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Abstract Hydrophosphination using calcium compounds as catalysts under irradiation is described as a foray into s‐block photocatalysis. Transition‐metal compounds have been highly successful hydrophosphination catalysts under photochemical conditions, utilizing substrates previously considered inaccessible. A calcium hydrophosphination precatalyst, Ca(nacnac) (THF) (N(SiMe₃)₂) (1, nacnac = HC[(C(Me)N‐2,6‐ⁱPr₂C₆H₃)]₂), reported by Barrett and Hill, as well as the presumed intermediate, Ca(nacnac) (THF) (PPh₂) (2), and the Schlenk equilibrium product, Ca[N(SiMe₃)₂]₂(THF)₂(3) were screened under photochemical conditions with a range of unsaturated substrates including styrenic alkenes, Michael acceptors, and dienes with modest to excellent conversions, though unactivated alkenes were inaccessible. All compounds exhibit enhanced catalysis under irradiation by light emitting diode (LED)‐generated blue light. Nacnac‐supported compounds generate radicals as evidenced by Electron Paramagnetic Resonance (EPR) spectroscopy and radical trapping reactions, whereas unsupported calcium compounds are EPR silent and appear to undergo hydrophosphination akin to thermal reactions with these compounds. These results buttress the notion that photoactivation of π‐basic ligands is a broad phenomenon, extending beyond the d‐block, but like d‐block metals, consideration of ancillary ligands is essential to avoid radical reactivity. 

Summary Grasses are fundamental to human survival, providing a large percentage of our calories, fuel, and fodder for livestock, and an enormous global carbon sink. A particularly important part of the grass plant is the grain‐producing inflorescence that develops in response to both internal and external signals that converge at the shoot tip to influence meristem behavior. Abiotic signals that trigger reproductive development vary across the grass family, mostly due to the unique ecological and phylogenetic histories of each clade. The time it takes a grass to flower has implications for its ability to escape harsh environments, while also indirectly affecting abiotic stress tolerance, inflorescence architecture, and grain yield. Here, we synthesize recent insights into the evolution of grass flowering time in response to past climate change, particularly focusing on genetic convergence in underlying traits. We then discuss how and why the rewiring of a shared ancestral flowering pathway affects grass yields, and outline ways in which researchers are using this and other information to breed higher yielding, climate‐proof cereal crops. 

Abstract Pressure is mounting to minimize the carbon footprint of chemical industry while increasing its sustainability. An argument is made that working from Green Chemistry principles during discovery‐based catalysis results in effective chemistry and circumvents a need to “rediscover” chemical reactivity under sustainable conditions. Examples of comparative success in selected examples of hydrophosphination catalysis in various degrees of development are provided to support two main ideas: 1) Starting from more sustainable practices in chemical discovery is inertia in methodology that should be overcome, and 2) substantial challenges remain in catalysis for which sustainable solutions would positively impact other areas of chemistry. Examples of successes, even in the face of the challenges noted, are presented herein as indications that even as a starting point, sustainability can meet short‐ and long‐term needs. These ideas indicate critical but simple strategies for fundamental research to be impactful in the sustainability of the chemical industry broadly. 

Abstract Reducing tillage is a key goal for conservation and regenerative agriculture, yet research has struggled to identify ways to increase the use of the practice among farmers. Recent scholarship has identified social capital as an important piece of the adoption puzzle. However, the ways in which farmers' social capital influences conservation practice use are seldom identified or explored. In this study, we tested the effects of three measures of social capital on the adoption of no‐till among 1,523 row crop farmers in the United States Corn Belt. Specifically, we operationalized the extent to which farmers' social networks, network trust, and community conservation norms affect intra‐individual processes and thus influence farmers' decisions regarding adoption. Our results identified key mechanisms for the promotion of conservation practices through social capital. Subjective conservation norms emerged as a main pathway through which farmers' social capital influenced their use of no‐till, indicating that networks, network trust, and community norms can increase adoption through affective paths. We conclude that academic research and policy experts should continue to situate farmers as social actors and pay heed to the norms and cultural expectations surrounding agricultural conservation practices. 

Abstract Climate change is resulting in increasing ocean temperatures and salinity variability, particularly in estuarine environments. Tolerance of temperature and salinity change interact and thus may impact organismal resilience. Populations can respond to multiple stressors in the short‐term (i.e., plasticity) or over longer timescales (i.e., adaptation). However, little is known about the short‐ or long‐term effects of elevated temperature on the tolerance of acute temperature and salinity changes. Here, we characterized the response of the near‐shore and estuarine copepod,Acartia tonsa, to temperature and salinity stress. Copepods originated from one of two sets of replicated >40 generation‐old temperature‐adapted lines: ambient (AM, 18°C) and ocean warming (OW, 22°C). Copepods from these lines were subjected to one and three generations at the reciprocal temperature. Copepods from all treatments were then assessed for differences in acute temperature and salinity tolerance. Development (one generation), three generations, and >40 generations of warming increased thermal tolerance compared to Ambient conditions, with development in OW resulting in equal thermal tolerance to three and >40 generations of OW. Strikingly, developmental OW and >40 generations of OW had no effect on low salinity tolerance relative to ambient. By contrast, when environmental salinity was reduced first, copepods had lower thermal tolerances. These results highlight the critical role for plasticity in the copepod climate response and suggest that salinity variability may reduce copepod tolerance to subsequent warming. 

Summary Wood formation is the Rosetta stone of tree physiology: a traceable, integrated record of physiological and morphological status. It also produces a large and persistent annual sink for terrestrial carbon, motivating predictive understanding. Xylogenesis studies have greatly expanded our knowledge of the intra‐annual controls on wood formation, while dendroecology has quantified the environmental drivers of multi‐annual variability. But these fields operate on different timescales, making it challenging to predict how short (e.g. turgor) and long timescale processes (e.g. disturbance) interactively influence wood formation. Toward this challenge, wood growth responses to natural climate events provide useful but incomplete explanations of tree growth variability. By contrast, direct manipulations of the tree vascular system have yielded unexpected insights, particularly outside of model species like boreal conifers, but they remain underutilized. To improve prediction of global wood formation, we argue for a new generation of experimental manipulations of wood growth across seasons, species, and ecosystems. Such manipulations should expand inference to diverse forests and capture inter‐ and intra‐specific differences in wood growth. We summarize the endogenous and exogenous factors influencing wood formation to guide future experimental design and hypotheses. We highlight key opportunities for manipulative studies integrating measurements from xylogenesis, dendroanatomy, dendroecology, and ecophysiology. 

Abstract Group I alkoxides are highly active precatalysts in the heterodehydrocoupling of silanes and amines to afford aminosilane products. The broadly soluble and commercially available KO^tAmyl was utilized as the benchmark precatalyst for this transformation. Challenging substrates such as anilines were found to readily couple primary, secondary, and tertiary silanes in high conversions (>90 %) after only 2 h at 40 °C. Traditionally challenging silanes such as Ph₃SiH were also easily coupled to simple primary and secondary amines under mild conditions, with reactivity that rivals many rare earth and transition‐metal catalysts for this transformation. Preliminary evidence suggests the formation of hypercoordinated intermediates, but radicals were detected under catalytic conditions, indicating a mechanism that is rare for Si−N bond formation.