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Abstract BackgroundTeacher turnover is a dire and chronic problem for many education systems across the globe. According to UNESCO, 70% of teachers will be replaced by 2030. This study investigates the relationship between the retention of science and mathematics teachers and factors related to human, social, structural, and positive psychological capital—a four-capital teacher retention model. More specifically, this study explores how teaching self-efficacy, leadership engagement, teacher-school fit, diversity beliefs, community connections, and professional social network characteristics (e.g., size, bridging, proximity, reach) relate to teacher retention. Additionally, potential differences in retention and the aforementioned factors related to the four-capital model between Master Teaching Fellows (MTFs) and their peers (non-MTFs) with similar human capital (demographics and experience) are explored in this study. Participants were K-12 science and mathematics teachers (85 MTFs and 82 non-MTFs) from six different regions across the U.S. MTFs participated in one of seven long-term (5–6 years) Robert Noyce Master Teaching Fellowship Programs funded by the National Science Foundation. ResultsLeadership engagement was positively associated with shifting (from teaching to a formal leadership position). Teacher-school fit was negatively associated with leaving. For secondary teachers, teaching self-efficacy was positively associated with shifting to a leadership position. Leadership network size, bridging, and geographic proximity variables were positively related to shifting when compared to staying as classroom teachers. Teaching network bridging and leadership network bridging were positively related to leavers when compared to stayers. MTF shifters were likely to shift earlier in their careers than non-MTFs. Lastly, MTFs had higher self-efficacy, geographically larger teaching networks and leadership networks, and more contacts and bridging roles in their leadership networks than non-MTFs. ConclusionFindings provide support for teacher leadership programs in promoting leadership roles and responsibilities for STEM teachers and retaining teachers in STEM education either in the classroom or in administrative roles. These findings suggest that school administrators may also play a key role in encouraging teachers to engage in leadership activities and have a broader impact on public education by, for example, adopting a hybrid model of leadership roles that involves classroom teaching. 

Abstract Community science programs enable the collection of large amounts of important data and enhance the appreciation of science among members of the public. However, there are challenges in the establishment of successful community science programs.We report the challenges associated with the recent establishment of a community science program to monitor rare plants in the geographically diverse southern Illinois, USA region.Over the first 3 years, our program has been successful in the collection of over 250 monitoring records for rare species through the recruitment of a group of passionate volunteers. However, our volunteers are predominantly middle‐income, college educated, white females who are not representative of the population at large of the region. We propose a recruitment strategy to broaden the diversity of our volunteers by better engaging community members who are not typically involved with plant monitoring but are interested in hiking, walking in natural areas, gardening, and restoration activities, and others who would like the opportunity to collaborate with scientists and researchers in addressing an environmental issue.Practical implication: Community science plant monitoring programs face challenges in recruitment, retention, remoteness of field sites and data quality. Addressing these challenges through targeted recruitment strategies aimed at reducing structural and cultural barriers to participation, along with frequent program assessment, is necessary to enhance the success of these programs. 

Urban green space, comprising parks, fields, woodlands, and other semi-natural areas, is a fundamental component of urban ecosystems. The determination of the relationship between urban green space and urban sprawl is necessary to understand urbanization and the provision of urban ecosystem services. It has been hypothesized that the center of urban (i.e., population and economic) areas in fast-growing cities would migrate toward urban green space over time. To test this hypothesis, urban expansion and urban green space expansion were examined in five cities in China and five cities in the U.S. that were experiencing high rates of growth. Landsat images of those cities from 2000 to 2017 were combined with annual population and economic data and used to quantify the extent and migration of the urban green space. These data were analyzed using the center of gravity method by Grether and Mathys and circular statistics were used to determine the relationship between urban green space and urban expansion. Eight out of the ten cities showed a divergent pattern, i.e., the population and economic centers moved in a different direction to that of the urban green space. The movement of the mean centers of the urban green spaces in the U.S. cities was more consistent than that of the Chinese cities. Over 18 years, the movement of urban green space and urban expansion in the 10 cities showed a synchronous growth trend; however, the proportion of urban green space in the cities decreased. The urban expansion rate exceeded the population growth rate, which led to problems with an unreasonable urban sprawl that is likely to deplete the provision of ecosystem services in the future. In conclusion, the centrifugal forces of urban green space that lead to the movement of population and economic centers away from green spaces play a larger role in urban change than the centripetal forces that pull these centers toward urban green space. 

Weed community structure, including composition, taxonomic and functional diversity, may explain variability in crop quality, adding to the variability accounted by management, climatic and genetic factors. Focusing on Mediterranean rainfed wheat crops, we sampled weed communities from 26 fields in Spain that were either organically or conventionally managed. Weed communities were characterized by their abundance and taxonomic, compositional and trait-based measures. Grain protein concentration and the glutenin to gliadin ratio were used as indicators of wheat grain quality. Linear mixed effects models were used to analyze the relationship between crop quality and weed community variables, while accounting for environmental factors. Nitrogen fertilization, previous crop and precipitation explained a large portion of the variation in wheat grain protein concentration (R2marginal = 0.39) and composition (R2marginal = 0.26). Weed community measures had limited effects on grain quality (increasing R2marginal of models by 1% on average). The weed effects were related to the composition and the functional structure of their communities, but not to their abundance. Environmental conditions promoting higher protein concentration were also selecting for weed species with competitive attributes, whereas the role of weed functional diversity depended on the functional trait and on the resource limiting crop grain quality. Understanding the mechanisms of weed effects on crop quality could aid on designing sustainable weed management practices. 

Abstract Glucocorticoids contribute to the daily migration patterns of T cells in well-nourished organisms and are elevated in the malnourished. We examined the effect of malnutrition on T cell migration by comparing the migration patterns of adoptively transferred malnourished and control T cells in the lymphoid organs of malnourished and control recipients. We found that malnourished T cells generally entered lymphoid tissues more efficiently than control T cells, regardless of recipient. Strikingly, the bone marrow of malnourished recipients attracted naïve malnourished T cells, but not control T cells, more efficiently than control bone marrow. In contrast, the spleens of malnourished and control mice attracted similar numbers of naïve T cells. Further experiments revealed that T cells residing in the bone marrow of malnourished mice express higher levels of CCR7 and lower levels of CD11a than control T cells. We also examined the effect of T cell-specific deficiency of the glucocorticoid receptor on T cell migration to the bone marrow in malnourished mice. Indeed, similarly low percentages of glucocorticoid receptor deficient T cells were observed in the bone marrow of malnourished and control mice, indicating that T cell expression of the glucocorticoid receptor is required for T cell migration to the bone marrow. Overall, we have determined that malnutrition modifies both the bone marrow and naïve T cells to promote naïve T cell migration to the bone marrow and that at least the T cell-specific effects are mediated via the glucocorticoid receptor. NSF-MRI [DBI- 1920116] NSF-RUI [IOS-1951881] 

Abstract Malnutrition is associated with reductions in the number and function of T lymphocytes. Previous studies in the lab suggest that malnutrition may also impart a “super-quiescent” phenotype to T cells, perhaps affecting the efficiency of their migration within and between lymph nodes. Thus, the purpose of this study is to evaluate the effect of malnutrition on T cell migration in vivo and to characterize malnutrition-induced changes in the expression of proteins known to be important for T cell migration. To determine if malnourishment alters T cell migration in vivo, we compared lymph node entry rates of adoptively-transferred malnourished and control T cells in malnourished and control recipients. In agreement with other studies, control CD4+ T cells were more efficient than control CD8+ T cells at entering the lymph nodes. Interestingly, regardless of recipient diet, malnourished CD4+ and CD8+ T cells entered the lymph nodes at equivalent rates, suggesting that malnourishment eliminates distinct lymph node entry efficiencies for CD8+ and CD4+ T cells. We also found important differences in the expression of key proteins involved in T cell migration between malnourished and control mice. Overall, we found that malnutrition disrupts T cell migration including the distinct migration efficiencies of CD4+ and CD8+ T cells. An improved understanding of T cell-intrinsic changes that occur during malnourishment should enhance our knowledge of CD4+ and CD8+ T cell migration and shed light on how organisms adapt to malnutrition. Supported by NSF-MRI [DBI- 1920116] NSF-RUI [IOS-1951881] 

Abstract Previous work suggests that glucocorticoids upregulate expression of CD127, an IL-7 receptor component, on peripheral naïve T cells (NT), even though the total number of peripheral NT declines dramatically during malnourishment. We proposed that CD127 up-regulation contributes to peripheral NT reduction by increasing the scavenge rate of IL-7, providing a mechanism to rapidly adjust the total number of NTs during malnutrition. Each malnourished NT would then receive a larger dose of IL-7 than control NTs. We next wondered if this larger dose might confer additional energy-saving behaviors. NT migration across HEV’s may be a high energy-consuming activity. Thus, we compared lymph node entry rates of adoptively-transferred malnourished and control NT in malnourished and control recipients. Control CD4+ NTs migrated more efficiently than control CD8+ NT, but malnourished CD4+ and CD8+ NT migrated at equivalent rates, regardless of recipient diet. We next analyzed expression of proteins known to be involved in NT migration to uncover the currently unknown mechanisms responsible for these various migration patterns. Flow cytometry analysis revealed malnutrition significantly reduces expression of both components of LFA-1 (CD18 and CD11a), CD49d (a VLA-4 component), and S1PR1 in CD4+ and CD8+ NT. We also compared expression levels of ICAM-1 (CD54), a protein expressed in HEV’s which binds to LFA-1 on migrating NT, in malnourished and control lymph node tissue via confocal microscopy. Improved understanding of altered migration molecule expression during malnourishment should enhance our knowledge of the energy-conserving behavior of NT, as well as uncover strategies to improve vaccination responses in malnourished children.