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71.
Soybean accounts for more than half of the global production of oilseed and more than a quarter of the protein used globally for human food and animal feed. Soybean domestication involved parallel increases in seed size and oil content, and a concomitant decrease in protein content. However, science has not yet discovered whether these effects were due to selective pressure on a single gene or multiple genes. Here, re-sequencing data from >800 genotypes revealed a strong selection during soybean domestication on GmSWEET10a. The selection of GmSWEET10a conferred simultaneous increases in soybean-seed size and oil content as well as a reduction in the protein content. The result was validated using both near-isogenic lines carrying substitution of haplotype chromosomal segments and transgenic soybeans. Moreover, GmSWEET10b was found to be functionally redundant with its homologue GmSWEET10a and to be undergoing selection in current breeding, leading the the elite allele GmSWEET10b, a potential target for present-day soybean breeding. Both GmSWEET10a and GmSWEET10b were shown to transport sucrose and hexose, contributing to sugar allocation from seed coat to embryo, which consequently determines oil and protein contents and seed size in soybean. We conclude that past selection of optimal GmSWEET10a alleles drove the initial domestication of multiple soybean-seed traits and that targeted selection of the elite allele GmSWEET10b may further improve the yield and seed quality of modern soybean cultivars.  相似文献   
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In each of two studies, teachers were randomly assigned to either a Virtual Workshop (VW) group that used a computerized professional development program or an Actual Workshop (AW) group that participated in face-to-face professional development, including discussion, feedback, and collaboration. In both studies, teachers’ posttest scores related to their knowledge of the Question Exploration Routine and their plans for using it were significantly higher than their pretest scores. In Study 2, both groups’ posttest scores with regard to implementation and planning of the routine were significantly greater than their pretest scores. There were no significant differences between the groups at posttesting on any measure. The posttest knowledge scores of the whole groups of students and the subgroups of students with LD being taught by both groups of teachers were significantly higher than their pretest scores. All teachers indicated that they were satisfied with the training and the routine. VW teachers in both studies indicated that they were satisfied with the software program.  相似文献   
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Relationship violence is a salient concern on college campuses today, and psychoeducational groups may be an appropriate prevention format. This article describes a study measuring the impact of college student participation in the HEART (Help End Abusive Relationships Today) program, a series of group sessions designed to increase knowledge and awareness of relationship violence. Findings indicated significant changes for group participants postintervention. Implications and recommendations for college counselors are discussed.  相似文献   
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Counselors (N = 911) reported the research skills needed for practice and subsequent research training needs. Findings indicate that counselors have a high need for research skills at work, but training needs differ significantly by counselor type. Recommendations include increasing emphasis on single‐case design, survey design, and widely available data analysis tools.  相似文献   
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This study focuses on the relationships between meanings of science constructed in classrooms and sociocultural precepts of the wider society. Research presented is part of a larger study of the negotiation of knowledge and roles in high school science classrooms. The data presented document that what goes on in classrooms reflects and recreates societal attitudes towards work, in general, and teachers’ work, in particular. The teacher in this study reduces his demands for academic work in return for students’ cooperation and as a means of coping with negative aspects of teaching. Students, in turn, are not concerned about the specific subject matter of chemistry. What matters to them are the academic credentials that lead to success in the college and employment arenas. As a result, teacher and students construct school chemistry to be what you‐get‐through‐as‐you‐get‐along. The interdependence of the roles and actions of teachers and students suggests changes in policy and practice.  相似文献   
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ABSTRACT

This paper considers the examination results of TVEI and non TVEI pupils in the database established at the University of Newcastle in 1985‐87. The pupils took national exams in the summer of 1987, when they were about 16 years old. Their average grades (Exam Means) and their accumulated grades (Exam Totals) were considered separately.

The Exam Mean and Exam Total scores were generally worse for TVEI than non TVEI pupils, even when pupils with the same ability test scores and aspirational scores were compared. However, it is possible that non TVEI factors caused the discrepancy in results and it is these factors which are the subjects of this paper.

The paper considers firstly whether the differences are an artefact of regression analysis. Secondly, the data are considered using various multilevel models. Both analyses suggest that there was no TVEI effect on the Exam Mean score and a negative TVEI effect on the Exam Total. Various explanations for these findings, concerning internal school allocational and curriculum policies, are considered and discussed.  相似文献   
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