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Abstract Long-term cold exposure induces many endotherms to invest in metabolic heat production, but how precipitation impacts thermogenic capacity in the context of different thermal conditions is largely undescribed in animals. In this study, songbirds (red crossbills; Loxia curvirostra) were held in warm (21°C) or cold (6°C) temperatures and either dry or rain precipitation treatments while experiencing a more northern or southern latitude photoperiod. We hypothesized that individuals experiencing winter rain would increase investment in thermogenic capacity, metabolic machinery and catabolic enzymes to cope with increased thermogenic demands. Food intake and activity were monitored weekly, summit (Msum) and basal metabolic rates were measured in November, January and February, and tissues were collected at the end of the study. Individuals held in cold rain treatments achieved the highest Msum and had higher food intake, subcutaneous fat, heart mass and metabolic enzyme activities. Furthermore, birds in dry conditions showed slight disinvestment of Msum in late winter, while birds in rain treatments maintained thermogenic investment. Our results suggest that cold rain induces increased investment in thermogenic capacity across the winter season. Thus, rain may offset the potential thermal benefits that warming winters would otherwise provide to small-bodied endotherms. 

Abstract Reversible phenotypic flexibility allows organisms to better match phenotypes to prevailing environmental conditions and may produce fitness benefits. Costs and constraints of phenotypic flexibility may limit the capacity for flexible responses but are not well understood nor documented. Costs could include expenses associated with maintaining the flexible system or with generating the flexible response. One potential cost of maintaining a flexible system is an energetic cost reflected in the basal metabolic rate (BMR), with elevated BMR in individuals with more flexible metabolic responses. We accessed data from thermal acclimation studies of birds where BMR and/or M_sum(maximum cold-induced metabolic rate) were measured before and after acclimation, as a measure of metabolic flexibility, to test the hypothesis that flexibility in BMR (ΔBMR), M_sum(ΔM_sum), or metabolic scope (M_sum − BMR; ΔScope) is positively correlated with BMR. When temperature treatments lasted at least three weeks, three of six species showed significant positive correlations between ΔBMR and BMR, one species showed a significant negative correlation, and two species showed no significant correlation. ΔM_sumand BMR were not significantly correlated for any species and ΔScope and BMR were significantly positively correlated for only one species. These data suggest that support costs exist for maintaining high BMR flexibility for some bird species, but high flexibility in M_sumor metabolic scope does not generally incur elevated maintenance costs. 

Abstract Achieving food security is a critical challenge of the Anthropocene that may conflict with environmental and societal goals such as increased energy access. The “fuel versus food” debate coupled with climate mitigation efforts has given rise to next-generation biofuels. Findings of this systematic review indicate just over half of the studies (56% of 224 publications) reported a negative impact of bioenergy production on food security. However, no relationship was found between bioenergy feedstocks that are edible versus inedible and food security ( P value = 0.15). A strong relationship was found between bioenergy and type of food security parameter ( P value < 0.001), sociodemographic index of study location ( P value = 0.001), spatial scale ( P value < 0.001), and temporal scale ( P value = 0.017). Programs and policies focused on bioenergy and climate mitigation should monitor multiple food security parameters at various scales over the long term toward achieving diverse sustainability goals. 

This report summarizes the discussions from a workshop convened at NSF on May 30-31, 2018 in Alexandria, VA. The overarching objective of the workshop was to rethink the nature and composition of the NSF-supported computational ecosystem given changing application requirements and resources and technology landscapes. The workshop included roughly 50 participants, drawn from high-performance computing (HPC) centers, campus computing facilities, cloud service providers (academic and commercial), and distributed resource providers. Participants spanned both large research institutions and smaller universities. Organized by Daniel Reed (University of Utah, chair), David Lifka (Cornell University), David Swanson (University of Nebraska), Rommie Amaro (UCSD), and Nancy Wilkins-Diehr (UCSD/SDSC), the workshop was motivated by the following observations. First, there have been dramatic changes in the number and nature of applications using NSF-funded resources, as well as their resource needs. As a result, there are new demands on the type (e.g., data centric) and location (e.g., close to the data or the users) of the resources as well as new usage modes (e.g., on-demand and elastic). Second, there have been dramatic changes in the landscape of technologies, resources, and delivery mechanisms, spanning large scientific instruments, ubiquitous sensors, and cloud services, among others.