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For nearly 50 years, analyses of coral physiology have used small coral fragments (nubbins) to make inferences about larger colonies. However, scaling in corals shows that linear extrapolations from nubbins to whole colonies can be misleading, because polyps in nubbins are divorced of their morphologically complex and physiologically integrated corallum. We tested for the effects of integration among branches in determining size-dependent calcification of the coral Pocillopora spp. under elevated P CO 2 . Area-normalized net calcification was compared between branches (nubbins), aggregates of nubbins (complex morphologies without integration) and whole colonies (physiologically integrated) at 400 versus approximately 1000 µatm P CO 2 . Net calcification was unaffected by P CO 2 , but differed among colony types. Single nubbins grew faster than whole colonies, but when aggregated, nubbins changed calcification to match whole colonies even though they lacked integration among branches. Corallum morphology causes the phenotype of branching corals to differ from the summation of their branches. 

Abstract Leaf litter inputs can influence the structure and function of both terrestrial and adjacent aquatic ecosystems. Dioecy and herbivory are two factors that together have received little attention, yet have the potential to affect the quantity, quality, and timing of riparian litterfall, litter chemistry, and litter decomposition processes. Here, we explore litter chemistry differences for the dioecious Sitka willow ( Salix sitchensis Sanson ex. Bong), which is establishing on primary successional habitats at Mount St. Helens (WA, USA) and is heavily infested with a stem‐boring weevil ( Cryptorhynchus lapathi ). Weevil‐attacked branches produced summer senesced litter that had significantly higher %N, lower C:N ratios, and lower condensed tannins than litter from branches that were unattacked by the weevil and senesced naturally in the autumn. Weevils more often attack female willows; however, these common litter chemicals did not significantly differ between males and females within the weevil‐attacked and ‐unattacked groups. High‐resolution mass spectrometry was used to isolate compounds in litter from 10 Sitka willow individuals with approximately 1500–1600 individual compounds isolated from each sample. There were differences between weevil‐attacked litter and green leaf samples, but at this level, there was no clustering of male and female samples. However, further exploration of the isolated compounds determined a suite of compounds present only in either males or females. These findings suggest some variation in more complex litter chemistry between the sexes, and that significant differences in weevil‐attacked litter chemistry, coupled with the shift in seasonality of litter inputs to streams, could significantly affect in‐stream ecological processes, such as decomposition and detritivore activity. 

The need for a comprehensive, high-quality pipeline for the development of undergraduate pre-service teachers, especially those that represent a diverse student body, within STEM disciplines is acute. Here, we studied the NoyceSCIENCE program to determine the most impactful experiences offered to undergraduates through the lens of student development theory. We used qualitative coding to analyze data collected from journals ( n = 29) written by students of varying backgrounds, and at varying levels within the program (i.e., the Scholar and Intern level) over a 3-year program running period. We observed that faculty mentorship, the ability of undergraduates to mentor others, volunteer experiences, and learning directly from experts had the greatest influence on student development overall. For Scholars that participate for more than 1 year in the program, access to undergraduate mentoring and volunteering experiences contributed most to student development. We posit that these findings are broadly applicable to other science learning communities and STEM content-focused teacher preparation programs as they are program components that can be integrated in isolation or in their entirety. 

Describes the COMMIT Network, its history, goals, and achievements. 

Non‐proteogenic amino acids and functionalized peptides are important motifs in modern drug discovery. Here we report that Ala^Bcan serve as universal building blocks in the synthesis of a diverse collection of modified amino acids, peptides, and proteins. First, we develop the synthesis of Ala^Bfrom redox‐active esters of aspartic acid resulting in a series of β‐boronoalanine derivatives. Next, we show that Ala^Bcan be integrated into automated oligopeptide solid‐phase synthesis. Ala^Bis compatible with common transformations used in preparative peptide chemistry such as native chemical ligation and radical desulfurization as showcased by total synthesis of Ala^B‐containing ubiquitin. Furthermore, Ala^Breagents participate in Pd‐catalyzed reactions, including C−C cross‐couplings and macrocyclizations. Taken together, Ala^Bsynthons are practical reagents to access modified peptides, proteins, and in the synthesis of cyclic/stapled peptides.

 

Non‐proteogenic amino acids and functionalized peptides are important motifs in modern drug discovery. Here we report that Ala^Bcan serve as universal building blocks in the synthesis of a diverse collection of modified amino acids, peptides, and proteins. First, we develop the synthesis of Ala^Bfrom redox‐active esters of aspartic acid resulting in a series of β‐boronoalanine derivatives. Next, we show that Ala^Bcan be integrated into automated oligopeptide solid‐phase synthesis. Ala^Bis compatible with common transformations used in preparative peptide chemistry such as native chemical ligation and radical desulfurization as showcased by total synthesis of Ala^B‐containing ubiquitin. Furthermore, Ala^Breagents participate in Pd‐catalyzed reactions, including C−C cross‐couplings and macrocyclizations. Taken together, Ala^Bsynthons are practical reagents to access modified peptides, proteins, and in the synthesis of cyclic/stapled peptides.