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Abstract The dataset contains leaf venation architecture and functional traits for a phylogenetically diverse set of 122 plant species (including ferns, basal angiosperms, monocots, basal eudicots, asterids, and rosids) collected from the living collections of the University of California Botanical Garden at Berkeley (37.87° N, 122.23° W; CA, USA) from February to September 2021. The sampled species originated from all continents, except Antarctica, and are distributed in different growth forms (aquatic, herb, climbing, tree, shrub). The functional dataset comprises 31 traits (mechanical, hydraulic, anatomical, physiological, economical, and chemical) and describes six main leaf functional axes (hydraulic conductance, resistance and resilience to damages caused by drought and herbivory, mechanical support, and construction cost). It also describes how architecture features vary across venation networks. Our trait dataset is suitable for (1) functional and architectural characterization of plant species; (2) identification of venation architecture‐function trade‐offs; (3) investigation of evolutionary trends in leaf venation networks; and (4) mechanistic modeling of leaf function. Data are made available under the Open Data Commons Attribution License. 

Students, instructors, and policy makers are in need of research-based recommendations for supporting students’ motivation to pursue STEM fields. The present study addressed this need by examining relations between perceived motivational supports, year-long trajectories of expectancy for success and three task values, and grades among students ( N = 1,021) in a large, gateway engineering course. Results indicated that students with higher motivation at the beginning of the year tended to perceive their class as more motivationally supportive. Controlling for relations between initial motivation and perceptions, perceived instructional supports for mastery goals, autonomy, and competence predicted more positive trajectories of all three task values. Conversely, higher perceived instructor performance goals negatively predicted grades and the slopes of self-efficacy and interest value. Results contribute key understanding about the interconnectedness of individual motivation and climate perceptions, while indicating the importance students place on certain motivationally supportive practices in promoting students’ STEM motivation trajectories. 

Decades of motivation research have yielded a set of Motivation Design Principles (MDPs) that can be leveraged to support the development of student motivation and engagement in the classroom. This article addresses the translation of these guiding principles to teacher professional learning and subsequently, classroom practice. Drawing from published literature, as well as the experiences of a co-design team of motivation and science education researchers and middle school science teachers, we address the landscape of decision points for designing and implementing professional learning focused on supporting middle school students’ motivation in science. We identify 3 key decision points: (1) the extent to which professional learning should focus on general principles or specific practices; (2) the appropriate level(s) for translation of the MDPs into practice; and (3) the creation of opportunities for teacher reflection and self-assessment of their practice on student motivation and engagement. 

Summary Xylem conduits have lignified walls to resist crushing pressures. The thicker the double‐wall (T) relative to its diameter (D), the greater the implosion safety. Having safer conduits may incur higher costs and reduced flow, while having less resistant xylem may lead to catastrophic collapse under drought. Although recent studies have shown that conduit implosion commonly occurs in leaves, little is known about how leaf xylem scalesTvsDto trade off safety, flow efficiency, mechanical support, and cost.We measuredTandDin > 7000 conduits of 122 species to investigate howTvsDscaling varies across clades, habitats, growth forms, leaf, and vein sizes.As conduits become wider, their double‐cell walls become proportionally thinner, resulting in a negative allometry betweenTandD. That is, narrower conduits, which are usually subjected to more negative pressures, are proportionally safer than wider ones. Higher implosion safety (i.e. higherT/Dratios) was found in asterids, arid habitats, shrubs, small leaves, and minor veins.Despite the strong allometry, implosion safety does not clearly trade off with other measured leaf functions, suggesting that implosion safety at whole‐leaf level cannot be easily predicted solely by individual conduits' anatomy.