Simultaneous changes in seed size,oil content and protein content driven by selection of SWEET homologues during soybean domestication

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.     

Scientific communication – on the brink of the next evolution?

Key points

• Publishing is fixated on the format of the scholarly article, and this is stifling innovation.
• Content should be presented in a way that adapts dynamically to the reader's needs.
• A lot of interdisciplinary research is needed to transform reading, writing, and publishing processes.

     

Designing Instructional Examples to Reduce Intrinsic Cognitive Load: Molar versus Modular Presentation of Solution Procedures

It is usually assumed that successful problemsolving in knowledge-rich domains depends onthe availability of abstract problem-typeschemas whose acquisition can be supported bypresenting students with worked examples.Conventionally designed worked examples oftenfocus on information that is related to themain components of problem-type schemas, namelyon information related to problem-categorymembership, structural task features, andcategory-specific solution procedures. However,studying these examples might be cognitivelydemanding because it requires learners tosimultaneously hold active a substantial amountof information in working memory. In ourresearch, we try to reduce intrinsic cognitiveload in example-based learning by shifting thelevel of presenting and explaining solutionprocedures from a `molar' view – that focuseson problem categories and their associatedoverall solution procedures – to a more`modular' view where complex solutions arebroken down into smaller meaningful solutionelements that can be conveyed separately. Wereview findings from five of our own studiesthat yield evidence for the fact thatprocessing modular examples is associated witha lower degree of intrinsic cognitive load andthus, improves learning.     

Household Socioeconomic Status and Parental Investments: Direct and Indirect Relations With School Readiness in Ghana

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; M_age = 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.     

Eine Methode zur Konstruktion robuster Klassenhierarchien

Zusammenfassung. In diesem Beitrag wird eine Methode zur Konstruktion robuster Klassenhierarchien vorgestellt. Hierzu wird aus den überlegungen bezüglich der polymorphen Verwendung von Klassen [2] eine Vorgehensweise zur Konstruktion von Klassenhierarchien abgeleitet. Die Begriffe Konformit?t und Spezialisierung werden verfeinert, indem nicht mehr s?mtliche Methoden einer Klasse, sondern Teilmengen davon betrachtet werden. Dies führt zum Begriff der partiellen Konformit?t. In Erweiterung von [2] sind partiell konforme Klassen dann polymorph verwendbar, wenn der Anwendungskontext, der sich aus der Benutzung der Klasse ergibt, sich ausschlie?lich auf konforme Methoden erstreckt. Diese Eigenschaft ist statisch zur übersetzungszeit überprüfbar. Damit k?nnen Fehlbenutzungen bereits zur übersetzungszeit ausgeschlossen werden. Eingegangen am 24. Dezember 1996 / Angenommen am 15. Oktober 1997