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Shoudong Wang Shulin Liu Jie Wang Kengo Yokosho Bin Zhou Ya-Chi Yu Zhi Liu Wolf B Frommer Jian Feng Ma Li-Qing Chen Yuefeng Guan Huixia Shou Zhixi Tian 《国家科学评论(英文版)》2020,7(11):1776
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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The purpose of this study was to assess receptivity to peer teaching and peer learning about the safe and appropriate use of medications among communitydwelling older adults. The sample was predominately White (88.5%), female (75.9%) older adults with an average age of 80.2 ( - 9.1) years. On average, the participants perceived their health status as good (2.8 - 0.6). In addition, participants reported using an average number of 4.4 ( - 3.3) prescribed medications. The majority (75%) of participants also reported no problems with their medications. With respect to receptivity to peer teaching and peer learning, the participants, on average, were neutral to peer teaching (6.0 - 2.4), but were somewhat receptive to peer learning (6.7 - 2.2). The number of prescribed medications that a participant reported taking and the age of a participant were identified as significant predictors of receptivity to peer teaching and accounted for 14.5% of the total variance ( F = 5.84, df = 2, p = 0.005). For receptivity to peer learning, the number of prescribed medications also was a significant predictor ( F = 7.50, df = 1, p = 0.008). This study provides the initial step to identifying community-dwelling older adults who would be receptive to peer teaching and peer learning about the safe and appropriate use of medications. 相似文献
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With the advent of the Next Generation Science Standards in engineering (NGSS, 2013), teachers of multiple subject areas are being asked to do more than ever before—not only to teach engineering content in the K-12 classroom but also to engage students in authentic disciplinary reading and writing as part of content learning. These standards sound good, but they beg several questions; namely, what do we know about how, why, and when do engineers read and write as they do their work every day? What do teachers charged with engineering education know about the daily practices of engineers, let alone the literacy practices? In short, little is known about the literacy practices of engineers in the course of their daily work. This article draws on participant observation, interviews, and document analysis of one research engineering laboratory to illustrate the literacy practices of one group of engineers and begins to draw implications from this work for teacher practice in achieving the NGSS engineering education standards. 相似文献
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This study examines how parent socioeconomic status (SES) directly and indirectly predicts children's school readiness through pathways of parental investment. Data come from direct assessments with preschool children and surveys with their primary caregivers in Ghana at the start of the 2015–2016 school year (N = 2,137; Mage = 5.2 years). Results revealed SES-related gaps in all parental investment characteristics and child school readiness skills. Preschool involvement served as the primary mediating mechanism in the path from SES to most school readiness skills, though it did not predict executive function. The number of books in the household was marginally positively predictive of early literacy, whereas at-home stimulation was negatively related to motor, literacy, and numeracy skills. 相似文献
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