conceptual analysis for students’ images of graphs and their extension to graphs of two-variable functions. We use the conceptual analysis, based on quantitative and covariational reasoning, to construct a hypothetical learning trajectory (HLT) for how students might generalize their understanding of graphs of one-variable functions to graphs of two-variable functions. To evaluate the viability of this learning trajectory, we use data from two teaching experiments based on tasks intended to support development of the schemes in the HLT. We focus on the schemes that two students developed in these teaching experiments and discuss their relationship to the original HLT. We close by considering the role of covariational reasoning in generalization, consider other ways in which students might come to conceptualize graphs of two-variable functions, and discuss implications for instruction.     

Does it matter who your schoolmates are? An investigation of the association between school composition,school processes and mathematics achievement in the early years of primary education

Although many studies have focused on the importance of school composition for student achievement, there is still no consensus on whether school composition matters to student achievement, and, if so, why. Therefore, the present study investigates the association between school composition and mathematics achievement at the end of second grade in Flanders. International research points to the initial ability level, SES, ethnicity and sex composition of the school as potential variables in explaining differences in student achievement. Moreover, some researchers suggest that schools ‘react’ to their student body and for that reason we investigated the possible association between school composition and school processes. Data from the SiBO Project have been analyzed using multilevel regression and multilevel mediation analysis. The results showed no direct school composition effects with respect to prior achievement, SES, ethnicity and sex on math achievement. We found two small differential effects, indicating that mean school prior achievement seems to positively affect initially high achievers, and the proportion of minority students in school seems to negatively affect students speaking a non‐European language except for Turkish, Arabic or Berber at home. Furthermore, two small indirect effects were found which suggest that schools with a high mean prior achievement or a high mean SES keep in regular contact with their students' parents and this, in turn, appears to enhance students' math achievement. Overall, our results seem to indicate that school composition in the early years of primary education hardly matters.     

‘Behind the teacher's back’: an ethnographic study of deaf people's schooling experiences in the Republic of Ireland

Historically, the valuing of deaf children's voices on their own schooling has been underrepresented in educational policies, curriculum frameworks and discursive practices and, in particular, in the debates and controversies surrounding oralism and Irish Sign Language in deaf education in Ireland. This article discusses children's everyday lived experiences of oralism and Irish Sign Language using ethnographic interviews and observational methods. The data yielded narrative understandings of how deaf children's schooling experiences served as a cauldron for the development of time, space and relational domains for individual and collective self-expression, cultural production and reproduction of the secret lore and understandings of Irish Sign Language and development of a hidden curriculum of sign language in a policy and practice context dominated by oralism. This paper concludes with recommendations for the development of a sign bilingual curriculum across the full scope and sequence of schooling in Ireland.