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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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ABSTRACT

With increasing demand for improved medical equipment and healthcare, next-generation biomedical engineers need strong design skills. Equipping biomedical engineering students with tools for idea generation and development can increase student design success. Design Heuristics are an ideation tool developed through empirical studies of product designs. While identified in the mechanical engineering space, Design Heuristics may be applicable in biomedical engineering design. In our study, we implemented a Design Heuristics session during upper-level undergraduate and first-year graduate biomedical engineering design courses. We examined the applicability of Design Heuristics within individual and team concept generation contexts. The findings demonstrated that biomedical engineering students were able to use Design Heuristics to generate multiple concepts, and that initial concepts produced using Design Heuristics were carried over into final team design. The results support the applicability of Design Heuristics to student idea generation in biomedical engineering design.  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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