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Native legumes are functionally important members of grasslands, but their reintroduction into degraded systems is limited by strong establishment filters. One of these establishment filters might be rhizobia limitation, where legume seedlings are unable to find suitable rhizobia symbionts in grasslands targeted for restoration. To test links between rhizobial inoculation and legume demographic parameters in a grassland restoration context, we evaluated how inoculation with rhizobia altered survival and seed production of a native annual legume (Chamaecrista fasciculata) inoculated with rhizobia and transplanted into a restored prairie. Small mammal herbivory was an important filter affecting survival ofC. fasciculatatransplants, with inoculated plants 81% more likely to be grazed than uninoculated plants. Despite this heavy grazing, plants inoculated with rhizobia survived transplantation 71% more often and, as a result, produced 82% more flowers, experienced 73% more visits by pollinators, and on average produced 220% more seeds. Our results indicate that although herbivory may also shape legume population establishment, at least in some years in some places, rhizobia could alterC. fasciculatainteractions with both herbivores and pollinators and improve population establishment. 

BackgroundEducating children and young people (CYP) from marginalized communities about environmental crises poses a unique dilemma as educators strive to prepare them to deal with the climate crisis without compounding the stressors and fear of an unlivable future many already face. We explored how place‐based civic science (PBCS) can provide opportunities to engage youth in environmental understanding and action through teamwork in which youth feel that they belong to a group larger than themselves and gain a sense of hope from working with others toward shared goals. We argue that combining PCBS pedagogies of collective action and collaborative learning spaces can help to buffer against distress as CYP grapple with global environmental crises. MethodsWe drew from qualitative responses (student reflections and public presentations) of 486 6–12th graders (majority students of color) on what they learned from participating in PBCS projects. Projects involved egalitarian partnerships between adults from environmental organizations, teachers and student teams studying and acting together to mitigate problems and presenting their efforts in public venues. ResultsStudents’ qualitative responses revealed an identification with their team and its goal forged through the work, respect for their voice, belief in their capacity and confidence to take collective action and even enjoyment of working together to address community concerns. ConclusionsPBCS through collective learning/action in student teams and nonhierarchical intergenerational partnerships, and connections that CYP forge with organizations in the broader community, can help to build CYP’s agency and efficacy while addressing “emotionally heavy” issues such as climate change. 

Abstract We present a classroom‐ready activity for high school or college students involving an investigation of a rich, multivariate data set concerning educational and demographic characteristics of K‐12 schools at the state level in the United States. The data set includes educational characteristics such as per‐pupil revenue and graduation rate along with demographic characteristics such as poverty rate and economic segregation. Analysis of the data set sparks conversations regarding educational disparities for students in the United States and could prompt curiosity about educational disparities in other locations as well. 

Summary As global temperatures rise, improving crop yields will require enhancing the thermotolerance of crops. One approach for improving thermotolerance is using bioengineering to increase the thermostability of enzymes catalysing essential biological processes. Photorespiration is an essential recycling process in plants that is integral to photosynthesis and crop growth. The enzymes of photorespiration are targets for enhancing plant thermotolerance as this pathway limits carbon fixation at elevated temperatures. We explored the effects of temperature on the activity of the photorespiratory enzyme glycerate kinase (GLYK) from various organisms and the homologue from the thermophilic algaCyanidioschyzon merolaewas more thermotolerant than those from mesophilic plants, includingArabidopsis thaliana. To understand enzyme features underlying the thermotolerance ofC. merolaeGLYK (CmGLYK), we performed molecular dynamics simulations using AlphaFold‐predicted structures, which revealed greater movement of loop regions of mesophilic plant GLYKs at higher temperatures compared to CmGLYK. Based on these simulations, hybrid proteins were produced and analysed. These hybrid enzymes contained loop regions from CmGLYK replacing the most mobile corresponding loops of AtGLYK. Two of these hybrid enzymes had enhanced thermostability, with melting temperatures increased by 6 °C. One hybrid with three grafted loops maintained higher activity at elevated temperatures. Whilst this hybrid enzyme exhibited enhanced thermostability and a similar K_mfor ATP compared to AtGLYK, its K_mfor glycerate increased threefold. This study demonstrates that molecular dynamics simulation‐guided structure‐based recombination offers a promising strategy for enhancing the thermostability of other plant enzymes with possible application to increasing the thermotolerance of plants under warming climates. 

Few studies have used longitudinal approaches to consider the cumulative impact of COVID-19-related stressors (CRSs) on the psychological adjustment of mothers and children. In the current study, we tracked changes in maternal depressive symptoms and children’s behavioral problems from approximately 2 years before the pandemic (T1) to May through August 2020 (T2). Second, we explored maternal hair cortisol and dehydroepiandrosterone as predictors of change in maternal depressive symptoms. Mothers ( N = 120) reported on maternal and child psychological adjustment at both time points. Hair hormone data were collected in the lab at T1. Results suggest increases in children’s internalizing symptoms from T1 to T2 and that higher levels of CRSs were associated with increased maternal depressive symptoms. Maternal and child adjustment were correlated. Maternal hair cortisol, but not dehydroepiandrosterone, was associated with significant increases in depressive symptoms. Findings underscore the importance of considering the family system and cumulative risk exposure on maternal and child mental health. 

Abstract Earth's magnetotail plays a critical role in the dynamics of the magnetosphere, particularly during intervals of geomagnetic activity. To improve our understanding of the ion dynamics in this region, energetic neutral atom (ENA) imaging can provide global measurements to place in situ measurements in context and validate simulations. The NASA Two Wide‐angle Imaging Neutral‐atom Spectrometers mission provided near‐continuous observations using ENA imagers. ENA data can be used to calculate maps of equatorial ion temperatures that often show observations of regions of enhanced temperatures associated with phenomena in the magnetotail such as magnetic reconnection and narrow flow channels. We present an algorithm that can be used to search through a collection of these maps to identify intervals with such enhancements for further study. The algorithm results are validated against two sets of related phenomena: (a) a database of dipolarizing flux bundle (DFB) measurements from THEMIS and (b) a list of substorm onsets from SuperMAG. We demonstrate that the algorithm is very good at identifying intervals when there are DFB measurements or substorm onsets as long as there sufficient ENA data. We discuss some potential scientific studies that can result from use of the algorithm. We also show a preliminary application of the algorithm to simulation output to demonstrate the usefulness for other datasets, facilitate comparative studies, and introduce a new method for model validation. 

Abstract The synthesis of metal monolayer‐protected clusters (MPCs) is still not well understood. It was recently shown that the mechanism of MPC formation involves sequential growth, wherein small MPCs form first and then grow into progressively larger sizes. The sequential growth model does not entirely explain all experimental observations, however. For example, the evolution of MPC product sizes is found to be a non‐monotonic function of reaction kinetics, whereas the sequential growth model predicts monotonic behavior. Size evolution of MPCs is studied during synthetic reactions for a wide range of kinetics and it is found that all syntheses began with the sequential growth of MPCs but also found that growth transitioned to degradation if reduction kinetics are fast enough to give way to ambient oxidation. It is identified that MPCs can degrade via oxidation during syntheses and in a manner that is opposite to sequential growth, namely by forming smaller known MPC species from larger MPC species. This sequential degradation process therefore played an important role in determining final MPC products for reactions with fast reduction kinetics. Together, complementary oxidative and reductive processes provide a more complete description of MPC synthesis as well as new tools for controlling metal MPC synthesis. 

Abstract Sin Nombre virus (SNV) is a zoonotic virus that is highly pathogenic to humans. The deer mouse,Peromyscus maniculatus, is the primary host of SNV, and SNV prevalence inP. maniculatusis an important indicator of human disease risk. Because the California Channel Islands contain permanent human settlements, receive hundreds of thousands of visitors each year, and can have extremely high densities ofP. maniculatus, surveillance for SNV in islandP. maniculatusis important for understanding the human risk of zoonotic disease. Despite the importance of surveillance on these heavily utilized islands, SNV prevalence (i.e. the proportion ofP. maniculatusthat test positive to antibodies to SNV) has not been examined in the last 13–27 years. We present data on 1,610 mice sampled for four consecutive years (2014–2017) on five of the California Channel Islands: East Anacapa, Santa Barbara, Santa Catalina, San Nicolas, and San Clemente. Despite historical data indicating SNV‐positive mice on San Clemente and Santa Catalina, we detected no SNV‐positive mice on these islands, suggesting very low prevalence or possible loss of SNV. Islands historically free of SNV (East Anacapa, Santa Barbara, and San Nicolas) remained free of SNV, suggesting that rates of pathogen introduction from other islands and/or the mainland are low. Although continued surveillance is warranted to determine whether SNV establishes on these islands, our work helps inform current human disease risk in these locations and suggests that SNV prevalence on these islands is currently very low. 

Abstract Silver monolayer‐protected clusters (MPCs) are an important new class of small metal nanoparticles with discrete sizes and unique properties that are eminently tunable; however, a fundamental understanding of the mechanisms of MPC formation is still lacking. Here, the basic mechanism by which silver‐glutathione MPCs form is established by using real‐time in situ optical measurements and ex situ solution‐phase analyses to track MPC populations in the reaction mixture. These measurements identify that MPCs grow systematically, increasing in size sequentially as they transform from one known species to another, in contrast to existing models. In the new sequential growth model of MPC formation, the relative stability of each species in the series results in thermodynamic preferences for certain species as well as kinetic barriers to transformations between stable sizes. This model is shown to correctly predict the outcome of silver MPC synthetic reactions. Simple analytic expressions and simulations of rate equations are used to further validate the model and study its nature. The sequential growth model provides insights into how reactions may be directed, based on the interplay between relative MPC stabilities and reaction kinetics, providing tools for the synthesis of particular MPCs in high yield. 

Abstract Global change is impacting plant community composition, but the mechanisms underlying these changes are unclear. Using a dataset of 58 global change experiments, we tested the five fundamental mechanisms of community change: changes in evenness and richness, reordering, species gains and losses. We found 71% of communities were impacted by global change treatments, and 88% of communities that were exposed to two or more global change drivers were impacted. Further, all mechanisms of change were equally likely to be affected by global change treatments—species losses and changes in richness were just as common as species gains and reordering. We also found no evidence of a progression of community changes, for example, reordering and changes in evenness did not precede species gains and losses. We demonstrate that all processes underlying plant community composition changes are equally affected by treatments and often occur simultaneously, necessitating a wholistic approach to quantifying community changes.